Allergy information for: Milk, cow (Bos taurus)

Clinical History

• Number of Studies:>20
• Number of Patients:>50
• Symptoms:

  Allergy to cow's milk is the most common food allergy in childhood and is experienced, albeit less frequently, in adults. There is an extensive literature on cow's milk allergy and only a summary is listed below.

  Cow's milk allergy differs from, for example, allergy to nuts or crustacea, in that allergy generally develops before age 3 and that fortunately most sufferers become tolerant to milk within a few years. Thus it is not surprising that the distribution of symptoms may be different with, for example, more cases of atopic dermatitis associated with milk allergy.

  Besler et al. (2002) [1499] in a review of more than 20 articles lists symptoms to cow's milk as follows:

  Systemic reactions: anaphylaxis, exercise induced anaphylaxis (including fatal reactions).

  Cutaneous symptoms: angioedema, atopic dermatitis, contact urticaria, dermatitis, eczema, erythema, exanthema, lips oedema, pruritus, redness, swelling of eyelids, urticaria, chronic urticaria.

  Gastrointestinal symptoms: abdominal cramps, abdominal distention, abdominal pain, colic, infantile colic syndrome, colitis, constipation, chronic constipation, diarrhoea, chronic diarrhoea, eosinophilic colitis, eosinophilic gastroenteritis, gastroenteritis, gastro- oesophageal reflux, morphologic lesion, nausea, proctitis, progressive small bowel mucosal damage, occult intestinal bleeding, oropharyngeal itching / swelling, oropharyngeal pruritus, oedema of tongue, acute pancreatitis, loose stools, vomiting as well as general gastrointestinal symptoms. Food protein-induced enterocolitis syndrome was also listed but probably does not involve specific IgE to cow's milk.

  Respiratory symptoms: allergic alveolitis, asthma, bronchospasm, bronchitis, conjunctivitis, coughing, dyspnoea, nasal blockade, allergic rhinitis, rhinitis, rhinoconjunctivitis, serous rhinorrea, sneezing and wheeze.

  Several additional symptoms such as failure to thrive are also associated with allergy to milk, reflecting the age of onset.

Skin Prick Test

• Number of Studies:>20
• Food/Type of allergen:

  Plaza Martin et al (2001) [1198] used alpha-lactalbumin or beta-lactoglobulin (5 mg/ml) and casein (10 mg/ml) (all from CBF Leti, Barcelona, Spain). A result was considered positive when the test produced a skin weal of 3 mm or more in diameter.

  Sporik et al. (2000) [1322] and Hill et al. (2001) [662] used a commercial milk extract.

• Protocol: (controls, definition of positive etc)

  Plaza Martin et al (2001) [1198] considered the test positive when a skin weal was 3 mm or more in diameter.

  Sporik et al. (2000) [1322] and Hill et al. (2001) [662] used a positive, histamine, 1 mg/ml, and a negative control solution. Tests were performed on the patients' backs. The skin weal diameter was measured after 10-15 min for histamine and after 15-20 min for test materials. The results with different diameters were discussed.

• Number of Patients:

  Plaza Martin et al (2001) [1198] tested 49 infants aged less than 6 months and retested them at age 1 year.

  Hill et al. (2001) [662] tested 640 patients with milk extract. The patients were aged below 2 years.

  Sporik et al. (2000) [1322] reported the SPT wheal diameters for 339 patients with milk (from 467 children with suspected food allergies with median age 3.0 years).

• Summary of Results:

  Vanto et al. (2004) [1508] found that the size of the SPT wheal was predictive of the development of tolerance. A wheal size of <5 mm in SPT correctly identified 83% of 124 infants who developed tolerance by aged 4 years, and a wheal size of >5 mm in SPT correctly identified 71% of 39 infants with persistent allergy.

  Hill et al. (2001) [662] found that 125/640 patients gave positive SPT defined as 6 mm diameters. Comparison with IgE tests on sera for SPT positive patients showed that 20, 14, 29, 61 and 1 had 0 - 0.34, 0.35 - 0.69, 0.7 - 3.49, 3.5 - 17.5 and >17.5 kU/l respectively (or AEU/ml for pre-1999 tests).

  Plaza Martin et al (2001) [1198] found that positive SPT predicted all positive oral challenges with immediate reactions. Positive challenges following negative SPTs were associated with delayed reactions.

  Sporik et al. (2000) [1322] found that all patients with SPT wheal diameters >8 mm were allergic. At 3 mm, approximately equal numbers were challenge positive and negative. They recommend 6 mm as confirming allergy, so that challenge is unnecessary.

IgE assay (by RAST, CAP etc)

• Number of Studies:0
• Food/Type of allergen:Commercial extracts.
• IgE protocol:

  Celik-Bilgili et al. (2005) [1309], Perry et al. (2004) [1218], Shek et al. (2004) [1214], Szabo & Eigenmann (2000) [1068] and Sicherer & Sampson (1999) [1208] used the Pharmacia CAP System FEIA.

  Szabo & Eigenmann (2000) [1068] used ELISA for IgG determination.

• Number of Patients:

  Perry et al. (2004) [1218] measured IgE levels to milk in 159 children who were subjected to oral challenge with milk.

  Shek et al. (2004) [1214] repeatedly measured IgE levels in 49 children who were also subjected to oral challenge with milk.

  Sicherer & Sampson (1999) [1208] measured IgE levels to milk in sera from 64 children. These were divided into 4 groups: 30 under age 3 at time of positive oral challenge or anaphylactic reaction; 20 over age 9 at the time of positive oral challenge or anaphylactic reaction; 11 with samples from before tolerance was achieved; 16 samples from patients after they lost sensitivity with 9 paired samples between groups 3 and 4.

• Summary of Results:Sicherer & Sampson (1999) [1208] reported that no single allergen dominanted IgE binding patterns. However, those with persistent allergy over age 9 years had significantly elevated levels of milk and casein-specific IgE compared with younger children. These results were consistent with the results of previous studies. In detail, all allergic children had detectable casein and whey-specific IgE. Beta-lactoglobulin-specific IgE was undetectable in 7/30 (23%) in Group I, 7/20 (35%) in Group II and in 5/11 (45%) of the children in Group III. Alpha-lactalbumin-specific IgE was undetectable in 5/30 (17%) in Group I, 6/20 (30%) in Group II, and in 5/11 (45%) of Group III. Bovine serum albumin-specific IgE was undetectable in approximately 50% of each group.

  Szabo & Eigenmann (2000) [1068] report that sera from the cow's milk-allergic patients contained specific IgE concentrations to milk ranging from 8.2 to 4225 IU/ml, with a median of 39.8 IU/ml. Both allergic patients and controls had similar IgG levels to milk.

  Perry et al. (2004) [1218] report that 11/34 patients with a history suggestive of allergy with specific IgE <0.35 KU/l were positive on challenge, 31/56 with 0.35 - 2 KU/l were positive, 20/32 with 2 - 3 KU/l were positive and 26/31 with >3 KU/l. Of 6 patients with an unclear history, 1/2 with <0.35 KU/l and 1/2 with 0.35 - 2 KU/l were positive on challenge but 2 with >3 KU/l did not react.

  Shek et al. (2004) [1214] determined the probability of developing tolerance to milk based on the % decrease in specific IgE over 12 months as 0.31 (50% reduction), 0.45 (75% reduction), 0.66 (90% reduction) and 0.94 (99% reduction) for children diagnosed before age 4. In total 16 children became tolerant and 33 remained allergic. No clear relationships predicting tolerance were seen in children first diagnosed with food allergy when older than 4 years although only 6 fell into this category.

  Celik-Bilgili et al. (2005) [1309] found a correlation between the measured IgE levels to milk and the probability of a positive challenge. However, only the 21 patients with >50 kU/l were all challenge positive. Most patients had lower levels of specific IgE: 141 with <0.35 kU/l, 46 with 0.35-0.7 kU/l, 87 with 0.7-3.5 kU/l, 61 with 3.5-17.5 kU/l and 41 with 17.5-50 kU/l and approximate probabilities of 0.23, 0.43, 0.5, 0.7 and 0.75 respectively.

  Sampson (2001) [651] described a decision point with a 95% predicted probability of a positive DBPCFC of 15 kU/l specific IgE to cow's milk in the US population whilst Garcia-Ara et al. (2001) [1328] reported 5 kU/l specific IgE to cow's milk as a 95% positive predicted value in Spanish infants. In contrast to these studies, no useful predictive decision points could be obtained for German children by Celik-Bilgili et al. (2005) [1309]. Lin et al. (1998) [1412] also reported >0.7 ku/l levels of IgE specific to proteins of cow's milk in sera from atopic children without clinical allergy to milk.

Immunoblotting

• Immunoblotting separation:

  Docena et al. (1996) [1408] separated proteins in 1D 14% polyacrylamide gels (Laemmli, 1970 [948]) with 35 µg per lane. 2-mercaptoethanol was used in some separations.

  Szabo & Eigenmann (2000) [1068] used SDS PAGE with a Bio-Rad Mini Protean II (Bio-Rad, Richmond, CA, USA) at 80 V through the stacking gel, and at 160 V through the running gel. Cow's milk was run reduced by 2% beta-mercaptoethanol but unboiled.

  Natale et al. (2004) [1409] used 1D electrophoresis using 12% NuPage ZOOM gels (Invitrogen) and 2D electrophoresis with IEF in 7M urea, 2M thiourea, 4% CHAPS, 0.2% BioLyte (Bio-Rad) either 3-6 or 3-10 NL, 65 mM DTT and traces of Bromo Phenol Blue, followed by treatment with 50 mM DTT, then 65 mM iodoacetamide and SDS PAGE in a 12% acrylamide gel.

• Immunoblotting detection method:

  Docena et al. (1996) [1408] electrotransferred proteins to 0.45 µm nitrocellulose membranes for 1 hour at 270 mA. The membranes were blocked with PBS containing 5% (v/v) horse serum and cut into strips. Strips were incubated with sera diluted 1/5 (v/v) in PBS for 12 hours at room temperature. After washing, the strips were incubated with anti-IgE (or anti-IgG) antibodies conjugated to alkaline phosphatase for 12 hours at room temperature. Binding was revealed with 5-BCIP/NBT substrate (Sigma).

  Szabo & Eigenmann (2000) [1068] electrotransferred proteins to nitrocellulose (Protran^TM 0.2 µm). Blots were blocked for 1 h in phosphate buffered saline plus 0.05% (v/v) Tween (PBS-T) with 0.5% (w/v) gelatin and then incubated with serum and PBS-T (1:10 v/v dilution for IgE, 1:200 (v/v) for IgG, and 1:20 (v/v) for IgG4) for 2 h at room temperature on a rocking platform. Antibodies were bound by a goat anti-human IgE at 0.5 µg/ml (Kirkegaard and Perry, Gaitersburg, USA), or a sheep antihuman IgG (0.5 µg/ml) or a mouse antihuman IgG4 (1:1000 v/v) (Serotec Ltd, Oxford, UK). Five washes (for 5 min) with PBS-T were done between each step. The blots were developed with DAB^TM(Sigma).

  Natale et al. (2004) [1409] electroblotted proteins onto 0.2 µm nitrocellulose (Sigma) in a semi wet module (Invitrogen). Membranes were blocked with tris buffered saline, pH 7.4, with 0.3% v/v Tween and incubated overnight with sera diluted 1:5 by the same buffer with 0.05% (v/v) Tween and 0.05% (w/v) gelatin (Bio-Rad). The membranes were rinsed with tris buffered saline with 0.03% (v/v) Tween and incubated with alkaline phosphatase-conjugated goat anti-human-IgE diluted 1:1000 (v/v) in the tris/Tween/gelatin buffer. Binding was revealed with BCIP/NBT (Bio-Rad).

• Immunoblotting results:

  Docena et al. (1996) [1408] report that serum IgE from 80/80 individuals bound to casein aggregates. 10/80 sera contained IgE against beta-lactoglobin and 5/80 against alpha-lactalbumin. Both IgE and IgG bound to masses >150 kDa and 60-70 kDa, which disappear on reduction, with IgE also reacting to alpha- or beta-caseins. If the high mass aggregates are reducted and treated with urea, some binding to aggregates and also to caseins remains. No IgE binding to bovine serum albumin was observed. In addition, inhibition experiments were used to rule out bovine serum albumin as the 60-70 kDa band and confirming IgE binding to caseins and beta-lactoglobin.

  Szabo & Eigenmann (2000) [1068] reported serum IgE binding to the casein fractions in 9/10 cow's milk allergic individuals, to beta-lactoglobulin in 5/10 and to alpha-lactabumin in 2/10. IgG and IgG4 bound to the fractions in a very similar way to IgE, suggesting that allergy results from a failure of class switching.

  Natale et al. (2004) [1409] used 20 sera from patients from 4 months to 14 months. They found that 55% of the individuals had serum IgE against alpha S1-casein, 90% against alpha S2-casein, 15% against beta-casein, 50% against kappa-casein, 45% against beta-lactoglobulin, 45% against bovine serum albumin, 95% against IgG heavy chain and 50% against lactoferrin, with none binding alpha-lactalbumin.

Oral provocation

• Number of Studies:>20
• Food used and oral provocation vehicle:

  Celik-Bilgili et al. (2005) [1309] gave doses of 0.1, 0.3, 1.0, 3.0, 10.0, 30.0, 100.0 mls of fresh pasteurized cow's milk (total 144.4 mls) or placebo (Neocate^®, SHS, Liverpool, UK) at 20 min. intervals. The children were observed for 48 h after each challenge on an in-patient basis in order to detect late clinical reactions.

  Perry et al. (2004) [1217] gave the food in escalating doses every 15 min. until 4 g (<5 years old) or 8 g (>5 years old) of milk protein had been ingested. The challenge was terminated on objective symptoms or when subjective symptoms such as abdominal pain worsened. Patients were observed in the clinic for a minimum of 4 hours or until signs of clinical reactivity subsided for those patients who failed the challenge and were instructed before discharge to contact a physician on possible late-phase reactions.

  Plaza Martin et al (2001) [1198] gave up to 20 ml of adapted cow's milk protein formula (Nidina 1 ^®, Nestle, Spain). Vital signs were monitored every 30 minutes during the first hour after formula intake and again every hour for 3 hours after the last dose administered in the challenge test. The infants were monitored for 24 hours after the challenge test.

  Sporik et al. (2000) [1322] gave 1 drop of milk inside lip, 0.5, 2.5, 5, 10, 20, and 30 mLs at 30 minute intervals. On day 2: 30, 60 and 120 mLs at 30 minute intervals and on day 3: normal volumes of milk, i.e. > 450 mLs per day.

• Blind:

  Plaza Martin et al (2001) [1198], Perry et al. (2004) [1217] used open challenge.

  Celik-Bilgili et al. (2005) [1309] used DBPCFC in general but open challenges for babies below 1 year in age.

• Number of Patients:

  Celik-Bilgili et al. (2005) [1309] challenged 398 children with cow's milk. Most showed symptoms of atopic dermatitis.

  Plaza Martin et al (2001) [1198] challenged 49 infants aged less than 6 months and rechallenged those with negative SPT and negative tests for sera IgE after an exclusion diet at age 1 year.

  Sporik et al. (2000) [1322] challenged 339 patients with cow's milk with a median age of 31 months. 120 were less than 2 years old.

• Dose response:

  Taylor et al. (2002) [639] have collected data from several studies with the aim of defining thresholds for reaction to milk (299 patients in total). Studies have used liquid cow's milk, nonfat dry milk, or infant formula (Taylor et al, 2004) [1505]. The lowest provoking dose was 0.02 mL of milk, which was seen in 21 patients by open challenge.

  Morrisset et al. (2003) [613] considering objective reactions apart from abdominal pain in children, found that 5% reacted to 0.8 mL of milk and 1.7% (2/59) reacted to the lowest reactive dose of 0.1 mL of milk.

• Symptoms:

  Celik-Bilgili et al. (2005) [1309] reported that 49% of the milk challenges were positive. Symptoms for early reactions to milk, egg, wheat and soy were listed as urticaria (55%), gastrointestinal (14%), urticaria and gastrointestinal (22%), respiratory and gastrointestinal (1%), respiratory and urticaria (7%), and analphylaxis (1%). Few reactions to egg or milk were delayed reactions (mostly atopic dermatitis).

  Perry et al. (2004) [1217] reported 90 out of 161 patients (56%) reacted to a challenge with milk. The median food-specific IgE for patients reacting was 2.0 kU_A/L and the median percent of challenge food ingested was 25%. The symptoms in the clinical history of the 90 patients included eczema (60%), asthma (57%) and allergic rhinitis (47%). 89% suffered from another food allergy. Symptoms on challenge were cutaneous (68, 75%), oral (23, 26%), upper respiratory (16, 18%), lower respiratory (24, 27%) and gastrointestinal (37, 41%) with no cardiovascular symptoms reported. Reactions were classified as mild (33,37%), moderate (33, 37%) and severe (24, 27%). IgE levels to milk did not predict severity.

  Plaza Martin et al (2001) [1198] reported immediate reactions in 92 % of the children at the time of diagnosis. Symptoms were rash in 63 %, vomiting in 43 %, anaphylaxis in 10 % and respiratory symptoms in 12 % (respiratory symtoms always occurred with other symptoms). 8% of the clinical reactions were late and all manifested as dyspepsia. On retesting at age 1 year, only 5 children (21%) presented a positive reaction which did not occur in the first 24 hours after the reintroduction of cow's milk protein to the diet.

  Sporik et al. (2000) [1322] report 143 positive challenges to milk with urticaria (73%), eczema flare (7%), vomiting (14%), diarrhoea, colic or abdominal pain (21%), respiratory (14%) and rhinitis (15%).

IgE cross-reactivity and Polysensitisation

Other Clinical information

Reviews (6)

• Wal JM.
  Bovine milk allergenicity.
  Ann Allergy Asthma Immunol. 93(5 Suppl 3):S2-11.. 2004
  PUBMEDID: 15562868
• Eigenmann PA.
  Anaphylaxis to cow's milk and beef meat proteins.
  Ann Allergy Asthma Immunol. 89(6 Suppl 1):61-4.. 2002
  PUBMEDID: 12487207
• Besler M, Eigenmann F, Schwartz RH.
  Allergen Data Collection - Update: Cow's Milk (Bos domesticus)
  Internet Symposium on Food Allergens 4(1): 19-106. 2002
  PUBMEDID:
• Heine RG, Elsayed S, Hosking CS, Hill DJ.
  Cow's milk allergy in infancy.
  Curr Opin Allergy Clin Immunol. 2(3):217-225. . 2002
  PUBMEDID: 12045418
• Wal JM.
  Cow's milk proteins/allergens.
  Ann Allergy Asthma Immunol. 89(6 Suppl 1):3-10.. 2002
  PUBMEDID: 12487197
• Farrell HM Jr, Jimenez-Flores R, Bleck GT, Brown EM, Butler JE, Creamer LK, Hicks CL, Hollar CM, Ng-Kwai-Hang KF, Swaisgood HE.
  Nomenclature of the proteins of cows' milk--sixth revision.
  J Dairy Sci. 87(6):1641-1674.. 2004
  PUBMEDID: 15453478

References (57)

• Chatchatee P, Jarvinen KM, Bardina L, Vila L, Beyer K, Sampson HA.
  Identification of IgE and IgG binding epitopes on beta- and kappa-casein in cow's milk allergic patients.
  Clin Exp Allergy. 31(8):1256-1262. . 2001
  PUBMEDID: 11529896
• Vila L, Beyer K, Jarvinen KM, Chatchatee P, Bardina L, Sampson HA.
  Role of conformational and linear epitopes in the achievement of tolerance in cow's milk allergy.
  Clin Exp Allergy. 31(10):1599-1606.. 2001
  PUBMEDID: 11678861
• Järvinen KM, Chatchatee P, Bardina L, Beyer K, Sampson HA.
  IgE and IgG binding epitopes on alpha-lactalbumin and beta-lactoglobulin in cow's milk allergy.
  Int Arch Allergy Immunol. 126(2):111-118. . 2001
  PUBMEDID: 11729348
• Daher S, Tahan S, Sole D, Naspitz CK, Da Silva Patricio FR, Neto UF, De Morais MB.
  Cow's milk protein intolerance and chronic constipation in children.
  Pediatr Allergy Immunol. 12(6):339-342.. 2001
  PUBMEDID: 11846872
• Caffarelli C, Plebani A, Poiesi C, Petroccione T, Spattini A, Cavagni G.
  Determination of allergenicity to three cow's milk hydrolysates and an amino acid-derived formula in children with cow's milk allergy.
  Clin Exp Allergy 32(1):74-79.. 2002
  PUBMEDID: 12002741
• Järvinen KM, Beyer K, Vila L, Chatchatee P, Busse PJ, Sampson HA.
  B-cell epitopes as a screening instrument for persistent cow's milk allergy.
  J Allergy Clin Immunol. 110(2):293-297.. 2002
  PUBMEDID: 12170271
• Busse PJ, Järvinen KM, Vila L, Beyer K, Sampson HA.
  Identification of sequential IgE-binding epitopes on bovine alpha(s2)-casein in cow's milk allergic patients.
  Int Arch Allergy Immunol. 129(1):93-96.. 2002
  PUBMEDID: 12373003
• Sampson HA
  Utility of food-specific IgE concentrations in predicting symptomatic food allergy.
  J Allergy Clin Immunol. 107(5):891-6. 2001
  PUBMEDID: 11344358
• Sampson HA, Ho DG.
  Relationship between food-specific IgE concentrations and the risk of positive food challenges in children and adolescents.
  J Allergy Clin Immunol. 100(4):444-451.. 1997
  PUBMEDID: 9338535
• Perry TT, Matsui EC, Conover-Walker MK, Wood RA.
  Risk of oral food challenges.
  J Allergy Clin Immunol. 114(5):1164-1168.. 2004
  PUBMEDID: 15536426
• Perry TT, Matsui EC, Conover-Walker MK, Wood RA.
  The relationship of allergen-specific IgE levels and oral food challenge outcome.
  J Allergy Clin Immunol. 114(1):144-149. 2004
  PUBMEDID: 15241358
• Shek LP, Soderstrom L, Ahlstedt S, Beyer K, Sampson HA.
  Determination of food specific IgE levels over time can predict the development of tolerance in cow's milk and hen's egg allergy.
  J Allergy Clin Immunol. 2004 Aug;114(2):387-91.. 2004
  PUBMEDID: 15316521
• Sicherer SH, Sampson HA.
  Cow's milk protein-specific IgE concentrations in two age groups of milk-allergic children and in children achieving clinical tolerance.
  Clin Exp Allergy 29(4):507-512.. 1999
  PUBMEDID: 10202365
• Stoger P, Wuthrich B.
  Type I allergy to cow milk proteins in adults. A retrospective study of 34 adult milk- and cheese-allergic patients.
  Int Arch Allergy Immunol. 102(4):399-407.. 1993
  PUBMEDID: 8241802
• Hill DJ, Hosking CS, Reyes-Benito LV.
  Reducing the need for food allergen challenges in young children: a comparison of in vitro with in vivo tests.
  Clin Exp Allergy. 31(7):1031-5.. 2001
  PUBMEDID: 11467993
• Chatchatee P, Jarvinen KM, Bardina L, Beyer K, Sampson HA.
  Identification of IgE- and IgG-binding epitopes on alpha(s1)-casein: differences in patients with persistent and transient cow's milk allergy.
  J Allergy Clin Immunol. 107(2):379-383.. 2001
  PUBMEDID: 11174208
• Hidvegi E, Cserhati E, Kereki E, Savilahti E, Arato A.
  Serum immunoglobulin E, IgA, and IgG antibodies to different cow's milk proteins in children with cow's milk allergy: association with prognosis and clinical manifestations.
  Pediatr Allergy Immunol. 13(4):255-261.. 2002
  PUBMEDID: 12390441
• Szabo I, Eigenmann PA.
  Allergenicity of major cow's milk and peanut proteins determined by IgE and IgG immunoblotting.
  Allergy 55(1):42-49.. 2000
  PUBMEDID: 10696855
• Hill DJ, Heine RG, Hosking CS.
  The diagnostic value of skin prick testing in children with food allergy.
  Pediatr Allergy Immunol. 15(5):435-441.. 2004
  PUBMEDID: 15482519
• Norgaard A, Bindslev-Jensen C, Skov PS, Poulsen LK.
  Specific serum IgE in the diagnosis of egg and milk allergy in adults.
  Allergy 50(8):636-647.. 1995
  PUBMEDID: 7503399
• Plaza Martin AM, Martin Mateos MA, Giner Munoz MT, Sierra Martinez JI.
  Challenge testing in children with allergy to cow's milk proteins.
  Allergol Immunopathol (Madr). 29(2):50-54.. 2001
  PUBMEDID: 11420027
• Bernard H, Creminon C, Yvon M, Wal JM.
  Specificity of the human IgE response to the different purified caseins in allergy to cow's milk proteins.
  Int Arch Allergy Immunol. 115(3):235-244.. 1998
  PUBMEDID: 9531166
• Shimojo N, Kohno Y, Katsuki T, Honma K, Yamaguchi K, Tsunoo H, Takahashi T, Kaminogawa S, Niimi H.
  Comparison of specificity between IgG, IgE and T cells to three casein components: implication for the role of circulating allergen-specific T cells in food allergy.
  Acta Paediatr Jpn. 39(4):416-421. . 1997
  PUBMEDID: 9316283
• Spuergin P, Mueller H, Walter M, Schiltz E, Forster J.
  Allergenic epitopes of bovine alpha S1-casein recognized by human IgE and IgG.
  Allergy 51(5):306-312.. 1996
  PUBMEDID: 8836334
• Docena GH, Fernandez R, Chirdo FG, Fossati CA.
  Identification of casein as the major allergenic and antigenic protein of cow's milk.
  Allergy 51(6):412-416.. 1996
  PUBMEDID: 8837665
• Natale M, Bisson C, Monti G, Peltran A, Garoffo LP, Valentini S, Fabris C, Bertino E, Coscia A, Conti A.
  Cow's milk allergens identification by two-dimensional immunoblotting and mass spectrometry.
  Mol Nutr Food Res. 48(5):363-369.. 2004
  PUBMEDID: 15672476
• Motrich RD, Gottero C, Rezzonico C, Rezzonico C, Riera CM, Rivero V.
  Cow's milk stimulated lymphocyte proliferation and TNFalpha secretion in hypersensitivity to cow's milk protein.
  Clin Immunol. 2003 Nov;109(2):203-211.. 2003
  PUBMEDID: 14597219
• Lin HY, Shyur SD, Fu JL, Lai YC.
  Whey and casein specific IgE and the cow's milk challenge test for atopic children.
  Zhonghua Min Guo Xiao Er Ke Yi Xue Hui Za Zhi. 39(2):99-102. . 1998
  PUBMEDID: 9599898
• Garcia-Ara C, Boyano-Martinez T, Diaz-Pena JM, Martin-Munoz F, Reche-Frutos M, Martin-Esteban M.
  Specific IgE levels in the diagnosis of immediate hypersensitivity to cows' milk protein in the infant.
  J Allergy Clin Immunol. 107(1):185-190.. 2001
  PUBMEDID: 11150010
• Osterballe M, Andersen KE, Bindslev-Jensen C.
  The diagnostic accuracy of the atopy patch test in diagnosing hypersensitivity to cow's milk and hen's egg in unselected children with and without atopic dermatitis.
  J Am Acad Dermatol. 51(4):556-562.. 2004
  PUBMEDID: 15389190
• Laemmli UK
  Cleavage of structural proteins during the assembly of the head of bacteriophage T4
  Nature 227:680-685. 1970
  PUBMEDID: 5432063
• Bernard H.
  IgE Cross-reactivity with Caseins from Different Species in Humans Allergic to Cow's Milk
  Food and Agricultural Immunology 11(1), 101 - 111. 1999
  PUBMEDID:
• Cantisani A, Giuffrida MG, Fabris C, Bertino E, Coscia A, Oggero R, Monti G, Stroppiana P, Conti A.
  Detection of specific IgE to human milk proteins in sera of atopic infants.
  FEBS Lett. 412(3):515-517.. 1997
  PUBMEDID: 9276457
• Celik-Bilgili S, Mehl A, Verstege A, Staden U, Nocon M, Beyer K, Niggemann B.
  The predictive value of specific immunoglobulin E levels in serum for the outcome of oral food challenges.
  Clin Exp Allergy 35(3):268-273.. 2005
  PUBMEDID: 15784102
• Sporik R, Hill DJ, Hosking CS.
  Specificity of allergen skin testing in predicting positive open food challenges to milk, egg and peanut in children.
  Clin Exp Allergy 30(11):1540-1546.. 2000
  PUBMEDID: 11069561
• Roehr CC, Reibel S, Ziegert M, Sommerfeld C, Wahn U, Niggemann B.
  Atopy patch tests, together with determination of specific IgE levels, reduce the need for oral food challenges in children with atopic dermatitis.
  J Allergy Clin Immunol. 107(3):548-553.. 2001
  PUBMEDID: 11240959
• Saarinen KM, Sarnesto A, Savilahti E.
  Markers of inflammation in the feces of infants with cow's milk allergy.
  Pediatr Allergy Immunol. 13(3):188-194.. 2002
  PUBMEDID: 12144641
• Host A, Husby S, Osterballe O.
  A prospective study of cow's milk allergy in exclusively breast-fed infants. Incidence, pathogenetic role of early inadvertent exposure to cow's milk formula, and characterization of bovine milk protein in human milk.
  Acta Paediatr Scand. 77(5):663-670.. 1988
  PUBMEDID: 3201972
• Bernhisel-Broadbent J, Yolken RH, Sampson HA.
  Allergenicity of orally administered immunoglobulin preparations in food-allergic children.
  Pediatrics. 87(2):208-214.. 1991
  PUBMEDID: 1987533
• Taylor SL, Hefle SL, Bindslev-Jensen C, Bock SA, Burks AW Jr, Christie L, Hill DJ, Host A, Hourihane JO, Lack G, Metcalfe DD, Moneret-Vautrin DA, Vadas PA, Rance F, Skrypec DJ, Trautman TA, Yman IM, Zeiger RS.
  Factors affecting the determination of threshold doses for allergenic foods: how much is too much?
  J Allergy Clin Immunol. 109(1):24-30. 2002
  PUBMEDID: 11799361
• Taylor SL, Hefle SL, Bindslev-Jensen C, Atkins FM, Andre C, Bruijnzeel-Koomen C, Burks AW, Bush RK, Ebisawa M, Eigenmann PA, Host A, Hourihane JO, Isolauri E, Hill DJ, Knulst A, Lack G, Sampson HA, Moneret-Vautrin DA, Rance F, Vadas PA, Yunginger JW, Zeiger RS, Salminen JW, Madsen C, Abbott P.
  A consensus protocol for the determination of the threshold doses for allergenic foods: how much is too much?
  Clin Exp Allergy 34(5):689-695.. 2004
  PUBMEDID: 15144458
• Restani P, Beretta B, Fiocchi A, Ballabio C, Galli CL.
  Cross-reactivity between mammalian proteins.
  Ann Allergy Asthma Immunol. 89(6 Suppl 1):11-15.. 2002
  PUBMEDID: 12487198
• Restani P, Gaiaschi A, Plebani A, Beretta B, Velona T, Cavagni G, Poiesi C, Ugazio AG, Galli CL.
  Evaluation of the presence of bovine proteins in human milk as a possible cause of allergic symptoms in breast-fed children.
  Ann Allergy Asthma Immunol. 84(3):353-360.. 2000
  PUBMEDID: 10752922
• Businco L, Giampietro PG, Lucenti P, Lucaroni F, Pini C, Di Felice G, Iacovacci P, Curadi C, Orlandi M.
  Allergenicity of mare's milk in children with cow's milk allergy.
  J Allergy Clin Immunol. 105(5):1031-1034.. 2000
  PUBMEDID: 10808187
• Bellioni-Businco B, Paganelli R, Lucenti P, Giampietro PG, Perborn H, Businco L.
  Allergenicity of goat's milk in children with cow's milk allergy.
  J Allergy Clin Immunol. 103(6):1191-1194. . 1999
  PUBMEDID: 10359905
• Restani P, Gaiaschi A, Plebani A, Beretta B, Cavagni G, Fiocchi A, Poiesi C, Velona T, Ugazio AG, Galli CL.
  Cross-reactivity between milk proteins from different animal species.
  Clin Exp Allergy. 29(7):997-1004.. 1999
  PUBMEDID: 10383602
• Martelli A, Bouygue GR, Isoardi P, Marelli O, Sarratud T, Fiocchi A.
  Oral food challenges in children in Italy.
  Allergy 60(7):907-911.. 2005
  PUBMEDID: 15932381
• Davidovits M, Levy Y, Avramovitz T, Eisenstein B.
  Calcium-deficiency rickets in a four-year-old boy with milk allergy.
  J Pediatr. 122(2):249-251.. 1993
  PUBMEDID: 8429441
• Castile RG, Marks LJ, Stickler GB.
  Vitamin D deficiency rickets. Two cases with faulty infant feeding practices.
  Am J Dis Child. 129(8):964-966.. 1975
  PUBMEDID: 1163511
• Carvalho NF, Kenney RD, Carrington PH, Hall DE.
  Severe nutritional deficiencies in toddlers resulting from health food milk alternatives.
  Pediatrics 107(4):E46.. 2001
  PUBMEDID: 11335767
• Fox AT, Du Toit G, Lang A, Lack G.
  Food allergy as a risk factor for nutritional rickets.
  Pediatr Allergy Immunol. 15(6):566-569.. 2004
  PUBMEDID: 15610373
• Jensen VB, Jorgensen IM, Rasmussen KB, Molgaard C, Prahl P.
  Bone mineral status in children with cow milk allergy.
  Pediatr Allergy Immunol. 15(6):562-565. . 2004
  PUBMEDID: 15610372
• Martelli A, De Chiara A, Corvo M, Restani P, Fiocchi A.
  Beef allergy in children with cow's milk allergy; cow's milk allergy in children with beef allergy.
  Ann Allergy Asthma Immunol. 89(6 Suppl 1):38-43.. 2002
  PUBMEDID: 12487203
• Morisset M, Moneret-Vautrin DA, Kanny G, Guenard L, Beaudouin E, Flabbee J, Hatahet R.
  Thresholds of clinical reactivity to milk, egg, peanut and sesame in immunoglobulin E-dependent allergies: evaluation by double-blind or single-blind placebo-controlled oral challenges.
  Clin Exp Allergy. 33(8):1046-1051.. 2003
  PUBMEDID: 12911777
• Karlsson MR, Rugtveit J, Brandtzaeg P.
  Allergen-responsive CD4+CD25+ regulatory T cells in children who have outgrown cow's milk allergy.
  J Exp Med. 199(12):1679-88.. 2004
  PUBMEDID: 15197226
• Werfel SJ, Cooke SK, Sampson HA.
  Clinical reactivity to beef in children allergic to cow's milk.
  J Allergy Clin Immunol. 99(3):293-300.. 1997
  PUBMEDID: 9058683
• Vanto T, Helppila S, Juntunen-Backman K, Kalimo K, Klemola T, Korpela R, Koskinen P.
  Prediction of the development of tolerance to milk in children with cow's milk hypersensitivity.
  J Pediatr. 144(2):218-222.. 2004
  PUBMEDID: 14760265

Biochemical Information for Alpha S1-Casein

• Allergen Name:Alpha S1-Casein
• Alternatve Allergen Names:Bos d 8 (name for all caseins)
• Allergen Designation:Major
• Protein Family:Pfam PF00363; Casein family
• Sequence Known?:Yes
• Allergen accession No.s:

  http://us.expasy.org/cgi-bin/niceprot.pl?P02662

  Variants AAA30478, AAA62707, AAA30428, AAA30429 show minor differences.

• 3D Structure Accession No.:N/A
• Calculated Masses:

  24529 Da (precursor)
  23614 Da (mature variant B)

• Experimental Masses:27-32 kDa depending on conditions. Creamer & Richardson, 1984 [1417] noted that caseins run more slowly under SDS-PAGE than would be predicted from their calculated mass.
• Oligomeric Masses:

  Caseins form stable micellar calcium phosphate protein complexes. However, large aggregates are also reported.

• Allergen epitopes:

  Epitope mapping studies have been reported:

  1. Using synthetic peptides alone

  Chatchatee et al. (2001) [1200] identified sequential IgE-binding regions in Alpha_s1-casein at AA 17-36, 39-48, 69-78, 93-102, 109-120, 123-132, 139-154, 159-174 and 173-194 using sera from 9 older children (> 9 years old) but only at AA 17-36, 39-48, 93-102, 109-120, 123-132, 139-154, and 159-174 using sera from 8 infants (<3 year old). The epitopes AA 69-78 and AA 173-194, were recognised by 67% and 100% of sera from older children and binding appeared to be predictive of those children who would not out grow their allergy.

  Vila et al. (2001) [1196] reported IgE binding to immobilised synthetic peptides using sera from 10 patients who subsequently out grew their allergy to cow's milk and 10 with persistent (>7 years) allergy. All sera were collected when patients were allergic. Of the allergic children who later became tolerant, none had IgE binding residues 69-78 and only 2/10 had IgE binding strongly to residues 175-192. All who remained allergic had IgE binding to residues 69-78 and/or 175-192 (60% to AA 69-78 and 80% to 175-192).

  These workers (Cocco et al. 2003 [1270]) then explored the effects of mutating individual residues on the binding of IgE to peptides identified earlier using alanine mutagenesis and pooled sera from 15 cow's milk allergic patients. Binding to epitope 17-30 was dramatically reduced (<25%) by mutations F23A, F24A, V25A, P27A and P29A; binding to epitope 23-36 was reduced by F28A and F32A; binding to epitope 89-102 was reduced by L98A and L95A; binding to epitope 109-120 was abolished by P113A, N114A and E117A; binding to epitope 139-152 was reduced by F145A and Y146A; binding to epitope 159-172 was reduced by L169A and dramatically reduced by Y166A; binding to epitope 173-186 was reduced (<25%) by I182A and significantly by P183A; binding to epitope 179-192 was dramatically reduced by mutations G187A and E189A and abolished by I186A. Double mutation of residues reducing binding abolished binding where tested. However, tests with individual sera although similar revealed a more heterogeneous pattern in IgE recognition.

  Spuergin et al (1997) [1205] identified regions 19-30, 93-98, and 141-150 as immunodominant epitopes using sera from 15 patients with cow's milk allergy and a median age below 3 years, with immobilised synthetic decapeptides. ELISA inhibition experiments show binding to AA 20-31, 86-102, 141-150 (as confirmation) and also showed AA 188-199 binding IgE. Using individual sera showed more heterogeneity in binding patterns.

  2. Using cow's milk derived peptides in addition to synthetic peptides

  Elsayed et al. (2004) [1414] used sera from 18 milk allergic patients and reported that the N- and C-terminal peptides, AA 16-35 and 136-155 showed highest IgE-binding affinity, while AA 1-18 and 181-199 showed high binding to rabbit IgG. This study used both cyanogen bromide fragments and synthetic peptides and thus allows binding to the heavily phosphorylated protein to be observed, which could not be observed with synthetic peptides. In general, longer peptides were found to bind more IgE than short peptides.

  Elsayed et al. (2004) [1421] explored the recognition of cyanogen bromide fragments and synthetic peptides by T-cells from 8 cow's milk allergic individuals. The fragments stimulated T-cells more than the complete molecule. It was also possible to link the response (IL-4 level) to clinical symptoms for some patients.

  Nakajima-Adachi et al (1998) [1407] used ELISA and ELISA inhibition to characterise IgE binding to casein, cyanogen bromide fragments and synthetic peptides. They report that only the region 181-199 bound strongly and consistently to IgE from 9 sera from milk allergic patients with atopic dermatitis (age 0-6 years).

  3. Using cow's milk derived peptides alone.

  Otani and coworkers (Otani et al, 1986 [1641]; Otani et al, 1989 [1640]) reported that the phosphorylated residues 61-123 gave strongest binding to human IgE (and rabbit IgG). Ametani et al. (1987) [1642] reported IgE binding to residues 133-151 (seen as a minor epitope by Otani et al.) but did not find IgE binding to phosphylated peptides.

• Allergen stability:
  Process, chemical, enzymatic:Caseins do not maintain a unique folded conformation (Horne, 2002 [1634]), which has led to them being termed rheomorphic, and are highly sensitive to proteolysis. However, as there is limited folded structure, heating generally does not change the structure and hence its IgE binding (Kohno et al. 1994 [1643]).
• Nature of main cross-reacting proteins:The alpha S1-caseins of goat and sheep are 88% and 85% identical in sequence respectively. Thus cross-reactivity is very likely. Experimentally, IgE cross-reactivity is observed for caseins of buffalo, sheep and goat (Restani et al. 1999 [1624]). The alpha S1-caseins of mare's milk is 47% identical which suggests little cross-reactivity and Businco et al (2000) [1628] report that most cow's milk allergic patients can tolerate mare's milk. The alpha S1-caseins of human milk is 32% identical suggesting that cross-reactivity is improbable. Bernard et al. (2000) [1202] suggest that some unexpected cross-reactivity, such as between bovine alpha and beta caseins, could arise from IgE specific for phosphorylated peptides, which are also more conserved by evolution than the complete sequences between alpha S1-, alpha S2- and beta-caseins.
• Allergen properties & biological function:Alpha s1-casein comprises approximately 40% of the casein fraction of cow's milk (Bernard et al, 1998 [1203]). Sequence variants are known, arising from alternative splicings as well as variant genes (Farrell et al. 2004 [1253]). It is phosphorylated at up to nine positions depending on the genetic variants. Wind et al (2001) [1636] report an average of 8 phosphates per molecule in alpha-casein. Golgi protein kinase is specific for sequences such as SXE and the E may be replaced by a D or a phosphorylated residue. This causes phosphorylation sites to be grouped. Phosphorylation of bovine alpha s1-casein is also concentrated in the central more hydrophilic region of the sequence (McCormick et al. 2005 [1639]). This leads to tight binding of calcium described as nanoclusters (Symth et al. 2004 [1637]). The caseins are the major source of phosphate for the calf and also bind large quantities of calcium. However, alpha caseins alone precipitate when calcium is added and remain soluble only when present in the casein micellar structure with other caseins.
• Allergen purification:

  Strange et al. (1992) [1493] review the purification of proteins from milk.

  Caseins can be prepared from milk by precipitation at pH 4.6 with acetic acid, centrifuged (2250 x g for 5 minutes) and washed twice with 0.1 M ammonium acetate, pH 4.6 (Rasmussen & Petersen, 1991 [1416]). Individual caseins can then be separated by gel chromatography on a Sepharose CL-6B column or denatured and separated in urea (Rasmussen et al. 1994 [1418]).

  Elsayed et al. (2004) [1414] started from commercial alpha s1-casein and used gel filtration followed by RP/HPLC performed using a 130A Separation System (Brownlee^TMC18) with Aquapore RP-300 7 µm 30 x 2.1 mm cartridges (Applied Biosystems, Foster City, CA, USA). Solvent gradient used was 0.1% trifluoroacetic acid in 70% acetonitrile for 30 minutes at a flow rate of 200 µl/m.

• Other biochemical information:

  Natale et al. (2004) [1409] found that 55% of 20 sera from patients aged 4 months to 14 months contained IgE against alpha S1-casein.

References (26)

• Spuergin P, Mueller H, Walter M, Schiltz E, Forster J.
  Allergenic epitopes of bovine alpha S1-casein recognized by human IgE and IgG.
  Allergy 51(5):306-312.. 1996
  PUBMEDID: 8836334
• Spuergin P, Walter M, Schiltz E, Deichmann K, Forster J, Mueller H.
  Allergenicity of alpha-caseins from cow, sheep, and goat.
  Allergy 52(3):293-298.. 1997
  PUBMEDID: 9140519
• Cocco RR, Jarvinen KM, Sampson HA, Beyer K.
  Mutational analysis of major, sequential IgE-binding epitopes in alpha s1-casein, a major cow's milk allergen.
  J Allergy Clin Immunol. 112(2):433-437.. 2003
  PUBMEDID: 12897753
• Chatchatee P, Jarvinen KM, Bardina L, Beyer K, Sampson HA.
  Identification of IgE- and IgG-binding epitopes on alpha(s1)-casein: differences in patients with persistent and transient cow's milk allergy.
  J Allergy Clin Immunol. 107(2):379-383.. 2001
  PUBMEDID: 11174208
• Nakajima-Adachi H, Hachimura S, Ise W, Honma K, Nishiwaki S, Hirota M, Shimojo N, Katsuki T, Ametani A, Kohno Y, Kaminogawa S.
  Determinant analysis of IgE and IgG4 antibodies and T cells specific for bovine alpha(s)1-casein from the same patients allergic to cow's milk: existence of alpha(s)1-casein-specific B cells and T cells characteristic in cow's-milk allergy.
  J Allergy Clin Immunol. 101(5):660-671.. 1998
  PUBMEDID: 9600504
• Elsayed S, Hill DJ, Do TV.
  Evaluation of the allergenicity and antigenicity of bovine-milk alphas1-casein using extensively purified synthetic peptides.
  Scand J Immunol. 60(5):486-493.. 2004
  PUBMEDID: 15541041
• Creamer LK, Richardson T.
  Anomalous behavior of bovine alpha s1- and beta-caseins on gel electrophoresis in sodium dodecyl sulfate buffers.
  Arch Biochem Biophys. 234(2):476-486.. 1984
  PUBMEDID: 6497382
• Rasmussen LK, Petersen TE.
  Purification of disulphide-linked alpha s2- and kappa-casein from bovine milk.
  J Dairy Res. 58(2):187-193.. 1991
  PUBMEDID: 1856353
• Rasmussen LK, Hojrup P, Petersen TE.
  Disulphide arrangement in bovine caseins: localization of intrachain disulphide bridges in monomers of kappa- and alpha s2-casein from bovine milk.
  J Dairy Res. 61(4):485-493.. 1994
  PUBMEDID: 7829753
• Vila L, Beyer K, Jarvinen KM, Chatchatee P, Bardina L, Sampson HA.
  Role of conformational and linear epitopes in the achievement of tolerance in cow's milk allergy.
  Clin Exp Allergy. 31(10):1599-1606.. 2001
  PUBMEDID: 11678861
• Bernard H, Meisel H, Creminon C, Wal JM.
  Post-translational phosphorylation affects the IgE binding capacity of caseins.
  FEBS Lett. 467(2-3):239-244.. 2000
  PUBMEDID: 10675546
• Bernard H, Creminon C, Yvon M, Wal JM.
  Specificity of the human IgE response to the different purified caseins in allergy to cow's milk proteins.
  Int Arch Allergy Immunol. 115(3):235-244.. 1998
  PUBMEDID: 9531166
• Elsayed S, Eriksen J, Oysaed LK, Idsoe R, Hill DJ.
  T cell recognition pattern of bovine milk alphaS1-casein and its peptides.
  Mol Immunol. 41(12):1225-1234.. 2004
  PUBMEDID: 15482858
• Horne DS
  Casein structure, self-assembly and gelation
  CURRENT OPINION IN COLLOID & INTERFACE SCIENCE 7 (5-6): 456-461. 2002
  PUBMEDID:
• Wind M, Wesch H, Lehmann WD.
  Protein phosphorylation degree: determination by capillary liquid chromatography and inductively coupled plasma mass spectrometry.
  Anal Chem. 73(13):3006-3010. . 2001
  PUBMEDID: 11467547
• Smyth E, Clegg RA, Holt C
  A biological perspective on the structure and function of caseins and casein micelles
  International Journal of Dairy Technology 57 (2-3): 121-126. 2004
  PUBMEDID:
• McCormick DJ, Holmes MW, Muddiman DC, Madden BJ.
  Mapping sites of protein phosphorylation by mass spectrometry utilizing a chemical-enzymatic approach: characterization of products from alpha-S1 casein phosphopeptides.
  J Proteome Res. 4(2):424-434.. 2005
  PUBMEDID: 15822919
• Restani P, Gaiaschi A, Plebani A, Beretta B, Cavagni G, Fiocchi A, Poiesi C, Velona T, Ugazio AG, Galli CL.
  Cross-reactivity between milk proteins from different animal species.
  Clin Exp Allergy. 29(7):997-1004.. 1999
  PUBMEDID: 10383602
• Businco L, Giampietro PG, Lucenti P, Lucaroni F, Pini C, Di Felice G, Iacovacci P, Curadi C, Orlandi M.
  Allergenicity of mare's milk in children with cow's milk allergy.
  J Allergy Clin Immunol. 105(5):1031-1034.. 2000
  PUBMEDID: 10808187
• Otani H, Dong XY, Hara T, Kobayashi M, Kayahara H, Hosono A.
  Specificities to cow milk-proteins of human-serum antibodies from clinically allergic patients.
  Milchwissenschaft-Milk Science International 44 (5): 267-270. 1989
  PUBMEDID:
• Otani H; Takahashi F; Tokita F.
  Antigenic reactivities of fragments obtained by cyanogen-bromide cleavage of bovine alpha-S1-casein toward antiserum to intact alpha-S1-casein.
  Agricultural and Biological Chemistry 50(3), 607-613. 1986
  PUBMEDID:
• Ametani A; Kaminogawa S; Shimizu M; Yamauchi K.
  Rapid screening of antigenically reactive fragments of alpha-S1-casein using HPLC and ELISA.
  Journal of Biochemistry 102(2), 421-425. 1987
  PUBMEDID:
• Kohno Y, Honma K, Saito K, Shimojo N, Tsunoo H, Kaminogawa S, Niimi H.
  Preferential recognition of primary protein structures of alpha-casein by IgG and IgE antibodies of patients with milk allergy.
  Ann Allergy 73(5):419-422.. 1994
  PUBMEDID: 7978534
• Farrell HM Jr, Jimenez-Flores R, Bleck GT, Brown EM, Butler JE, Creamer LK, Hicks CL, Hollar CM, Ng-Kwai-Hang KF, Swaisgood HE.
  Nomenclature of the proteins of cows' milk--sixth revision.
  J Dairy Sci. 87(6):1641-1674.. 2004
  PUBMEDID: 15453478
• Strange ED, Malin EL, Van Hekken DL, Basch JJ.
  Chromatographic and electrophoretic methods used for analysis of milk proteins.
  J Chromatogr. 624(1-2):81-102.. 1992
  PUBMEDID: 1494022
• Natale M, Bisson C, Monti G, Peltran A, Garoffo LP, Valentini S, Fabris C, Bertino E, Coscia A, Conti A.
  Cow's milk allergens identification by two-dimensional immunoblotting and mass spectrometry.
  Mol Nutr Food Res. 48(5):363-369.. 2004
  PUBMEDID: 15672476

Biochemical Information for Alpha S2-Casein

• Allergen Name:Alpha S2-Casein
• Alternatve Allergen Names:Bos d 8 (name for all caseins)
• Allergen Designation:Major
• Protein Family:Pfam PF00363; Casein
• Sequence Known?:Yes
• Allergen accession No.s:http://us.expasy.org/cgi-bin/niceprot.pl?P02663
• 3D Structure Accession No.:N/A
• Calculated Masses:

  24348 Da (without signal or phosphates)

  26019 Da (precursor)

• Experimental Masses:27-32 kDa depending on conditions (Creamer & Richardson, 1984 [1417] noted that caseins run slowly under SDS-PAGE)
• Oligomeric Masses:

  Caseins form stable micellar calcium phosphate protein complexes. However, large aggregates are also reported.

• Allergen epitopes:

  Busse et al. (2002) [1191] used 99 synthetic decapeptides synthesised on a SPOTs membrane (Genosys Biotechnologies, Inc, Woodlands, Texas) and IgE binding was detected with biotinylated goat or mouse anti-human IgE and a peroxidase streptavidin conjugate. They identified 10 regions binding IgE from the sera 13 patients (median age 8 years). Residues 31-44, 43-56, 83-100, 93-108, 105-114, 117-128, 143-158, 157-172, 165-188 and 191-200 were recognised by IgE from sera of 6/13, 4/13, 12/13, 5/13, 3/13, 3/13, 10/13, 11/13, 11/13 and 4/13 cow's milk allergic individuals respectively.

  Järvinen et al. (2002) [1192] used the same techniques and reported binding of IgE from sera of individuals with persistent cow's milk allergy to residues 33-42, 87-96 and 159-168 with weak binding to 145-154 and 171-180. Patients with transient allergy showed only weak binding to alpha S2-casein peptides.

  Bernard et al. (2000) [1202] reported that IgE binding to alpha s2-casein could be partially or completely inhibited by two variants of dephosphorylated alpha s2-caseins but with different efficiencies. Variant A always appears a better competitor than variant D. Totally dephosphorylated alpha s2-casein required very high concentrations to inhibit IgE binding. These data indicate that some of the phosphorylated regions, residues 23-31, 73-76 and 144-146, form part of the IgE epitopes and that the phosphates are involved in antibody recognition.

• Allergen stability:
  Process, chemical, enzymatic:Caseins do not maintain a unique folded conformation (Horne, 2002 [1634]), which has led to them being termed rheomorphic, and are highly sensitive to proteolysis. However, alpha-s2 casein does possess approx 25% alpha-helix. Alpha S2 casein contains 3 cysteines and forms disulphide-linked dimers. However, as there is limited folded structure, heating generally does not change the structure and hence its IgE binding (Kohno et al. 1994 [1643]).
• Nature of main cross-reacting proteins:The alpha S2-caseins of goat and sheep are 87% and 89% identical in sequence respectively. Thus cross-reactivity is very likely. Experimentally, IgE cross-reactivity is observed for caseins of buffalo, sheep and goat (Restani et al. 1999 [1624]). Bernard et al. (2000) [1202] suggest that some unexpected cross-reactivity, such as between alpha and beta caseins, could arise from IgE specific for phosphorylated peptides, which are also more conserved by evolution than the complete sequences between alpha S1-, alpha S2- and beta-caseins.
• Allergen properties & biological function:Bovine alpha s2-casein comprises approximately 10% of the casein fraction of cow's milk (Bernard et al, 1998 [1203]). Sequence variants are known, arising from alternative splicings as well as variant genes (Farrell et al. 2004 [1253]). Alpha s2-casein is phosphorylated at multiple sites. The caseins are the major source of phosphate for the calf and also bind large quantities of calcium. However, alpha caseins alone precipitate when calcium is added and remain soluble only when present in the casein micellar structure with other caseins.
• Allergen purification:

  Caseins can be prepared from milk by precipitation at pH 4.6 with acetic acid, centrifuged (2250 x g for 5 minutes) and washed twice with 0.1 M ammonium acetate, pH 4.6 (Rasmussen & Petersen, 1991 [1416]). Individual caseins can then be separated by gel chromatography on a Sepharose CL-6B column or denatured and separated in urea (Rasmussen et al. 1992 [1419]).
  A complexity is that the different variants depend on the genetics of the cows. Bernard et al (2000) [1202] prepared variants A and D of alpha s2-casein from fresh milk samples of cows that were homozygous for these variants. For example, casein containing alpha s2-casein variant D was obtained by precipitation at pH 4.6 and selectively fractionated by addition of 40% propanol-1 at 4°C. After 2 h of slight agitation, the mixture was centrifuged at 17000 rpm for 30 min at 4°C. The supernatant was discarded and the precipitate was solubilized in 6 M urea, dialyzed against water adjusted to pH 7.0 with NaOH, and lyophilized. Purification was achieved using a MonoQ anion exchange system.

  Strange et al. (1992) [1493] review the purification of proteins from milk.

• Other biochemical information:

  Natale et al. (2004) [1409] found that 90% of 20 patients aged 4 months to 14 months had serum IgE against alpha S2-casein.

  Human milk does not contain an alpha S2-casein as the gene is truncated after 27 residues. Alpha S2-caseins occur in mare's milk (Miranda et al. 2004 [1426]) but the sequence has not been reported.

References (14)

• Busse PJ, Järvinen KM, Vila L, Beyer K, Sampson HA.
  Identification of sequential IgE-binding epitopes on bovine alpha(s2)-casein in cow's milk allergic patients.
  Int Arch Allergy Immunol. 129(1):93-96.. 2002
  PUBMEDID: 12373003
• Bernard H, Meisel H, Creminon C, Wal JM.
  Post-translational phosphorylation affects the IgE binding capacity of caseins.
  FEBS Lett. 467(2-3):239-244.. 2000
  PUBMEDID: 10675546
• Rasmussen LK, Hojrup P, Petersen TE.
  The multimeric structure and disulfide-bonding pattern of bovine kappa-casein.
  Eur J Biochem. 207(1):215-222.. 1992
  PUBMEDID: 1628650
• Bernard H, Creminon C, Yvon M, Wal JM.
  Specificity of the human IgE response to the different purified caseins in allergy to cow's milk proteins.
  Int Arch Allergy Immunol. 115(3):235-244.. 1998
  PUBMEDID: 9531166
• Järvinen KM, Beyer K, Vila L, Chatchatee P, Busse PJ, Sampson HA.
  B-cell epitopes as a screening instrument for persistent cow's milk allergy.
  J Allergy Clin Immunol. 110(2):293-297.. 2002
  PUBMEDID: 12170271
• Miranda G, Mahe MF, Leroux C, Martin P.
  Proteomic tools to characterize the protein fraction of Equidae milk.
  Proteomics 4(8):2496-2509.. 2004
  PUBMEDID: 15274143
• Strange ED, Malin EL, Van Hekken DL, Basch JJ.
  Chromatographic and electrophoretic methods used for analysis of milk proteins.
  J Chromatogr. 624(1-2):81-102.. 1992
  PUBMEDID: 1494022
• Kohno Y, Honma K, Saito K, Shimojo N, Tsunoo H, Kaminogawa S, Niimi H.
  Preferential recognition of primary protein structures of alpha-casein by IgG and IgE antibodies of patients with milk allergy.
  Ann Allergy 73(5):419-422.. 1994
  PUBMEDID: 7978534
• Horne DS
  Casein structure, self-assembly and gelation
  CURRENT OPINION IN COLLOID & INTERFACE SCIENCE 7 (5-6): 456-461. 2002
  PUBMEDID:
• Creamer LK, Richardson T.
  Anomalous behavior of bovine alpha s1- and beta-caseins on gel electrophoresis in sodium dodecyl sulfate buffers.
  Arch Biochem Biophys. 234(2):476-486.. 1984
  PUBMEDID: 6497382
• Restani P, Gaiaschi A, Plebani A, Beretta B, Cavagni G, Fiocchi A, Poiesi C, Velona T, Ugazio AG, Galli CL.
  Cross-reactivity between milk proteins from different animal species.
  Clin Exp Allergy. 29(7):997-1004.. 1999
  PUBMEDID: 10383602
• Farrell HM Jr, Jimenez-Flores R, Bleck GT, Brown EM, Butler JE, Creamer LK, Hicks CL, Hollar CM, Ng-Kwai-Hang KF, Swaisgood HE.
  Nomenclature of the proteins of cows' milk--sixth revision.
  J Dairy Sci. 87(6):1641-1674.. 2004
  PUBMEDID: 15453478
• Rasmussen LK, Petersen TE.
  Purification of disulphide-linked alpha s2- and kappa-casein from bovine milk.
  J Dairy Res. 58(2):187-193.. 1991
  PUBMEDID: 1856353
• Natale M, Bisson C, Monti G, Peltran A, Garoffo LP, Valentini S, Fabris C, Bertino E, Coscia A, Conti A.
  Cow's milk allergens identification by two-dimensional immunoblotting and mass spectrometry.
  Mol Nutr Food Res. 48(5):363-369.. 2004
  PUBMEDID: 15672476

Biochemical Information for Alpha-Lactalbumin

• Allergen Name:Alpha-Lactalbumin
• Alternatve Allergen Names:Bos d 4, Lactose synthase B protein
• Allergen Designation:Minor
• Protein Family:Alpha-lactalbumin is a homologue of the C-type lysozymes. It is a member of glycohydrolyase family 22 and Pfam family PF00062.
• Sequence Known?:Yes
• Allergen accession No.s:http://us.expasy.org/cgi-bin/niceprot.pl?P00711
• 3D Structure Accession No.:

  1F6R (apo without calcium)
  1F6S (holo with calcium)
  1HFZ (Recombinant holo with N-terminal methionine and M90V)

• Calculated Masses:14186 (mature protein only)
• Experimental Masses:14 178 Da (unglycosylated form with disulphides)
  15 840 to 16 690 Da (glycosylated)
• Oligomeric Masses:Monomer or part of the lactose synthase complex
• Allergen epitopes:

  Järvinen et al (2001) [1195] used sera from 11 patients 4-18 years of age with persistent allergy and IgE to cow's milk >100 kU(A)/l together with 57 overlapping synthetic decapeptides to identify linear epitopes. IgE from the sera bound most strongly to residues 1-16, 13-26, 47-58 and 93-102 with serum IgE from 7/11, 5/11, 3/11 and 3/11 allergic patients binding to these peptides; other regions were recognised by IgE from at most a single individual.

  Maynard et al (1997) [1434] used sera from 19 patients allergic to cow's milk with 0.6-125 IU/ml of specific IgE against alpha-lactalbumin to investigate the binding of IgE to native and reduced tryptic peptides. 60% of the sera were specific for the intact alpha-lactalbumin with only 40% binding to the peptides. In some of the reactive sera, the binding to peptides was strongly reduced but others appeared to bind to linear epitopes and showed similar binding to the peptides as to the protein allergen. Most of the peptides were recognised by IgE from some sera. Residues 17-58 were most frequently recognised. Residues 59-93, 99-108 and 109-123 were also recognised. It was suggested that IgE binding did not correspond to IgG epitopes previously predicted from the sequence.

• Allergen stability:
  Process, chemical, enzymatic:

  Polverino de Laureto et al (2002) [1303] have reported that alpha-lactalbumin is cleaved by pepsin at pH 2 in the region of residues 34-57, producing large fragments.

  Alpha-lactalbumin is stabilized by binding to calcium. Veprintsev et al. (1997) [1644] report that DSC of alpha-lactalbumin at pH 8.1 showed transitions at 20-30°C with the calcium chelator EGTA and near 70°C with added calcium. McGuffey et al. (2005) [1467] investigated the effects of heating purified alpha-lactalbumin and show that the extent of irreversible aggregation varies with the conditions between 67°C and 95°C. When milk is heated to 95°C, alpha-lactalbumin denatures more slowly than beta-lactoglobulin (Chen et al. 2005 [1466]).

  Alpha-lactalbumin's folded structure is destabilized at low pH with the formation of a molten globule (Redfield, 2004 [1442]).

  The stability to denaturation is also strongly reduced by reduction of the disulphides (Chang, 2004 [1444]). Disulphide exchange can occur during thermal denaturation leading to formation of aggregates (Livney et al, 2003 [1445]).

• Nature of main cross-reacting proteins:

  IgE cross reactivity has been investigated by Maynard et al. (1999) [1463] who found specific IgE binding to human alpha-lactalbumin with all 20 sera. Binding was always lower than with bovine but often comparable with binding to reduced bovine. Binding appeared to involve IgEs with lower affinity suggesting that it might not be clinically relevant. The authors note that no cases of anaphylaxis to the human protein had been reported.

  More surprisingly, Adams et al. (1991) [1435] have described cross-reactivity between alpha-lactalbumin and beta-lactoglobulin. Baroglio et al. (1998) [1465] suggest that this is due to short peptide matches.

• Allergen properties & biological function:

  Although evolved from a lysozyme (Mckenzie, 1996 [1450]), the function of alpha-lactalbumin is to form a complex with galactosyltransferase, altering its substrate specificity to increase the rate of lactose formation in milk synthesis. The complex of galactosyltransferase and alpha-lactalbumin is called lactose synthase (Ramakrishnan & Qasba, 2001 [1451]). Alpha-lactalbumin alone does not have any catalytic activity as a lysozyme or a synthase.

  Several other properties of alpha-lactalbumin and possible additional functions have been described (Permyakov & Berliner, 2000) [1462] including binding of several ligands and antimicrobiol activity both as the complete molecule (Hakansson et al. 2000 [1460]) and as peptides (Pellegrini et al. 1999 [1458]). The cytotoxic effects against mammalian cells have also been investigated (Permyakov et al. 2004 [1461]).

  The major component of alpha-lactalbumin is unglycosylated. However, there is a minor glycosylated form (ca. 10%) with a mass spectrum which contained at least 15 discrete peaks (Slangen and Visser, 1999 [1456]). These arise from glycosylation of asparagine 45.

• Allergen purification:Most studies use commercially purified alpha-lactalbumin, sometimes after repurification by chromatography. Hahn et al. (2003) [1452] and Pedersen et al. (2003) [1453] compare the efficiency of ion-exchange and hydrophobic interaction chromatography using whey proteins as models.

  Xe et al. (2000) [1455] describe the preparation of 1260 mg alpha-lactalbumin, 1290 mg beta-lactoglobulin B and 2280 mg beta-lactoglobulin A from 1L of rennet whey. Alpha-Lactalbumin and beta-lactoglobulin were adsorbed onto quaternary aminoethyl-Toyopearl and alpha-Lactalbumin was eluted using a linear (0-0.15 M) concentration gradient of NaCl in 0.05 M Tris-HCl buffer (pH 8.5).

  Neyestani et al. (2003) [1454] describe a low cost purification of alpha-lactalbumin by ion-exchange chromatography.

  Slangen and Visser (1999) [1456] used gel filtration to obtain both glycosylated and unglycosylated alpha-lactalbumin.

  Wang et al. (1989) [1457] produced recombinant bovine alpha-lactalbumin in E. coli.

  Strange et al. (1992) [1493] review the purification of proteins from milk.

• Other biochemical information:

  Because of its combination of easy availability, small size with two domains and relatively complex possible conformations (folded calcium complex, folded apo, molten glubule, detergent complex and amyloid formation), alpha-lactabumin folding and structure has been extensively studied by a wide range of techniques (Redfield, 2004 [1442]; Smith, 2004 [1443]; Chang, 2004 [1444]; Engel et al, 2004 [1447]; Huppertz et al, 2004 [1449]; Livney et al, 2003 [1445]; Engel et al, 2002 [1446]).

  There are several very different estimates of the importance of alpha-lactalbumin as an allergen. Adams et al. (1991) [1435] report that 75% of sera contained alpha-lactalbumin specific IgE. Docena et al. (1996) [1408] report that 5/80 cow's milk allergic individuals had alpha-lactalbumin specific IgE. Natale et al. (2004) [1409] report no individual with alpha-lactalbumin specific IgE out of 20 with cow's milk allergy. It is possible that the requirement for conformational epitopes could account for absence of binding in immunoblotting studies.

  The alpha-lactalbumins of sheep and goat are 97% and 95% identical in sequence, implying IgE cross-reactivity. Human alpha-lactalbumin is 73% identical.

References (31)

• Järvinen KM, Chatchatee P, Bardina L, Beyer K, Sampson HA.
  IgE and IgG binding epitopes on alpha-lactalbumin and beta-lactoglobulin in cow's milk allergy.
  Int Arch Allergy Immunol. 126(2):111-118. . 2001
  PUBMEDID: 11729348
• Redfield C.
  NMR studies of partially folded molten-globule states.
  Methods Mol Biol. 278:233-254.. 2004
  PUBMEDID: 15317999
• Smith LJ.
  Computational methods for generating models of denatured and partially folded proteins.
  Methods 34(1):144-150.. 2004
  PUBMEDID: 15283923
• Chang JY.
  Evidence for the underlying cause of diversity of the disulfide folding pathway.
  Biochemistry 43(15):4522-4529.. 2004
  PUBMEDID: 15078098
• Livney YD, Verespej E, Dalgleish DG.
  Steric effects governing disulfide bond interchange during thermal aggregation in solutions of beta-lactoglobulin B and alpha-lactalbumin.
  J Agric Food Chem. 31;51(27):8098-8106.. 2003
  PUBMEDID: 14690403
• Engel MF, van Mierlo CP, Visser AJ.
  Kinetic and structural characterization of adsorption-induced unfolding of bovine alpha -lactalbumin.
  J Biol Chem. 277(13):10922-10930.. 2002
  PUBMEDID: 11782453
• Engel MF, Visser AJ, van Mierlo CP.
  Conformation and orientation of a protein folding intermediate trapped by adsorption.
  Proc Natl Acad Sci U S A. 101(31):11316-21.. 2004
  PUBMEDID: 15263072
• Huppertz T, Fox PF, Kelly AL.
  High pressure-induced denaturation of alpha-lactalbumin and beta-lactoglobulin in bovine milk and whey: a possible mechanism.
  J Dairy Res. 71(4):489-495.. 2004
  PUBMEDID: 15605716
• Maynard F, Jost R, Wal JM.
  Human IgE binding capacity of tryptic peptides from bovine alpha-lactalbumin.
  Int Arch Allergy Immunol. 113(4):478-488.. 1997
  PUBMEDID: 9250594
• McKenzie HA.
  alpha-Lactalbumins and lysozymes.
  EXS. 75:365-409. . 1996
  PUBMEDID: 8765309
• Ramakrishnan B, Qasba PK.
  Crystal structure of lactose synthase reveals a large conformational change in its catalytic component, the beta1,4-galactosyltransferase-I.
  J Mol Biol. 310(1):205-218.. 2001
  PUBMEDID: 11419947
• Hahn R, Deinhofer K, Machold C, Jungbauer A.
  Hydrophobic interaction chromatography of proteins. II. Binding capacity, recovery and mass transfer properties.
  J Chromatogr B Analyt Technol Biomed Life Sci. 790(1-2): 99-114.. 2003
  PUBMEDID: 12767324
• Pedersen L, Mollerup J, Hansen E, Jungbauer A.
  Whey proteins as a model system for chromatographic separation of proteins.
  J Chromatogr B Analyt Technol Biomed Life Sci. 790(1-2): 161-73.. 2003
  PUBMEDID: 12767329
• Neyestani TR, Djalali M, Pezeshki M.
  Isolation of alpha-lactalbumin, beta-lactoglobulin, and bovine serum albumin from cow's milk using gel filtration and anion-exchange chromatography including evaluation of their antigenicity.
  Protein Expr Purif. 29(2):202-208. . 2003
  PUBMEDID: 12767810
• Ye X, Yoshida S, Ng TB.
  Isolation of lactoperoxidase, lactoferrin, alpha-lactalbumin, beta-lactoglobulin B and beta-lactoglobulin A from bovine rennet whey using ion exchange chromatography.
  Int J Biochem Cell Biol. 32(11-12):1143-50. . 2000
  PUBMEDID: 11137454
• Slangen CJ, Visser S.
  Use of mass spectrometry To rapidly characterize the heterogeneity of bovine alpha-lactalbumin.
  J Agric Food Chem. 47(11):4549-4556.. 1999
  PUBMEDID: 10552849
• Wang M, Scott WA, Rao KR, Udey J, Conner GE, Brew K.
  Recombinant bovine alpha-lactalbumin obtained by limited proteolysis of a fusion protein expressed at high levels in Escherichia coli.
  J Biol Chem. 264(35):21116-21121.. 1989
  PUBMEDID: 2687274
• Pellegrini A, Thomas U, Bramaz N, Hunziker P, von Fellenberg R.
  Isolation and identification of three bactericidal domains in the bovine alpha-lactalbumin molecule.
  Biochim Biophys Acta. 1426(3):439-448.. 1999
  PUBMEDID: 10076060
• Hakansson A, Svensson M, Mossberg AK, Sabharwal H, Linse S, Lazou I, Lonnerdal B, Svanborg C.
  A folding variant of alpha-lactalbumin with bactericidal activity against Streptococcus pneumoniae.
  Mol Microbiol. 35(3):589-600.. 2000
  PUBMEDID: 10672181
• Permyakov SE, Pershikova IV, Khokhlova TI, Uversky VN, Permyakov EA.
  No need to be HAMLET or BAMLET to interact with histones: binding of monomeric alpha-lactalbumin to histones and basic poly-amino acids.
  Biochemistry 43(19):5575-5582.. 2004
  PUBMEDID: 15134431
• Permyakov EA, Berliner LJ.
  alpha-Lactalbumin: structure and function.
  FEBS Lett. 473(3):269-274.. 2000
  PUBMEDID: 10818224
• Strange ED, Malin EL, Van Hekken DL, Basch JJ.
  Chromatographic and electrophoretic methods used for analysis of milk proteins.
  J Chromatogr. 624(1-2):81-102.. 1992
  PUBMEDID: 1494022
• Polverino de Laureto P, Frare E, Gottardo R, Van Dael H, Fontana A.
  Partly folded states of members of the lysozyme/lactalbumin superfamily: a comparative study by circular dichroism spectroscopy and limited proteolysis.
  Protein Sci. 11(12):2932-2946.. 2002
  PUBMEDID: 12441391
• Veprintsev DB, Permyakov SE, Permyakov EA, Rogov VV, Cawthern KM, Berliner LJ.
  Cooperative thermal transitions of bovine and human apo-alpha-lactalbumins: evidence for a new intermediate state.
  FEBS Lett. 412(3):625-628.. 1997
  PUBMEDID: 9276479
• Adams SL, Barnett D, Walsh BJ, Pearce RJ, Hill DJ, Howden ME.
  Human IgE-binding synthetic peptides of bovine beta-lactoglobulin and alpha-lactalbumin. In vitro cross-reactivity of the allergens.
  Immunol Cell Biol. 69 ( Pt 3):191-197.. 1991
  PUBMEDID: 1720415
• Baroglio C, Giuffrida MG, Cantisani A, Napolitano L, Bertino E, Fabris C, Conti A.
  Evidence for a common epitope between bovine alpha-lactalbumin and beta-lactoglobulin.
  Biol Chem. 379(12):1453-1456.. 1998
  PUBMEDID: 9894814
• McGuffey MK, Epting KL, Kelly RM, Foegeding EA.
  Denaturation and aggregation of three alpha-lactalbumin preparations at neutral pH.
  J Agric Food Chem. 53(8):3182-3190.. 2005
  PUBMEDID: 15826076
• Chen WL, Hwang MT, Liau CY, Ho JC, Hong KC, Mao SJ.
  Beta-lactoglobulin is a thermal marker in processed milk as studied by electrophoresis and circular dichroic spectra.
  J Dairy Sci. 88(5):1618-1630.. 2005
  PUBMEDID: 15829652
• Maynard F, Chatel J-M, Wal J-M.
  Immunological IgE cross-reactions of bovine and human alpha-lactalbumins in cow's milk allergic patients.
  Food and Agricultural Immunology 11 (2) 179-189.. 1999
  PUBMEDID:
• Docena GH, Fernandez R, Chirdo FG, Fossati CA.
  Identification of casein as the major allergenic and antigenic protein of cow's milk.
  Allergy 51(6):412-416.. 1996
  PUBMEDID: 8837665
• Natale M, Bisson C, Monti G, Peltran A, Garoffo LP, Valentini S, Fabris C, Bertino E, Coscia A, Conti A.
  Cow's milk allergens identification by two-dimensional immunoblotting and mass spectrometry.
  Mol Nutr Food Res. 48(5):363-369.. 2004
  PUBMEDID: 15672476

Biochemical Information for Beta-Casein

• Allergen Name:Beta-Casein
• Alternatve Allergen Names:Bos d 8 (name for all caseins)
• Allergen Designation:
• Protein Family:Pfam PF00363; Casein
• Sequence Known?:Yes
• Allergen accession No.s:

  http://us.expasy.org/cgi-bin/niceprot.pl?P02666

  (Variants AAA30430, AAB29137, AAA30480, AAA30431)

• 3D Structure Accession No.:N/A
• Calculated Masses:

  25107 Da (precursor)
  23982 Da (mature)

• Experimental Masses:26.6 kDa (Creamer & Richardson, 1984 [1417] reported that caseins run more slowly under SDS-PAGE than would be predicted from their calculated mass).
• Oligomeric Masses:

  Caseins form stable micellar calcium phosphate protein complexes. However, large aggregates are also reported.

• Allergen epitopes:

  Chatchatee et al. (2001) [1197] used 100 overlapping synthetic decapeptides to identify residues 1-16, 45-54, 55-70, 83-92, 107-120, 135-144, 149-164, 167-184 and 185-208 as the regions binding to IgE from sera from 15 patients with persistent cow's milk allergy. Sera from 8 younger patients gave a simpler pattern with IgE binding to residues 1-16, 45-54, 83-92, 107-120 and 135-144 with weak binding to residues 57-66 and the C-terminal region.

  Vila et al. (2001) [1196] reported that there was little difference in the IgE binding to beta-casein between cow's milk allergic children who later became tolerant and the 10 who remained allergic, unlike the IgE binding to alpha S1-casein.

  Bernard et al. (2000) [1202] reported that in all 53 sera tested, the IgE response to dephosphorylated beta-casein was lower than that to native beta-casein. In particular, four sera showed no IgE response to dephosphorylated beta-casein while 15 others exhibited a two-fold lower IgE response. These data imply that the N-terminal phosphorylated region, residues 30-50, includes important IgE epitopes.

• Allergen stability:
  Process, chemical, enzymatic:Caseins do not maintain a unique folded conformation (Horne, 2002 [1634]), which has led to them being termed rheomorphic, and are highly sensitive to proteolysis. However, as there is limited folded structure, heating generally does not change the structure and hence its IgE binding.
• Nature of main cross-reacting proteins:IgE cross-reactivity is observed for caseins of buffalo, sheep and goat (Restani et al. 1999 [1624]). Bernard et al. (2000) [1202] suggest that some unexpected cross-reactivity, such as between alpha and beta caseins, could arise from IgE specific for phosphorylated peptides, which are also more conserved by evolution than the complete sequences between alpha S1-, alpha S2- and beta-caseins.
• Allergen properties & biological function:Beta-casein comprises approximately 40% of the casein fraction of cow's milk (Bernard et al, 1998 [1203]). Sequence variants are known due to both partial proteolysis and variant genes (Farrell et al. 2004 [1253]). Beta-casein is less heavily phosphorylated than alpha-caseins with 5 potential phosphoserine sites in the N-terminal part of the sequence. Beta-casein also binds calcium forming "nanoclusters" (Symth et al. 2004 [1637]). The caseins are the major source of phosphate and calcium for the calf.
• Allergen purification:

  Caseins can be prepared from milk by precipitation at pH 4.6 with acetic acid, centrifuged (2250 x g for 5 minutes) and washed twice with 0.1 M ammonium acetate, pH 4.6 (Rasmussen & Petersen, 1991 [1416]). Individual caseins can then be separated by gel chromatography on a Sepharose CL-6B column or denatured and separated in urea (Rasmussen et al. 1994 [1418]).

  Strange et al. (1992) [1493] review the purification of proteins from milk.

• Other biochemical information:

  Natale et al. (2004) [1409] found that 15% of 20 sera from patients aged 4 months to 14 months contained IgE against beta-casein.

  The beta caseins are more conserved than alpha caseins. Thus goat and sheep are 91% identical in sequence and cross-reactivity is very likely. Beta-casein from mare's milk and human milk are 58% and 56% identical respectively suggesting possible cross-reactivity. However, Businco et al (2000) [1628] report that most cow's milk allergic patients can tolerate mare's milk.

References (18)

• Chatchatee P, Jarvinen KM, Bardina L, Vila L, Beyer K, Sampson HA.
  Identification of IgE and IgG binding epitopes on beta- and kappa-casein in cow's milk allergic patients.
  Clin Exp Allergy. 31(8):1256-1262. . 2001
  PUBMEDID: 11529896
• Bernard H, Negroni L, Chatel JM, Clement G, Adel-Patient K, Peltre G, Creminon C, Wal JM.
  Molecular basis of IgE cross-reactivity between human beta-casein and bovine beta-casein, a major allergen of milk.
  Mol Immunol. 37(3-4):161-167. . 2000
  PUBMEDID: 10865115
• Bernard H, Meisel H, Creminon C, Wal JM.
  Post-translational phosphorylation affects the IgE binding capacity of caseins.
  FEBS Lett. 467(2-3):239-244.. 2000
  PUBMEDID: 10675546
• Vila L, Beyer K, Jarvinen KM, Chatchatee P, Bardina L, Sampson HA.
  Role of conformational and linear epitopes in the achievement of tolerance in cow's milk allergy.
  Clin Exp Allergy. 31(10):1599-1606.. 2001
  PUBMEDID: 11678861
• Strange ED, Malin EL, Van Hekken DL, Basch JJ.
  Chromatographic and electrophoretic methods used for analysis of milk proteins.
  J Chromatogr. 624(1-2):81-102.. 1992
  PUBMEDID: 1494022
• Syme CD, Blanch EW, Holt C, Jakes R, Goedert M, Hecht L, Barron LD.
  A Raman optical activity study of rheomorphism in caseins, synucleins and tau. New insight into the structure and behaviour of natively unfolded proteins.
  Eur J Biochem. 269(1):148-156.. 2002
  PUBMEDID: 11784308
• Restani P, Gaiaschi A, Plebani A, Beretta B, Cavagni G, Fiocchi A, Poiesi C, Velona T, Ugazio AG, Galli CL.
  Cross-reactivity between milk proteins from different animal species.
  Clin Exp Allergy. 29(7):997-1004.. 1999
  PUBMEDID: 10383602
• Natale M, Bisson C, Monti G, Peltran A, Garoffo LP, Valentini S, Fabris C, Bertino E, Coscia A, Conti A.
  Cow's milk allergens identification by two-dimensional immunoblotting and mass spectrometry.
  Mol Nutr Food Res. 48(5):363-369.. 2004
  PUBMEDID: 15672476
• Bernard H, Creminon C, Yvon M, Wal JM.
  Specificity of the human IgE response to the different purified caseins in allergy to cow's milk proteins.
  Int Arch Allergy Immunol. 115(3):235-244.. 1998
  PUBMEDID: 9531166
• Farrell HM Jr, Jimenez-Flores R, Bleck GT, Brown EM, Butler JE, Creamer LK, Hicks CL, Hollar CM, Ng-Kwai-Hang KF, Swaisgood HE.
  Nomenclature of the proteins of cows' milk--sixth revision.
  J Dairy Sci. 87(6):1641-1674.. 2004
  PUBMEDID: 15453478
• Smyth E, Clegg RA, Holt C
  A biological perspective on the structure and function of caseins and casein micelles
  International Journal of Dairy Technology 57 (2-3): 121-126. 2004
  PUBMEDID:
• Rasmussen LK, Petersen TE.
  Purification of disulphide-linked alpha s2- and kappa-casein from bovine milk.
  J Dairy Res. 58(2):187-193.. 1991
  PUBMEDID: 1856353
• Rasmussen LK, Hojrup P, Petersen TE.
  Disulphide arrangement in bovine caseins: localization of intrachain disulphide bridges in monomers of kappa- and alpha s2-casein from bovine milk.
  J Dairy Res. 61(4):485-493.. 1994
  PUBMEDID: 7829753
• Taulier N, Chalikian TV.
  Characterization of pH-induced transitions of beta-lactoglobulin: ultrasonic, densimetric, and spectroscopic studies.
  J Mol Biol. 314(4):873-889.. 2001
  PUBMEDID: 11734004
• Creamer LK, Plowman JE, Liddell MJ, Smith MH, Hill JP.
  Micelle stability: kappa-casein structure and function.
  J Dairy Sci. 81(11):3004-3012.. 1998
  PUBMEDID: 9839241
• Businco L, Giampietro PG, Lucenti P, Lucaroni F, Pini C, Di Felice G, Iacovacci P, Curadi C, Orlandi M.
  Allergenicity of mare's milk in children with cow's milk allergy.
  J Allergy Clin Immunol. 105(5):1031-1034.. 2000
  PUBMEDID: 10808187
• Creamer LK, Richardson T.
  Anomalous behavior of bovine alpha s1- and beta-caseins on gel electrophoresis in sodium dodecyl sulfate buffers.
  Arch Biochem Biophys. 234(2):476-486.. 1984
  PUBMEDID: 6497382
• Horne DS
  Casein structure, self-assembly and gelation
  CURRENT OPINION IN COLLOID & INTERFACE SCIENCE 7 (5-6): 456-461. 2002
  PUBMEDID:

Biochemical Information for Beta-Lactoglobulin

• Allergen Name:Beta-Lactoglobulin
• Alternatve Allergen Names:Bos d 5
• Allergen Designation:Major
• Protein Family:Pfam PF00061, Lipocalin
• Sequence Known?:Yes
• Allergen accession No.s:

  http://us.expasy.org/cgi-bin/niceprot.pl?P02754

  There are several variants with the most studied, A and B, differing with 80D and 134V in variant A and 80G and 134A in variant B.

• 3D Structure Accession No.:

  1BEB
  1B8E
  1QG5
  2BLG
  3BLG

• Calculated Masses:

  19883 Da (precursor variant B)

  18281 Da (mature variant B)

• Experimental Masses:18 kDa (Natale et al. 2004) [1409]
• Oligomeric Masses:Under physiological conditions beta-lactoglobulin exists as an equilibrium mixture of monomeric and dimeric forms. Oligomers form below pH 6, the biggest being an octamer being formed around pH 4.6, dissociating below pH 3. Above pH 8, the protein irreversibly denatures, this may lead to aggregation.
• Allergen epitopes:

  Järvinen et al (2001) [1195] synthesised 99 overlapping decapeptides on a SPOTs membrane (Genosys Biotechnologies, Inc, Woodlands, Texas). Sera from 11 patients 4-18 years of age with persistent allergy and IgE to cow's milk >100 kU(A)/l to identify IgE binging mainly to residues 1-16, 31-48, 47-60, 67-78, 75-86, 127-144 and 141-152. Regions 75-86 and 127-144 showed the strongest binding and were recognised by IgE from 10 and 9 sera respectively. 8 patients <3 years of age and likely to outgrow their milk allergy with IgE to cow's milk <30 kU(A)/l were used to investigate the differences in epitope recognition between patients with 'persistent' and those with 'transient' cow's milk allergy. IgE from pooled sera bound to residues 49-60, 119-128, 129-138 and 143-152. It was suggested that the binding to only a few peptides rather than to wide regions of the sequence characterised transient allergy to cow's milk.

  Ball et al. (1994) [1440] identified the region 97-108 as the main linear epitope.

  Adams et al (1991) [1435] showed that residues 124-134 bind 60% of the IgE binding to the complete allergen in a single individual. Binding to this epitope was suggested to lead to cross reactivity with alpha-lactalbumin.

• Allergen stability:
  Process, chemical, enzymatic:

  Ehn et al. (2004) [1432] report that heating beta-lactoglobulin to 74°C and 90°C reduced IgE binding significantly. Heating to 90°C reduced IgE binding more extensively. However, full inhibition was always possible with high concentrations of heated allergen indicating that IgE binding was not completely destroyed.

  Sava et al. (2005) [1468] explored the kinetics of heat-induced structural changes at temperatures ranging from 67.5 to 82.5°C at pH 7.5.

  Chen et al. 2005 [1466] report that there was almost a 90% loss and denaturation of beta-lactoglobulin in processed milk and that this was the major source of protein aggregation. Circular dichroism showed no significant conformational changes at temperatures below 70°C for as long as 480 s. Pronounced and rapid changes occurred between 80 and 95°C in a time-dependent manner. Fifty percent of the maximal changes could be reached within 15 s.

  Guyomarc'h et al. (2003) [1469] report that large micellar aggregates, 4 × 10⁶ Da, are formed on heating milk, which contained 3:1 ratios of beta-lactoglobulin: alpha-lactalbumin together with kappa-casein and alpha S2 casein.

• Nature of main cross-reacting proteins:

  Surprisingly, Adams et al. (1991) [1435] have described cross-reactivity between alpha-lactalbumin and beta-lactoglobulin. Baroglio et al. (1998) [1465] suggest that this is due to short peptide matches. Bertino et al (1996) [1769] reported cross-reaction between polyclonal anti-beta-lactoglobulin and human lactoferrin, beta-casein and alpha-lactalbumin. The most significant cross-reactivity is with the C-terminal part of human beta-casein (Neuteboom et al 1992 [1770]; Conti et al 2000 [1510]). Such cross-reactivities might hinder studies showing that bovine proteins are present in human milk and controversies have developed (Restani et al, 2000 [1511]). However, indirect challenge implies that some bovine proteins are present in human milk (Järvinen et al, 1999 [1512]).

• Allergen properties & biological function:Beta lactoglobulin binds retinol and transport of hydrophobic molecules is probably an important function (Godovac-Zimmermann et al. 1985 [1768]; Kontopidis et al. 2004 [1430]).
• Allergen purification:Most studies use commercially purified beta-lactoglobulin, sometimes after repurification by chromatography. Hahn et al. (2003) [1452] and Pedersen et al. (2003) [1453] compare the efficiency of ion-exchange and hydrophobic interaction chromatography using whey proteins as models.

  Xe et al. (2000) [1455] describe the preparation of 1260 mg alpha-lactalbumin, 1290 mg beta-lactoglobulin B and 2280 mg beta-lactoglobulin A from 1L of rennet whey. Alpha-Lactalbumin and beta-lactoglobulin were adsorbed onto quaternary aminoethyl-Toyopearl and alpha-lactalbumin was eluted using a linear (0-0.15 M) concentration gradient of NaCl in 0.05 M Tris-HCl buffer (pH 8.5). Subsequently, beta-lactoglobulin B and beta-lactoglobulin A were eluted from the column with 0.05 M Tris-HCl (pH 6.8), using a linear (0.1-0.25 M) concentration gradient of NaCl.

  Kim et al. (1997) [1471] have successfully expressed bovine beta-lactoglobulin at a high level in Pichia. Yagi et al (2003) [1470] have expresed mutants in E. coli.

  Strange et al. (1992) [1493] review the purification of proteins from milk.

• Other biochemical information:

  Over the pH range of pH 1 to pH 13, beta lactoglobulin exists in 6 distinct pH-dependent structural states (Taulier & Chalikian, 2001) [1428]. The Tanford transition around pH 7.5 has been especially well characterized as X-ray structures have been determined for these conformations (Qin et al. 1998 [1427]; Oliveira et al. 2001 [1429]). NMR can be used to characterize the low pH monomeric forms (Kuwata et al. 1999 [1433]).

  Natale et al. (2004) [1409] found that 45% of 20 sera from cow's milk allergic patients aged 4 months to 14 months contained IgE directed against beta-lactoglobulin.

  The beta-lactoglobins of sheep and goat are 93% and 94% identical in sequence, implying IgE cross-reactivity. Horse beta-lactoglobin is 59% identical. There is no close human equivalent with the most similar human protein only 44% identical and is found in human placenta and not in milk.

References (31)

• Takagi K, Teshima R, Okunuki H, Sawada J.
  Comparative study of in vitro digestibility of food proteins and effect of preheating on the digestion.
  Biol Pharm Bull. 26(7):969-973.. 2003
  PUBMEDID: 12843620
• Järvinen KM, Chatchatee P, Bardina L, Beyer K, Sampson HA.
  IgE and IgG binding epitopes on alpha-lactalbumin and beta-lactoglobulin in cow's milk allergy.
  Int Arch Allergy Immunol. 126(2):111-118. . 2001
  PUBMEDID: 11729348
• Heinzmann A, Blattmann S, Spuergin P, Forster J, Deichmann KA.
  The recognition pattern of sequential B cell epitopes of beta-lactoglobulin does not vary with the clinical manifestations of cow's milk allergy.
  Int Arch Allergy Immunol. 120(4):280-286.. 1999
  PUBMEDID: 10640911
• Duchateau J, Michils A, Lambert J, Gossart B, Casimir G.
  Anti-betalactoglobulin IgG antibodies bind to a specific profile of epitopes when patients are allergic to cow's milk proteins.
  Clin Exp Allergy 28(7):824-833.. 1998
  PUBMEDID: 9720816
• Qin BY, Bewley MC, Creamer LK, Baker HM, Baker EN, Jameson GB.
  Structural basis of the Tanford transition of bovine beta-lactoglobulin.
  Biochemistry 37(40):14014-14023. . 1998
  PUBMEDID: 9760236
• Taulier N, Chalikian TV.
  Characterization of pH-induced transitions of beta-lactoglobulin: ultrasonic, densimetric, and spectroscopic studies.
  J Mol Biol. 314(4):873-889.. 2001
  PUBMEDID: 11734004
• Ye X, Yoshida S, Ng TB.
  Isolation of lactoperoxidase, lactoferrin, alpha-lactalbumin, beta-lactoglobulin B and beta-lactoglobulin A from bovine rennet whey using ion exchange chromatography.
  Int J Biochem Cell Biol. 32(11-12):1143-50. . 2000
  PUBMEDID: 11137454
• Kuwata K, Hoshino M, Forge V, Era S, Batt CA, Goto Y.
  Solution structure and dynamics of bovine beta-lactoglobulin A.
  Protein Sci. 8(11):2541-2545.. 1999
  PUBMEDID: 10595563
• Ehn BM, Ekstrand B, Bengtsson U, Ahlstedt S.
  Modification of IgE binding during heat processing of the cow's milk allergen beta-lactoglobulin.
  J Agric Food Chem. 52(5):1398-1403.. 2004
  PUBMEDID: 14995152
• Bonomi F, Fiocchi A, Frokiaer H, Gaiaschi A, Iametti S, Poiesi C, Rasmussen P, Restani P, Rovere P.
  Reduction of immunoreactivity of bovine beta-lactoglobulin upon combined physical and proteolytic treatment.
  J Dairy Res. 70(1):51-59.. 2003
  PUBMEDID: 12617393
• Iametti S, Rasmussen P, Frokiaer H, Ferranti P, Addeo F, Bonomi F.
  Proteolysis of bovine beta-lactoglobulin during thermal treatment in subdenaturing conditions highlights some structural features of the temperature-modified protein and yields fragments with low immunoreactivity.
  Eur J Biochem. 269(5):1362-1372.. 2002
  PUBMEDID: 11874450
• Strange ED, Malin EL, Van Hekken DL, Basch JJ.
  Chromatographic and electrophoretic methods used for analysis of milk proteins.
  J Chromatogr. 624(1-2):81-102.. 1992
  PUBMEDID: 1494022
• Baroglio C, Giuffrida MG, Cantisani A, Napolitano L, Bertino E, Fabris C, Conti A.
  Evidence for a common epitope between bovine alpha-lactalbumin and beta-lactoglobulin.
  Biol Chem. 379(12):1453-1456.. 1998
  PUBMEDID: 9894814
• Conti A, Giuffrida MG, Napolitano L, Quaranta S, Bertino E, Coscia A, Costa S, Fabris C.
  Identification of the human beta-casein C-terminal fragments that specifically bind to purified antibodies to bovine beta-lactoglobulin.
  J Nutr Biochem. 11(6):332-337.. 2000
  PUBMEDID: 11002129
• Restani P, Gaiaschi A, Plebani A, Beretta B, Velona T, Cavagni G, Poiesi C, Ugazio AG, Galli CL.
  Evaluation of the presence of bovine proteins in human milk as a possible cause of allergic symptoms in breast-fed children.
  Ann Allergy Asthma Immunol. 84(3):353-360.. 2000
  PUBMEDID: 10752922
• Järvinen KM, Mäkinen-Kiljunen S, Suomalainen H.
  Cow's milk challenge through human milk evokes immune responses in infants with cow's milk allergy.
  J Pediatr. 135(4):506-512.. 1999
  PUBMEDID: 10518086
• Kontopidis G, Holt C, Sawyer L.
  Invited review: beta-lactoglobulin: binding properties, structure, and function.
  J Dairy Sci. 87(4):785-796.. 2004
  PUBMEDID: 15259212
• Kim TR, Goto Y, Hirota N, Kuwata K, Denton H, Wu SY, Sawyer L, Batt CA.
  High-level expression of bovine beta-lactoglobulin in Pichia pastoris and characterization of its physical properties.
  Protein Eng. 10(11):1339-1345. . 1997
  PUBMEDID: 9514124
• Adams SL, Barnett D, Walsh BJ, Pearce RJ, Hill DJ, Howden ME.
  Human IgE-binding synthetic peptides of bovine beta-lactoglobulin and alpha-lactalbumin. In vitro cross-reactivity of the allergens.
  Immunol Cell Biol. 69 ( Pt 3):191-197.. 1991
  PUBMEDID: 1720415
• Yagi M, Sakurai K, Kalidas C, Batt CA, Goto Y.
  Reversible unfolding of bovine beta-lactoglobulin mutants without a free thiol group.
  J Biol Chem. 2003 Nov 21;278(47):47009-15.. 2003
  PUBMEDID: 12963719
• Natale M, Bisson C, Monti G, Peltran A, Garoffo LP, Valentini S, Fabris C, Bertino E, Coscia A, Conti A.
  Cow's milk allergens identification by two-dimensional immunoblotting and mass spectrometry.
  Mol Nutr Food Res. 48(5):363-369.. 2004
  PUBMEDID: 15672476
• Ball G, Shelton MJ, Walsh BJ, Hill DJ, Hosking CS, Howden ME.
  A major continuous allergenic epitope of bovine beta-lactoglobulin recognized by human IgE binding.
  Clin Exp Allergy 24(8):758-764. . 1994
  PUBMEDID: 7526967
• Sava N, Van der Plancken I, Claeys W, Hendrickx M.
  The kinetics of heat-induced structural changes of beta-lactoglobulin.
  J Dairy Sci. 88(5):1646-1653.. 2005
  PUBMEDID: 15829655
• Chen WL, Hwang MT, Liau CY, Ho JC, Hong KC, Mao SJ.
  Beta-lactoglobulin is a thermal marker in processed milk as studied by electrophoresis and circular dichroic spectra.
  J Dairy Sci. 88(5):1618-1630.. 2005
  PUBMEDID: 15829652
• Guyomarc'h F, Law AJ, Dalgleish DG.
  Formation of soluble and micelle-bound protein aggregates in heated milk.
  J Agric Food Chem. 51(16):4652-4660.. 2003
  PUBMEDID: 14705892
• Hahn R, Deinhofer K, Machold C, Jungbauer A.
  Hydrophobic interaction chromatography of proteins. II. Binding capacity, recovery and mass transfer properties.
  J Chromatogr B Analyt Technol Biomed Life Sci. 790(1-2): 99-114.. 2003
  PUBMEDID: 12767324
• Pedersen L, Mollerup J, Hansen E, Jungbauer A.
  Whey proteins as a model system for chromatographic separation of proteins.
  J Chromatogr B Analyt Technol Biomed Life Sci. 790(1-2): 161-73.. 2003
  PUBMEDID: 12767329
• Oliveira KM, Valente-Mesquita VL, Botelho MM, Sawyer L, Ferreira ST, Polikarpov I.
  Crystal structures of bovine beta-lactoglobulin in the orthorhombic space group C222(1). Structural differences between genetic variants A and B and features of the Tanford transition.
  Eur J Biochem. 268(2):477-483.. 2001
  PUBMEDID: 11168385
• Godovac-Zimmermann J, Conti A, Liberatori J, Braunitzer G.
  Homology between the primary structures of beta-lactoglobulins and human retinol-binding protein: evidence for a similar biological function?
  Biol Chem Hoppe Seyler. 366(4):431-434.. 1985
  PUBMEDID: 4040765
• Bertino E, Prandi GM, Fabris C, Cavaletto M, Di Martino S, Cardaropoli S, Calderone V, Conti A.
  Human milk proteins may interfere in ELISA measurements of bovine beta-lactoglobulin in human milk.
  Acta Paediatr. 85(5):543-549.. 1996
  PUBMEDID: 8827096
• Neuteboom B, Giuffrida MG, Cantisani A, Napolitano L, Alessandri A, Fabris C, Bertino E, Conti A.
  Human milk components cross-reacting with antibodies against bovine beta-lactoglobulin.
  Acta Paediatr. 81(6-7):469-474.. 1992
  PUBMEDID: 1392355

Biochemical Information for Bos d 7

• Allergen Name:Bos d 7
• Alternatve Allergen Names:Immunoglobulin, immunoglobin
• Allergen Designation:Major
• Protein Family:Immunoglobulin family, Pfam http://www.sanger.ac.uk/cgi-bin/Pfam/getacc?PF00047
• Sequence Known?:Immunoglobulins by their very nature do not possess unique sequences as the complimentary determining regions (CDRs) which form the antibody binding sites are generated by somatic mutation and gene splicing. Representative sequences are given below.
• Allergen accession No.s:

  http://www.ncbi.nlm.nih.gov/entrez/viewer.fcgi?val=XP_593266.1 (bovine light chain)

  http://www.ncbi.nlm.nih.gov/entrez/viewer.fcgi?val=AAB37381.2 (bovine IgG1 heavy chain constant region)

  http://www.ncbi.nlm.nih.gov/entrez/viewer.fcgi?val=AAB37380.1 (bovine IgG2a heavy chain constant region)

  http://www.ncbi.nlm.nih.gov/entrez/viewer.fcgi?val=XP_587538.1 (bovine IgG3 heavy chain constant region)

  http://www.ncbi.nlm.nih.gov/entrez/viewer.fcgi?val=AAC18409.1 (bovine IgG heavy chain variable region fragment)

• 3D Structure Accession No.:N/A
• Calculated Masses:N/A
• Experimental Masses:55 kDa
• Oligomeric Masses:IgG exists as an approximately 160 kDa disuphide-linked tetramer of two heavy and two light chains.
• Allergen epitopes:Not known
• Allergen stability:
  Process, chemical, enzymatic:Li-Chan et al. (1995) [1533] reported that 59-76% of native bovine IgG can be detected after commercial pasteurization (a mild heat treatment of milk such as heating to 72° C for at least 16 sec. followed by rapid cooling).
• Nature of main cross-reacting proteins:

  Not known

• Allergen properties & biological function:

  Immunoglobulins are an important part of the humoral immune system and function by binding specifically to enviromental agents such as viruses, bacteria, foods and toxins.

  Some bovine IgG contains N-acetylgalactosaminylated N-linked sugar chains (Aoki et al. 1995 [1441]).

• Allergen purification:

  Hahn et al. (1998) [1490] describe a partial purification of several whey proteins. Milk was delipidated by centrifugation and casein removed by adjusting to pH 4.7 and centrifugation. The whey was diluted to a conductivity of 2.7 mS/cm, the pH readjusted to 4.7 and then filtered through 0.45-µm membrane. The diluted whey was loaded onto one of 4 cation exchange columns (Macro-Prep High S Support, S-Sepharose Fast Flow, S-HyperD-F and Fractogel EMD SO₃^- 650 (S)) equilibrated with 20 mM citrate buffer at pH 4.7. The majority of IgG could be eluted with 0.1 M NaCl from S-HyperD together with lactoperoxidase activity.

  Xu and Ding (2004) [1488] used heat with isopropyl alcohol to denature and precipitate the proteins from bovine plasma except for BSA and IgG; then, CM-Trisacryl was applied to further purify and isolate BSA and IgG. This gave BSA and IgG in 98% and 96.8% purity with a yielded of 2.18% and 0.54%, respectively.

• Other biochemical information:

  Natale et al. (2004) [1409] found that 95% of 20 sera from cow's milk allergic patients aged 4 months to 14 months contained IgE directed against IgG heavy chain.

  Similarly, Bernhisel-Broadbent et al. (1991) [1306] found that 16 out of 22 milk-hypersensitive patients had specific IgE binding against a bovine immunoglobulin preparation.

  The variability in sequence arises primarily from the CDRs which form the antibody binding sites and is generated as a consequence of somatic mutation and gene splicing bringing together various genes in novel combinations (Early et al, 1980 [1209]; Mayer et al, 1997 [1424]; Farrell et al, 2004 [1253]). Other regions such as the Fc and much of the Fab region have well defined sequences. href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?CMD=Display&DB=protein (GenBank) returns 1582 sequences with "immunoglobulin and taurus" and IMGT http://imgt.cines.fr/cgi-bin/IMGTlect.jv returns 371 sequence with cow. However, not all these sequences are IgGs.

References (9)

• Hahn R, Schulz PM, Schaupp C, Jungbauer A.
  Bovine whey fractionation based on cation-exchange chromatography.
  J Chromatogr A 795(2):277-287.. 1998
  PUBMEDID: 9528103
• Xu Y, Ding Z.
  A novel method for simultaneous purification of albumin and immunoglobulin G.
  Prep Biochem Biotechnol. 34(4):377-385.. 2004
  PUBMEDID: 15553906
• Early P, Huang H, Davis M, Calame K, Hood L.
  An immunoglobulin heavy chain variable region gene is generated from three segments of DNA: VH, D and JH.
  Cell. 19(4):981-992.. 1980
  PUBMEDID: 6769593
• Farrell HM Jr, Jimenez-Flores R, Bleck GT, Brown EM, Butler JE, Creamer LK, Hicks CL, Hollar CM, Ng-Kwai-Hang KF, Swaisgood HE.
  Nomenclature of the proteins of cows' milk--sixth revision.
  J Dairy Sci. 87(6):1641-1674.. 2004
  PUBMEDID: 15453478
• Meyer A, Parng CL, Hansal SA, Osborne BA, Goldsby RA.
  Immunoglobulin gene diversification in cattle.
  Int Rev Immunol. 15(3-4):165-183.. 1997
  PUBMEDID: 9222818
• Aoki N, Furukawa K, Iwatsuki K, Noda A, Sato T, Nakamura R, Matsuda T.
  A bovine IgG heavy chain contains N-acetylgalactosaminylated N-linked sugar chains.
  Biochem Biophys Res Commun. 210(2):275-280.. 1995
  PUBMEDID: 7755601
• Bernhisel-Broadbent J, Yolken RH, Sampson HA.
  Allergenicity of orally administered immunoglobulin preparations in food-allergic children.
  Pediatrics. 87(2):208-214.. 1991
  PUBMEDID: 1987533
• Natale M, Bisson C, Monti G, Peltran A, Garoffo LP, Valentini S, Fabris C, Bertino E, Coscia A, Conti A.
  Cow's milk allergens identification by two-dimensional immunoblotting and mass spectrometry.
  Mol Nutr Food Res. 48(5):363-369.. 2004
  PUBMEDID: 15672476
• Li-Chan, E.; Kummer, A.; Losso, J. N.; Kitts, D. D.; Nakai, S.
  Stability of bovine immunoglobulins to thermal treatment and processing.
  Food Res. Int. 28, 9-16.. 1995
  PUBMEDID:

Biochemical Information for Bovine Serum Albumin

• Allergen Name:Bovine Serum Albumin
• Alternatve Allergen Names:Bos d 6
• Allergen Designation:
• Protein Family:Pfam PF00273; Serum albumin family
• Sequence Known?:Yes
• Allergen accession No.s:http://us.expasy.org/cgi-bin/niceprot.pl?P02769
• 3D Structure Accession No.:N/A
• Calculated Masses:69293 Da (precursor)
• Experimental Masses:66474 and 133029 by electrospray ionization mass spectrometry. The high masses may be due to the ions binding water molecules (Wang et al, 2000 [1485]).
• Oligomeric Masses:Monomer and dimer
• Allergen epitopes:Beretta et al. (2001) [1484] identify the region of residues 524-598 produced by limited proteolysis as binding human IgE and note that 524-542 is the region with strongest binding.

• Allergen stability:
  Process, chemical, enzymatic:

  Bovine serum albumin is stabilised by 17 disulphide bridges. It is relatively stable and Xu & Ding (2004) [1488] in a purification used heat and isopropyl alcohol to denature and precipitate the other plasma proteins except for immunoglobins. However, heating at 75°C and above produces disulphide linked oligomers (Havea et al, 2000 [1492]).

  Restani et al. (2004) [1478] review IgE binding data using sera from beef allergic patients. They note that reduction of the disulphides reduces but does not abolish IgE binding.

  Beretta et al. (2001) [1484] reported that sequential epitopes were able to resist proteolysis for 60 min when BSA was digested in vitro with pepsin at the ratio of enzyme to substrate of 1:120 (w/w).

• Nature of main cross-reacting proteins:Ovine serum albumin is 92% identical in sequence and likely to show IgE cross-reactivity.
• Allergen properties & biological function:

  Serum albumin regulates the colloidal osmotic pressure of blood, binds several cations, and is the principal transporter of fatty acids, hormones and bilirubin that would be otherwise insoluble in plasma. In addition to being the most abundant plasma protein, a low level finds its way into milk.

  Levi & Gonzalez Flecha (2002) [1486] argue that the dimer is non-covalent and need not involve a disulphide link. By contrast, Hunter & Carta (2001) [1487] suggest that the dimer is disuphide linked and can be removed by purification using BRX-Q as anion exchanger.

• Allergen purification:

  Neyestani et al. (2003) [1454] describe a low cost purification starting from whey after removal of casein from defatted milk using hydrochloric acid. Globulins were precipitated by 50% saturated ammonium sulfate. The supernatant was fractionated using ion-exchange on DEAE cellulose. Alpha-lactalbumin and bovine serum albumin co-eluted and were then isolated by Sephadex G-50 gel filtration.

  Xu & Ding (2004) [1488] used heat and isopropyl alcohol to denature and precipitate the other plasma proteins and isolated bovine serum albumin and immunoglobins by chromatography on CM-Trisacryl with 98% and 96.8% purity respectively.

• Other biochemical information:

  Natale et al. (2004) [1409] found that 45% of 20 sera from patients aged 4 months to 14 months with cow's milk allergy contained IgE against bovine serum albumin.

  Martelli et al. (2002) [1479] reviews the link between cow's milk allergy and allergy to meats such as beef. Bovine serum albumin is an important common allergen. However, Werfel et al. (1997) [1626] suggest that its allergenicity is generally destroyed if beef is well cooked.

  The 3-dimension structure of bovine serum albumin has not been determined. However, that of the homologue human serum albumin, with 76% identity, is available both free and complexed with many hydrophobic ligands with PDB code 1hk1.

  Bovine serum albumin residues 126-144 (ABBOS) have been reported to be responsible for the autoimmune reaction directed against pancreatic islet cells causing diabetes (Karjalainen et al, 1992 [1481]). This remains controversial (Knip, 2003 [1483]; Persaud & Barranco-Mendoza, 2004 [1482]) but removal of this epitope as well as IgE binding is often an objective in producing infant formulas.

  Anaphylaxis due to bovine serum albumin has also been reported in a patient injected with cells cultured in fetal calf serum (Mackensen et al, 2000 [1491]).

References (17)

• Restani P, Ballabio C, Cattaneo A, Isoardi P, Terracciano L, Fiocchi A.
  Characterization of bovine serum albumin epitopes and their role in allergic reactions.
  Allergy 59 Suppl 78:21-24.. 2004
  PUBMEDID: 15245352
• Natale M, Bisson C, Monti G, Peltran A, Garoffo LP, Valentini S, Fabris C, Bertino E, Coscia A, Conti A.
  Cow's milk allergens identification by two-dimensional immunoblotting and mass spectrometry.
  Mol Nutr Food Res. 48(5):363-369.. 2004
  PUBMEDID: 15672476
• Martelli A, De Chiara A, Corvo M, Restani P, Fiocchi A.
  Beef allergy in children with cow's milk allergy; cow's milk allergy in children with beef allergy.
  Ann Allergy Asthma Immunol. 89(6 Suppl 1):38-43.. 2002
  PUBMEDID: 12487203
• Restani P, Beretta B, Fiocchi A, Ballabio C, Galli CL.
  Cross-reactivity between mammalian proteins.
  Ann Allergy Asthma Immunol. 89(6 Suppl 1):11-15.. 2002
  PUBMEDID: 12487198
• Hidvegi E, Cserhati E, Kereki E, Savilahti E, Arato A.
  Serum immunoglobulin E, IgA, and IgG antibodies to different cow's milk proteins in children with cow's milk allergy: association with prognosis and clinical manifestations.
  Pediatr Allergy Immunol. 13(4):255-261.. 2002
  PUBMEDID: 12390441
• Karjalainen J, Martin JM, Knip M, Ilonen J, Robinson BH, Savilahti E, Akerblom HK, Dosch HM.
  A bovine albumin peptide as a possible trigger of insulin-dependent diabetes mellitus.
  N Engl J Med. 327(5):302-307.. 1992
  PUBMEDID: 1377788
• Persaud DR, Barranco-Mendoza A.
  Bovine serum albumin and insulin-dependent diabetes mellitus; is cow's milk still a possible toxicological causative agent of diabetes?
  Food Chem Toxicol. 42(5):707-714.. 2004
  PUBMEDID: 15046815
• Knip M.
  Cow's milk antibodies in patients with newly diagnosed type 1 diabetes: primary or secondary?
  Pediatr Diabetes. 4(4):155-156.. 2003
  PUBMEDID: 14710774
• Wang Y, Schubert M, Ingendoh A, Franzen J.
  Analysis of non-covalent protein complexes up to 290 kDa using electrospray ionization and ion trap mass spectrometry.
  Rapid Commun Mass Spectrom. 2000;14(1):12-17.. 2000
  PUBMEDID: 10623922
• Beretta B, Conti A, Fiocchi A, Gaiaschi A, Galli CL, Giuffrida MG, Ballabio C, Restani P.
  Antigenic determinants of bovine serum albumin.
  Int Arch Allergy Immunol. 126(3):188-195.. 2001
  PUBMEDID: 11752875
• Levi V, Gonzalez Flecha FL.
  Reversible fast-dimerization of bovine serum albumin detected by fluorescence resonance energy transfer.
  Biochim Biophys Acta 1599(1-2):141-148.. 2002
  PUBMEDID: 12479415
• Hunter AK, Carta G.
  Effects of bovine serum albumin heterogeneity on frontal analysis with anion-exchange media.
  J Chromatogr A. 937(1-2):13-19.. 2001
  PUBMEDID: 11765079
• Xu Y, Ding Z.
  A novel method for simultaneous purification of albumin and immunoglobulin G.
  Prep Biochem Biotechnol. 34(4):377-385.. 2004
  PUBMEDID: 15553906
• Mackensen A, Drager R, Schlesier M, Mertelsmann R, Lindemann A.
  Presence of IgE antibodies to bovine serum albumin in a patient developing anaphylaxis after vaccination with human peptide-pulsed dendritic cells.
  Cancer Immunol Immunother. 49(3):152-156.. 2000
  PUBMEDID: 10881694
• Havea P, Singh H, Creamer LK.
  Formation of new protein structures in heated mixtures of BSA and alpha-lactalbumin.
  J Agric Food Chem. 48(5):1548-1556.. 2000
  PUBMEDID: 10820057
• Werfel SJ, Cooke SK, Sampson HA.
  Clinical reactivity to beef in children allergic to cow's milk.
  J Allergy Clin Immunol. 99(3):293-300.. 1997
  PUBMEDID: 9058683
• Neyestani TR, Djalali M, Pezeshki M.
  Isolation of alpha-lactalbumin, beta-lactoglobulin, and bovine serum albumin from cow's milk using gel filtration and anion-exchange chromatography including evaluation of their antigenicity.
  Protein Expr Purif. 29(2):202-208. . 2003
  PUBMEDID: 12767810

Biochemical Information for Kappa-Casein

• Allergen Name:Kappa-Casein
• Alternatve Allergen Names:Bos d 8 (name for all caseins)
• Allergen Designation:
• Protein Family:Pfam PF00997; Kappa Casein family. This is distantly related to fibrinogen gamma-chain.
• Sequence Known?:Yes
• Allergen accession No.s:http://us.expasy.org/cgi-bin/niceprot.pl?P02668
• 3D Structure Accession No.:N/A
• Calculated Masses:

  21269 Da (precursor)
  19023 (mature)

• Experimental Masses:19 kDa.
• Oligomeric Masses:Caseins exist as micelles and large aggregates.
• Allergen epitopes:Chatchatee et al. (2001) [1197] used 80 overlapping synthetic decapeptides to identify residues 15-24, 37-46, 55-80, 83-92 and 105-116 as the regions binding to IgE from sera from 15 patients with persistent cow's milk allergy.
• Allergen stability:
  Process, chemical, enzymatic:Kappa-Casein is probably more structured than the alpha and beta caseins and contains specific disulphides (Rasmussen et al. 1992 [1419]; Rasmussen et al. 1994 [1418]). These can rearrange on heating (Creamer et al, 1998 [1422]). Kappa-casein is very sensitive to proteolysis. Allergenicity survives cooking.
• Nature of main cross-reacting proteins:IgE cross-reactivity is observed for caseins of buffalo, sheep and goat (Restani et al. 1999 [1624]).
• Allergen properties & biological function:Kappa-casein is critical to the stability of casein micelles (Creamer et al, 1998 [1422]). Bovine casein contains approximately 10% kappa-casein (Bernard et al, 1998 [1203]).
• Allergen purification:

  Caseins can be prepared from milk by precipitation at pH 4.6 with acetic acid, centrifuged (2250 x g for 5 minutes) and washed twice with 0.1 M ammonium acetate, pH 4.6 (Rasmussen & Petersen, 1991 [1416]). Individual caseins can then be separated by gel chromatography on a Sepharose CL-6B column or denatured and separated in urea (Rasmussen et al. 1994 [1418]).

  Strange et al. (1992) [1493] review the purification of proteins from milk.

• Other biochemical information:

  Natale et al. (2004) [1409] found that 50% of 20 sera from patients aged 4 months to 14 months contained IgE against kappa-casein.

  Kappa-caseins from sheep and goat are 87-88% identical in sequence making IgE cross-reactivity very likely. The kappa-casein sequence from horse is 45% identical suggesting that cross-reactivity is possible but likely to be rare. Human kappa-casein is less than 35% identical.

References (12)

• Chatchatee P, Jarvinen KM, Bardina L, Vila L, Beyer K, Sampson HA.
  Identification of IgE and IgG binding epitopes on beta- and kappa-casein in cow's milk allergic patients.
  Clin Exp Allergy. 31(8):1256-1262. . 2001
  PUBMEDID: 11529896
• Elsayed S, Hill DJ, Do TV.
  Evaluation of the allergenicity and antigenicity of bovine-milk alphas1-casein using extensively purified synthetic peptides.
  Scand J Immunol. 60(5):486-493.. 2004
  PUBMEDID: 15541041
• Lowe EK, Anema SG, Bienvenue A, Boland MJ, Creamer LK, Jimenez-Flores R.
  Heat-induced redistribution of disulfide bonds in milk proteins. 2. Disulfide bonding patterns between bovine beta-lactoglobulin and kappa-casein.
  J Agric Food Chem. 52(25):7669-7680. . 2004
  PUBMEDID: 15675819
• Strange ED, Malin EL, Van Hekken DL, Basch JJ.
  Chromatographic and electrophoretic methods used for analysis of milk proteins.
  J Chromatogr. 624(1-2):81-102.. 1992
  PUBMEDID: 1494022
• Rasmussen LK, Petersen TE.
  Purification of disulphide-linked alpha s2- and kappa-casein from bovine milk.
  J Dairy Res. 58(2):187-193.. 1991
  PUBMEDID: 1856353
• Rasmussen LK, Hojrup P, Petersen TE.
  Disulphide arrangement in bovine caseins: localization of intrachain disulphide bridges in monomers of kappa- and alpha s2-casein from bovine milk.
  J Dairy Res. 61(4):485-493.. 1994
  PUBMEDID: 7829753
• Bernard H, Creminon C, Yvon M, Wal JM.
  Specificity of the human IgE response to the different purified caseins in allergy to cow's milk proteins.
  Int Arch Allergy Immunol. 115(3):235-244.. 1998
  PUBMEDID: 9531166
• Natale M, Bisson C, Monti G, Peltran A, Garoffo LP, Valentini S, Fabris C, Bertino E, Coscia A, Conti A.
  Cow's milk allergens identification by two-dimensional immunoblotting and mass spectrometry.
  Mol Nutr Food Res. 48(5):363-369.. 2004
  PUBMEDID: 15672476
• Rasmussen LK, Hojrup P, Petersen TE.
  The multimeric structure and disulfide-bonding pattern of bovine kappa-casein.
  Eur J Biochem. 207(1):215-222.. 1992
  PUBMEDID: 1628650
• Syme CD, Blanch EW, Holt C, Jakes R, Goedert M, Hecht L, Barron LD.
  A Raman optical activity study of rheomorphism in caseins, synucleins and tau. New insight into the structure and behaviour of natively unfolded proteins.
  Eur J Biochem. 269(1):148-156.. 2002
  PUBMEDID: 11784308
• Restani P, Gaiaschi A, Plebani A, Beretta B, Cavagni G, Fiocchi A, Poiesi C, Velona T, Ugazio AG, Galli CL.
  Cross-reactivity between milk proteins from different animal species.
  Clin Exp Allergy. 29(7):997-1004.. 1999
  PUBMEDID: 10383602
• Creamer LK, Plowman JE, Liddell MJ, Smith MH, Hill JP.
  Micelle stability: kappa-casein structure and function.
  J Dairy Sci. 81(11):3004-3012.. 1998
  PUBMEDID: 9839241

Biochemical Information for Lactoferrin

• Allergen Name:Lactoferrin
• Alternatve Allergen Names:Lactotransferrin
• Allergen Designation:
• Protein Family:Pfam PF00405; Transferrin
• Sequence Known?:Yes
• Allergen accession No.s:http://us.expasy.org/uniprot/P24627
• 3D Structure Accession No.:1BLF
  1NKX (C-terminal domain)
  1SDX (C-terminal domain with added zinc)
• Calculated Masses:78056 Da (precursor)
• Experimental Masses:67 kDa
• Oligomeric Masses:Monomeric
• Allergen epitopes:Not known
• Allergen stability:
  Process, chemical, enzymatic:Lactoferrin shows two transitions by differential scanning calorimetry with the first peak at 65°C and the second peak at 92°C. These correspond to the denaturation of apo- and iron loaded lactoferrin (Paulsson et al. 1993 [1519]; Kulmyrzaev et al. 2005 [1520]).
• Nature of main cross-reacting proteins:

  Not known.

• Allergen properties & biological function:

  Lactoferrin is a glyco protein. If the carbohydrate moiety is cleaved, then iron binding activity is reduced. Lactoferrin has several antimicrobial roles (Vorland, 1999 [1515]) and expresssion is increased in response to infection (Zheng et al, 2005 [1516]). The main activity is the sequestration of iron. This may also protect cells from free radical damage by removing catalytic free iron. The antimicrobial peptide lactoferricin comprises residues 17 - 41 of mature lactoferrin or 36 - 60 of the precursor. This forms a disulphide linked hairpin in solution 1LFC. The peptide 265-284 also has antimicrobial activity (van der Kraan et al, 2005 [1517]).

• Allergen purification:

  Hahn et al. (1998) [1490] describe a partial purification of several whey proteins. Milk was delipidated by centrifugation and casein removed by adjusting to pH 4.7 and centrifugation. The whey was diluted to a conductivity of 2.7 mS/cm, the pH readjusted to 4.7 and then filtered through 0.45-µm membrane. The diluted whey was loaded onto one of 4 cation exchange columns (Macro-Prep High S Support, S-Sepharose Fast Flow, S-HyperD-F and Fractogel EMD SO₃^- 650 (S)) equilibrated with 20 mM citrate buffer at pH 4.7. Step elution with 0.1M, 0.3M and 1M NaCl from S-Sepharose Fast Flow gave lactoferrin with some lactoperoxidase contamination in the last step.

• Other biochemical information:

  Natale et al. (2004) [1409] found that 50% of 20 sera from cow's milk allergic patients aged 4 months to 14 months contained IgE against lactoferrin.

  Sheep and goat lactoferrins are 91% and 92% identical in sequence, suggesting that IgE cross-reactivity is almost certain. Horse lactoferrin is 72% identical suggesting that cross-reactivity is possible. Human lactoferrin is 69% identical but cross-reactivity may be prevented by clonal deletion. Mammalian serotransferrins are approximately 60% identical and no cross-reactivity has been reported.

References (7)

• Hahn R, Schulz PM, Schaupp C, Jungbauer A.
  Bovine whey fractionation based on cation-exchange chromatography.
  J Chromatogr A 795(2):277-287.. 1998
  PUBMEDID: 9528103
• Natale M, Bisson C, Monti G, Peltran A, Garoffo LP, Valentini S, Fabris C, Bertino E, Coscia A, Conti A.
  Cow's milk allergens identification by two-dimensional immunoblotting and mass spectrometry.
  Mol Nutr Food Res. 48(5):363-369.. 2004
  PUBMEDID: 15672476
• van der Kraan MI, van der Made C, Nazmi K, Van't Hof W, Groenink J, Veerman EC, Bolscher JG, Nieuw Amerongen AV.
  Effect of amino acid substitutions on the candidacidal activity of LFampin 265-284.
  Peptides. 2005 Jun 7; [Epub ahead of print]. 2005
  PUBMEDID: 15946771
• Vorland LH.
  Lactoferrin: a multifunctional glycoprotein.
  APMIS. 107(11):971-981.. 1999
  PUBMEDID: 10598868
• Zheng J, Ather JL, Sonstegard TS, Kerr DE.
  Characterization of the infection-responsive bovine lactoferrin promoter.
  Gene 353(1), 107-117. 2005
  PUBMEDID: 15935571
• Paulsson MA, Svensson U, Kishore AR, Naidu AS.
  Thermal behavior of bovine lactoferrin in water and its relation to bacterial interaction and antibacterial activity.
  J Dairy Sci. 76(12):3711-3720.. 1993
  PUBMEDID: 8132877
• Kulmyrzaev AA, Levieux D, Dufour E.
  Front-face fluorescence spectroscopy allows the characterization of mild heat treatments applied to milk. Relations with the denaturation of milk proteins.
  J Agric Food Chem. 53(3):502-507.. 2005
  PUBMEDID: 15686393