title: Specificity of IgE antibodies from patients allergic to goat's milk and tolerant to cow's milk determined with plasmin-derived peptides of bovine and caprine β-caseins.
abstract: METHODS
  Despite a sequence homology of 90% between bovine and caprine β-caseins (CN), IgE antibodies from patients allergic to goat's milk (GM), but tolerant to cow's milk (CM), recognize caprine β-CN without cross-reacting with bovine β-CN. We investigated this lack of cross-reactivity by evaluating the IgE-reactivity toward peptides isolated from plasmin hydolysates of bovine and caprine β-CN.
  
  
  RESULTS
  The IgE-binding capacity of plasmin-derived peptides was evaluated with sera from 10 CM-allergic patients and 12 GM-allergic/CM-tolerant patients. In CM-allergic patients, IgE reactivity of caprine fragments (f29-107) and (f108-207), but not (f1-28), was similar to that of the bovine counterparts. In contrast, all bovine fragments were poorly recognized by IgE antibodies from GM-allergic/CM-tolerant patients. The peptide (f29-107) was generally the most immunoreactive fragment of caprine β-CN. By using synthetic peptides, the immunodominant IgE-binding epitope recognized by most GM-allergic/CM-tolerant patients was located in the caprine domain 49-79.
  
  
  CONCLUSIONS
  The restricted specificity of the IgE response toward the caprine β-CN in GM-allergic/CM-tolerant patients is mainly directed against the domain 49-79, which differs from its bovine counterpart by only three amino acid substitutions.
authors.affiliation: INRA, UR 496, Unité d'Immuno-Allergie Alimentaire, CEA de Saclay, Gif-sur-Yvette, France. herve.bernard-INRA@cea.fr
authors.forename: Hervé
authors.initials: H
authors.lastname: Bernard
authors.forename: Sandrine
authors.initials: S
authors.lastname: Ah-Leung
authors.forename: Sylvain
authors.initials: S
authors.lastname: Tilleul
authors.forename: Marie-Françoise
authors.initials: MF
authors.lastname: Drumare
authors.forename: Evelyne
authors.initials: E
authors.lastname: Paty
authors.forename: Etienne
authors.initials: E
authors.lastname: Bidat
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Wal
authors.forename: Stéphane
authors.initials: S
authors.lastname: Hazebrouck
mesh_terms: D000293:Adolescent; D000818:Animals; D002364:Caseins / Q000009:adverse effects / Q000276:immunology*; D002417:Cattle; D002648:Child; D002675:Child, Preschool; D003429:Cross Reactions; D005260:Female; D005341:Fibrinolysin / Q000378:metabolism*; D006041:Goats; D006801:Humans; D006868:Hydrolysis; D007073:Immunoglobulin E / Q000097:blood* / Q000276:immunology; D008297:Male; D008892:Milk / Q000737:chemistry*; D016269:Milk Hypersensitivity / Q000175:diagnosis / Q000276:immunology*
chemical_list: D002364:Caseins; D007073:Immunoglobulin E; D005341:Fibrinolysin