title: T-cell epitope-containing hypoallergenic β-lactoglobulin for oral immunotherapy in milk allergy.
abstract: Optimally hydrolyzed β-Lactoglobulin (βLg) is a promising milk oral immunotherapy (OIT) candidate with respect to showing reduced B-cell reactivity but retaining the T-cell epitope. To demonstrate that an edible hypoallergenic βLg hydrolysate containing the T-cell epitope is suitable for OIT. We tested how chymotrypsin affected the retention of the T-cell epitope of βLg when preparing βLg hydrolysates using food-grade trypsin.
  
  
  
  We investigated the effect of chymotrypsin activity on the formation of the T-cell epitope-containing peptide of βLg (βLg102-124) and prepared an edible βLg hydrolysate containing βLg102-124using screened food-grade trypsins. B-cell reactivity was determined using immunoassays in which ELISA was performed with anti-βLg rabbit IgG and Western blotting was performed with a milk-specific IgE antiserum.
  
  
  
  In βLg hydrolysis performed by varying the activity of trypsin and chymotrypsin, chymotrypsin activity inhibited the formation of βLg102-124with an increase in hydrolysis time in a dose-dependent manner. βLg102-124was generated by two of five food-grade trypsins used at a ratio of 1:50 (w/w, enzyme/substrate) for 20 h at 40°C. The edible βLg hydrolysate retained βLg102-124and showed a reduction in molecular weight distribution and antigenicity against IgG and IgE.
  
  
  
  Chymotrypsin activity inhibited the formation of βLg102-124in the trypsin hydrolysate of βLg. This βLg trypsin hydrolysate is a novel candidate for peptide-based OIT in cow's milk allergy for safely inducing desensitization.
authors.affiliation: Research and Development Department, Bean Stalk Snow Co., Ltd., Kawagoe, Japan.
authors.forename: Hiroshi M
authors.initials: HM
authors.lastname: Ueno
authors.affiliation: Research and Development Department, Bean Stalk Snow Co., Ltd., Kawagoe, Japan.
authors.forename: Teruhiko
authors.initials: T
authors.lastname: Kato
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Ohnishi
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Kawamoto
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu, Japan.
authors.forename: Zenichiro
authors.initials: Z
authors.lastname: Kato
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Kaneko
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu, Japan.
authors.forename: Naomi
authors.initials: N
authors.lastname: Kondo
authors.affiliation: Research and Development Department, Bean Stalk Snow Co., Ltd., Kawagoe, Japan.
authors.forename: Taku
authors.initials: T
authors.lastname: Nakano
mesh_terms: D000485:Allergens / Q000276:immunology / Q000378:metabolism*; D000818:Animals; D002918:Chymotrypsin / Q000378:metabolism; D003888:Desensitization, Immunologic / Q000379:methods*; D018984:Epitopes, T-Lymphocyte / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D007073:Immunoglobulin E / Q000378:metabolism; D007223:Infant; D007782:Lactoglobulins / Q000276:immunology / Q000378:metabolism*; D008297:Male; D008892:Milk / Q000276:immunology; D016269:Milk Hypersensitivity / Q000276:immunology / Q000628:therapy*; D010455:Peptides / Q000276:immunology / Q000378:metabolism*; D011492:Protein Hydrolysates / Q000627:therapeutic use*; D059748:Proteolysis
chemical_list: D000485:Allergens; D018984:Epitopes, T-Lymphocyte; D007782:Lactoglobulins; D010455:Peptides; D011492:Protein Hydrolysates; D007073:Immunoglobulin E; D002918:Chymotrypsin
keywords: antigenicity; chymotrypsin; epitope; food allergy; hydrolysis; milk; oral immunotherapy; trypsin; β-lactoglobulin