title: Comparative resistance of food proteins to adult and infant in vitro digestion models.
abstract: IgE-mediated allergy to milk and egg is widespread in industrialised countries and mainly affects infants and young children. It may be connected to an incomplete digestion of dietary proteins causing an inappropriate immune response in the gut. In order to study this, a biochemical model of infant gastroduodenal digestion has been developed, which has reduced levels of protease (eightfold for pepsin and tenfold for trypsin and chymotrypsin), phosphatidylcholine and bile salts, compared with the adult model. This model has been used to study the behaviour of three characterised food-relevant proteins (bovine beta-lactoglobulin (beta-Lg), beta-casein (beta-CN) and hen's egg ovalbumin), all of which are relevant cows' milk and hens' egg allergens. Digestion products were characterised using electrophoresis, immunochemical techniques and MS. These showed that ovalbumin and beta-CN were digested more slowly using the infant model compared with the adult conditions. Resistant fragments of beta-CN were found in the infant model, which correspond to previously identified IgE epitopes. Surprisingly, beta-Lg was more extensively degraded in the infant model compared with the adult one. This difference was attributed to the tenfold reduction in phosphatidylcholine concentration in the infant model limiting the protective effect of this phospholipid on beta-Lg digestion.
authors: Institut National de la Recherche Agrononique-Agrocampus Ouest, UMR 1253 Science et Technologie du Lait et de l'oeuf, 65 rue de St. Brieuc, Rennes, France. didier.dupont@rennes.inra.fr
authors: Didier
authors: D
authors: Dupont
authors: Giuseppina
authors: G
authors: Mandalari
authors: Daniel
authors: D
authors: Molle
authors: Julien
authors: J
authors: Jardin
authors: Joëlle
authors: J
authors: Léonil
authors: Richard M
authors: RM
authors: Faulks
authors: Martin S J
authors: MS
authors: Wickham
authors: E N Clare
authors: EN
authors: Mills
authors: Alan R
authors: AR
authors: Mackie
mesh_terms: D000328:Adult; D000911:Antibodies, Monoclonal / Q000276:immunology; D002364:Caseins / Q000276:immunology / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D004063:Digestion; D006801:Humans; D007223:Infant; D007782:Lactoglobulins / Q000276:immunology / Q000378:metabolism*; D010047:Ovalbumin / Q000276:immunology / Q000378:metabolism*; D010713:Phosphatidylcholines / Q000032:analysis; D053719:Tandem Mass Spectrometry
chemical_list: D000911:Antibodies, Monoclonal; D002364:Caseins; D007782:Lactoglobulins; D010713:Phosphatidylcholines; D010047:Ovalbumin