title: T cells from children with IDDM are sensitized to bovine serum albumin.
abstract: Epidemiological and experimental evidence suggested that denial of dietary cow milk protein early in life protects genetically susceptible children and animals from insulin-dependent diabetes (IDDM). Bovine serum albumin (BSA) was proposed as a candidate milk-borne mimicry antigen responsible for the diabetogenic cow milk effect. Elevated anti-BSA antibodies have been observed in patients and diabetic rodents, and these antibodies precipitate p69 from islet cell lysates. IDDM is a T cell mediated disorder but efforts to detect BSA-specific T cells in diabetic children have so far failed. We describe here a culture system which allowed the detection of BSA-specific T cells and we mapped this response to the ABBOS peptide (pre-BSA position 152-169) previously identified as a possible mimicry epitope. ABBOS-sensitized T cells were found in 28/31 children with recent onset IDDM but not in non-diabetic controls nor in children with SLE or JRA. T cell proliferative responses declined within the first few years of diabetes diagnosis. Although no effector cell role for BSA/ABBOS specific T lymphocytes has been demonstrated, the presence of BSA peptide-specific T cells strengthens the postulated link between a cow milk protein and IDDM.
authors.affiliation: Department of Pediatrics, University of Toronto, Hospital For Sick Children, Ontario, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Cheung
authors.forename: J
authors.initials: J
authors.lastname: Karjalainen
authors.forename: J
authors.initials: J
authors.lastname: Vandermeulen
authors.forename: D P
authors.initials: DP
authors.lastname: Singal
authors.forename: H M
authors.initials: HM
authors.lastname: Dosch
mesh_terms: D000293:Adolescent; D000595:Amino Acid Sequence; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000276:immunology*; D005260:Female; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000276:immunology; D012710:Serum Albumin, Bovine / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D010446:Peptide Fragments; D012710:Serum Albumin, Bovine