title: HLA-DQ8 transgenic and NOD mice recognize different epitopes within the cytoplasmic region of the tyrosine phosphatase-like molecule, IA-2.
abstract: Type 1 diabetes mellitus is strongly associated with HLA-DQ8 in humans and I-A(g7) in the NOD mouse. The disease is characterized by loss of tolerance to auto-antigens such as GAD, insulin, and the protein tyrosine phosphatase-like molecule, IA-2. We identified T cell epitopes on the intracytoplasmic region of IA-2 by immunizing DQ8/NOD, DQ8/B10, and NOD mice with overlapping 18 mer peptides in CFA. We identified four peptides presented both by DQ8 and NOD, five DQ8 specific peptides, and six NOD specific peptides. Both mouse lines failed to respond to ten peptides. We demonstrated MHC class II and CD4 restriction of proliferative responses using appropriate blocking antibodies. To understand the role of non-MHC genes in the generation of immune response to the islet auto-antigen, we evaluated cytokine secretion following immunization of DQ8 transgenic mice with strongly immunogenic peptides. The NOD background resulted in increased secretion of cytokines. In conclusion, we have identified IA-2 peptides that induce lymphoproliferative responses in DQ8 transgenic and NOD mice and shown that these peptides stimulate production of Th1 and Th2 cytokines.
authors.affiliation: Division of Endocrinology, Metabolism and Nutrition, Mayo Clinic, Rochester, Minnesota 55905, USA.
authors.forename: Y C
authors.initials: YC
authors.lastname: Kudva
authors.forename: Y J
authors.initials: YJ
authors.lastname: Deng
authors.forename: R
authors.initials: R
authors.lastname: Govindarajan
authors.forename: R S
authors.initials: RS
authors.lastname: Abraham
authors.forename: E V
authors.initials: EV
authors.lastname: Marietta
authors.forename: A L
authors.initials: AL
authors.lastname: Notkins
authors.forename: C S
authors.initials: CS
authors.lastname: David
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019138:Antibodies, Blocking / Q000494:pharmacology; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D001324:Autoantigens; D016207:Cytokines / Q000032:analysis / Q000378:metabolism; D003593:Cytoplasm / Q000201:enzymology / Q000276:immunology* / Q000378:metabolism*; D018984:Epitopes, T-Lymphocyte / Q000032:analysis / Q000378:metabolism*; D006683:HLA-DQ Antigens / Q000235:genetics* / Q000276:immunology; D006801:Humans; D008213:Lymphocyte Activation / Q000235:genetics; D008565:Membrane Proteins / Q000276:immunology* / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D016688:Mice, Inbred NOD; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000276:immunology / Q000378:metabolism; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1; D017027:Protein Tyrosine Phosphatases / Q000276:immunology* / Q000378:metabolism*; D054635:Receptor-Like Protein Tyrosine Phosphatases, Class 8; D018417:Th1 Cells / Q000276:immunology / Q000378:metabolism; D018418:Th2 Cells / Q000276:immunology / Q000378:metabolism; D019076:Transgenes / Q000276:immunology*
chemical_list: D019138:Antibodies, Blocking; D000911:Antibodies, Monoclonal; D001324:Autoantigens; D016207:Cytokines; D018984:Epitopes, T-Lymphocyte; D006683:HLA-DQ Antigens; C109756:HLA-DQ8 antigen; D008565:Membrane Proteins; D010446:Peptide Fragments; C516862:PTPRN protein, human; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1; D017027:Protein Tyrosine Phosphatases; C516863:Ptprn protein, mouse; D054635:Receptor-Like Protein Tyrosine Phosphatases, Class 8