DETECTION OF ENDOGENOUS RETROVIRUS ANTIGENS IN NOD MOUSE PANCREATIC BETA-CELLS

We characterized C-type retroviruses expressed in the pancreatic p-cel ls of non-obese diabetic (NOD) mice by immunohistochemical techniques and by inhibiting the production of viral particles using antisense ol igonucleotides. Some cells in the pancreatic islets from both NOD and diabetes-resistant NOD-related mice (NON) reacted with a monoclonal an tibody directed against the envelope protein(s) of polytropic viruses. On the other hand, NOD islet cells also showed strong immunoreactivit y with an anti-gag protein monoclonal antibody and another anti-envelo pe protein(s) monoclonal antibody that is specific for xenotropic vise s. In antisense oligodeoxynucleotide inhibition assays, a xenotropic v irus-specific phosphorothionate antisense oligodeoxynucleotide signifi cantly inhibited the occurrence of C-type virus particles in NOD mouse islet beta-cells. Therefore, C-type retrovirus-like particles express ed in NOD mouse pancreatic beta-cells were considered to be endogenous xenotropic virus. The expression of the xenotropic viral genome may b e involved in the pathogenesis of the diabetic syndrome in NOD mice.