Anti-pancreatic immunity in genetically diabetic mice.

The anti-pancreatic immune reaction of genetically diabetic homozygote C57Bl/KsJ db/db mice was studied with an in vitro test using murine islet of Langerhans cells as target cells. C57Bl/KsJ db/db spleen lymphocytes inhibited insulin secretion by the islet cells. This inhibition was abolished when T cells were eliminated by treatment with anti-Thy 1.2 monoclonal antibody in the presence of complement. Together with this cell-mediated cytotoxicity, complement-dependent antibody (CDA) and antibody-dependent cell cytotoxicity (ADCC) were found in the sera of these mice. A longitudinal study showed that this anti-pancreatic toxicity was detectable as early as the 10th day of life and lasted throughout the entire life span of the animal. None of these anomalies was found in control heterozygote mice.