Islet cell surface antibodies in genetically obese hyperglycaemic (ob/ob) mice.
A quantitative method for circulating islet cell surface antibodies (ICSA), based on the binding of 125I-protein A to insulin-producing RINm5F cells, was used to evaluate ICSA in plasma of 4- to 40-week-old Aston obese hyperglycaemic (ob/ob) mice and normal control (+/+) mice. RINm5F cells bound 2502 +/- 1196 c.p.m. 125I-protein A per 10(5) cells (mean +/- S.D., n = 54) after incubation with +/+ plasma. ICSA positive plasma (defined as 125I-protein A binding, mean +/- 2 S.D. of +/+ plasma) was detected in 3 out of 54 +/+ mice and 3 out of 54 ob/ob mice. ICSA were not observed in ob/ob mice before the onset of diabetes (7 weeks of age), but were detected at 9, 20 and 40 weeks. At 20 weeks 125I-protein A binding produced by ob/ob plasma was 35% greater than +/+ plasma (P less than 0.05). The low occurrence of ICSA in ob/ob mice (6%) suggests that factors other than ICSA are responsible for B-cell dysfunction and eventual islet degeneration observed in Aston ob/ob mice.
D000375:Aging; D000818:Animals; D000954:Antigens, Surface / Q000276:immunology; D001323:Autoantibodies / Q000032:analysis*; D003921:Diabetes Mellitus, Experimental / Q000235:genetics / Q000276:immunology*; D006943:Hyperglycemia / Q000276:immunology; D007515:Islets of Langerhans / Q000276:immunology*; D051379:Mice; D008820:Mice, Obese / Q000276:immunology*
D000954:Antigens, Surface; D001323:Autoantibodies