Anti platelet property of anti-single-stranded DNA antibodies in type 1 (insulin-dependent) diabetes mellitus.

Nineteen of 50 sera from children with type 1 (insulin-dependent) diabetes mellitus showed anti-platelet reactivity. This reactivity was significantly associated with the presence of proteoglycan cross-reactive anti-ssDNA antibodies. As well as DNA-anti-DNA interaction, increasing salt concentration of the dilution buffer caused a decrease in the binding of positive sera to platelets. Purified ssDNA inhibited also the anti-platelet reactivity of anti-ssDNA positive sera. The addition of purified IgG from anti-ssDNA positive but not from anti-ssDNA negative sera to washed platelets caused an increased collagen-induced platelet aggregation similar to that obtained with the addition of polycationic agents. It may be suggested that ionic interaction between anti-negative charged molecule antibodies (such as anti-ssDNA antibodies) and platelet surface negative charges may be a pathophysiological mechanism contributing to the altered platelet function observed in diabetes.