EXPOSURE TO SUPERANTIGENS AS AN IMMUNOGENETIC EXPLANATION OF TYPE-I DIABETES MINI-EPIDEMICS

Insulin-dependent diabetes mellitus (IDDM) is considered to be an auto immune disease. Autoimmune diseases result from the breakdown of self- tolerance elicited by environmental factors on a susceptible genetic b ackground. This reduced tolerance allows competent cells to attack nor mal present on an individual's tissues. The study of the T cells prese nt in the islets of patients who died at the onset of the disease allo wed the recognition of ''superantigens'' as etiopathogenetic factors i n the development of IDDM. Since superantigens are the product of bact eria or viruses able to quickly stimulate a large number of the periph eral T cells sharing the same T cell receptor V beta segments once pre sented by certain HLA class II molecules, a number of observations in genetics, immunology, virology and epidemiology can now find a unifyin g explanation.