Islet cell autoantibodies and insulin-dependent (type I) diabetes mellitus

The presence of circulating islet cell autoantibodies (ICA) in a large majority of patients with newly diagnosed insulin-dependent (type I) diabetes mellitus (IDDM) suggests that autoimmune mechanisms may be associated with the loss of B cells in IDDM. Such ICA represent a heterogeneous group of antibodies which react with different cells within the islets as well as various cytoplasmic and membrane epitopes on single islet cells. These ICA are even detected prior to the development of overt diabetes, suggesting that the destruction of B cells may occur long before diabetes becomes clinically manifest. Immunotherapy, directed towards modifying this destructive process, has recently been attempted in humans, with the aim of retarding or even preventing the development of diabetes. Preliminary data have not shown any clear benefit from such intervention. However, in the spontaneously diabetic Bio-Breeding (BB) Wistar rat, a widely-studied animal model for IDDM, favourable response to immunotherapy has been reported.