Morphologic-histochemical characterization of inflammatory cells in insulitis induced by multiple subdiabetogenic doses of streptozotocin in C57B1/KsJ mice.

Insulitis can be induced in C57B1/KsJ mice by injection of subdiabetogenic doses of streptozotocin (SZ, 40 mg/kg body weight) on five consecutive days. Subsequent to the resulting insulitis, a persisting diabetes syndrome develops. This experimental diabetes is regarded as a model of insulin-dependent diabetes mellitus in man (IDDM, type I). Insulitis is considered as a cellular immune reaction against the beta cells in the islets of Langerhans. This paper describes an ultrastructural study showing that lymphoid cells destroy the outer membranes of beta cells. No histochemical indications of the presence of T lymphocytes were found. Some of the lymphocytes are characterized as natural killer cells (NK cells) according to their histochemical and ultrastructural features.