Expression of class II MHC antigens in murine pancreas after streptozocin-induced insulitis.

In this study, most class II antigen expression during streptozocin-induced insulitis was associated with the mononuclear cells infiltrating the pancreas. During the early stages of the insulitis response, phagocytic cells expressing class II antigens and containing beta-cell debris were often observed. Although there was de novo expression of class II antigens by ductular epithelium associated with the exocrine portion of the pancreas and transient expression by vascular endothelial cells, the endocrine cells of the islets remained devoid of class II antigens throughout the period of observation (42 days).

Expression of Ia antigens by murine kidney epithelium after exposure to streptozotocin.

In the normal murine kidney, Ia antigens are expressed by dendritic cells located within the interstitial connective tissue and scattered cells within the glomerulus. After receiving multiple low doses of streptozotocin, a nitrosourea derivative of glucose, kidney epithelium labeled intensely with anti-Ia antibodies. Ultrastructural immunohistochemistry indicated that the epithelial cells of the proximal convoluted tubules expressed Ia antigens on their basolateral surfaces while remaining Ia- on their luminal surfaces. This response to streptozotocin does not appear to be related to the diabetogenic potential of the drug, because BALB/cJ mice, which remain normoglycemic after treatment with streptozotocin, also exhibited strongly Ia+ tubular epithelium after treatment with streptozotocin.