Cyclosporine does not inhibit the process of revascularization of pancreatic islet transplantation.

The immunosuppressive drug cyclosporin-A (CsA) has been widely used to prevent pancreatic islet allograft rejection. Because it has been suggested that CsA may inhibit the process of revascularization of transplanted islets, the purpose of the study was to analyze by a double indirect immunofluorescence technique the revascularization process of isolated islets grafted in the liver and in the renal subcapsular space of rats treated with immunosuppressive doses of CsA. Lewis rats were grafted with either Lewis (isografts) or Wistar (allografts) pancreatic islets obtained by collagenase digestion.

Immunocytochemical study of pancreatic islet revascularization in islet isograft. Effect of hyperglycemia of the recipient and of in vitro culture of islets.

We studied the revascularization process of isogeneic islets grafted into the kidney subcapsular space of streptozotocin-induced diabetic and nondiabetic rats by a double-labeling, indirect immunofluorescence technique using a rabbit antiserum to human factor VIII-related antigen (which identifies endothelial cells) and a guinea pig anti-insulin antiserum (which labels pancreatic beta cells). Freshly isolated islets contained a network of capillary endothelial cells, whereas 1-week-cultured islets at 37 degrees C have completely lost their intra-islet endothelial cells. Overnight cultured islets contained only occasional endothelial cells.