Analysis of IL-2 receptor positive CD8(+)-T-lymphocytes grown from islets of NOD mice.

IL-2 receptor positive T-cells from leukocyte-infiltrated pancreatic islets of diabetes prone or acutely diabetic NOD mice were propagated in vitro by culture in interleukin-2 containing medium. Of 13 lines obtained after limiting dilution all were positive for the T-cell marker Thy-1 and for CD8. Considerable heterogeneity in T-cell receptor usage was noted. Seven lines expressed T-cell receptors using V beta 8, one line was positive for V beta 5 and two lines expressed a non V beta 5, non V beta 8 receptor. Finally, two further lines lacked T-cell receptors. None of the cell lines were cytotoxic to islet cells although 10 lines showed non MHC restricted lysis of one or more tumour cells including rat insulinoma cells. We conclude that IL-2 receptor positive CD8+ T-lymphocytes from NOD islets are heterogenous with respect to V beta T-cell receptor usage. The majority of these cells are not cytotoxic to islet cells.