Infection by human cytomegalovirus and rubella virus of cultured human fetal islets of Langerhans.

Several viruses are implicated in the pathogenesis of pancreatic beta cell destruction and the onset of insulin-dependent (type 1) diabetes mellitus (IDDM). However, it is still controversial as to whether viral infection can exert direct cytopathic effects on beta cells. We have studied the effect of infection by human cytomegalovirus (CMV) and rubella virus on human fetal pancreatic islets in tissue culture. Although morphological changes were observed in CMV-inoculated islet cells, such infection did not lead to changes in levels of secreted immunoreactive insulin. On the other hand, infection by rubella virus did lead to significantly lower levels of immunoreactive insulin in the absence of demonstrable cytopathic effect. These results indicate that viral infection of human pancreatic islet tissue can occur as demonstrated through tissue culture techniques, and that such infection leads to changes in levels of secreted insulin in some cases but not others.