Aberrant T cell-mediated immunity in untreated schizophrenic patients: deficient interleukin-2 production.

The authors examined the immune status at the cellular and humoral levels of 16 untreated schizophrenic patients. No abnormality in the distribution of T cell subsets (CD4+, CD8+) was detected. The proliferative response to the T cell mitogen phytohemagglutinin was normal. No increase in the number of T cells showing activation markers, such as human leukocyte antigens and interleukin-2 receptors, was noted. Conversely, function studies revealed a clear deficiency in interleukin-2 production by purified T cells. This lower production was probably intrinsic to the patients' T cells, since interleukin-2 production showed normal sensitivity to prostaglandin E2-mediated down-regulation by autologous monocytes.