THALIDOMIDE AND ITS METABOLITES HAVE NO EFFECT ON HUMAN LYMPHOCYTE-PROLIFERATION

Thalidomide is a drug that is being used in several diseases with an i mmunological component, but the effects on the different immune functi ons have only been studied partially. Therefore, we studied the effect of thalidomide on PPD- or Con-A-induced proliferation of human mononu clear cells. We found no direct effect of thalidomide at up to 50 mu g /ml on the cultures. Cells taken from subjects 6 h after ingestion of 200 mg of thalidomide proliferated equally well to PPD and Con-A than cells taken prior to drug administration. Plasma taken from subjects t hat ingested 200 mg of thalidomide 6 h before did not affect the proli ferative response of their own cells when added to the culutures. Plas ma from rabbits that were injected with doses 5 or 15 times higher tha n the dose given to humans did not diminish the proliferative response of human mononuclear cells to PPD. We conclude that neither thalidomi de nor its metabolites affect the proliferative response of human mono nuclear cells.