The immunosuppressive effects of verapamil upon mitogen activated and allo-antigen inducible human cytotoxic T-lymphocytes.

In this study, the effect of verapamil, a phenylalkylamine-type Ca2+ antagonist, upon the activation of human mononuclear cells was investigated and a detailed analysis of the kinetics and dose related effects of verapamil upon alloreactive cytotoxic T-cells (CTL) was undertaken. Verapamil suppressed the release of interleukin-2, proliferation and generation of CTL activity in mitogen and alloantigen stimulated human T-lymphocytes in a dose related fashion. Verapamil suppressed the steady state levels of several T-cell activation-associated gene transcripts, i.e. the mRNA encoding for interleukin-2, and a cytotoxic T-cell specific serine esterase. Verapamil exerted a novel immune-suppressive effect, i.e. the inhibition of mature alloantigen-inducible cytolytic T-cells, thus rendering verapamil a progenitor of potent and clinically useful immunosuppressive drugs.