In vitro effects of retinoid RO 10-9359 on lectin-induced activation and proliferation of T-lymphocytes.

Abstract

RO 10-9359 has been shown to cause a dose-dependent (0.05-50 micrograms/ml) inhibition of proliferation of rat thymocytes after in vitro activation by PHA and Con A. In experiments designed to dissect the effects of the drug on various aspects of proliferation it was demonstrated that RO 10-9359 did not inhibit IL1 production by macrophages, nor the IL1-dependent events of T-cell activation, i.e. the IL2 production and the acquisition of IL2-receptors. However, the capacity of exogenously supplied IL2 to stimulate the proliferation of T-cells that had previously acquired IL2-receptors was suppressed by RO 10-9359 in a dose-dependent manner. Thus, it appears that retinoid RO 10-9359 does not interfere with the early events of T-cell activation, but inhibits lectin-induced proliferation by affecting the later phase of proliferative activity after T-cell triggering.