The effect of phorbol-myristate acetate and concanavalin A on the growth of interleukin-2-dependent T-cell lines.

We tested the effect of phorbol myristate acetate (PMA) and of Con A on the growth of two Il-2 dependent T cell-lines. Il-2 dependent growth, as measured by 3H-TDR incorporation or viable cell counts was enhanced by PMA (5-100 ng/ml) and inhibited by Con A. These effects were only reproducible in the presence of intermediate concentrations of Il-2 containing supernatant. The enhancing effect of PMA was probably due to a positive influence on the replication rate since the drug had no visible effect on cell survival and since no evidence was found for the induction of Il-2 production by the cell-lines.