Ionophore A23-187 induces responses to TCGF in mouse lymphocytes

The process of activation of T lymphocytes by ionophoric substances was analysed according to current concepts of T-lymphocyte activation. Proliferation induced by the ionophore A23-187 was found to be strictly dependent on the exogenous availability of growth factors. Lack of production of growth factors in spleen cell cultures containing the ionophore A23-187 explained the failure to directly stimulate mouse T-lymphocyte proliferation. It was concluded that the main action of A23-187 is the induction of expression of growth receptors, and that the increase in Ca++ uptake is, in itself, not sufficient to induce mitotic events.