Suppressor cells in vitro: differential effects of indomethacin and related compounds.

In vitro immune response systems known to involve suppressor cell regulation were examined for effects produced by the drug indomethacin and other compounds known to inhibit the cyclooxygenase pathway of arachidonic acid metabolism. In all cases tested where suppressor T cell activity is known to be the dominant inhibitory mechanism, suppression was not blocked by drug addition and was sometimes more pronounced. In the cases tested where suppression could be attributed to a non-T cell, most likely a macrophage-like cell (M0), suppression could be abolished by drug treatment. Indomethacin and related compounds may be useful analytical tools for separation of T cell vs. non-T cell mediated suppression.