Variable effects of indomethacin and four related compounds on lymphocyte blastogenesis and cell-mediated cytotoxicity.

Activation of spleen cell cultures by T-cell mitogens appeared enhanced or suppressed by the presence of some nonsteroid anti-inflammatory drugs such as indomethacin and indomethacin esters in a dose-dependent fashion. However blastogenesis of B cells by bacterial lipopolysaccharide was inhibited by the same drugs at every concentration tested. In vivo treatment of mice with indomethacin led to an inhibition of both T and B lymphocyte responses to mitogens. Addition of indomethacin to Concanavalin A-stimulated spleen cells from indomethacin-treated mice further inhibited the response to the mitogen. Indomethacin and indomethacin esters induced only a slight inhibition of cell-mediated cytotoxic reactions when added to cultures, whereas these reactions were markedly inhibited in spleen cells from indomethacin-treated mice.