Cimetidine does not stimulate human T lymphocyte functions in vitro.

Cimetidine, an H2-receptor antagonist had no immunoproliferative or immunostimulative effect on in vitro T cell functions of normal human peripheral blood lymphocytes. This was shown by adding Cimetidine to mitogen, alloantigen and xenoantigen-stimulated cultures. Generation of helper and cytotoxic T cells was not modified in a full kinetic experiment. These data failed to confirm previous reports showing an increase of cell-mediated immunity under Cimetidine therapy.