Immunomodulatory action of ampicillin.

Ampicillin was found to have an immunoenhancing effect on the expression of FcM human lymphocyte receptors, on the angiogenic potential of human lymphocytes and on the production of anti-SRBC antibody after in vivo administration to low-responder strains of mice. The effect of ampicillin on the graft-versus-host disease in irradiated F1 recipients of spleen cells from presensitized donors was found to be stimulatory when the drug was given to the recipients and suppressive when the drug was administered to the donors which had been preimmunized with a lower dose of antigen.