Effect of chloramphenicol on in vitro function of lymphocytes.

The effect of chloramphenicol on the in vitro function of human peripheral blood lymphocytes was studied in assays of lymphocyte transformation and lymphokine production. When lymphocytes were stimulated by phytohemagglutinin, concanavalin A, or pokeweed mitogen in the presence of various concentrations of chloramphenicol, only minimal effects on blastogenesis were noted. However, suppression by chloramphenicol of blastogenesis induced by candida antigen or streptokinase-streptodornase was greater in magnitude and was dose-dependent; blastogenesis was suppressed to 25%--30% or normal levels by concentrations of chloramphenicol of 25--50 microgram/ml. Chloramphenicol had little effect on the production of the lymphokine leukocyte migration inhibition factor by lymphocytes stimulated either by candida antigen or by concanavalin A, whereas puromycin at a concentration of 5 microgram/ml significantly suppressed this response. Thus chloramphenicol appears to suppress antigen-induced lymphocyte blastogenesis significantly but not lymphokine production by stimulated lymphocytes.