Inhibition and potentiation of T lymphocyte response to mitogens. Studies using two mitogenic stimuli simultaneously.
Rat thymocytes were stimulated with phytohaemagglutinin (PHA), Concanavalin A (Con A), pokeweed mitogen (PWM) and lipopolysaccharide (LPS) or with mixtures of two of these mitogens, added simultaneously to in vitro cultures. Four-five concentrations of first mitogen were matched with four-five concentrations of second mitogen, in all possible combinations. Synergistic effects were observed with LPS plus PHA and LPS plus PWM and inhibitory effects with PHA plus Con A and LPS plus Con A. The hypothesis is discussed that an inhibitory effects occurs when two mitogens react with identical or very similar receptors on the lymphocyte surface, while a synergistic effect is produced by two mitogens reacting with different receptors.
D000818:Animals; D002478:Cells, Cultured; D003208:Concanavalin A / Q000008:administration & dosage; D004347:Drug Interactions; D004926:Escherichia coli / Q000032:analysis; D005260:Female; D008070:Lipopolysaccharides / Q000008:administration & dosage; D008213:Lymphocyte Activation / Q000187:drug effects*; D008934:Mitogens / Q000008:administration & dosage*; D010835:Phytohemagglutinins / Q000008:administration & dosage; D011043:Pokeweed Mitogens / Q000008:administration & dosage; D051381:Rats; D011919:Rats, Inbred Strains; D013601:T-Lymphocytes / Q000187:drug effects*
D008070:Lipopolysaccharides; D008934:Mitogens; D010835:Phytohemagglutinins; D011043:Pokeweed Mitogens; D003208:Concanavalin A