[Mitogenic activity of Staphylococcus aureus metabolites in cultures of whole and T- and B-fractionated human lymphocytes].

The stimulating action of the mitogenically active S. aureus metabolite (MASAM), described in earlier works, in the cultures of human peripheral blood lymphocytes, both nonfractionated and separated into T- and B-fractions, as well as the effect of macrophage removal on the sensitivity of lymphocytes to MASAM, were studied. MASAM was found to stimulate T- and B-lymphocyte cultures. The removal of phagocytic cells by means of carbonyl iron resulted in the enhanced sensitivity of nonfractionated lymphocyte cultures to MASAM, inhibited the response of T-lymphocytes to MASAM and had no effect on the sensitivity of B-lymphocyte cultures to the mitogen under study. The comparison of the effect produced on lymphocyte cultures by MASAM and by the commonly used mitogen, phytohemagglutinin, demonstrated that after the removal of macrophages T-lymphocyte cultures lost their sensitivity to MASAM to a greater degree than their sensitivity to phytohemagglutinin. The possible causes of these effects are discussed.