[The effect of immunomodulating doses of purified staphylococcal anatoxin on the spontaneous and mitogen-induced proliferation of mouse splenocytes].

Purified staphylococcal toxoid (PST) was shown to alter the spontaneous and mitogen-induced proliferation of mouse spleen cells. In vitro, PST inhibited spontaneous proliferation, as well as proliferation induced by the optimal dose of Con A (2 micrograms/ml) and the optimal and suboptimal doses of lipopolysaccharide (LPS) (100 and 50 micrograms/ml). At the same time the dose of 1.5 binding units (BU) of PST, inhibiting spontaneous proliferation in vitro, induced strong proliferative response in combination with the suboptimal dose of Con A (1 microgram/ml). Our experiments demonstrated that the spontaneous proliferation of mouse spleen cells, immunized with the toxoid, remained unchanged (0, 15 or 15 BU/mouse) or increased (1.5 BU/mouse) the response of spleen cells of immune animals to ConA and LPS also changed in comparison with the control, depending on the conditions of the experiment. After the use of the combination of 2 micrograms of Con A and 1.5 BU of PST or 100 (50) micrograms of LPS and 1.5 BU of PST the inhibition of proliferative response was observed. The summation of the signals of the suboptimal dose of Con A (1 microgram) 1.5 BU of PST was demonstrated.