[Inhibitory effect of serum on the phagocytic activity of macrophages in vitro]

The effect of blood sera obtained from sick and healthy persons on the phagocytic activity of mouse macrophages has been studied by means of in vitro tests. The study was made on blood serum samples taken from patients with diseases owing their pathogenesis largely to the role of macrophages, such as hemoblastosis (acute leukosis, myeloleukemia, erythremia), cancer of the larynx, parasitic diseases (acute and chronic opisthorchiasis, schistosomiasis). These patients were found to have humoral factors suppressing the phagocytic activity of mouse macrophages in vitro accumulated in their blood. The test allowing to evaluate the level of humoral antimacrophage suppressants has been developed. The formation of these mediators is supposed to occur in the spleen, as the suppressant action of blood serum disappears after splenectomy.