[Effect of the secretion products of mononuclear phagocytes on the proliferative activity of connective tissue cells].

3H-thymidine uptake was used to study the effect of the media conditioned by murine peritoneal macrophages and human peripheral blood monocytes on proliferative activity of 3T3 fibroblasts, smooth muscles of the umbilical vein and bone marrow fibroblasts. Secretory products of murine macrophages and human blood monocytes inhibited the proliferation of all 3 types of target cells. Latex phagocytosis by macrophages led to the increase in the inhibitory activity of the media conditioned by macrophages, whereas upon latex phagocytosis by monocytes the inhibitory action of the conditioned media was unchanged. Addition of rodexman to monocyte cultures did not produce any effect on the inhibitory action of the conditioned media. Activation of monocytes by lipopolysaccharide resulted in the diminution of the inhibitory action of the monocyte-conditioned media only with respect to smooth muscle cells. Lipopolysaccharide did not affect the action of the media conditioned with macrophages.