title: Suppressor macrophages in lymphocyte proliferation of cynomolgus monkeys.
abstract: The present study demonstrated the presence of cells belonging to monocyte/macrophage lineage which suppressed mitogen-induced blastogenesis of peripheral blood lymphocytes in cynomolgus monkeys. Depletion of adherent or phagocytic cells from peripheral mononuclear cells caused a substantial increase in the blastogenic response of cynomolgus monkey lymphocytes whereas the same treatment led to marked reduction rather than enhancement in human lymphocyte blastogenesis. Addition of thioglycollate-elicited peritoneal exudate adherent cells as macrophages suppressed the blastogenic response of nonadherent lymphocytes in a dose-dependent manner. The suppressive effect was observed not only in autologous but also in allogeneic macrophages to the responder lymphocytes. Treatment of macrophages with silica, carrageenan or freezing-thawing reduced their suppressive effect but there was no reduction with mitomycin C or indomethacin. No suppressive activity was detected in the cell-free supernatant of macrophages cultured in the presence or absence of mitogens for up to 4 days. From these findings, it appeared that monocyte/macrophage lineage might be responsible for the observed suppressive effect on mitogen-induced blastogenesis of cynomolgus monkey lymphocytes.
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002450:Cell Communication; D005260:Female; D007108:Immune Tolerance; D066298:In Vitro Techniques; D008213:Lymphocyte Activation; D008251:Macaca / Q000276:immunology*; D008252:Macaca fascicularis / Q000276:immunology*; D008264:Macrophages / Q000276:immunology*; D008297:Male; D008934:Mitogens / Q000494:pharmacology; D009000:Monocytes / Q000276:immunology; D010586:Phagocytes / Q000276:immunology
chemical_list: D008934:Mitogens