Modifying and/or regulating effects on Fcμ receptor (R) mediated phagocytic and ADCC activity of both resident (r) and provoked (p) peritoneal macrophages (PM) was studied applying drugs affecting the cytoskeleton and cation transport. In addition, the effects of exogenous PGE2 and cyclic nucleotides were also examined. Fcμ-receptors appear to be functionally less significant in provoked PMs than in resident ones since both Fcμ-receptor mediated phagocytosis and ADCC were lower in the formers. The cytoskeletal system is important in the regulation of both Fcμ-receptor-mediated functions. Phagocytosis through Fcμ-receptor is decreased by Cytochalasin B and by Vinblastine treatment, whereas ADCC is enhanced by Cytochalasin B. Extracellular PGE2 and cAMP induced a higher phagocytic activity and suppressed ADCC, whereas cGMP displayed an opposite effect. The sensitivity of FcμR-mediated activities to ionophoric and to cytoskeleton-damaging drugs was lower in provoked than in resident PMs. In addition, the regulatory role of PGE2 and of cyclic nucleotides on the same activities was less marked on provoked PMs. In contrast, ouabain inhibits FcμR-dependent antigen incorporation and ADCC on provoked PM monolayers only. These findings suggest differing regulatory mechanisms for FcμR-mediated functions in provoked PMs as compared with resident ones.
ASJC Scopus subject areas
- Immunology and Allergy