Effect of iC3b binding to immune complexes upon the phagocytic response of human neutrophils: synergistic functions between Fc gamma R and CR3.
We compared the phagocytosis of immune complexes (IC) and iC3b-opsonized derivatives (iC3b-IC) by human neutrophils. The phagocytosis of iC3b-IC via Fc gamma R and CR3 was much greater than that of IC via Fc gamma R alone. Adding ethanol to the cells decreased iC3b-IC phagocytosis to that of IC, which was not affected by these reagents, suggesting that the enhanced phagocytosis is attributable to CR3-mediated phospholipase D activation. The IC phagocytosis was inhibited more effectively by anti-Fc gamma IIIB, whereas the iC3b-IC phagocytosis was partly inhibited only by anti-Fc gamma RII. The main Fc gamma R might differ in IC and iC3b-IC phagocytosis.
Ohkuro
M
M
Department of Hygienic Chemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan.
Ogura-Masaki
M
M
Kobayashi
K
K
Sakai
M
M
Takahashi
K
K
Nagasawa
S
S
D000936:Antigen-Antibody Complex / Q000276:immunology / Q000378:metabolism*; D003179:Complement C3b / Q000276:immunology / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D000431:Ethanol / Q000494:pharmacology; D006801:Humans; D016177:Macrophage-1 Antigen / Q000276:immunology*; D009504:Neutrophils / Q000276:immunology*; D009895:Opsonin Proteins / Q000276:immunology; D010587:Phagocytosis / Q000187:drug effects; D010739:Phospholipase D / Q000378:metabolism; D011433:Propranolol / Q000494:pharmacology; D017452:Receptors, IgG / Q000276:immunology*
D000936:Antigen-Antibody Complex; D016177:Macrophage-1 Antigen; D009895:Opsonin Proteins; D017452:Receptors, IgG; D000431:Ethanol; D003179:Complement C3b; D011433:Propranolol; D010739:Phospholipase D