title: Human neutrophil aggregation and increased adherence to human endothelial cells induced by heat-aggregated IgG and immune complexes.
abstract: Several types of IgG-dependent phagocytic stimuli independent of complement were investigated for their property to induce human polymorphonuclear neutrophil leucocyte (PMN) aggregation and adherence to human endothelial cells (EC) in culture. A Coulter counter method was employed for the detection of cell aggregation. Aggregated IgG, ovalbumin-anti-ovalbumin (OV anti-OV) immune complexes (both insoluble and soluble) and opsonized latex particles induced a significant degree of PMN aggregation which was detectable as early as 2 min after exposure of PMN to these stimuli. This aggregation was dependent on divalent cations (Ca++, Mg++). The same phagocytic stimuli furthermore significantly increased adherence of PMN to cultured human EC and serum-coated plastic. Controls consisting of native IgG, and OV anti-OV complexes prepared from Fab')2 antibody failed to induce either aggregation or increased adherence of PMN. These data suggest that exposure of PMN to IgG-dependent phagocytic stimuli induces increased adhesiveness of PMN and that interaction between the Fc-receptor of PMN and the Fc-portion of phagocytic stimuli is essential for this effect.
mesh_terms: D000936:Antigen-Antibody Complex / Q000276:immunology*; D002413:Cations, Divalent / Q000494:pharmacology; D002448:Cell Adhesion; D002449:Cell Aggregation / Q000187:drug effects; D002478:Cells, Cultured; D004727:Endothelium / Q000166:cytology; D006358:Hot Temperature; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D007841:Latex Fixation Tests; D009504:Neutrophils / Q000276:immunology / Q000502:physiology*; D010587:Phagocytosis
chemical_list: D000936:Antigen-Antibody Complex; D002413:Cations, Divalent; D007074:Immunoglobulin G