Cytophilic binding of IgE to the macrophage: II. Immunologic release of lysosomal enzyme from macrophages by IgE and anti-IgE in the rat: A new mechanism of macrophage activation

摘要: Abstract Rat peritoneal macrophages release lysosome granule-associated β-glucuronidase, but not cytoplasmic leucine aminopeptidase, after successive incubation with purified IgE protein and ϵ-specific anti-IgE antibody or F(ab′) 2 fragments. The selective of β-glucuronidase was shown to proceed by a first step binding the cell surface, followed IgE-anti-IgE reaction on macrophage, whereas possibility activation complexes in bulk phase ruled out. Heating rat destroyed its ability mediate lysosomal enzyme release. characteristics macrophage activation, insofar as is concerned, were agreement those reported for fixation mononuclear phagocyte, optimal being achieved 20 min incubation. Preincubation IgG, either aggregated aggregated, did inhibit addition antibody. Simultaneous monolayers IgG reduce subsequent anti-IgE. These studies indicated that can bind through specific receptor, no interference classical Fc (γ) are triggered enzymes upon conformational changes molecule Antibody-dependent cytotoxicity schistosomiasis mediated parasite, which may therefore function activating an efficient effector cell.