Monocyte Fc., Receptor Recognition of Cell-Bound and Aggregated tgG
نویسندگان
چکیده
Monocyte and macrophage Fc. receptors are important components in the recognition of IgG-coated cells and lgG-containing immune complexes. Two proteins have been identified on human peripheral blood monocytes that can function as Fc. receptors. Fc7Rl (70 Kd) and Fc. Rll (40 Kd). We studied the role of Fc.,RI and Fc.,RII on human monocytes by examining their binding of lgG-sensitized cells (human IgG anti-D-coated RBCs and rabbit IgGsensitized sheep RBCs) and their binding of human trimeric IgG. To examine the function of monocyte Fc RlI. we used an anti-Fc. RIl monoclonal antibody (MoAb) that competes for the Fc7RII ligand binding site. Preincubation of monocytes with saturating concentrations of anti-Fc. RlI MoAb did not alter the recognition of IgG (anti-D)-sensitized human RBCs by monocytes. Furthermore. ligand-binding
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