title: Interaction of human platelets with particle-adherent aggregated IgG: description of the experimental system and role of C1q and monomeric IgG.
abstract: We describe a system for studying the interaction of human, single donor platelets and aggregated human IgG adherent to erythrocyte stroma (ES/Agg IgG) and report the role of monomeric IgG and C1q in this interaction. Monomeric IgG inhibits platelet aggregation by the ES/Agg IgG and acts on the platelet surface. Complement components inhibit the aggregation of platelets by the ES/Agg IgG, and C1q is necessary but not sufficient for this inhibition. Complement components act on the ES/Agg IgG. The platelet Fc receptor does not consist solely of divalent cation-dependent complement components.
mesh_terms: D001792:Blood Platelets / Q000276:immunology*; D003166:Complement Activating Enzymes / Q000276:immunology*; D015922:Complement C1q; D004912:Erythrocytes / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D010974:Platelet Aggregation
chemical_list: D007074:Immunoglobulin G; D015922:Complement C1q; D003166:Complement Activating Enzymes