title: The measurement of platelet-associated IgG by a microplate quantitative antiglobulin consumption assay using automated through-the-well spectrophotometry.
abstract: A microplate modification of the quantitative antiglobulin consumption assay (QACA) has been developed for the measurement of platelet-associated IgG (PAIgG). This method employs an automated through-the-well absorbance spectrophotometer (microplate reader) to directly measure the hemolysis of target indicator cells (IgG-coated sheep erythrocytes) in an assay performed entirely in a 96-well microtiter plate. PAIgG measured by this method in 54 thrombocytopenic patients and 17 controls correlated highly (r = 0.94) with results obtained by the standard tube assay procedure. By substantially simplifying the performance of the QACA and increasing its sensitivity by nearly 1 order of magnitude, this method permits the rapid quantitative determination of PAIgG on platelets obtained from as little as 1 to 4 ml of whole blood.
mesh_terms: D001331:Automation; D001792:Blood Platelets / Q000276:immunology*; D003298:Coombs Test / Q000379:methods*; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis*; D011696:Purpura, Thrombocytopenic / Q000175:diagnosis / Q000276:immunology; D013053:Spectrophotometry; D013921:Thrombocytopenia / Q000175:diagnosis / Q000276:immunology
chemical_list: D007074:Immunoglobulin G