Davey M P, Korngold L
J Immunol Methods. 1981;44(1):87-100. doi: 10.1016/0022-1759(81)90110-1.
A solid-phase monoclonal rheumatoid factor (mRF) assay for circulating immune complexes (IC) is described. Microtiter plates are coated with mRF, serum diluted 1 : 40 is added, and complexed IgG is detected with protein A coupled to peroxidase. Selective binding was obtained with aggregated human gamma-globulin and soluble IC prepared in vitro. Sucrose density gradient ultracentrifugation studies indicate that mRF binds intermediate-size IC (between 7S and 19S). Abnormal levels of IC were found in 78% of sera from patients with rheumatoid arthritis, 67% with systemic lupus erythematosus, and 87% with subacute bacterial endocarditis.