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A solid-phase assay for circulating immune complexes using monoclonal rheumatoid factors and peroxidase-linked protein A.

M P Davey·L Korngold
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Abstract

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.

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Antigen-Antibody ComplexArthritis, RheumatoidBinding SitesBlood PreservationCentrifugation, Density GradientClone CellsEndocarditis, Subacute BacterialHemocyaninsHorseradish PeroxidaseHumansImmunoglobulin GImmunoglobulin MLupus Erythematosus, SystemicRheumatoid FactorStaphylococcal Protein AJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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M P Davey, L Korngold. 1981. A solid-phase assay for circulating immune complexes using monoclonal rheumatoid factors and peroxidase-linked protein A.. https://doi.org/10.1016/0022-1759(81)90110-1

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