A quantitative assay for IgA rheumatoid factor.

W J Koopman; R E Schrohenloher; A Solomon

doi:10.1016/0022-1759(82)90306-4

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A quantitative assay for IgA rheumatoid factor.

W J Koopman·R E Schrohenloher·A Solomon

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Abstract

We developed a solid-phase radioimmunoassay capable of detecting nanogram quantities of human IgA rheumatoid factor (RF) in biological fluids. Human IgM RF, IgG RF, IgG, IgA, IgM and whole serum did not significantly interfere with the IgA RF assay. Patients with sero-positive rheumatoid arthritis (RA) had significantly higher concentrations of IgA RF than sero-negative RA patients or healthy adult controls. Concentrations of IgA RF in paired sera and synovial fluids from sero-positive RA patients were comparable. Levels of IgA RF demonstrated a moderately good correlation with levels of IgM RF in sero-positive RA sera (r = 0.673). However, the ratio of IgA RF concentration to IgM RF concentration in sero-positive RA sera varied widely.

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Antibody Specificity Arthritis, Rheumatoid Binding Sites, Antibody Humans Immunoglobulin A Immunoglobulin Fab Fragments Immunoglobulin Fc Fragments Immunoglobulin G Immunoglobulin M Rheumatoid Factor Synovial Fluid Journal Article Research Support, U.S. Gov't, P.H.S.

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W J Koopman, R E Schrohenloher, A Solomon. 1982. A quantitative assay for IgA rheumatoid factor.. https://doi.org/10.1016/0022-1759(82)90306-4

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