title: Certain rheumatoid factors react with both IgG and an antigen associated with cell nuclei.
abstract: Rheumatoid factors (RF) were isolated by their affinity for human IgG. RF from three out of twenty-four sera (12%) with a RF-latex titre greater than or equal to 20 and an anti-nuclear antibody (ANA) titre greater than or equal to 250 cross-reacted with nuclei from mouse cells. This antibody which represents an unknown proportion of RF, is designated RF/ANA. Only one of the three sera (Nil) contained large amounts of RF/ANA. A fourth serum (Jos) had 6.6 mg of RF per ml and an ANA-titre of 4096; all the ANA-activity of this serum was absorbed by an IgG-agarose conjugate. Part of the RF-activity of serum Jos was carried by antigenically deficient IgM. The ANA-activity of purified RF/ANA from four sera was inhibited by low concentrations of aggregated human IgG and by higher concentrations of human Fcgamma fragments and non-aggreated mouse anti-DNP antibodies. The data provide strong support for the conclusion that certain antibody molecules can combine with both IgG and an antigen in cell nuclei.
mesh_terms: D000974:Antibodies, Antinuclear / Q000032:analysis; D000937:Antigen-Antibody Reactions; D002467:Cell Nucleus / Q000276:immunology*; D002846:Chromatography, Affinity; D003429:Cross Reactions; D005455:Fluorescent Antibody Technique; D006801:Humans; D007106:Immune Sera; D007122:Immunoelectrophoresis; D007074:Immunoglobulin G; D012217:Rheumatoid Factor
chemical_list: D000974:Antibodies, Antinuclear; D007106:Immune Sera; D007074:Immunoglobulin G; D012217:Rheumatoid Factor