Complement fixation by rheumatoid factor.

Complement fixation by rheumatoid factor.

The capacity for fixation and activation of hemolytic complement by polyclonal IgM rheumatoid factors (RF) isolated from sera of patients with rheumatoid arthritis and monoclonal IgM-RF isolated from the cryoprecipitates of patients with IgM-IgG mixed cryoglobulinemia was examined. RF mixed with aggregated, reduced, and alkylated human IgG (Agg-R/A-IgG) in the fluid phase failed to significantl...

Negative complement-fixation tests with rheumatoid factor positive sera. A simple method for selective removal of rheumatoid factor.

Sera from patients with rheumatoid arthritis regularly contain inhibitors of complement fixation (CF) to antigen-antibody complexes (Heimer and Levin, 1965). Removal of rheumatoid factor (RF) by absorption of sera with heat-aggregated human y-globulin resulted in a higher number of positives and a rise in CF antibody titre against antigens from herpes simplex, mumps, and morbilli viruses (Stanf...

Rheumatoid Factor, Complement, and Mixed Cryoglobulinemia

Low serum level of complement component 4 (C4) that occurs in mixed cryoglobulinemia (MC) may be due to in vivo or ex vivo activation of complement by the classical pathway. Potential activators include monoclonal IgM rheumatoid factor (RF), IgG antibodies, and the complexing of the two in the cold, perhaps modulated by the rheology and stoichiometry of cryocomplexes in specific microcirculatio...

Complement Fixation by a Two-component Antibody System: Immunoglobulin G and Immunoglobulin M Anti-globulin (rheumatoid Factor)

Complement-mediated lysis of sheep erythrocytes coated with optimal concentrations of rabbit IgG hemolysin was inhibited by euglobulin fractions from the sera of patients with seropositive rheumatoid arthritis. That this was due to direct interaction with the IgG coat on the red cell rather than a nonspecific reaction with complement in the fluid phase was confirmed by controls using cells coat...

Detection of rotavirus by Latex Agglutination Test (Rotales); Comparison with Electron Microscopy and Complement Fixation Test