Anti-RANA antibody in rheumatoid arthritis, seronegative polyarthritis, and normal controls

Summary

Anti-RANA antibody was found in 76% and 69% of seropositive and seronegative rheumatoid patients. No correlation appeared between this antibody, rheumatoid factor or a positive fluorescent anti-nuclear antibody (FANA). Many sera from healthy individuals, paritcularly medical personnel, and other disease groups demonstrated the fine nuclear speckling by immunofluorescence on Raji cells, but with weaker fluorescence. Anti-IgG conjugate was more sensitive in detecting the presence of the antibody in these sera. The presence of other antibodies producing a diffuse nuclear fluorescent pattern on Raji cells made it difficult to assess underlying fine nuclear speckling. Many of these sera produced a positive FANA on rat liver substrate. Very little variation in anti-RANA antibody status occurred with time and any change that did occur did so independently of rheumatoid factor. In view of the presence of anti-RANA antibody in the sera of patients with a variety of underlying rheumatic disorders and in normal individuals, the exact role of the antibody in the pathogenesis or diagnosis of rheumatoid arthritis is in doubt.