Nuclei of cultured synovial fibroblasts studied by immunofluorescence and microdensitometry

Two techniques which might be expected to detect alterations in DNA have been used in a comparison of cultured non-rheumatoid and rheumatoid synovial fibroblasts. Microdensitometry showed no alteration in staining affinity for methyl green when two pairs of cultures were compared. There was, however, a minor difference in the predominant staining pattern to a fluorescein conjugated anti-IgM serum when five rheumatoid cultures were compared with five non-rheumatoid cultures after exposure to a serum containing anti-nuclear antibodies.