IMMUNOFLUORESCENCE STUDIES FOR IMMUNOGLOBULINS AND COMPLEMENT C3 IN SYNOVIAL JOINT MEMBRANES IN PSORIATIC-ARTHRITIS

Abstract

Synovial tissues from 15 patients with psoriatic arthritis were investigated with direct immunofluorescence staining for immunoglobulins (IgG, IgA and IgM) and from 8 patients for complement component C3. As control goups, there were synovial tissues from 7 patients with seropositive rheumatoid arthritis and 5 patients with meniscal tears. In psoriatic arthritis, Ig were found in plasma cells in 93% of the cases, always with the presence of IgG (93%) but also with IgA (47%) and IgM (7%). C3 could not be demonstrated. In seropositive rheumatoid arthritis IgG was demonstrated in all patients (100%), often together with IgA (43%) and IgM (57%). C3 was found in all of these patients. In patients with meniscal tears neither Ig nor C3 could be found. The present findings indicate immunological activity in synovial joint membranes in psoriatic arthritis. The low amount of IgM and the lack of C3 suggest a difference compared to seropositive rheumatoid arthritis.