Monocyte receptor function in patients with rheumatoid arthritis.

Monocytes from patients with rheumatoid arthritis (RA), osteoarthritis (OA), and normal volunteers were studied for abnormalities of Fc and C3 receptor function. Monocytes from the majority of 22 patients with active RA showed enhanced E-rosette formation and Ea phagocytosis compared to monocytes from 20 normal volunteers and 10 OA patients, However, no significant differences in binding of EAC or uptake of iodinated aggregated gamma globulin were found among the 3 groups. Corticosteroid-treated RA patients exhibited significant depression of EA-rosette formation and phagocytosis. These results suggest that there is modulation of EA receptor function in monocytes from RA patients.