Lymphocyte characteristics in rheumatic patients and the effect of azathioprine therapy

Abstract

Abstract T‐ and B‐lymphocytes were enumerated in 46 normal subjects, and in 30 patients with rheumatoid arthritis and 4 with psoriatic arthritis by the following cell markers: spontaneous sheep red blood cell rosettes (early and late), complement‐receptor and aggregated gamma globulin receptor lymphocytes. The results of these studies were compared to those from 6 patients with rheumatoid arthritis and 7 with psoriatic arthritis on varying doses of azathioprine. The proportions of T and B cells in all groups were essentially similar. Neither was there any change in the density gradient distribution and response to stimulation by phytohemagglutinin stimulation. Because azathioprine led to lymphopenia in these patients, it was concluded that immunosuppression was induced by decreasing the absolute numbers of normal T‐ and B‐cells rather than by a selective effect on either one. In contrast some patients with systemic lupus erythematosus on azathioprine had a lower proportion of T‐cells than normal. This was probably independent of the effect of azathioprine.