Impaired blastogenic response of lymphocytes from synovial fluid and peripheral blood of patients with rheumatoid arthritis.

: Synovial fluid lymphocytes from patients with rheumatoid arthritis demonstrated a markedly diminished blastogenic response to both phytohemagglutinin and pokeweed mitogens, when compared to normal peripheral blood lymphocytes. The blastogenic response to rheumatoid peripheral blood lymphocytes to both mitogens was also depressed, when compared to the response of normal lymphocytes, but the difference was less marked and was within limits which could be accounted for by recent salicylate therapy. Lymphocytes of both peripheral blood and synovial fluid of rheumatoid patients showed a delayed response to PHA (five days to achieve maximum thymidine incorporation vs four days for normals).