[Mononucleated phagocytes from rheumatoid synovial fluid. Synthesis of prostanoids and first pharmacological...

An original and easily reproducible technique for isolating and culturating mononucleated phagocytes from rheumatoid synovial fluid was used by the authors to study the synthesis of PGE2, PGF alpha 2 and TxB2 by macrophages taken from 16 patients with rheumatoid arthritis. The functional importance of these macrophages was evaluated by comparing their ratios of prostaglandin synthesis. PGE2 and TxB2 are released in large quantities and are increased after stimulation with zymosan. Two distinct cell populations having different biochemical characteristics were identified from these macrophages based on their capacity to synthesize prostaglandins. Prostaglandin synthesis was correlated with the clinical progression of rheumatoid arthritic disease as evaluated by Lee's index and the time required to loosen up morning joint stiffness in these patients. No correlation was found between prostaglandin synthesis and the quantity of synovial fluid in the affected joint. The first results of a pharmacological study evaluating the activity of non steroid anti-inflammatory drugs using this experimental model are presented here. The addition of indomethacin to culture medium produces dose-dependent inhibition of prostaglandin synthesis.