Y. Fujikawa et al., INTERLEUKIN-1 RECEPTOR ANTAGONIST PRODUCTION IN CULTURED SYNOVIAL-CELLS FROM PATIENTS WITH RHEUMATOID-ARTHRITIS AND OSTEOARTHRITIS, Annals of the Rheumatic Diseases, 54(4), 1995, pp. 318-320
Objective-To measure the amounts of interleukin-1 receptor antagonist
(IL-1ra) protein produced by cultured synovial cells obtained from pat
ients with rheumatoid arthritis (RA) and osteoarthritis (OA). Methods-
Synovial cells obtained from patients with either RA or OA were cultur
ed and the supernatants were measured for IL-1ra by enzyme linked immu
nosorbent assay. Results-The synovial cells obtained from patients wit
h RA produced significantly smaller amounts of IL-1ra than did those o
btained from patients with OA, in a late passage (third to fifth) with
out stimulation and a first passage both with and without stimulation
(p<0.025, respectively). in addition, when the patients with RA were d
ivided into two groups according to the maximum number of lining cell
layers, the amounts of IL-1ra produced by the proliferative type were
smaller than those produced by the less proliferative type (p<0.025).
Conclusions-The above findings suggest that IL-1ra production in RA sy
novial cells is suppressed, and that reduced IL-1ra protein production
is one of the causes which leads to the proliferation of lining cells
and persistent joint inflammation.