[Determination of the concentrations of interleukin-18 and other cytokines in the synovial fluid in patients with osteoarthritis].
OBJECTIVE
To determine the concentrations of interleukin-18 (IL-18), IL-6, IL-8, and prostaglandin E2 (PGE2) in the synovial fluid in patients with osteoarthritis (OA), and explore the role of IL-18 in the pathogenesis of OA.


METHODS
The synovial fluid was collected from 30 patients with knee OA, and the concentrations of IL-18 and the other cytokines were measured using enzyme-linked immunosorbent assay (ELISA). A linear regression was performed between IL-18 and the other cytokines.


RESULTS
The average IL-18 and PGE2 concentrations were 220-/+304 pg/ml and 89-/+104 pg/ml in the synovial fluid, respectively, and the two cytokines showed a positive correlation in the synovial fluid (r=0.628, P=0.001). The IL-18 concentration was also correlated to the concentrations of IL-6 (1200-/+1587 pg/ml, n=22; r=0.590, P=0.008) and IL-8 (5190-/+6024 pg/ml, n=9; r=0.776, P=0.014).


CONCLUSIONS
IL-18 can promote PGE2 production, which causes cartilage degradation in OA, thus therapies targeting this cytokine may prove an effective approach to early OA treatment.
Li
Yong
Y
Department of Orthopedics, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
Jiang
Jian-ming
JM
Yang
De-hong
DH
Wang
Feng-long
FL
Mao
Zhong-xuan
ZX
D000368:Aged; D015232:Dinoprostone / Q000096:biosynthesis; D005260:Female; D006801:Humans; D020382:Interleukin-18 / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000378:metabolism*; D013582:Synovial Fluid / Q000378:metabolism*
D020382:Interleukin-18; D015232:Dinoprostone