To investigate the hypothesis that soluble E-selectin (sE-selectin) may be detected in synovial fluid (SF) and play a role in inflammatory arthritis.
We used a sandwich ELISA to measure sE-selectin in the SF of 58 patients with rheumatoid arthritis (RA), 9 with psoriatic arthritis (PsA), 30 with osteoarthritis (OA), 13 with gout, and 9 with calcium pyrophosphate dihydrate crystal deposition disease (CPPD).
SF sE-selectin values in RA (mean 1.49 ng/ml, 0.18-3.90) and PsA (mean 1.36 ng/ml, 0.88-2.31) were significantly higher than those with OA (mean 0.83 ng/ml, 0.00-1.83), gout (mean 1.04 ng/ml, 0.11-3.42), or CPPD (mean 0.80 ng/ml, 0.20-1.47). Elevated SF sE-selectin was associated with elevated serum sE-selectin, erythrocyte sedimentation rate, and SF white blood cell count.
Our findings suggest that endothelial cell activation and E-selectin may contribute to the development of inflammatory processes.