In 2007 a genome wide association analyses revealed an additional risk-associated genetic region in rheumatoid arthritis (RA), the tumor necrosis factor receptor-associated factor 1-complement 5 (TRAF1-C5) containing locus on chromosome 9, comprehensive evaluation of the TRAF1 in RA patients remains necessary.
Serum was obtained from 79 RA patients and from 38 healthy individuals. Concentrations of TRAF1 were measured by enzyme-linked immune sorbent assay (ELISA).
We found that the serum concentration of TRAF1 in RA patients was 35.9±51.2pg/ml, the serum concentration of TRAF1 in healthy controls was 12.5±8.6pg/ml. The difference between these 2 groups was significant (p=0.003). Patients with high disease activity had significantly higher TRAF1 concentration in comparison to patients with low and moderate disease activity (p<0.05). We also found that the numerical DAS28 had a significant positive correlation with TRAF1 concentration (r=0.419, p<0.001). We found that serum GPI and RF concentrations showed a significant positive correlation with TRAF1 concentrations respectively (r=0.767, p<0.001; r=0.365, p=0.001), while CCP concentration showed no significant correlation.
TRAF1 plays a crucial role in the pathogenesis of autoantibodies and may serve as a serologic inflammatory marker of disease activity in RA patients.