Expression levels of IL-15 and IL-17 in synovial fluid of rheumatoid arthritis animal model

The aim of the present study was to investigate the expression levels of interleukin-15 (IL-15) and interleukin-17 (IL-17) in synovial fluid of rheumatoid arthritis (RA) animal model, and to investigate their correlations with RA. A total of 100 Wistar rats were selected, among which 60 rats were used to establish the collagen II-induced arthritis (CIA) model as the model observation group, and the remaining 40 rats were used as blank control group. The levels of IL-15 and IL-17 in synovial fluid were detected via enzyme-linked immunosorbent assay (ELISA) at 1, 7, 14, 21 and 28 days after successful modeling. RA was evaluated by using arthritis index (AI) and pedal swelling volume. The expression levels of IL-15 and IL-17 in synovial fluid of rats in model observation group were higher than those in blank control group (P<0.05), and the levels of IL-15 and IL-17 in model observation group were gradually increased over time. In model observation group at 7 days after modeling, AI and pedal swelling volume began to be increased gradually reaching a peak at 28 days. The pedal swelling volume of CIA model rats was significantly higher than that of the blank control group (P<0.05). The increased expression levels of IL-15 and IL-17 in synovial fluid of rats in the CIA model observation group are correlated with the activity of disease, which can be used as reference indexes for the activity of RA.