Detection of IL-37 in peripheral blood of patients with rheumatoid arthritis and its clinical significance

The study aimed to detect the expression level of interleukin-37 (IL-37) in patients with rheumatoid arthritis (RA) and explore its clinical significance. A total of 40 peripheral blood samples from active and stable RA patients were collected (40 patients with RA), and peripheral blood from 40 healthy volunteers was used as the control group. Peripheral blood serum and peripheral blood mononuclear cells (PBMCs) were isolated. The expression of IL-37 mRNA in PBMCs was detected by real-time fluorescence quantitative PCR. Serum levels of IL-37, rheumatoid factor (RF), and anticyclic citrullinated peptide antibody (CCP) were measured by enzyme-linked immunosorbent assay (ELISA). The results were then calculated and analyzed. The results showed that expression of IL-37 mRNA in the PBMCs of patients with RA was significantly higher than that in the control group (P < 0.05). Expression of IL-37 mRNA in the PBMCs of the active period group was significantly higher than that in the stable period group (P < 0.05). IL-37 levels in patients with RA were significantly higher than those of the control group (P < 0.05). IL-37 levels in the active period group were also significantly higher than those of the stable period group (P < 0.05). The comparative analysis of RF and anti-CCP antibody levels showed that IL-37 was positively correlated with RF and anti-CCP levels in patients with RA. In conclusion, the expression level of IL-37 in peripheral blood of RA patients was significantly higher than that of normal control group, and it was correlated with RF and CCP antibody levels, indicating that IL-37 plays an important role in the development of RA.