Detection of the novel IL-1 family cytokines by QAH-IL1F-1 assay in rheumatoid arthritis.

The interleukin (IL)-1 family of cytokines comprises 11 members, including 7 pro-inflammatory cytokines (IL-1α, IL-1β, IL-18, IL-33, IL-36α, IL-36β,IL-36γ) and 4 anti-inflammatory cytokines (IL-1R antagonist (IL-1Ra), IL-36Ra, IL-37 and IL-38), and play central roles in mediating immune responses. In this study, we detected serum levels of IL-36 subfamily cytokines (including IL-36α, IL-36β, IL-36γ, IL-36Ra and IL-38), IL-37, IL-33 and aimed to investigate the roles of these cytokines in rheumatoid arthritis (RA) preliminarily. A total of 10 RA patients and 10 healthy controls (HCs) were involved in this study, we measured IL-36 subfamily cytokines, IL-37 and IL-33 levels in the serum of the experiment subjects by QAH-IL1F-1 assay. Clinical and laboratory data of the subjects were collected and analyzed by Spearman's rank test. Compared to that of HCs, IL-36α, IL-36β, IL-36Ra, IL-38 and IL-33 levels were significantly increased in RA patients. We also found RA patients with elevated IL-36Ra had a higher ESR and RF-IgM, and there was a positive correlation between increased IL-36α and CRP. Our study suggests that parts of the novel members of IL-1 family cytokines were involved in the pathogenesis of RA, and may provide a novel target for therapies of RA.