Study on the role of IL-15 in rheumatoid arthritis

Objective To explore the pathogenesis of rheumatoid arthritis(RA)and its relationship with the disease activity by detecting the interleukin-15(IL-15)level in patients of RA,and also compare the plasma IL-15 level in the RA patients with that in the osteoarthritis(OA)patients.Methods Sixty-eight patients of RA enrolled in the study,conforms to the RA classifica- tion standard by the American Rheumatism Association(ARA),32 patients with knee osteoarthritis(OA)satisfied the primary osteoarthritis of the knee classification standard instituted by ARA,30 normal controls were from the health examinations in our hospital.We detected the plasma IL-15 levels of above groups by the method of competitive enzyme-linked immunosorhent assay (ELISA).Results The levels of plasma IL-15 in RA patients were significantly higher than those in tile healthy controls with sta- tistical significance(P0.01),and also significantly higher than those in the OA group(P0.01).The levels of plasma IL-15 in RA patients with activities were significantly higher than those in RA remission group with statistical significance(P0.01) and were related with disease activity.The levels of plasma IL-15 in RA patients at different X-ray stages were significantly dif- ferent,the levels of IL-15 between phaseⅠand PhaseⅡ,phaseⅡand phaseⅢ,phaseⅢand phaseⅣwere statistically significant (P0.01,P0.01,P0.05).Conclusions IL-15 plays a role in the pathogenesis of RA,and it can be used as an indicator of disease activity.It is also involved in the bone destruction in RA,and can be used as an indicator to tell RA from OA.