Suppression of OAZ expression inhibited downstream ID levels, and secretion of ANA and IL-21, implicating a role of OAZ pathway in the pathogenesis of SLE.
The above results suggest that the elevated production of CXCL13, BAFF, and IL-21 may be associated with the function of T(FH) for the immunopathogenesis in SLE, and CXCL13 may serve as a potential disease marker of SLE.
Recent work has implicated a novel Th effector cell subset, the Th17 cell subset, in the development of both rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) because of the ability of Th17 cells to produce cytokines like IL-17 and IL-21 that can drive both inflammatory and humoral responses.
Recent studies have demonstrated that IL-21 plays an important and non-redundant role in a number of autoimmune animal models indicating that IL-21 could be a common modulator of the adaptive immune response towards self-tissue constituents in diseases such as systemic lupus erythematosus, models of rheumatoid arthritis, multiple sclerosis and type-1 diabetes.
From a clinical standpoint, these results suggest that blocking IL-21 in systemic lupus erythematosus patients may represent a promising novel therapeutic approach.
Finally, BXSB-Yaa mice, which develop a systemic lupus erythematosus-like disease, have greatly elevated IL-21, suggesting a role for IL-21 in the development of autoimmune disease.