IFNG and rheumatoid arthritis: A preclinical study by Luo et al. found that the intervention of IGU plus MTX could remarkably inhibit infiltration of inflammatory cells into the synovium, and suppressed production of cytokines (IL-17, IFN-γ, IL-6, and TNF-α) and antibodies (IgG and IgG2b) in serum in the mice with collagen-induced arthritis which is widely used in preclinical studies of RA [49].