We found the frequencies of circulating IFN-γ−IL-17−IL-22+ (Th22), IFN-γ−IL-17+ (total Th17), IFN-γ+IL-17−IL-22+ (IL-22+Th1) cells, and IFN-γ−IL-17+IL-22+ (IL-22+Th17) cells, as well as the plasma levels of IL-22, IL-17 and IFN-γ to be significantly reduced in RA patients that responded to treatment, but not in non-responders. Here, IL17A is linked to rheumatoid arthritis.