CD4 and rheumatoid arthritis: Double-positive IL-17A+/IFN-γ+ CD4+ T-cells have been reported in synovial fluid and synovial tissue of some patients with rheumatoid arthritis (RA)22–24 and are increased in peripheral blood from patients with AS and RA.25 However, we found no evidence of an influence of SNP genotype on the frequency of these cells.