There were no significant differences in the number or frequency of circulating CD4+T-lymphocytes between MTX nonresponder and MTX responder RA patients and HCs at baseline (CD4+T cells: 821.99 ± 187.91 vs. 1101.54 ± 260.11 cells/μL and 33.07 ± 3.46 vs. 36.22 ± 2.73%, responder vs. nonresponder patients, respectively). This evidence concerns the gene CD4 and rheumatoid arthritis.