CD4 and rheumatoid arthritis: There were no significant differences either in the number or in the percentage of circulating T-lymphocytes or CD4+T-lymphocytes between RA patients and HCs at baseline (T-lymphocytes: 2801.99 ± 380.15 vs. 2002.15 ± 347.12 cells/μL and 49.47 ± 2.52 vs. 52.88 ± 5.95%; CD4+ T-lymphocytes: 1131.60 ± 174.23 vs. 825.20 ± 79.84 cells/μL and 37.13 ± 2.17 vs. 40.29 ± 4.69%, respectively).