CD4 and rheumatoid arthritis: Secondarily, we found that rs878081 and rs1055311 are genotypically associated with ESR and aCCP levels, respectively, in an RA population, providing further evidence that the lack of neonatal negative selection of self-reactive CD4+ T-cells against citrullinated peptides may lead to significantly higher disease activity and may explain the age-related aggregation of citrullination and autoantibodies [70].