Changes in the frequency and phenotype of peripheral T cell subpopulations (a decrease in naive T cells, an increase in memory T cells, loss of the co-stimulatory molecule CD28, contraction of the TCR repertoire), the reduced output of TREC+ thymic recent emigrants and telomere erosion (naive and memory T cells and granulocytes) are hallmarks of the RA immunosenescence fingerprint [113]. This evidence concerns the gene CD28 and rheumatoid arthritis.