More recently, Lombardi et al. were able to generate a good manufacturing practice (GMP)-compatible protocol for the expansion of pediatric thymus-derived CD3 + CD4 + CD25 + CD127- (Tregs) as well as CD3 + CD4 + CD25 + CD127- CD45RA + (RA + Tregs) cells, paving the way for future clinical application [53]. This evidence concerns the gene CD4 and rheumatoid arthritis.