NT5E and rheumatoid arthritis: Regarding the expression of Treg markers, the results presented in Figure 2(a) show that iTreg cells that were generated in the presence of IL-2 but in the absence of RA (TIL-2) presented a higher expression of the CD39 ecto-5′-nucleotidase and CTLA-4 compared with the expression observed in Treg cells that were generated in the presence of RA (TRA and TILRA Treg cells).