CTLA4 and rheumatoid arthritis: Similarly, the expression levels of CTLA4 [40.40 (27.40–54.00) % vs. 70.50 (60.25–74.35) %; p < 0.01] and GITR [35.92 (27.18–61.66) % vs. 75.03 (64.58–76.91) %; p < 0.01] in CD4+CD25+Foxp3+ Tregs were significantly decreased in RA patients compared with HCs.