Naïve CD4+ T cells are also able to develop into natural Treg cells (nTreg) in the thymus and differentiate into induced regulatory T cells (iTreg) in the presence of T cell receptor (TCR) and transforming growth factor beta (TGFβ) stimulation to maintain immune balance, preventing the occurrence of autoimmune diseases (Caza and Landas, 2015). Here, CD4 is linked to autoimmune disease.