CD4 and Autoimmunity: Hence, HTLV-1-induced changes in regulatory CD4 T-cell molecules activity affects the homeostasis of cytokines such as IFN-γ, TNF-α, TGF-β, and IL-10, which disrupts the balance in anti-inflammatory and inflammatory responses, resulting in the loss of tolerance and the development of autoimmunity (Quaresma et al., 2016).