Likewise, the negative roles of Fli1 in CD8+ T cells mediating protective immunity against infections and cancers was validated through Fli1-deficiency mice models [124], and SOCS1 as negative checkpoint of CD4+ T cells survival and effector function was validated by C57BL/6 mice with Marilyn CD4+ T cells [97]. The gene discussed is FLI1; the disease is infection.