TCF7 and HIV infectious disease: During HIV infection, downregulation of TCF1 is associated with impaired mitochondrial function, which further compromises T-cell proliferative capacity and immune responses (68).Research has shown that TCF7-positive ancestral exhausted T cells in T-cell/histiocyte-rich large B-cell lymphoma can predict better responses to PD-1/PD-L1 blockade therapy (69).