CD4 and HIV infectious disease: Despite evidence of well-controlled HIV infection as evidenced by undetectable HIV RNA and preserved peripheral blood CD4+ cell counts in the vast majority of patients, we found that the tumour microenvironment of HIV-associated HCC patients was characterised by stronger tumoural PD-L1 expression and denser intratumoural CD8+/PD-1+ and CD4+/FOXP3+ cell infiltration, suggesting evidence of more profound T cell dysfunction in HIV+ cases compared with controls.