However, HIV-related cHL features a higher number of HRS cells, frequent co-infection with EBV, a “sarcomatoid” pattern, and distinct microenvironmental changes, including reduced CD4+ T-cell counts, an inverted CD4/CD8 T-cell ratio, a reduction in infiltrating GrB+ cells (activated cytotoxic cells), and an increase in infiltrating TIA+ T-cells (primarily non-activated cytotoxic cells) were noted. The gene discussed is CD4; the disease is coinfection.