CD4^dimCD8^bright T cells are highly enriched for antigen-specific responses in comparison to CD4⁻CD8⁺ T cells. (A-D) Cumulative data showing percentage of total tetramer binding (antigen recognition; A-B) and total CD107ab staining (cytotoxic potential; C-D) of CD4⁻CD8⁺ and CD4^dimCD8^bright T cells from HIV⁺ LTNP (left) and CMV⁺ (right) donors. Data are based on at least 3 donors.