Ex vivo BrdU incorporation of CD8⁺ T-cell subsets. Freshly isolated PBMCs were incubated with BrdU and processed as described in “Materials and methods.” (A) BrdU staining on total CD8⁺ cells. (B) Distribution of CD8⁺ subsets of total and BrdU⁺ cells. (C) Mean percentage of BrdU⁺ cells in CD8⁺. subsets in 5 healthy donors.