Composition of T and NK cells immune cell types in patients with CLL remains unchanged after short-term venetoclax treatment. (A) Schematic representation of the CLL study. PB samples from 19 patients with CLL were collected before (pre) and after (post) 1 month of venetoclax treatment and analyzed by CyTOF. (B) UMAP projections of PB cells, colored by FlowSOM clusters with key immune cell types annotated. (C) UMAP of PB cells from patient CLL_028 pre- and postvenetoclax treatment. (D) Concentrations of CLL, NK, and T-cell subsets. (E) Mean expression of survival and checkpoint proteins expressed as a ratio of postvenetoclax:prevenetoclax treatment in CD4⁺ and CD8⁺ T cells. Each symbol represents an individual patient; paired t test; ∗P < .05, ∗∗P < .01. (F) Representative histograms of BCL-2, BCL-XL, MCL-1, CTLA-4, PD-1, TIM3, PD-L1, CD27, and OX40 protein pre- and postvenetoclax treatment in CD4 naïve (N) (CD45RA^highCD27^high), EM CD4, CD8 naïve (CD45RA^highCD27^high), and EM CD8 cells from patient CLL_025. CM, central memory.