Duvelisib added during CART cell culture enriched CD8+ T_SCM, naive, and central memory CD8⁺ CART cells and modulated CD4⁺ T helper cell polarization. Isolated CD3⁺T-cells from 3 patients with CLL were transduced with anti-CD19 CAR using a multiplicity of infection of 30 and cultured for 14 days, with or without 300 nM duvelisib, to yield control CART cells and Duv-CART cells. Mass cytometry by time of flight analysis was performed, and tSNE was used to reduce all phenotypic data into 2 dimensions, tSNE1 and tSNE2. (A) A representative viSNE plot from 1 of the 3 CLL samples analyzed. (B) Unsupervised FlowSOM showing 10 qualitative clusters. Changes in the size of a given cluster denote differences between control CART cells (0.1% DMSO) and Duv-CART cells. Th1 was defined as CD4⁺CXCR3⁺ and Th2 as GATA3⁺CXCR4⁺. (Confirmatory cytokine expression studies were not performed.) (C) Differences in levels of CART cell phenotypes assessed by CITRUS analysis. **P ≤ .01; ns, not significant. tSNE, t-distributed stochastic neighbor embedding; viSNE, visualization SNE.