A, UMAP projection of single cell RNA sequencing of control and TLE4KO CAR T cells both before and after stimulation with GSCs. Cluster assignments for the overall population are shown. B, Cluster composition of unstimulated vs. unstimulated control or TLE4KO cell populations. C, Population distribution of control and TLE4KO CAR T cells before and after stimulation. D, Characterization of clusters based upon cell proliferation. Top: Violin plot of MKI67 expression. Middle: Dot plot of CD4 vs. CD8A expression wherein larger dots indicate a higher proportion of cells with expression and red vs. blue fill indicates higher expression. Heatmap: Scaled expression of T cell markers including costimulatory, activation, naive, exhaustion and regulatory T cell markers as well as AP1 signaling. Bottom: Proportion of cells in each cluster under stimulated vs. unstimulated conditions in control (blue) or TLE4KO (red) populations. Positive values indicate increase in cluster occupancy following stimulation. E-H, Expression of CCL3 (E), TNFRSF4 (F), IFNG (G) and BCAT1 (H) in control or TLE4KO CAR T-cells superimposed on the UMAP projection.