Higher quantities of PD1⁺ TIM3⁺ effector-like CD8⁺ CAR-Ts correlate with severe ICANS in CR. Patients who achieved CR (n = 16) were separated into a severe ICANS (grade 3-4) cohort (n = 4) and a no/nonsevere ICANS (grade 0-2) cohort (n = 12). (A) Day-14 postinfusion PBMCs were analyzed by spectral flow cytometry and dimensional reduction. Individual patient UMAPs of CAR⁺ CD8⁺ T-cell clusters in ICANS (left) vs no/nonsevere ICANS cohorts (right) are shown, colored by cluster. Largest cross sectional tumor diameter before CAR-T infusion is listed underneath patient identifying numbers. Box plots in panels B and C compare characteristics in severe ICANS vs no/nonsevere ICANS cohorts. (B) Combined clusters 11 and 12, reported as a percent of CAR⁺ CD8⁺ T cells. (C) PD-1⁺ TIM3⁺ T-bet⁺ GZMB⁺ cells quantified by 2D flow analysis, reported as a percentage of CAR⁺ CD8⁺ cells. Box plots show quartiles with bands at the median; whiskers indicate 1.5 interquartile range; all observations overlaid as dots. P values are from linear regression analysis; ∗P < .05, ∗∗P < .01; ∗∗∗P < .001. Pt, Patient.