Cytotoxic and exhausted CD4⁺ CAR T cells harboring interferon gamma signature are identified preferentially in patients with transient response to therapy. (A) Density map of cytotoxicity and exhaustion gene signature scores for CD4⁺ and CD8⁺ CAR T cells, by group. Cell fractions (%) are annotated in each quadrant. (B) Bar plot showing CD4⁺ CAR T-cell fraction (mean % ± SE) of “double positive” cytotoxic and exhausted cells derived from the top right quadrant in panel B, by group. Statistical significance is marked by asterisk and determined by Wilcoxon rank-sum test (P = .03). (C) Box plot showing CAR-Treg fraction (median % ± 1.5 interquartile range), by group. (D) Enrichment score (see “Methods”) for interferon gamma (IFNG) pathway of CD4⁺ CAR T cells from DR group vs TR group. (E) Dot plots showing normalized expression of genes related to interferon (IFNG) pathway in CD4⁺ CAR T cells, by group. Dot size is proportional to fraction of cells.