B-ALL 患者中 CAR-T 细胞的功能多样化与动态变化

Understanding of cellular evolution and molecular programs of chimeric antigen receptor-engineered (CAR)-T cells post-infusion is pivotal for developing better treatment strategies.

Here, we construct a longitudinal high-precision single-cell transcriptomic landscape of 7,578 CAR-T cells from 26 patients with B cell acute lymphoblastic leukemia (B-ALL) post-infusion.

We molecularly identify eight CAR-T cell subtypes, including three cytotoxic subtypes with distinct kinetics and three dual-identity subtypes with non-T cell characteristics. Remarkably, long-term remission is coincident with the dominance of cytotoxic subtypes, while leukemia progression is correlated with the emergence of subtypes with B cell transcriptional profiles, which have dysfunctional features and might predict relapse.

We further validate in vitro that the generation of B-featured CAR-T cells is induced by excessive tumor antigen stimulation or suppressed TCR signaling, while it is relieved by exogenous IL-12.

Moreover, we define transcriptional hallmarks of CAR-T cell subtypes and reveal their molecular changes along computationally inferred cellular evolution in vivo. Collectively, these results decipher functional diversification and dynamics of peripheral CAR-T cells post-infusion.