Early expansion and long-term persistence predict efficacy of chimeric antigen receptor T cells (CARTs)^{1,2,3,4,5,6,7}, but mechanisms governing effector versus memory CART differentiation and whether asymmetric cell division induces differential fates in human CARTs remain unclear. Here we show that target-induced proximity labelling enables isolation of first-division proximal-daughter and distal-daughter CD8 CARTs that asymmetrically distribute their surface proteome and transcriptome, resulting in divergent fates. Target-engaged CARs remain on proximal daughters, which inherit a surface proteome resembling activated-undivided CARTs, whereas the endogenous T cell receptor and CD8 enrich on distal daughters, whose surface proteome resembles resting CARTs, correlating with glycolytic and oxidative metabolism, respectively. Despite memory-precursor phenotype and in vivo longevity, distal daughters demonstrate transient potent cytolytic activity similar to proximal daughters, uncovering an effector-like state in distal daughters destined to become memory CARTs. Both partitioning of pre-existing transcripts and changes in RNA velocity contribute to asymmetry of fate-determining factors, resulting in diametrically opposed transcriptional trajectories. Independent of naive, memory or effector surface immunophenotype, proximal-daughter CARTs use core sets of transcription factors known to support proliferation and effector function. Conversely, transcription factors enriched in distal daughters restrain differentiation and promote longevity, evidenced by diminished long-term in vivo persistence and function of distal-daughter CARTs after IKZF1 disruption. These studies establish asymmetric cell division as a framework for understanding mechanisms of CART differentiation and improving therapeutic outcomes.

早期扩增和长期持续存在可预测嵌合抗原受体 T 细胞 （CART） 的疗效^{1,2,3,4,5,6,7}，但控制效应子与记忆 CART 分化的机制以及不对称细胞分裂是否诱导人类 CART 的差异命运仍不清楚。在这里，我们表明靶标诱导的邻近标记能够分离第一分裂的近端子级和远端子级 CD8 CART，这些 CART 不对称地分布其表面蛋白质组和转录组，从而导致不同的命运。靶标参与的 CAR 保留在近端子细胞上，其继承了类似于活化未分裂的 CART 的表面蛋白质组，而内源性 T 细胞受体和 CD8 在远端子细胞上富集，其表面蛋白质组类似于静息 CART，分别与糖酵解和氧化代谢相关。尽管具有记忆前体表型和体内寿命，但远端女儿表现出类似于近端女儿的瞬时有效溶细胞活性，在注定要成为记忆 CART 的远端女儿中发现了效应样状态。预先存在的转录本的分配和 RNA 速度的变化都会导致命运决定因子的不对称，从而导致截然相反的转录轨迹。独立于初始、记忆或效应表面免疫表型，近端子 CART 使用已知支持增殖和效应子功能的核心转录因子集。相反，远端子细胞中富集的转录因子抑制分化并促进长寿，IKZF1 破坏后远端子 CART 的长期体内持久性和功能降低证明了这一点。 这些研究将不对称细胞分裂确立为理解 CART 分化机制和改善治疗结果的框架。