CD19 CAR-T cells have led to durable remissions in patients with refractory B-cell malignancies; nevertheless, most patients eventually relapse in the long term. Many interventions aimed at improving current products have been reported, with a subset of them focusing on a direct or indirect link to the metabolic state of the CAR-T cells. We assessed clinical products from an ongoing clinical trial utilizing CD19-28z CAR-T cells from patients with acute lymphoblastic leukemia. CAR-T clinical products leading to a complete response had significantly higher mitochondrial function (by oxygen consumption rate) irrespective of mitochondrial content. Next, we replaced the carbon source of the media from glucose to galactose to impact cellular metabolism. Galactose-containing media increased mitochondrial activity in CAR-T cells, and improved in in-vitro efficacy, without any consistent phenotypic change in memory profile. Finally, CAR-T cells produced in galactose-based glucose-free media resulted in increased mitochondrial activity. Using an in-vivo model of Nalm6 injected mice, galactose-primed CAR-T cells significantly improved leukemia-free survival compared to standard glucose-cultured CAR-T cells. Our results prove the significance of mitochondrial metabolism on CAR-T cell efficacy and suggest a translational pathway to improve clinical products.

CD19 CAR-T 细胞已使难治性 B 细胞恶性肿瘤患者获得持久缓解；然而，从长远来看，大多数患者最终会复发。已报道了许多旨在改进现有产品的干预措施，其中一部分重点关注与 CAR-T 细胞代谢状态的直接或间接联系。我们评估了一项正在进行的临床试验的临床产品，该试验利用来自急性淋巴细胞白血病患者的 CD19-28z CAR-T 细胞。无论线粒体含量如何，导致完全缓解的 CAR-T 临床产品都具有显着更高的线粒体功能（按耗氧率计算）。接下来，我们将培养基的碳源从葡萄糖替换为半乳糖，以影响细胞代谢。含半乳糖的培养基增加了 CAR-T 细胞中的线粒体活性，并提高了体外功效，而记忆特征没有任何一致的表型变化。最后，在基于半乳糖的无葡萄糖培养基中产生的 CAR-T 细胞导致线粒体活性增加。使用注射 Nalm6 的小鼠体内模型，与标准葡萄糖培养的 CAR-T 细胞相比，半乳糖引发的 CAR-T 细胞显着提高了无白血病生存率。我们的结果证明了线粒体代谢对 CAR-T 细胞功效的重要性，并提出了改进临床产品的转化途径。