Racah Institute of Physics, The Hebrew University, Jerusalem 91904, Israel.
Jerusalem College of Technology, Jerusalem 91160, Israel.
Cells. 2023 Sep 12;12(18):2261. doi: 10.3390/cells12182261.
T cells expressing chimeric antigen receptors (CARs) are at the forefront of clinical treatment of cancers. Still, the nanoscale organization of CARs at the interface of CAR-Ts with target cells, which is essential for TCR-mediated T cell activation, remains poorly understood. Here, we studied the nanoscale organization of CARs targeting CD138 proteoglycans in such fixed and live interfaces, generated optimally for single-molecule localization microscopy. CARs showed significant self-association in nanoclusters that was enhanced in interfaces with on-target cells (SKOV-3, CAG, FaDu) relative to negative cells (OVCAR-3). CARs also segregated more efficiently from the abundant membrane phosphatase CD45 in CAR-T cells forming such interfaces. CAR clustering and segregation from CD45 correlated with the effector functions of Ca influx and target cell killing. Our results shed new light on the nanoscale organization of CARs on the surfaces of CAR-Ts engaging on- and off-target cells, and its potential significance for CAR-Ts' efficacy and safety.
嵌合抗原受体 (CAR) 表达的 T 细胞是癌症临床治疗的前沿。然而，CAR-T 细胞与靶细胞界面处的 CAR 结构的纳米级组织对于 TCR 介导的 T 细胞激活至关重要，但目前仍知之甚少。在这里，我们研究了针对 CD138 蛋白聚糖的 CAR 在这些为单分子定位显微镜生成的最佳固定和活细胞界面上的纳米级组织。CAR 在纳米簇中表现出显著的自聚集，与靶细胞（SKOV-3、CAG、FaDu）相比，与阴性细胞（OVCAR-3）相比，这种自聚集增强。与形成这种界面的 CAR-T 细胞中丰富的膜磷酸酶 CD45 相比，CAR 也更有效地从 CD45 中分离出来。CAR 聚集和与 CD45 的分离与 Ca2+流入和靶细胞杀伤的效应功能相关。我们的研究结果为 CAR-T 细胞与靶细胞和非靶细胞相互作用表面上的 CAR 结构的纳米级组织及其对 CAR-T 细胞功效和安全性的潜在意义提供了新的认识。
