Division of Oncology, Children's Hospital of Philadelphia.
Center for Data Driven Discovery in Biomedicine, Children's Hospital of Philadelphia; Division of Neurosurgery, Children's Hospital of Philadelphia.
J Vis Exp. 2023 Feb 24(192). doi: 10.3791/64886.
Pediatric CNS tumors are responsible for the majority of cancer-related deaths in children and have poor prognoses, despite advancements in chemotherapy and radiotherapy. As many tumors lack efficacious treatments, there is a crucial need to develop more promising therapeutic options, such as immunotherapies; the use of chimeric antigen receptor (CAR) T cell therapy directed against CNS tumors is of particular interest. Cell surface targets such as B7-H3, IL13RA2, and the disialoganglioside GD2 are highly expressed on the surface of several pediatric and adult CNS tumors, raising the opportunity to use CAR T cell therapy against these and other surface targets. To evaluate the repeated locoregional delivery of CAR T cells in preclinical murine models, an indwelling catheter system that recapitulates indwelling catheters currently being used in human clinical trials was established. Unlike stereotactic delivery, the indwelling catheter system allows for repeated dosing without the use of multiple surgeries. This protocol describes the intratumoral placement of a fixed guide cannula that has been used to successfully test serial CAR T cell infusions in orthotopic murine models of pediatric brain tumors. Following orthotopic injection and engraftment of the tumor cells in mice, intratumoral placement of a fixed guide cannula is completed on a stereotactic apparatus and secured with screws and acrylic resin. Treatment cannulas are then inserted through the fixed guide cannula for repeated CAR T cell delivery. Stereotactic placement of the guide cannula can be adjusted to deliver CAR T cells directly into the lateral ventricle or other locations in the brain. This platform offers a reliable mechanism for the preclinical testing of repeated intracranial infusions of CAR T cells and other novel therapeutics for these devastating pediatric tumors.
小儿中枢神经系统肿瘤是导致儿童癌症相关死亡的主要原因，尽管化疗和放疗有所进展，但预后仍较差。由于许多肿瘤缺乏有效的治疗方法，因此迫切需要开发更有前途的治疗选择，如免疫疗法；针对中枢神经系统肿瘤的嵌合抗原受体 (CAR) T 细胞疗法的使用尤其受到关注。细胞表面靶标，如 B7-H3、IL13RA2 和二唾液酸神经节苷脂 GD2，在几种小儿和成人中枢神经系统肿瘤的表面高度表达，为针对这些和其他表面靶标使用 CAR T 细胞疗法提供了机会。为了评估 CAR T 细胞在临床前小鼠模型中的重复局部递药，建立了一种留置导管系统，该系统重现了目前正在人类临床试验中使用的留置导管。与立体定向递送不同，留置导管系统允许在不使用多次手术的情况下重复给药。本方案描述了在固定导向套管内进行肿瘤内放置，该固定导向套管已成功用于在小儿脑肿瘤的原位模型中测试连续 CAR T 细胞输注。在肿瘤细胞原位注射和植入小鼠后，在立体定向仪器上完成固定导向套管的肿瘤内放置，并通过螺丝和丙烯酸树脂固定。然后通过固定导向套管插入治疗套管，以重复进行 CAR T 细胞递药。导向套管的立体定向放置可以调整为将 CAR T 细胞直接递送至侧脑室或大脑的其他部位。该平台为针对这些毁灭性小儿肿瘤的 CAR T 细胞和其他新型治疗药物的临床前重复颅内输注提供了可靠的机制。
