局部区域输送嵌合抗原受体（CAR）修饰的T（CAR-T）细胞已成为治疗脑肿瘤的一种有希望的策略。然而，复杂的细胞外制造程序和疾病快速进展限制了其更广泛的应用。巨噬细胞（MΦ）表现出独特的效应功能和高度的浸润性，特别是在脑部的固体肿瘤微环境（TME）中，其中巨噬细胞作为结构支持和中枢神经系统的主要免疫效应细胞等于5-12％的脑细胞。在这里，我们报告了一种用于原位基因编辑肿瘤内MΦ的合成通用DNA纳米载体，并携带一个ErbB2特异性CAR，以指导它们的吞噬活性朝向肿瘤，进而引发局部区域的抗肿瘤免疫反应。具体来说，我们证明当局部区域输送时，位于纳米粒子外壳中的RP-182肽可以靶向MΦ，并重新编程类M2肿瘤相关巨噬细胞（TAM）至类M1抗肿瘤表型。随后，可以使用负载CAR基因的DNA纳米复合物来引入ErbB2靶向CAR，生成的CAR-MΦ将充当“活体”治疗药物，因此连续清除侵袭性肿瘤细胞。我们的工作展示了一种实际的脑干胶质瘤（BSGs）抗肿瘤免疫治疗方法，可广泛地应用于患有其他ErbB2阳性实体恶性肿瘤的患者。©2023作者。

Locoregional delivery of chimeric antigen receptor (CAR)-modified T (CAR-T) cells has emerged as a promising strategy for brain tumors. However, the complicated ex vivo cell manufacturing procedures and the rapid progression of the disease have limited its broader applications. Macrophages (MΦs) exhibit unique effector functions and a high degree of infiltration within the solid tumor microenvironment (TME), especially in the brain, where MΦs function as structural support, and the main immune effector cells of the CNS represent 5-12% of brain cells. Here, we report a synthetic universal DNA nanocarrier for in situ genetic editing of intratumoral MΦs with an ErbB2-specific CAR to direct their phagocytic activity towards tumors and subsequently initiate a locoregional antitumor immune response. Specifically, we demonstrated that when delivered locoregionally, the RP-182 peptide, located in the shell of a nanoparticle, targeted MΦs and reprogrammed M2-like tumor-associated macrophages (TAMs) to an antitumor M1-like phenotype. Subsequently, the CAR gene-laden DNA nanocomplex can be used to introduce ErbB2-targeted CAR, and the generated CAR-MΦs then act as "living" cures, thereby serially clearing the invasive tumor cells. Our work demonstrates a practical antitumor immunotherapy for brainstem gliomas (BSGs) that may be broadly applicable for patients suffering from other ErbB2-positive solid malignancies.© 2023. The Author(s).