In Situ Gene Engineering Approach to Overcome Tumor Resistance and Enhance T Cell-Mediated Cancer Immunotherapy

T cell-mediated cancer immunotherapy harnesses the power of cytotoxic T lymphocytes (CTLs) to target and eradicate tumor cells. However, tumor cells often evade immune attack through membrane repair mechanisms involving endosomal sorting complexes required for transport (ESCRT) and immune suppression within the tumor microenvironment. Here, we developed a robust TMV@PpCHIL nanomedicine to address these issues by reprogramming tumor cells via in situ gene editing. Using CRISPR/Cas9, we disrupted the Chmp4b gene, a key component of the ESCRT machinery, preventing tumor cells from repairing CTL-induced membrane damage. Simultaneously, we genetically engineered tumor cells to produce interleukin-12 (IL-12), a cytokine that enhances CTL activation. The TMV@PpCHIL nanomedicine, designed by coating tumor membrane vesicles (TMVs) onto polyamidoamine (PAMAM) dendrimer-condensed plasmid complexes, ensured efficient CRISPR/Cas9-based gene editing and sustained IL-12 production. This approach significantly enhanced CTL-mediated tumor cell cytotoxicity, suppressed tumor growth, reduced metastasis, and prolonged survival, providing a promising strategy for durable cancer treatment.