Nature重磅：新一代in vivo CAR-T诞生！体内定点插入大片段DNA，高效生成CAR-T细胞

Core Viewpoint - CAR-T cell therapy, modified through genetic engineering to express chimeric antigen receptors, has revolutionized cancer treatment, with FDA approval for therapies targeting relapsed or refractory cancers such as leukemia, lymphoma, and multiple myeloma. Recent advancements also show potential in treating autoimmune diseases like systemic lupus erythematosus [3][4]. Group 1: In Vivo CAR-T Technology - The in vivo CAR-T technology aims to overcome the limitations of traditional CAR-T cell manufacturing, which is time-consuming and costly. Current methods either rely on transient expression or non-specific DNA integration [3][4]. - A novel dual-vector system has been developed, utilizing enveloped delivery vectors (EDV) and adeno-associated viruses (AAV) to deliver CRISPR-Cas9 and CAR templates, respectively, allowing for efficient and specific integration of CAR into the TRAC locus of T cells [4][7]. Group 2: Technical Optimizations - The research team implemented three key optimizations to enhance the efficiency and safety of in vivo editing: 1. AAV was engineered to resist neutralizing antibodies in human serum, ensuring effective CAR delivery [9]. 2. EDV was modified to display anti-CD3 antibodies, allowing precise targeting of T cells and promoting their proliferation for favorable gene editing conditions [10]. 3. The optimized AAV-hT7 vector minimizes infection of hematopoietic stem cells and tumor cells, reducing potential risks associated with off-target gene editing [10]. Group 3: Experimental Validation - In humanized mouse models, the optimized EDV/AAV dual-vector system successfully generated a significant number of CAR-T cells, comprising nearly 20% of splenic T cells. These CAR-T cells achieved complete B cell clearance in models of B cell developmental deficiency and effectively controlled tumor growth in models of B-cell acute lymphoblastic leukemia, multiple myeloma, and sarcoma [12][13]. - The CAR-T cells generated in vivo exhibited high proliferation and maintained memory cell characteristics, indicating potential for durable therapeutic effects [13]. Group 4: Significance and Outlook - This research marks a significant advancement in the field of in vivo CAR-T technology, enabling targeted integration of large DNA fragments into primary human T cells. The potential advantages include: - Simplified manufacturing processes, reducing costs and time by eliminating complex cell separation and expansion [15]. - Increased accessibility, potentially offering a "ready-to-use" therapy for a broader patient population [15]. - Enhanced safety through precise T cell-specific editing, lowering the risk of off-target effects [15]. - The findings are expected to significantly impact the design and implementation of cell therapy trials, improving patient access to cutting-edge CAR-T cell treatments [16].