A collaborative team from the University of California, San Francisco, has pioneered a revolutionary ‘in-body drug factory’ technology. This innovation circumvents the lengthy and expensive ex vivo production process inherent in traditional CAR-T therapy by directly ‘transforming’ cancer-resistant immune cells inside the patient’s body. Leveraging a meticulously engineered ‘two-particle’ delivery system alongside CRISPR-Cas9 gene editing technology, the researchers inserted genetic instructions for anti-cancer CARs into specific sites within the T-cell genome, successfully generating functional CAR-T cells in vivo. In animal trials, this technology exhibited robust anti-cancer effects, achieving remarkable breakthroughs even in solid tumors, where conventional therapies have typically demonstrated limited success. Published in the esteemed journal Nature, this study represents a pivotal advancement in making cell and gene therapies more accessible and convenient, holding the promise of substantially reducing treatment costs and extending benefits to a wider patient population in the future.