Weill Cornell Medicine researchers reported that activated T cells secrete extracellular vesicles carrying DNA that can enter tumor and immune cells to enhance antigen processing and presentation. In mouse models of immunologically “cold” tumors, the DNA-containing vesicles (AT-EVs) improved antigen processing pathways in tumor cells and dendritic cells. The preclinical results showed synergy with immune checkpoint inhibitors, with the combination driving stronger antitumor effects and tumor growth suppression than either approach alone in tested models. The work was published in Cancer Cell. Investigators framed the mechanism as a potential acellular immunotherapy strategy and as a new avenue for delivering genetic payloads without relying on traditional cell-based manufacturing.