Weill Cornell Medicine researchers reported preclinical evidence that activated T cells secrete extracellular vesicles containing DNA that can enter tumor and immune cells to stimulate antigen processing and presentation. The study described activated T cell-derived EVs improving antigen processing across immunologically cold tumors in mice. The work also reported synergy with immune checkpoint inhibitors, with results showing tumor growth suppression when AT EVs were combined with checkpoint blockade. The investigators described the vesicle-associated DNA as a potential acellular immunotherapy strategy and a possible genetic payload-delivery approach. The findings were published in Cancer Cell and frame a new mechanism for enhancing immune visibility in tumors that otherwise fail to trigger robust responses.