Hu and Liu et al. found that activated T cells secreted abundant extracellular vesicular DNA (AT-EVDNA) that was mainly from newly made genomic DNA and was rich in immune-related genes. Upon uptake of EVs by tumor cells or dendritic cells, granzyme B encapsulated in the EVs disrupted the nuclear envelope and facilitated entry of EVDNA into the nucleus, where transient expression of the EVDNA increased antigen processing and presentation machinery and cytokine production, enhancing immunogenicity. In mouse models, AT-EVs overcame immune evasion and boosted immune checkpoint blockade, supporting their potential use as an acellular immunotherapy.

Contributed by Lauren Hitchings

ABSTRACT: Antigen processing and presentation (APP) is essential for adaptive immunosurveillance. We uncover a mechanism whereby activated T cell-derived extracellular vesicles (AT(EVs)) drive a positive feedback loop that enhances antigen presentation and immune responses in normal physiology and cancer. AT(EV)-induced immunogenicity relies on extracellular vesicular double-stranded DNA (EV(DNA)), which is notably abundant and primarily composed of genomic DNA enriched in immune-related genes, including those encoding APP machinery. Mechanistically, granzyme B (Gzmb) packaged by AT(EVs) disrupts the nuclear envelope of recipient cells, facilitating intranuclear transfer and subsequent transient expression of EV(DNA) encoding APP genes. DNase treatment removes most AT-EV(DNA), abrogating APP upregulation and thus T cell activation and recruitment to tumors. Notably, AT(EVs) hold promise as an acellular immunotherapy, restoring APP and synergizing with checkpoint blockade in immunotherapy-refractory tumors. Collectively, our findings uncover a mechanism of transient, non-viral gene delivery by AT(EVs) that boosts APP and anti-tumor immunity while limiting autoimmunity.

Author Info: (1) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center , Weill Cornell Medicine, New York, NY, USA; Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, USA. (2) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. (3) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. (4) Department of Physiology, Biophysics, and Systems Biology, Weill Cornell Medicine, New York, NY, USA. (5) Department of Physiology, Biophysics, and Systems Biology, Weill Cornell Medicine, New York, NY, USA. (6) Department of Physiology, Biophysics, and Systems Biology, Weill Cornell Medicine, New York, NY, USA. (7) Department of Systems Biology, Columbia University, New York, NY, USA. (8) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. (9) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA; Thoracic Surgery Service, Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, NY, USA; Department of Respiratory Medicine, Juntendo University, Tokyo, Japan. (10) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA; Department of Biomedical and Clinical Sciences, Linkšping University, Linkšping, Sweden. (11) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. (12) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. (13) Drukier Institute for Children's Health and Department of Pediatrics, Weill Cornell Medicine, New York, NY, USA. (14) Drukier Institute for Children's Health and Department of Pediatrics, Weill Cornell Medicine, New York, NY, USA. (15) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. (16) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. (17) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. (18) Drukier Institute for Children's Health and Department of Pediatrics, Weill Cornell Medicine, New York, NY, USA. (19) Drukier Institute for Children's Health and Department of Pediatrics, Weill Cornell Medicine, New York, NY, USA. (20) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. (21) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. (22) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. (23) Department of Molecular Cell Biology, The Weizmann Institute of Science, Rehovot, Israel. (24) Proteomics Resource Center, The Rockefeller University, New York, NY 10065, USA. (25) Hepatopancreatobiliary Service, Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, NY, USA. (26) Department of Molecular Cell Biology, The Weizmann Institute of Science, Rehovot, Israel. (27) Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. (28) Department of Pathology, University of California, San Diego, La Jolla, CA, USA. (29) Laboratory of Tumor Microenvironment and Therapeutic Resistance, KU Leuven, Leuven, Belgium. (30) Laboratory of Biology of Tumor and Development, UniversitŽ de Lige, Lige, Belgium. (31) Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE, USA. (32) Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE, USA. (33) Cancer Center, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, NY 11724, USA. (34) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. (35) Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA. (36) Gastrointestinal Oncology Service, Memorial Sloan Kettering Cancer Center, New York, NY, USA. (37) Thoracic Surgery Service, Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, NY, USA. (38) Department of Radiation Oncology, Weill Cornell School of Medicine, New York, NY, USA. (39) Drukier Institute for Children's Health and Department of Pediatrics, Weill Cornell Medicine, New York, NY, USA. (40) Drukier Institute for Children's Health and Department of Pediatrics, Weill Cornell Medicine, New York, NY, USA. (41) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA; Yonsei Cancer Center, Division of Medical Oncology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, South Korea. (42) Department of Physiology, Biophysics, and Systems Biology, Weill Cornell Medicine, New York, NY, USA. (43) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. Electronic address: haz2005@med.cornell.edu. (44) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. Electronic address: irm2224@med.cornell.edu. (45) Children's Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children's Health, Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA. Electronic address: dcl2001@med.cornell.edu.