Cancer immunotherapies, particularly therapeutic vaccination, do not typically generate robust anti-tumour immune responses. Here, we show that the intratumoral burst release of the protein annexin A5 from intravenously injected hollow mesoporous nanoparticles made of diselenide-bridged organosilica generates robust anti-tumour immunity by exploiting the capacity of primary tumours to act as antigen depots. Annexin A5 blocks immunosuppressive apoptosis and promotes immunostimulatory secondary necrosis by binding to the phagocytic marker phosphatidylserine on dying tumour cells. In mice bearing large established tumours, the burst release of annexin A5 owing to diselenide-bond cleavage under the oxidizing conditions of the tumour microenvironment and the reducing intracellular conditions of tumour cells induced systemic cytotoxic T-cell responses and immunological memory associated with tumour regression and the prevention of relapse, and led to complete tumour eradication in about 50% of mice with orthotopic breast tumours. Reducing apoptosis signalling via in situ vaccination could be a versatile strategy for the generation of adaptive anti-tumour immune responses.
Author Info:
(1) Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Bethesda, MD
, USA. (2) Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Bethesda, MD, USA. (3) Faculty of Health Sciences, University of Macau, Macau, P. R. China. (4) Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Bethesda, MD, USA. wenpei.fan@cpu.edu.cn. State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Center of Advanced Pharmaceuticals and Biomaterials, China Pharmaceutical University, Nanjing, P. R. China. wenpei.fan@cpu.edu.cn. (5) Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Bethesda, MD, USA. (6) Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Bethesda, MD, USA. zhen.yang3@nih.gov. (7) Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Bethesda, MD, USA. chen9647@gmail.com.
Citation: Nat Biomed Eng 2020 Aug 17 Epub08/17/2020