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Paramyxoviruses for Tumor-targeted Immunomodulation: Design and Evaluation Ex Vivo
Published on: January 7, 2019
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Engineered Bacterial Outer Membrane Vesicles Remodel Tumor Microenvironment for Enhanced Photodynamic Immunotherapy
Chaofan Nie1, Peiren Wang1, Junru Wang1
1State Key Laboratory of Flexible Electronics (LoFE), Xi'an Institute of Flexible Electronics, and Xi'an Institute of Biomedical Materials and Engineering, Northwestern Polytechnical University, Xi'an, China.
Advanced Healthcare Materials
|December 26, 2025
Summary
Engineered nanotherapeutics (PN@OMVs) overcome tumor microenvironment (TME) suppression by combining photodynamic therapy and IDO1 inhibition. This approach significantly boosts antitumor immunity and achieves high tumor inhibition rates with minimal toxicity.
Area of Science:
- Biomedical Engineering
- Immunology
- Nanotechnology
Background:
- Tumor immunotherapy faces challenges from the immunosuppressive tumor microenvironment (TME), leading to treatment resistance.
- Existing TME-modulating agents often exhibit poor solubility and systemic toxicity.
- Outer membrane vesicles (OMVs) offer a potential platform for drug delivery but require engineering for enhanced therapeutic effects.
Purpose of the Study:
- To develop an engineered nanotherapeutic platform (PN@OMVs) for overcoming TME-mediated immunosuppression.
- To investigate the synergistic effects of photodynamic therapy (PDT) and indoleamine 2,3-dioxygenase 1 (IDO1) inhibition within OMVs.
- To evaluate the efficacy and safety of PN@OMVs in a preclinical cancer model.
Main Methods:
- Engineered OMVs by co-encapsulating pheophorbide a (PPa) and the IDO1 inhibitor NLG919.
- Utilized Escherichia coli BL21-derived OMVs for PN@OMVs construction.
- Assessed PN@OMVs efficacy in a murine bilateral subcutaneous CT26 colon cancer model, including immune cell analysis and tumor growth evaluation.
Main Results:
- PN@OMVs significantly enhanced systemic antitumor immunity, evidenced by increased dendritic cell maturation (2.77% to 19.84%).
- PN@OMVs effectively inhibited IDO1 activity, disrupted the tryptophan-kynurenine pathway, and reduced regulatory T cell infiltration, reversing TME immunosuppression.
- A single PN@OMVs administration with light irradiation achieved 92.3% primary and 83.1% distant tumor inhibition rates without observable systemic toxicity.
Conclusions:
- Engineered OMVs (PN@OMVs) represent a promising platform for synergistic cancer immunotherapy.
- PN@OMVs effectively remodel the immunosuppressive TME, enhancing antitumor immune responses.
- This nanotherapeutic strategy offers a potential solution for improving immunotherapy efficacy and reducing treatment-related toxicity.
Keywords:
colorectal cancerimmunotherapyouter membrane vesiclesphotodynamic therapyremodeling tumor microenvironmentMore Related Videos
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