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Updated: Jul 1, 2026
Near Infrared Photoimmunotherapy for Mouse Models of Pleural Dissemination
Published on: February 9, 2021
Utilizing Rationally Designed Photosensitizers to Drive Divergent Immunogenic Cell Death in Photoimmunotherapy
Jia Huang1, Zhiqiang Wang2, Heng Li2
1Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, P. R. China.
Abstract:
Photodynamic therapy (PDT)-based photoimmunotherapy represents a promising modality for cancer treatment, combining the precision of PDT with the sustained efficacy of immunotherapy. A key innovation in this field involves the use of organic photosensitizers to induce immunogenic pyroptosis. However, the fundamental question of whether type I and type II PDT elicit equally potent immune responses remains unresolved. To address this, we developed a series of A-D-A structured organic photosensitizers via rational donor-acceptor engineering. This molecular strategy enables precise control over the photodynamic pathway by fine-tuning the intramolecular charge transfer strength, thereby establishing a platform for systematically comparing their immunogenic potential. Our mechanistic investigations reveal a critical distinction: type I-dominant photosensitizers are more effective than their type II-dominant counterparts at triggering caspase-1-mediated pyroptosis. This pyroptotic cascade stimulates the release of damage-associated molecular patterns and pro-inflammatory factors, culminating in potent immune activation. As a result, the leading type I photosensitizer is more capable of inducing a systemic antitumor immune response and suppressing distant tumors under a low-power 808 nm photoirradiation. Overall, this work not only decouples the immunogenic roles of type I and type II photodynamics but also provides a rational design strategy for advanced photoimmunotherapy agents.
Insights
Type I photodynamic therapy (PDT) photoimmunotherapy is more effective than type II for triggering pyroptosis and activating anti-tumor immunity. This research offers a new design strategy for advanced cancer treatments.
Area of Science:
- Oncology
- Immunology
- Materials Science
Background:
- Photoimmunotherapy combines photodynamic therapy (PDT) and immunotherapy for cancer treatment.
- Organic photosensitizers can induce immunogenic pyroptosis, enhancing anti-tumor immune responses.
- The relative immunogenic potential of type I and type II PDT pathways is not well understood.
Purpose of the Study:
- To systematically compare the immunogenic potential of type I and type II photodynamic therapy.
- To develop a rational design strategy for organic photosensitizers for photoimmunotherapy.
Main Methods:
- Engineered A-D-A structured organic photosensitizers with tunable intramolecular charge transfer.
- Investigated photodynamic pathways (Type I vs. Type II) and their effect on pyroptosis induction.
- Assessed immune activation, systemic anti-tumor response, and distant tumor suppression.
Main Results:
- Type I-dominant photosensitizers more effectively trigger caspase-1-mediated pyroptosis compared to type II-dominant ones.
- Pyroptosis induced by type I PDT releases damage-associated molecular patterns and pro-inflammatory factors, activating the immune system.
- The lead type I photosensitizer demonstrated significant systemic anti-tumor immunity and suppressed distant tumors under low-power near-infrared irradiation.
Conclusions:
- Type I and Type II photodynamics have distinct roles in immune response activation.
- Type I-dominant photosensitizers are superior for inducing pyroptosis and potent anti-tumor immunity in photoimmunotherapy.
- This study provides a rational design framework for developing next-generation photoimmunotherapy agents.
