Iridium complex-loaded biomimetic vesicles enable enhanced photodynamic therapy and immune modulation

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Cancer Therapy

Background:

• Solid tumor therapy requires advanced strategies combining micro/nano-engineering with optical responses.
• Current therapies face challenges in biocompatibility, targeting efficiency, and synergistic therapeutic effects.

Purpose of the Study:

• To develop a biomimetic nanosystem for enhanced solid tumor therapy.
• To leverage giant plasma membrane vesicles (GPMVs) for targeted delivery and biocompatibility.
• To investigate the synergistic effects of photodynamic therapy and immune stimulation.

Main Methods:

• Encapsulation of a flexible-chain iridium complex (IrC8) within tumor-derived GPMVs.
• Evaluation of cellular uptake, optical properties, and reactive oxygen species (ROS) generation.
• Assessment of phototoxicity, immunogenic cell death (ICD) induction, and overall therapeutic efficacy in solid tumors.

Main Results:

• The GPMV-encapsulated IrC8 system showed a 4.7% increase in cellular uptake compared to the free complex.
• The nanosystem exhibited strong optical properties (aggregation-induced emission enhancement factor > 10) and a high singlet-oxygen quantum yield (ΦΔ = 0.18).
• Photoactivation led to an 18-fold increase in ROS yield, causing over 90% tumor cell apoptosis and triggering ICD for immune activation.

Conclusions:

• The biomimetic nanosystem effectively enhances homologous targeting and biocompatibility for solid tumor treatment.
• The integrated system provides potent photodynamic therapy and stimulates an anti-tumor immune response.
• This synergistic approach demonstrates significant therapeutic potential against solid tumors.