Unlocking Intracellular Protein Delivery by Harnessing Polymersomes Synthesized at Microliter Volumes using...

Area of Science:

• Nanomedicine
• Biomedical Engineering
• Polymer Chemistry

Background:

• Intracellular delivery of therapeutic proteins and vaccine antigens is hindered by poor cell membrane permeation and endolysosomal degradation.
• Developing efficient delivery systems is crucial for advancing subunit vaccines and cancer immunotherapies.

Purpose of the Study:

• To develop an oxygen-tolerant photoinitiated polymerization-induced self-assembly (Photo-PISA) process for efficient intracellular delivery.
• To enable high-throughput screening of therapeutic proteins and vaccine antigens using ultralow volumes.

Main Methods:

• Microliter-scale (10 µL) synthesis of protein-loaded polymersomes in 1536-well plates using Photo-PISA.
• High-resolution techniques including confocal microscopy and stochastic optical reconstruction microscopy (STORM) for particle analysis and visualization.
• Encapsulation and delivery of a prototype vaccine antigen to assess cellular activation and antigen cross-presentation.

Main Results:

• Successful synthesis of protein-loaded polymersomes via an oxygen-tolerant Photo-PISA process.
• Visualization of efficient protein delivery into the cytosol with subsequent endosomal escape.
• Demonstration of vaccine antigen delivery, leading to antigen-presenting cell activation and cross-presentation.

Conclusions:

• The Photo-PISA platform facilitates efficient intracellular delivery of proteins and antigens with ultralow volume synthesis.
• This approach significantly enhances the screening of therapeutic proteins and vaccine candidates for nanomedicine and cancer immunotherapy.
• The developed polymersomes show promise for advancing subunit vaccines and intracellular drug delivery applications.