Periodic Reporting for period 1 - ProDelivery (High Throughput Synthesis of Polymeric Vesicles for Protein Delivery)
Reporting period: 2019-09-01 to 2021-08-31
The multidisciplinary nature of this highly ambitious project was strongly supported by its localisation within the world-renowned Stevens Group at Imperial College London. The diverse nature of the project required input from a number of personnel within the Group with research backgrounds across chemistry, materials science, spectroscopy and cell biology and was crucial to meeting project outcomes. Ongoing collaborations which have been established as a result of this fellowship will continue to drive this work towards future applications.
1. A novel strategy to downscale polymersome synthesis to the microlitre scale was optimised and developed. This overcomes some limitations of traditional polymersome forming strategies such as thin film rehydration which typically requires millilitre scale volumes. As a result, when loading proteins into the lumen of polymersomes, significantly lower quantities of expensive proteins are required and higher therapeutic loadings become economically feasible. We have also developed a range a complementary tools to characterise enzyme loaded polymersomes based on single-particle fluorescence and Raman spectroscopic techniques.
2. When loading a luminescence enzyme as a model protein therapeutic to form enzyme-loaded polymersomes, we have demonstrated significantly enhanced enzymatic resistance to physical and chemical stresses. This demonstrates the importance of nanoformulation of protein therapeutics in enhancing not only in vivo half-life (and hence, potency) but, also in improving the overall shelf-life and reducing the economic impact of cold-chain transportation for drug delivery applications.
3. We’ve demonstrated that optimised polymersome formulations loaded with model enzymes have no detectable cytotoxicity across a range of concentrations and can be efficiently taken up into a model cell line. Further, the enzymatic activity inside uptaken polymersomes can be retained for at least a week in culture demonstrating the excellent stability of the nanoformulation. These optimised polymersomes show excellent promise for the delivery of therapeutic enzymes whereby the mode of action is primarily catalytic.
4. For the release of protein-based payloads, we have also developed mechanisms to release encapsulated protein therapeutics. For example, we have developed polymersome formulations that can be disassembled in response to lowered pH conditions such as those commonly encountered in diseased tissue microenvironments. This disassembly of the nanoparticle results in release of the encapsulated therapeutics. We are currently exploring suitable in vitro models to continue this work beyond the end of this Marie Curie fellowship.
The key concepts from this fellowship were presented at the Recent Appointees in Polymer Science (RAPS) conference in Leeds with a larger overview of the project to be presented at the upcoming ACS Spring 2022 meeting. Two publications are currently under preparation for submission to high impact publications which will report the crucial findings of this project. These publications will acknowledge all European Commission funding and will comply with EU open access policies. I have also participated in broader outreach activities such as Imperial College’s Great Exhibition Road Festival, to disseminate my research findings and general research interests to the general public. Although significant disruption to planned dissemination activities was incurred due to the COVID-19 pandemic, these will be greatly pursued as further opportunities become more available. Finally, the fundamental knowledge gained from this work has facilitated the training and project development of several research students and will result in further outcomes from this fellowship.