21ENGBIO PROJECT ECHO: Modular exosome prototyping & engineering

Our cells produce and secrete nanosized extracellular vesicles, called exosomes - which are essentially molecular messages that cells send to each other. These exosomes are composed of many different molecular components, including proteins and other molecules, that are encased in a lipid (fat) bilayer. Exosomes have many different roles in the body and can help keep us healthy. Ongoing research has also shown that exosomes could potentially be used as therapies to treat diseases including cancers. Unfortunately, exosomes, are highly complex and it is often challenging to engineer lab grown cells to make new types of therapeutic exosomes. To help address these challenges we will develop new cell-free methods for engineering exosomes outside of the cell - potentially making it quicker and easier to develop new therapeutic exosomes. These cell-free methods will also be combined with liquid handling robotics so that we can more easily engineer lots of different exosomes in parallel. If successful, we envision that our project could enable us to collaborate with pharmaceutical companies to accelerate this promising new therapeutic class.

Exosomes, and other types of extracellular vesicles (EVs), are rapidly emerging as a promising class of nanovesicle therapeutics and drug delivery vehicles across oncology, CNS disorders, inflammatory and other diseases. Exosomes are complex and engineering cells to produce exosomes with defined therapeutic modalities is challenging. Likewise, limitations in widely-used exosome isolation methods are also hampering the scale-up and manufacturing of exosome therapeutics. To help address these exosome engineering challenges we propose an engineering biology breakthrough award project in which we will develop and automate cell-free-based exosome engineering workflows. Cell-free gene expression (CFE) systems enable in vitro protein production, including membrane proteins, and are emerging as versatile prototyping and biomanufacturing platforms for biological materials and biologics. Beneficially, cell-free reaction workflows can typically be carried out in much shorter timeframes than cell-based workflows, are automatable and do not suffer from some of the limitations of typical cell culture (e.g. poor plasmid transfection efficiencies). We envision that, if successful, these data and capabilities will provide a powerful platform for future innovations in cell-free exosome engineering that we and our future collaborators could utilise to test novel therapeutic exosome designs.