Leveraging cell-derived bioparticles for macromolecular delivery - 7. PROJECT SUMMARY/ABSTRACT
Many emerging therapeutic strategies employ macromolecules, like proteins or RNAs, to manipulate
intracellular contents and processes, thus mitigating disease. The success of these therapeutic strategies
requires the ability to safely and efficiently deliver macromolecules into cells within the body, which poses a
significant challenge. To overcome the biological barriers to macromolecular delivery, researchers have
developed various delivery vehicles, such as viral vectors and nanoparticles, that can package and deliver
macromolecular cargos into desired target cells. Recently, cell-derived bioparticles, including virus-like
particles and extracellular vesicles, have emerged as promising delivery vehicles that combine key benefits of
both viral- and nanoparticle-based delivery methods. However, a major challenge associated with these new
methods is their poor manufacturability, which severely limits their prospects for clinical translation.
The proposed work seeks to unlock the full potential of cell-derived bioparticles for therapeutic
macromolecule delivery by developing new strategies for highly efficient bioparticle production. Initial efforts
will focus on identifying, understanding, and manipulating genes in bioparticle producer cells that influence
bioparticle production efficiency. To determine genes that regulate bioparticle production, we will assess the
effects of thousands of different genetic perturbations on bioparticle production by performing pooled genome-
wide knockdown and activation screens in producer cells. These screens will utilize a unique design in which
sequencing a given bioparticle’s contents will identify the perturbation in the cell that produced that bioparticle.
We will perform separate screens to interrogate (1) the production of virus-like particles that package
ribonucleoprotein cargos and (2) the production of extracellular vesicles that package messenger RNA cargos,
yielding insights into two distinct types of cell-derived bioparticles and two important classes of therapeutically
relevant macromolecular cargos. These results will not only enhance our understanding of the mechanisms of
cell-derived bioparticle formation but also reveal new ways to manipulate producer cells to improve particle
production. In parallel, we will establish a new paradigm for directly transferring therapeutic bioparticles from
producer cells into target cells via cell-to-cell contact, a strategy that has the potential to substantially improve
delivery potency relative to existing methods. This investigation will lay a foundation for potentially
transformative therapeutic approaches in which patient-derived cells are engineered into bioparticle producer
cells and transplanted into the body, where they would subsequently engage desired target cells to deliver
therapeutics via locally released bioparticles. Collectively, these studies will dramatically expand the utility of
cell-derived bioparticles as delivery vehicles for macromolecular therapeutics.
