Novel Scalable Loading of Antibiotics in Exosomes for Bacterial Wound Infection Prevention

Extracellular vesicles (EVs), particularly nanosized exosomes (30-150 nm), are live cells secreted membrane vesiclesĀand natural in origin with minimal toxicity and immunogenicity to in vivo systems. Such advantages highlight the superior properties of EVs as the next-generation drug delivery and therapeutic platform. Particularly, mesenchymal stem cell secreted EVs (MSC-EVs) enable superior regenerative function for tissue/organ repairing and restoring, and reducing inflammation and fibrosis. Despite high market potential, EV preparation and cargo loading are a tremendous technical hurdle for enabling clinical translation.ĀRecent reports have shown that transfection of EVs for cargo drug loading is a key step in EV therapeutic development. However, current chemical transfection approach suffers from low transfection rate (< 25%) and low stability from produced EVs. Although electro-transfection is more efficient in terms of transfection rate (> 50%), current manufacturing is limited by scalability with only a few milliliters of processing volume in their throughput. The most high-throughput platform MaxCyte offers only cell-based cuvette electro-transfection which does not handle nanosized EVs containing more compact membrane curvatures and fragile nanostructures. In this project, we introduce a novel continuous-flow platform utilizing microfluidic droplet-based EV electro-transfection (ĄDES), which can handle EVs in large throughput and high efficiency to enable clinical translation for drug delivery and gene therapy. Droplet microfluidics have been popular in the pharma industry in recent five years for large-scale production and manufacturing of microparticles and nanoparticles, due to their scaling potential and precision control.ĀHowever, the streamlined EV electro-transfection using continuous-flow droplets as the transfection micro-reactor has not been explored elsewhere. Taking advantages of continuous-flow droplet generation, cargos can be saturated in such uniform droplet bioreactors with maximized mass transport and electro-transfection efficiency. Streamlined fast electro-transfection in milliseconds (~ms) also substantially improves throughput while using low-voltage DC power. The ĄDES is a generic platform which can be a game changer for cargo-loading and engineering MSC EVs and pushing therapeutic EV manufacturing to the next level for clinical translation.ĀIn this STTR phase I project, we will focus on the technology platform validation and exploring scalable loading of small molecule cargos into regenerative EVs, which could lay solid foundation for moving into phase II project with emphasis on the in vivo preclinical study, CMC production, and clinical trials.