Abstract

Extracellular vesicles (EVs) are a promising drug delivery platform as they compartmentalize bioactive payloads prior to delivery, have low immunogenicity, and are capable of tissue-specific targeting. EV-based therapeutics in most research pipelines are produced using cultured human mesenchymal stem cells. This approach is limiting as they are not amenable to complex genetic engineering, are expensive to grow and maintain, produce heterogenous EVs that are challenging to purify, and cannot be easily upscaled. Baker’s yeast (Saccharomyces cerevisiae) is an excellent candidate for EV research, as it exhibits similar fundamental EV biology and may overcome these and other limitations. Using S. cerevisiae as a model, this study aims to determine if yeast strains expressing EV localization peptides can produce engineered EVs loaded with bioactive cargo. To achieve this, a panel of genetically modified yeast strains was generated to express fluorescently tagged versions of known EV markers and bioproduction was quantified with single particle analyses.