A roadmap towards manufacturing extracellular vesicles for cardiac repair.

Despite the heterogeneity associated with extracellular vesicle (EV) biogenesis pathways and the physiological state of the EV parental cells, standardization of EV manufacturing workflows could contribute to increase intra- and inter-batch reproducibility. Reaching effective EV doses for clinical use in cardiac regenerative settings requires large-scale platforms for EV production and isolation and/or strategies that maximize EV secretion per cell. While bioreactors – such as stirred-tank or vertical-wheel bioreactors – are envisioned as scalable platforms to sustain cell secretion of EVs, membrane-based processes can allow continuous and large-scale isolation of EVs. Both single-vesicle analysis and omics approaches can be relevant tools to dissect the mechanism of action of EVs in cardiac repair. For the past two decades researchers have linked extracellular vesicle (EV)-mediated mechanisms to various physiological and pathological processes in the heart, such as immune response regulation, fibrosis, angiogenesis, and the survival and growth of cardiomyocytes. Although use of EVs has gathered momentum in the cardiac field, several obstacles in both upstream and downstream processes during EV manufacture need to be addressed before clinical success can be achieved. Low EV yields obtained in small-scale cultures deter clinical translation, as mass production is a prerequisite to meet therapeutic doses. Moreover, standardizing EV manufacture is critical given the inherent heterogeneity of EVs and the constraints of current isolation techniques. In this review, we discuss the critical steps for the large-scale manufacturing of high-potency EVs for cardiac therapies. [ABSTRACT FROM AUTHOR]