Delineation of optimal culture conditions for the production of therapeutic human mesenchymal stromal cell-derived extracellular vesicles (MSC-EVs) in static cultures

Diogo Jorge Estrela

Key information

Authors:

Diogo Jorge Estrela (Diogo Jorge Estrela)

Supervisors:

Ana Margarida Pires Fernandes Platzgummer (Ana Margarida Pires Fernandes Platzgummer); Raquel Medina dos Santos Cunha (Raquel Medina dos Santos Cunha)

Published in

December 7, 2021

Abstract

Mesenchymal stromal cells (MSCs) have been studied for therapeutic applications due to their promising properties. In the last years, MSC therapeutic effects have been associated to the release of extracellular vesicles (EVs) as paracrine signaling. MSC-EVs therapeutic potential has already been reported as beneficial for different diseases and seem to recapitulate the therapeutic effects of MSCs, creating expectations to a promising, safe, and effective cell-free-based therapy. However, a considerable amount of EVs is needed for therapeutic applications and thus, cell culture processes need optimization to ensure high productivity, combined with quality, consistency, reproducibility, and safety. In this manner, this project involves the study of different cell culture parameters (MSC source, time points for culture medium exchange and EV collection, temperature and oxygen concentration) to obtain an optimized human MSC EVs-based product. Overall, the MSC source and the medium exchange seemed not to imply significant variability in EV productivity, and the time point after MSC expansion and medium conditioning seemed the best one for EV collection. Regarding the removal of culture medium particles that could have contaminated the MSC-EV samples, a filtration with 0.1 µm filter seemed inefficient. The temperature of 33ºC applied during conditioning medium seemed to increase the EV productivity, contrarily to hypoxia, but further studies are necessary. In sum, besides the necessary further studies, the present work provides insights regarding the influence of different cell culture parameters in MSC-EV production that can contribute to reach in the future the best quality/potency and productivity of MSC EV-based products.