iCELLis™ 固定床生物反应器助力hMSC外泌体高效生产

Extracellular vesicles (EVs), especially smaller EVs of endosome origin, i.e. exosomes, are increasingly explored for therapeutic applications. To obtain high yields of exosomes, cell culture methods are commonly employed, especially using cell lines such as human embryonic kidney cells (HEK293) and human mesenchymal stromal cells (hMSC). HEK293 cells express exosomes via both adherent and suspension cultures, while hMSC cells express exosomes only in adherent cultures. The adherent scale-up culture methods include cell factories, fixed-bed bioreactors such as iCELLis fixed-bed bioreactor, and microcarrier suspension cultures such as Cytodex microcarriers. Suspension scale-up cultures include shake flasks, rocking bioreactors such as the ReadyToProcess WAVE 25, and stirred tank bioreactors such as the Xcellerex XDR and Xcellerex X-platform bioreactors.
Exosome purification methods include ultrafiltration concentration, density gradient centrifugation, size exclusion chromatography, and multimodal chromatography using Capto Core 400/Capto Core 700 resins. TFF technology, due to its high recovery rate and scalability, has gradually replaced traditional ultracentrifugation methods (1).
Our study explores a robust and scalable process for exosome expression from hMSC cells. In the upstream process study, we evaluate the exosome production efficiency of iCELLis Nano fixed-bed bioreactors, while in the downstream process study, we evaluate the TFF purification and characterize the functional activity of the exosomes. The goal is to establish an efficient and stable exosome production platform.