A COMPARABILITY STUDY OF CHROMATOGRAPHY RESINS SUITABLE FOR EV PURIFICATION FROM A HIGHLY PRODUCTIVE MSC BIOPROCESSING PLATFORM

• Published in: Cytotherapy (Oxford, England) Vol. 26; no. 6; p. S87
• Main Authors: Jung, J., Lenzini, S., Budiman, M., Rowley, J.A., Zakhem, E.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01-06-2024
• Subjects: chromatography; potency; purification; potency; purification; chromatography
• ISSN: 1465-3249; 1477-2566
• DOI: 10.1016/j.jcyt.2024.03.163

Background & Aim: The number of clinical trials investigating extracellular vesicles (EVs) derived from mesenchymal stromal cells (MSCs) as a therapeutic agent has rapidly increased in recent years. However, methods to purify the EVs are still considered as one of the main challenges during processing. The goal of this study was to evaluate EV yield and purity using different chromatography resins for EV purification.
Human MSC-EV conditioned media was produced in a bioreactor using RoosterCollect™-EV medium as described previously. The media was harvested, clarified and concentrated through TFF. Concentrated media was then split into aliquots which were used to load onto different chromatography resins (CaptoCore 400 and SuperSEC EV columns). Pre-column pressures, EV recovery and Purity (measured as particles/mg of protein) were assessed. EV Critical Quality Attributes (CQAs) were measured at the end of the process to confirm EV purity, identity and bioactivity.
9.1E9 EVs/ml were generated using xeno-free (XF)-RoosterVial-hBM MSCs, RoosterNourish-MSC-XF expansion media and RoosterCollect-EV medium. Two chromatography modalities were evaluated; a commercially available resin (multimodal ligands with size-exclusion – Capto Core 400) and an EV-specific size exclusion-based resin (SuperSEC). There was minimal pre-column pressure rise during the process, indicating adequate loading of the columns and their compatibility with the feed. Both resins achieved high EV recovery (97% recovery with Capto Core 400 vs. 89% recovery with SuperSEC). Both columns achieved high protein impurity clearance, leading to increase in purity level compared to harvest. At harvest, purity was at 9E+10 particles/mg of protein. Capto Core 400 increased purity to 6E+11 particles/mg protein while SuperSEC increased purity to 1.4E+12 particles/mg protein. EVs generated in this process maintained critical quality attributes of EV identity (expression of EV specific tetraspanins CD63, CD9 and CD81).
In this work, we generated a high concentration of clinically relevant EVs and compared two chromatography resins for EV purification. Both resins showed similar high EV recovery and increase in purity, indicating that most of the impurities were cleared through those resins. Both resins showed promising results as purification platforms for EV application.