Scaling up mesenchymal stromal cell extracellular vesicle production for therapeutic application in rheumatoid arthritis

Davies, Rebecca Louise

Abstract

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disease. Given the complexity of RA and current treatment limitations, mesenchymal stromal cell extracellular vesicles (MSC EVs) have been proposed as an alternative. These small membrane-bound particles contain MSC derived biological cargo capable of immunomodulation and the ability to ameliorate disease in murine RA models. Compared to cell therapies, EVs reduce safety concerns, are easily stored, and better permeate tissue. However, EV production suffers from low yields and must be scaled without compromising therapeutic potential.

Methods: To scale EV production, we used a pooled donor and Quantum™ bioreactor strategy. Single and pooled MSC EVs were characterised, compared, and used to treat an antigen-induced arthritis (AIA) model, along with their parental MSCs. The same occurred for Quantum™ and tissue culture plastic (TCP) EVs which were used to treat RA patient’s peripheral blood mononuclear cells (PBMCs), along with MSCs.

Results: Pooled MSC EV enrichments contained more particles than single donors. Both had typical EV characteristics, yet pooled EVs displayed a distinct proteomic profile, encouraging an increase in transport mechanisms. In the AIA mouse model, pooled EVs surpassed MSCs, and single donor EVs, in alleviating RA pathophysiology but did not alter T-cell subsets. Quantum™ EVs matched the particle concentrations of TCP but displayed a higher proportion of EV and MSC markers. In culture with RA patients’ PBMCs, EV therapeutic potential was present, but variable, and did not match the capabilities of MSCs.

Conclusion: Donor pooling is a simple method to enhance MSC EV production, although scaling using the Quantum™ requires further work. Both demonstrated a potential to be therapeutically beneficial to an AIA model and RA patient PBMCs respectively. Specifically, MSC EVs for clinical use in localised injections could manage disease progression or offer relief during rheumatic flares.

Citation

Davies, R. L. (2025). Scaling up mesenchymal stromal cell extracellular vesicle production for therapeutic application in rheumatoid arthritis. (Thesis). Keele University. https://keele-repository.worktribe.com/output/1280129

• Thesis Type: Thesis
• Online Publication Date: Jun 26, 2025
• Deposit Date: Jun 18, 2025
• Public URL: https://keele-repository.worktribe.com/output/1280129
• Additional Information: Embargo on access until 2 September 2025 - The thesis is due for publication, or the author is actively seeking to publish this material.
• Award Date: 2025-06