Efficient manufacturing of therapeutic mesenchymal stromal cells with the use of the Quantum Cell Expansion System

Background: The use of bone marrow-derived mesenchymal stromal cells (MSCs) as a cellular therapy for various diseases, such as graft-versus-host disease, diabetes, ischemic cardiomyopathy and Crohn's disease, has produced promising results in early-phase clinical trials. However, for widespread application and use in later phase studies, manufacture of these cells must be cost-effective, safe and reproducible. Current methods of manufacturing in flasks or cell factories are labor-intensive, involve a large number of open procedures and require prolonged culture times. Methods: We evaluated the Quantum Cell Expansion System for the expansion of large numbers of MSCs from unprocessed bone marrow in a functionally closed system and compared the results with a flask-based method currently in clinical trials. Results: After only two passages, we were able to expand a mean of 6.6× 10⁸ MSCs from 25 mL of bone marrow reproducibly. The mean expansion time was 21 days, and cells obtained were able to differentiate into all three lineages: chondrocytes, osteoblasts and adipocytes. The Quantum was able to generate the target cell number of 2.0× 10⁸ cells in an average of 9 fewer days and in half the number of passages required during flask-based expansion. We estimated that the Quantum would involve 133 open procedures versus 54,400 in flasks when manufacturing for a clinical trial. Quantum-expanded MSCs infused into an ischemic stroke rat model were therapeutically active. Conclusions: The Quantum is a novel method of generating high numbers of MSCs in less time and at lower passages when compared with flasks. In the Quantum, the risk of contamination is substantially reduced because of the substantial decrease in open procedures.