Proof-of-Concept of a Novel Cell Separation Technology Using Magnetic Agarose-Based Beads

Abstract

The safety of the cells used for Advanced Therapy Medicinal Products is crucial for patients. Reliable methods for the cell purification are very important for the commercialization of those new therapies. With the large production scale envisioned for commercialization, the cell isolation methods need to be efficient, robust, operationally simple and generic while ensuring cell biological functionality and safety. In this study, we used high magnetized magnetic agarose-based beads conjugated with protein A to develop a new method for cell separation. A high separation efficiency of 91% yield and consistent isolation performances were demonstrated using population mixtures of human mesenchymal stem cells and HER2+ SKBR3 cells (80:20, 70:30 and 30:70). Additionally, high robustness against mechanical stress and minimal unspecific binding obtained with the protein A base conjugated magnetic beads were significant advantages in comparison with the same magnetic microparticles where the antibodies were covalently conjugated. This study provided insights on features of large high magnetized microparticles, which is promising for the large-scale application of cell purification.

Direct Affinity Ligand Immobilization onto Bare Iron Oxide Nanoparticles Enables Efficient Magnetic Separation of Antibodies

“…We consider magnetic separation a highly promising alternative, which has found increasing popularity in recent years. − ,− This technique is based on nonporous magnetic particles that are freely dispersed in the process fluid and can be controlled magnetically. The nonporous magnetic particle adsorbent leads to reduced mass transfer limitations compared to conventional porous chromatography beds, which favors fast target adsorption/desorption and, thus, high throughput. , Furthermore, clogging of the purification matrix is prevented due to the nonporosity, enabling the direct processing of unclarified cell culture broth and process intensification. , Another powerful characteristic of the technique is the scale-independence of the magnetic adsorption process, which simplifies the scale-up …”

“… 16 , 19 Another powerful characteristic of the technique is the scale-independence of the magnetic adsorption process, which simplifies the scale-up. 27 …”