Enhancing cryopreservation of human iPSCs: Bottom-up vs Conventional freezing geometry

Teodoro, F.; El-Guendouz, S.; Neves, R.; Duarte, A.; Rodrigues, M. A.; Melo, E. P.

doi:10.1101/2024.10.30.621091

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bioRxiv · 10.1101/2024.10.30.621091

Enhancing cryopreservation of human iPSCs: Bottom-up vs Conventional freezing geometry

Teodoro, F.·El-Guendouz, S.·Neves, R.·Duarte, A.·Rodrigues, M. A.·Melo, E. P.

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Abstract

Induced pluripotent stem cells (iPSCs) hold large potential on regenerative medicine due to their pluripotency and unlimited self-renewal capacity without the ethical issues of embryonic stem cells. To provide quality-controlled iPSCs for clinical therapies, it is essential to develop safe cryopreservation protocols for long-term storage, preferable amenable for scale-up and automation. We have compared the impact of two different freezing geometries (bottom-up and conventional radial freezing) on the viability and differentiation capability of human iPSCs. Our results demonstrate that the bottom-up freezing under optimized conditions significantly increases iPSCs viability, up to 9% for the cell membrane integrity and up to 21% for the cell metabolic state, compared to conventional freezing. The improvement achieved for bottom-up versus conventional freezing was maintained after scale-up from cryogenic vials to 30 mL bags, highlighting the methods potential for clinical applications. These findings show that bottom-up freezing can offer a more controlled and scalable cryopreservation strategy for iPSCs, promoting their future use in regenerative medicine.

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Teodoro, F., El-Guendouz, S., Neves, R., Duarte, A., Rodrigues, M. A., Melo, E. P.. 2024-11-03. Enhancing cryopreservation of human iPSCs: Bottom-up vs Conventional freezing geometry. https://doi.org/10.1101/2024.10.30.621091

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