In an article published in Plos One (August 25 2017) UCL researchers gave the first example of a large volume biomass being successfully cryopreserved in a single cassette and re-cultured. It demonstrates that a bioartificial liver device can be cryopreserved, and has wider applications to scale-up large volume cryopreservation.
The study optimised parameters such as excess media concentration and warming rates and used the findings to enable the successful cryopreservation of 2.3 litres of alginate encapsulated liver cell spheroids. The study of large volume cryopreservation is also essential to improve transplant results. Currently organs can only be preserved in a chilled state (typically between 0–4°C) for a maximum of between 4–24 h, depending on the organ. This greatly inhibits successful transplant numbers and outcomes.
The focus in cryopreservation of cells has largely been on small volumes, typically up to 1 ml samples. Exceptions are the cryopreservation of adult stem cells and T-cell therapies, typically in volumes 50-500ml, and ELS and other cell types in cryobags. There have been reports of successful cryopreservation of sheep ovaries and the vitrification of a rabbit kidney but no record of biomasses larger than 500ml cryobags (for cell suspensions), or volumes larger than a few hundred ml for more complex biomasses being cryopreserved in the frozen state.
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Find full article at Plos One