Cryopreservation of Organoids

Organoids represent indispensable opportunities for biomedicine, including drug discovery, cancer biology, regenerative and personalised medicine or tissue and organ transplantation. However, the lack of optimised preservation strategies limits the wide use of organoids in research or clinical fields. In this review, we present a short outline of the recent developments in organoid research and current cryopreservation strategies for organoid systems. While both vitrification and slow controlled freezing have been utilized for the cryopreservation of organoid structures or their precursor components, the controlled-rate slow freezing under protection of Me2SO remains the most common approach. The application of appropriate pre- or post-treatment strategies, like the addition of Rho-kinase or myosin inhibitors into cell culture or cryopreservation medium, can increase the recovery of complex organoid constructs post-thaw. However, the high complexity of the organoid structure and heterogeneity of cellular composition bring challenges associated with cryoprotectant distribution, distinct response of cells to the solution and freezing-induced injuries. The deficit of adequate quality control methods, which may ensure the assessment of organoid recovery in due term without prolonged re-cultivation process, represents another challenge limiting the reproducibility of current cryobanking technology. In this review, we attempt to assess the current demands and achievements in organoid cryopreservation and highlight the key questions to focus on during the development of organoid preservation technologies.