Pancreatic islet cryopreservation by vitrification achieves high viability, function, recovery and clinical scalability for transplantation

Abstract

Pancreatic islet transplantation can cure diabetes but requires accessible, high-quality islets in sufficient quantities. Cryopreservation could solve islet supply chain challenges by enabling quality-controlled banking and pooling of donor islets. Unfortunately, cryopreservation has not succeeded in this objective, as it must simultaneously provide high recovery, viability, function and scalability. Here, we achieve this goal in mouse, porcine, human and human stem cell (SC)-derived beta cell (SC-beta) islets by comprehensive optimization of cryoprotectant agent (CPA) composition, CPA loading and unloading conditions and methods for vitrification and rewarming (VR). Post-VR islet viability, relative to control, was 90.5% for mouse, 92.1% for SC-beta, 87.2% for porcine and 87.4% for human islets, and it remained unchanged for at least 9 months of cryogenic storage. VR islets had normal macroscopic, microscopic, and ultrastructural morphology. Mitochondrial membrane potential and adenosine triphosphate (ATP) levels were slightly reduced, but all other measures of cellular respiration, including oxygen consumption rate (OCR) to produce ATP, were unchanged. VR islets had normal glucose-stimulated insulin secretion (GSIS) function in vitro and in vivo. Porcine and SC-beta islets made insulin in xenotransplant models, and mouse islets tested in a marginal mass syngeneic transplant model cured diabetes in 92% of recipients within 24–48 h after transplant. Excellent glycemic control was seen for 150 days. Finally, our approach processed 2,500 islets with >95% islets recovery at >89% post-thaw viability and can readily be scaled up for higher throughput. These results suggest that cryopreservation can now be used to supply needed islets for improved transplantation outcomes that cure diabetes.

Small-molecule fulvic acid with strong hydration ability for non-vitreous cellular cryopreservation

“…For instance, antifreeze proteins (AFPs) can efficiently protect many overwintering organisms from freezing damage by inhibiting ice growth/recrystallization ( Bar Dolev et al., 2016 ). Compared with the cryopreservation method of vitrification, which needs large amounts of toxic permeable cryoprotectants such as glycerol or dimethyl sulfoxide, as well as fast cooling rates to promote water forming amorphous glass (ice-free) state ( Fahy and Wowk, 2021 ; Zhan et al., 2022 ), AFP-inspired ice-control strategy is superior in terms of biocompatibility and mass cryopreservation ( Deller et al., 2014 ; Fowler and Toner, 2006 ). However, despite the excellent ice growth/recrystallization inhibition activity of AFPs, their practical applications in cryopreservation are limited by the high cost and low flexibility of production ( Deller et al., 2014 ).…”

A decade of coral biobanking science in Australia - transitioning into applied reef restoration

“…Cryopreservation and laser-warming of coral larvae (Daly et al, 2018) is a technology with promise but may be too complex for large-scale or field application. Newer, simpler cryopreservation technologies may provide additional opportunities for coral; for example, cryo-grid technology can easily be used to cryopreserve large numbers of Drosophila embryos and pancreatic cells from various species (Zhan et al, 2021;Zhan et al, 2022). Taronga's CryoDiversity Bank coral acquisitions have only recently expanded to include experimental preservation of other cell types (e.g., embryonic cells: Hagedorn et al, 2012b), life history stages (e.g., larvae: Daly et al, 2018;Cirino et al, 2019), and the microalgal endosymbionts of corals (Symbiodiniaceae: Hagedorn et al, 2010;Hagedorn and Carter, 2015;Lin et al, 2019;Kihika et al, 2022).…”

Stem cell-based multi-tissue platforms to model human autoimmune diabetes

“…This choice should take into consideration the ability of the cells to differentiate into the relevant lineages, the relevance of their HLA typing for T1D, and intellectual property matters. Additionally, methods for shipping and storing the cells that are compatible with long-distance collaborations need to be established, similar to what has recently been described for pancreatic islets [ 141 ]. There are indeed very few institutions that can generate all relevant cell types in the same location.…”