Department of Electronic Science and Technology, University of Science and Technology of China, Hefei, Anhui 230027, China.
Biomater Sci. 2019 Feb 26;7(3):889-900. doi: 10.1039/c8bm01231h.
Cell-laden alginate hydrogel microfibers are particularly useful for building and repairing complex tissues because they are long, thin, and flexible. Therefore, they have important application value in regenerative medicine and clinical treatments. Cryopreservation is indispensable in order to ensure their "off-the-shelf" ready availability. Ice-free vitrification is considered an ideal method to preserve stem cell constructs (from cells to the overall ultrastructure of hydrogel). However, the vitrification process for preserving cell constructs requires highly toxic and cell membrane permeable cryoprotective agents (pCPA) and even requires the assistance of complex physical field based space warming technology. Therefore, a simple and feasible method is urgently needed. In addition, there are no reports about microfiber vitrification, as reports are limited to microcapsules. In this study, a novel device with nylon mesh for vitreous cryopreservation of hydrogel microfibers is developed to achieve ultra-rapid heat transfer by effectively suppressing film boiling during cooling. This may provide a low-toxic and cost-effective method for vitrification of cell-laden hydrogel microfibers with ultra-low concentrations of pCPA, facilitating their application in regenerative medicine.
细胞负载的海藻酸盐水凝胶微纤维在构建和修复复杂组织方面特别有用，因为它们长而细且具有弹性。因此，它们在再生医学和临床治疗中有重要的应用价值。为了确保它们“随时可用”，冷冻保存是必不可少的。无冰玻璃化被认为是保存干细胞构建体（从细胞到水凝胶的整体超微结构）的理想方法。然而，保存细胞构建体的玻璃化过程需要高度有毒和细胞膜可渗透的细胞保护剂（pCPA），甚至需要复杂的基于物理场的空间加热技术的辅助。因此，迫切需要一种简单可行的方法。此外，关于微纤维玻璃化的报道很少，因为报道仅限于微胶囊。在这项研究中，开发了一种带有尼龙网的新型装置，用于通过在冷却过程中有效抑制膜沸腾来进行水凝胶微纤维的玻璃化冷冻保存。这可能为使用超低浓度 pCPA 的细胞负载水凝胶微纤维的玻璃化提供一种低毒性且具有成本效益的方法，从而促进其在再生医学中的应用。
