SusCHEM: Fundamental Studies on Lyopreservation of Adult Stem Cells

1605425何晓明在室温下以假死状态冷冻保存活细胞用于建库，使得实现细胞的低成本维护和方便分配成为可能。 细胞的现成可用性对于基于细胞的疗法的广泛应用和最终成功至关重要，所述疗法涉及组织工程、再生医学、细胞移植、输血和干细胞疗法。本项目的目的是进行系统研究，以了解海藻糖（一种无毒糖）在冷冻和干燥含海藻糖的人脂肪源性干细胞（hADSC）以及在室温下储存干燥细胞时的保护作用。由于海藻糖已被用于许多低等生物在自然界中的极端寒冷和干旱中生存，因此假设负载海藻糖的干细胞将表现出类似的行为。 该项目将通过促进细胞冷冻保存技术的发展，为基于细胞的医学治疗的成功提供技术支持，从而对改善医疗保健产生重大影响。使用无毒糖（海藻糖）替代有毒化学物质（例如，二甲基亚砜或DMSO）用于细胞库与NSF SusCHEM倡议很好地一致，以用地球上丰富的、廉价的和良性的材料取代有毒化学品。为了了解在环境温度下以假死状态干燥活细胞用于银行的基础科学，提出了三个具体的研究任务。这些包括（i）分别使用冷冻干燥显微镜和台式冷冻干燥机对小样品和大样品研究冷冻干燥参数对干燥海藻糖溶液的动力学（对于原代hADSC的冻干保存是重要的）和对干燥产物的微观形态的影响;（ii）海藻糖的生物物理响应的模拟和实验定量-将负载的hADSC冷冻和干燥，包括细胞脱水和细胞内冰形成，这对于细胞存活是重要的;和（iii）在冷冻干燥和在环境温度下储存后，分析原代hADSC的形态、存活、长期增殖和干细胞性质和功能。通过干细胞基因和蛋白质标记物的表达及其成脂、成骨和成软骨分化的能力来评估干细胞的性质和功能。预计在最佳条件下冷冻干燥和长期储存后，原代hADSCs的存活率和完整功能较高。CBET部门生物技术和生物化学工程项目的这一奖项由材料研究部门生物材料项目共同赞助。

1605425 He, Xiaoming Lyopreservation of living cells for banking in a state of suspended animation at ambient temperature makes it possible to achieve low-cost maintenance and convenient distribution of the cells. The ready availability of cells is crucial for the wide application and eventual success of cell-based therapies involving tissue engineering, regenerative medicine, cell transplantation, blood transfusion, and stem cell therapy. The objective of this project is to perform a systematic investigation to understand the protective effect of trehalose, a nontoxic sugar, during freezing and drying of trehalose-laden human adipose-derived stem cells (hADSCs) and in banking the dried cells at ambient temperature. As trehalose has been used for many lower organisms to survive extreme cold and drought in nature, it is hypothesized that trehalose-laden stem cells will behave similarly. This project will have a significant impact on improving healthcare by facilitating the development of cell lyopreservation as an enabling technology for the success of cell-based medical treatments. The use of a nontoxic sugar (trehalose) to replace toxic chemicals (e.g., dimethyl sulfoxide or DMSO) for cell banking is well aligned with the NSF SusCHEM initiative to replace toxic chemicals with earth-abundant, inexpensive, and benign materials. To understand the fundamental science of drying living cells for banking in a state of suspended animation at ambient temperature, three specific research tasks are proposed. These include (i) investigation of the effect of freeze-drying parameters on the kinetics of drying trehalose solutions important for lyopreservation of primary hADSCs and on the microscopic morphology of the dried products, using freeze-drying microscopy and a benchtop freeze-dryer for small and large samples, respectively; (ii) simulation and experimental quantification of the biophysical responses of the trehalose-laden hADSCs to freezing and drying including cell dehydration and intracellular ice formation important for cell survival; and (iii) analysis of the morphology, survival, long-term proliferation, and stem cell properties and functions of the primary hADSCs after freeze-drying and banking at ambient temperature. The stem cell properties and functions will be assessed by the expression of stem cell gene and protein markers and their capability of adipogenic, osteogenic, and chondrogenic differentiation. A high survival and intact function of the primary hADSCs are anticipated after freeze-drying and long-term storage at ambient temperature under optimal conditions.This award by the Biotechnology and Biochemical Engineering Program of the CBET Division is cosponsored by the Biomaterials Program of the Division of Materials Research.