Cryopreservation of tissue engineered substitutes

组织工程替代品的冷冻保存

• 批准号: 7143032
• 负责人: ATHANASSIOS SAMBANIS
• 金额: $ 32.04万
• 依托单位: GEORGIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7143032
• 关键词: artificial endocrine pancreas; bioengineering /biomedical engineering; biomaterial evaluation; cell osmotic pressure; cryopreservation; cryoprotective agents; cytotoxicity; laboratory mouse; membrane permeability; neoplastic cell culture for noncancer research; pancreatic islet neoplasm; pancreatic islet transplantation; pancreatic islets; technology /technique development; tissue engineering

DESCRIPTION (provided by applicant): Tissue engineered substitutes have the potential to provide effective, functional replacements of failing tissues and organs and as such help resolve the current transplantation crisis. To realize its potential, tissue engineering must generate substitutes that can be preserved in the long-term. Preservation is essential for off-the-shelf availability, storage and distribution of constructs fabricated at a large-scale at centralized locations, as well as for sterlity testing and quality control. The long-range goal associated with this research program is to develop a fundamental understanding of how the various cryopreservation parameters affect cellular and tissue construct function, and on the basis of this knowledge to develop widely applicable preservation protocols. The objective of this application is to evaluate the effect of ice-forming and ice-free cryopreservation on cell viability and construct function for a model pancreatic tissue substitute consisting of insulin-secreting cells and a hydrogel biomaterial. The central hypothesis is that entire tissue engineered substitutes can be successfully vitrified, while maintaining key structural and functional features of the cellular and biomaterial components; vitrification produces superior outcomes relative to conventional, ice-forming cryopreservation in terms of both construct integrity and functionality. Guided by strong preliminary data, the hypothesis will be addressed by the following 3 specific aims: 1) determine cell osmotic tolerance limits and cryoprotectant cytotoxicity and define the domain of conditions under which to cryopreserve cells used in tissue substitutes; 2) characterize in vitro the effect of cryopreservation on construct structure and function; 3) evaluate the in vivo functionality of cryopreserved substitutes. The effect of cryopreservation on cells will be assessed on the basis of cell viability, apoptosis, stress protein expression, and metabolic and secretory functions; and on biomaterials on the basis of their structural integrity and functionality. The approach is innovative, as it focuses on studying the effects of cryopreservation on both the cellular and biomaterial components of a three-dimensional (3D) tissue substitute. The proposed research is significant, as it will generate new fundamental information on the science of cryopreservation, provide a quantitative framework for the rational design of cryopreservation protocols, and identify key design features of tissue substitutes that enable their cryopreservation.

描述（由申请人提供）：组织工程替代物具有提供有效的功能替代组织和器官的功能替代，因此有助于解决当前的移植危机。为了实现其潜力，组织工程必须产生可以长期保存的替代品。保存对于在集中位置的大规模制造的建筑物的现成可用性，存储和分布以及静止测试和质量控制至关重要。与该研究计划相关的远程目标是对各种冷冻保存参数如何影响细胞和组织构建功能的基本了解，并基于这些知识，以开发广泛适用的保存方案。该应用的目的是评估模型胰腺分泌细胞和水凝胶生物材料组成的模型胰腺组织替代物的细胞活力和构造功能的影响。中心假设是，可以成功地将整个组织工程替代品成功地玻璃化，同时保持细胞和生物材料成分的关键结构和功能特征。玻璃化在构造完整性和功能方面，相对于常规的，制冰的冷冻保存提供了较高的结果。在强大的初步数据的指导下，该假设将通过以下3个特定目的来解决：1）确定细胞渗透耐受性限制和冷冻保护剂细胞毒性，并定义了在组织替代物中使用冷冻细胞的条件域； 2）在体外表征冷冻保存对结构和功能的影响； 3）评估冷冻保存替代物的体内功能。冷冻保存对细胞的影响将根据细胞活力，凋亡，应激蛋白表达以及代谢和分泌功能评估。以及基于生物材料的结构完整性和功能。该方法是创新的，因为它着重研究冷冻保存对三维（3D）组织替代品的细胞和生物材料成分的影响。拟议的研究非常重要，因为它将生成有关冷冻保存科学的新基本信息，为冷冻保存方案的合理设计提供了定量框架，并确定了构成组织替代品的关键设计特征，以实现其冷冻保存。