VITRIFICATION FOR TISSUE ENGINEERED PANCREAS

组织工程胰腺的玻璃化冷冻

基本信息

批准号：
6549917
负责人：
Ying Song
金额：
$ 10.54万
依托单位：
ORGAN RECOVERY SYSTEMS, INC.
依托单位国家：
美国
项目类别：
财政年份：
2002
资助国家：
美国
起止时间：
2002-09-30 至 2004-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6549917
关键词：
cryopreservation cryoprotective agents freezing insulin dependent diabetes mellitus insulin sensitivity /resistance nuclear magnetic resonance spectroscopy pancreas pancreatic islets secretion technology /technique development tissue engineering

项目摘要

DESCRIPTION (provided by applicant): According to current estimates from the American Diabetes Association, there are approximately 16 million diabetics in the U.S. in 2000, with 600,000 to 800,000 afflicted with Type I insulin-dependent diabetes (IDD). Tissue engineered pancreatic substitutes have the potential of providing a more physiologic and less invasive treatment of IDD relative to daily insulin injections. The US market for tissue-engineered bioartificial pancreas is currently estimated to be about $2.5 billion. The market for pancreas regeneration products is predicted to expand at a 6.8% compound rate for the next 10 years due to increases in the incidence of diabetes. A significant hurdle for deployment of such constructs is an effective means for long-term storage and transportation to permit worldwide product distribution. Ice formation within tissue matrices causes matrix damage in three-dimensional structures during "traditional" cryopreservation by freezing. The purpose of this proposal is to evaluate an ice-free cryopreservation method, vitrification, using mouse insulinomas encapsulated in calcium alginate/poly-L-lysine as a model system. Vitrification has previously proven to be effective for storage of complex tissues such as blood vessels and articular cartilage. In this proposal the effects of vitrification and a "traditional" freezing method, employing dimethylsulfoxide and control rate cooling, upon encapsulated cell viability and functions will be investigated. Test methods will include cell viability assays, insulin secretion in response to glucose, and morphological evaluation of capsule integrity. A significant part of these studies will consist of determining the penetration rates of cryoprotectants into encapsulated cell systems by nuclear magnetic resonance (NMR) and the effects of such exposure upon cell viability and functions. These observations will permit optimization of the existing procedure to be used for the vitrification of encapsulated cells, incorporating a novel synthetic ice blocking compound to promote vitrification at lower concentrations of cryoprotectants, thereby, reducing osmotic stresses and cytotoxicity. If vitrification is shown to be effective for storage of encapsulated cell constructs, these studies will be extended in a Phase II SBlR proposal to include in vivo testing of the mouse insulinoma cell model as well as alternative encapsulated cell systems.

描述（申请人提供）：根据美国糖尿病协会目前的估计，2000年美国大约有1600万糖尿病患者，其中60万至80万患有I型胰岛素依赖型糖尿病（IDD）。相对于每日胰岛素注射，组织工程胰腺替代品有可能为 IDD 提供更生理性和更少侵入性的治疗。美国组织工程生物人工胰腺市场目前估计约为 25 亿美元。由于糖尿病发病率的增加，预计未来 10 年胰腺再生产品市场将以 6.8% 的复合增长率扩张。部署此类结构的一个重大障碍是长期储存和运输以允许全球产品分销的有效手段。在“传统”冷冻保存过程中，组织基质内的冰形成会导致三维结构中的基质损伤。该提案的目的是使用海藻酸钙/聚-L-赖氨酸封装的小鼠胰岛素瘤作为模型系统来评估无冰冷冻保存方法（玻璃化）。玻璃化冷冻先前已被证明对于保存血管和关节软骨等复杂组织是有效的。在该提案中，将研究玻璃化和“传统”冷冻方法（使用二甲基亚砜和控制速率冷却）对封装细胞活力和功能的影响。测试方法将包括细胞活力测定、响应葡萄糖的胰岛素分泌以及胶囊完整性的形态学评估。这些研究的一个重要部分将包括通过核磁共振（NMR）确定冷冻保护剂进入封装细胞系统的渗透率以及这种暴露对细胞活力和功能的影响。这些观察结果将允许优化用于封装细胞玻璃化的现有程序，掺入新型合成冰阻化合物以在较低浓度的冷冻保护剂下促进玻璃化，从而减少渗透应激和细胞毒性。如果玻璃化被证明对封装细胞构建体的储存有效，这些研究将在 II 期 SBlR 提案中扩展，包括小鼠胰岛素瘤细胞模型以及替代封装细胞系统的体内测试。