Fast Freezing Processes in Tissues

组织中的快速冷冻过程

基本信息

批准号：
10798699
负责人：
Ram Devireddy
金额：
$ 8.53万
依托单位：
LOUISIANA STATE UNIV A&M COL BATON ROUGE
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-06-01 至 2024-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10798699
关键词：
Artificial tissue Award Calorimetry Cell Separation Cells Collagen Cryopreservation Cryoprotective Agents Data Dermal Development Diamond Differential Scanning Calorimetry Discipline Disparate Education Engineering Equipment Excision Fibroblasts Formulation Freezing Funding Gel Goals Heating Heterogeneity Instruction Knowledge Liver Measurement Measures Methodology Methods Microfabrication Microscopy Modeling National Institute of General Medical Sciences Optics Process Protocols documentation Research Resources Scanning System Techniques Technology Testing Thermodynamics Tissue Engineering Tissues United States National Institutes of Health Water biological systems biophysical properties cold temperature design extracellular infrastructure development instrument neonatal human predicting response rational design sensor undergraduate student

项目摘要

PROJECT SUMMARY (ORIGINAL) The goal of the research is to advance the formulation of cryopreservation protocols for biological systems using fundamental biophysical parameters. At present, crucial gaps exist in our knowledge of the biophysical parameters governing the states of intra- and extra-cellular water during a fast freezing process. This proposal aims to redress this crucial gap by introducing two new and effective techniques: (a) a measurement technique based on microscale thermoelectric sensors, engineered using microfabrication techniques suitable for use with artificial tissues and (b) a measurement technique based on a combination of calorimetry and low temperature microscopy suitable for use with native tissues. Specifically, the project will: (1) design fabricate and test microscale thermoelectric sensors to measure fast freezing processes in isolated cells (Neonatal Human Dermal fibroblasts, NHDFs) and artificial tissues (NHDFs embedded in a collagen gel sheet) with and without Cryoprotective Agents (CPAs) and (2) develop a combination of calorimetric and low temperature microscopy (directional solidification) methods to assess fast freezing processes in NHDFs and native (mammalian liver) tissue sections with and without CPAs. CPA addition and removal in both tissue (artificial and native) systems will be modeled using irreversible thermodynamic models. These integrated methods from disparate disciplines will lead to rational design and development of freezing processes for cryopreservation of donated tissues, an extremely scarce resource, as well as artificially engineered tissues. The education and infrastructure development part of this NIH AREA 15 proposal includes both instructional and research components for LSU undergraduate students. PROJECT SUMMARY (NIGMS Supplemental Award) The NIGMS supplemental (equipment) award requests funds to purchase a state of the art differential scanning calorimeter (DSC 8500) to enhance the quality of the data obtained in Aim 2 of the project. The new instrument will allow us to limit measurement errors and to assess the true contribution of cell heterogeneity. In addition, the new instrument will controllably freeze cells to a much higher rates (~750 ˚C/min) thus allowing us to fully accomplish the goals of the original proposal, i.e., to assess fast freezing processes in tissues.

项目概要（原件）该研究的目标是推进生物系统冷冻保存方案的制定目前，我们对生物物理的了解存在重大差距。该提案控制了快速冷冻过程中细胞内和细胞外水的状态。旨在通过引入两种新的有效技术来弥补这一关键差距：(a) 测量基于微型热电传感器的技术，采用微加工技术设计适用于人造组织和 (b) 基于量热法组合的测量技术和适用于天然组织的低温显微镜具体来说，该项目将：（1）设计。制造和测试微型热电传感器以测量隔离细胞中的快速冷冻过程（新生儿真皮成纤维细胞，NHDF）和人造组织（嵌入胶原凝胶中的 NHDF） (2) 开发量热法和低温法的组合温度显微镜（定向凝固）方法来评估 NHDF 中的快速冷冻过程和两种组织中添加和去除 CPA 的天然（哺乳动物肝脏）组织切片。（人工和天然）系统将使用不可逆热力学模型进行建模。来自不同学科的方法将导致冷冻工艺的合理设计和开发冷冻保存极为稀缺的捐赠组织以及人工工程组织。 NIH AREA 15 提案的教育和基础设施发展部分包括教学以及路易斯安那州立大学本科生的研究部分。项目摘要（NIGMS 补充奖） NIGMS 补充（设备）奖励要求资金购买最先进的差速器扫描量热仪 (DSC 8500)，以提高项目目标 2 中获得的数据的质量。新仪器将使我们能够限制测量误差并评估细胞的真正贡献此外，新仪器能够以更高的速率可控地冷冻细胞（~750）。 ℃/min），从而使我们能够完全实现最初提案的目标，即评估快速冷冻组织中的过程。