Protein-Releasing Microporous Scaffolds for Cell Replacement Therapy

用于细胞替代疗法的蛋白质释放微孔支架

• 批准号: 8977538
• 负责人: Lonnie D Shea
• 金额: $ 0.51万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-01 至 2015-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8977538
• 关键词: Protein; Releasing; Microporous; Scaffolds; Cell

DESCRIPTION (provided by applicant): Cell-based therapies provide a novel approach to treating chronic diseases. Recapitulating a damaged organ's function by secreting hormones or other factors is dependent upon successful engraftment of transplanted cells. Engraftment of the transplanted cells requires that cells survive the initial hypoxic environment following transplantation, connect with the host vasculature for exchange of nutrients and waste products and also deliver secreted factors into the circulation. Doing this requires creating an environment that promotes long term function of the transplanted cells. If the cell supply is limited, approaches to expand the transplant graft in vivo may also be important. We propose to address the hypothesis that micro-porous polymer scaffolds capable of delivering biologically active peptides can create a microenvironment to promote cell engraftment, survival and proliferation. A classic paradigm for cell-based therapy is islet transplantation for treatment of type 1 diabetes in which destruction of insulin-secreting beta cells in the pancreas results in hyperglycemia and its complications. Recent trials have provided proof of concept that islet transplantation can be efficacious, yet problems remain. To address these problems, we are proposing to transplant islets on microporous scaffolds capable of releasing proteins that can influence the host tissue (e.g., vascularization) or enhance the functionality of the transplanted islets. These factors will condition the microenvironment to promote islet engraftment, survival, and function. We have recently shown that microporous scaffolds can serve as a platform for islet transplantation. The Specific Aims are as follows. (i) 1) To investigate the hypothesis that the scaffold architecture, as defined by porosity, pore size, and stability, will influence islet engraftment and function. (ii) To address the hypothesis that use of a polymer scaffold to deliver angiogenic factors will improve islet survival and function post-transplantation in a murine model of diabetes. (iii) To test the hypothesis that polymer scaffolds delivering factors that inhibit islet cell death and/or increase islet cell mass post-transplantation will enhance islet engraftment and function. (iv) To determine whether delivering a combination of growth factors that affect different processes (e.g., angiogenesis and islet cell survival and/or proliferation) is more efficacious than delivering a single factor. These studies have the potential to substantially advance cell therapies for islet transplantation.

描述（由申请人提供）：基于细胞的疗法为治疗慢性疾病提供了一种新颖的方法。通过分泌激素或其他因素来概括器官的功能取决于成功地植入移植细胞。移植细胞的植入要求移植后的初始低氧环境，与宿主脉管系统连接以交换营养和废物产物，并将分泌的因子传递到循环中。这样做需要创建一个促进移植细胞的长期功能的环境。如果细胞供应有限，则在体内扩展移植移植物的方法也可能很重要。我们建议解决以下假设：能够递送生物活性肽的微孔聚合物支架可以创建微环境以促进细胞植入，存活和增殖。用于基于细胞的治疗的经典范式是治疗1型糖尿病的胰岛移植，其中胰腺中胰岛素分泌β细胞的破坏会导致高血糖及其并发症。最近的试验提供了概念证明，即胰岛移植可以有效，但问题仍然存在。为了解决这些问题，我们提议在能够释放可能影响宿主组织（例如血管化）或增强移植胰岛功能的微孔支架上移植胰岛。这些因素将调节微环境以促进胰岛植入，生存和功能。我们最近表明，微孔支架可以用作胰岛移植的平台。具体目标如下。 （i）1）调查以下假设：孔隙率，孔径和稳定性定义的支架结构将影响胰岛的植入和功能。 （ii）解决以下假设：在糖尿病的鼠模型中，使用聚合物支架提供血管生成因子将改善胰岛存活和功能。 （iii）测试以下假设：聚合物支架提供抑制胰岛细胞死亡和/或增加移植后胰岛细胞质量的因子将增强胰岛的植入和功能。 （iv）确定提供影响不同过程的生长因子的组合（例如，血管生成和胰岛细胞存活和/或增殖）是否比提供单个因子更有效。这些研究有可能大大推进胰岛移植的细胞疗法。