INHIBITION OF APOPTOSIS IN PANCREATIC BETA CELLS

表现为葡萄糖反应的胰岛β细胞的短缺 胰岛素分泌一直是广泛性糖尿病发展的主要障碍。 适用于糖尿病的细胞移植疗法。要解决这个问题 问题，我们研究的最终目标是发展扩展 人类贝塔细胞或贝塔细胞前体的种群。这将会 提供大量的细胞，在体外培养，保持葡萄糖- 反应性胰岛素分泌或分化和获取 这是一处房产。这样的细胞可以用于细胞移植。 糖尿病的治疗方法。 目前正在寻求两种方法来扩增人类β细胞和 体外培养的内分泌细胞前体细胞。首先是培养原代细胞 肝细胞生长时细胞外基质的研究 因子/分散因子(HGF/SF)。二是表示优势 细胞中的癌基因，导致基质和生长因子 体外独立生长。随着原代细胞的扩张， 必须将它们从ECM中移除，并聚集成胰岛样细胞 群集(ICC)。然而，扩增的原代细胞从 这种基质导致一种被称为失巢凋亡的形式的细胞凋亡。对于 表达SV40T抗原和H-ras-Val12显性的β细胞系 癌基因，使用cre-lox重组酶去除癌基因 系统在聚合到ICC之前，实现了快速、高效 细胞凋亡。因此，在两种截然不同的情况下，细胞凋亡都会遇到 在试图扩增人类β细胞和β细胞的情况下 文化中的前身。在这项提案中，抑制的方法 一氧化氮抑制剂和腺病毒载体诱导的细胞凋亡 我们将探索如何表达抗凋亡基因。经济衰退带来的影响 抗凋亡基因在原代、未扩增细胞移植中的应用 对人类胰腺内分泌细胞的培养也将进行研究。 这些研究对扩大人口的发展很重要。 用于细胞移植的人β细胞和β细胞前体 糖尿病的治疗方法。

The shortage of pancreatic beta-cells exhibiting glucose-responsive insulin secretion has been a major obstacle to the development of widely applicable cell transplantation therapies for diabetes. To address this problem, the ultimate goal of our research is to develop expanded populations of human beta cells or beta-cell precursors. This would provide a large quantity of cells, grown in vitro, that retain glucose- responsive insulin secretion or the ability to differentiate and acquire this property. Such cells could then be used for cell transplantation therapies for diabetes. Two approaches are being pursued to expand human beta-cells and endocrine cell precursors in vitro. The first is to grow primary cells on extracellular matrix (ECM) in the presence of hepatocyte growth factor/scatter factor (HGF/SF). The second is to express dominant oncogenes in the cells, resulting in matrix and growth factor independent growth in vitro. Following the expansion of primary cells, they must be removed from the ECM and aggregated into islet-like cell clusters (ICCs). However, detachment of the expanded primary cells from the matrix results in a form of apoptosis known as anoikis. For the beta-cell line expressing the SV40 T antigen and H-ras\Val12 dominant oncogenes, removal of the oncogenes using the cre-lox recombinase system, prior to aggregation into ICCs, results in rapid and efficient apoptosis. Thus, apoptosis has been encountered in two distinct situations in attempts to expand human beta cells and beta-cell precursors in culture. In this proposal, approaches to inhibition apoptosis using inhibitors of nitric oxide and adenoviral vectors expressing anti-apoptotic genes will be explored. The effects of the anti-apoptotic genes on transplantation of primary, non-expanded cultures of human pancreatic endocrine cells will also be studied. These studies are important to the development of expanded populations of human beta cells and beta-cell precursors for cell transplantation therapies for diabetes.