Optical Imaging of Beta-Cell Function and Engraftment

β 细胞功能和植入的光学成像

• 批准号: 6666714
• 负责人: MASSIMO M. TRUCCO
• 金额: $ 14.31万
• 依托单位: CHILDREN'S HOSP PITTSBURGH/UPMC HLTH SYS
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-30 至 2004-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6666714
• 关键词: NOD mouse; T lymphocyte; bioimaging /biomedical imaging; bioluminescence; cell line; gene targeting; genetic recombination; genetically modified animals; green fluorescent proteins; insulin; intracellular transport; laboratory mouse; leukocyte activation /transformation; luciferin monooxygenase; optics; pancreas imaging /visualization; pancreatic islet function; pancreatic islet transplantation; reporter genes; somatostatin; transcription factor

DESCRIPTION (provided by applicant): The clinical practicality of treating type 1 diabetics with islet transplants obviating the need for exogenous insulin replacement became evident once the first seven successful transplants were officially announced by the Edmonton group. This study proved two major points: the technical feasibility of improved islet isolation procedures and transplantation modalities and second, that more than one allogeneic donor is required to obtain an appropriate ¿-cell mass to treat one recipient. Apparently, necrotic and apoptotic processes during the isolation procedure dramatically reduce the number of functional ¿-cell mass obtainable. Even with an appropriate ¿-cell mass, islet transplants are still susceptible to autoimmune and alloimmune rejection. To protect the graft against the negative consequences of these processes, the Edmonton team used a cocktail of potent immunosuppressive drugs. The recipients are required to maintain this regimen of immunosuppression for their entire lifetime. However, this therapy does pose toxicity risks in that prolonged use of this cocktail can impair kidney and liver function. This concern is a major factor that impedes the introduction of this regimen for routine clinical use to prevent immune rejection of islet transplants in young diabetics. In contrast, tolerance induction strategies, rather than immunosuppression, appear to be the favorable approach to treat children with diabetes. In an attempt to study different tolerogenic protocols, it will become extremely important to be able to follow in vivo the activities of activated T cells simultaneously with the damage inflicted to the transplanted islets. The imaging system we are proposing herein will certainly be valuable to more quickly acquire the knowledge needed to progress from intervening in rodents to rational human trials. These methods should allow non-invasive live cell imaging in live animals. We propose the development of an optical fluorescence and luminescence-based system where the fluorescent and luminescent markers are detectable above physiologic self-fluorescent backgrounds, yet sufficiently discriminative (e.g., green versus red) to allow the monitoring of different cell types simultaneously. These constitute the main goals of this application and the basis upon which the feasibility of our tolerogenic approaches will be carefully evaluated.

描述（由适用提供）：一旦Edmonton Group正式宣布了前七项成功的移植，以胰岛移植的治疗1型糖尿病患者的临床实践消除了对外源性胰岛素置换的需求。这项研究证明了两个主要点：改进的胰岛隔离程序和移植方式的技术可行性，其次，需要多个同种异体供体才能获得适当的细胞质量来治疗一个接受者。显然，在隔离过程中的坏死和凋亡过程大大减少了获得的功能性� -细胞质量的数量。即使有适当的细胞质量，胰岛移植仍然容易受到自身免疫和同种异体免疫的影响。为了保护谷物免受这些过程的负面影响，埃德蒙顿团队使用了大量有效的免疫抑制药物的鸡尾酒。需要接收者在整个生命周期内维持这种免疫抑制措施。但是，这种疗法确实构成了毒性风险，因为长时间使用这种鸡尾酒会损害肾脏和肝功能。这是阻碍该方案引入常规临床用途的主要因素，以防止在年轻糖尿病患者中免疫胰岛移植。相反，耐受性诱导策略，而不是免疫抑制，似乎是治疗糖尿病儿童的有利方法。为了研究不同的耐受性方案，能够在体内遵循激活的T细胞的活性将变得非常重要，而对移植胰岛造成的损害则是非常重要的。我们在此提议的成像系统肯定会很有价值，对于从介入啮齿动物到理性的人类试验所需的知识，这肯定是有价值的。这些方法应允许活动物中的非侵入性活细胞成像。我们提出了基于光荧光和发光系统的开发，在该系统中，荧光和发光标记在物理同盟的自我荧光背景上方可以检测到，但充分歧视（例如，绿色和红色）可以简单地监测不同的细胞类型。这些构成了本应用的主要目标，也是仔细评估我们的耐受性方法的可行性的基础。