IN VIVO ROLE OF CRP IN TRANSGENIC MICE

CRP 在转基因小鼠体内的作用

• 批准号: 3161225
• 负责人: DAVID SAMOLS
• 金额: $ 16.76万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-08-01 至 1995-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3161225
• 关键词: acute phase protein; allergic arthritis; amyloid proteins; bacterial endocarditis; binding proteins; biological models; chemical binding; complement pathway; enzyme linked immunosorbent assay; gene expression; genetically modified animals; histochemistry /cytochemistry; inflammation; laboratory mouse; molecular site; phosphorylcholine; protein structure function; site directed mutagenesis; tissue /cell culture; transfection

C-reactive protein (CRP) is an acute phase protein of hepatic origin in man whose plasma concentration increases markedly in response to a wide variety of inflammatory stimuli. CRP is a binding protein which, when bound to one of its ligands, has been found capable of activating complement, and affecting the function of phagocytic cells. CRP also contains tuftsin-like peptides and proteolytic fragments of CRP can stimulate inflammatory cells. These properties along with evolutionary conservation of the protein (which is even found in some invertebrates), have been interpreted as indicating that CRP functions to modulate the inflammatory response. The mouse, in contrast to most vertebrates, does not synthesize a significant quantity of CRP in response to inflammatory stimuli. We have taken advantage of this evolutionary oddity and produced transgenic mice capable of expressing rabbit CRP in order to define the functional role of CRP in vivo. These animals will be employed to assess the effects of rabbit CRP in three established mouse models of inflammation. We will: 1) Initially characterize the properties of CRP in our established transgenic mouse lines. 2) Determine the pathophysiologic and morphologic effects of transgenic CRP on endotoxic shock, antigen-induced acute arthritis and Lactobacillus induced carditis in these animals. 3) Test the in vivo importance of the phosphorylcholine (PC) binding domain of CRP since PC is a ubiquitous substrate to which CRP binds avidly. This domain will be altered by site directed mutagenesis of the rabbit CRP gene and, after confirmation that these mutants are unable to bind PC (following expression in transfected cell lines), will be employed to produce additional transgenic mice. The effects of altering the PC binding domain on the functional properties of CRP will be tested in the models outlined in 1) and 2) above.

C反应蛋白（CRP）是人类中肝脏起源的急性相蛋白 其血浆浓度响应于多种的血浆浓度明显增加 炎症刺激。 CRP是一种结合蛋白，当结合到一个时 已发现其配体能够激活补体，并且 影响吞噬细胞的功能。 CRP还包含类似塔夫菌的 CRP的肽和蛋白水解片段可以刺激炎症细胞。 这些特性以及蛋白质的进化保守性（ 甚至在某些无脊椎动物中发现），被解释为指示 该CRP功能可调节炎症反应。 与大多数脊椎动物相比，鼠标不会合成 响应炎症刺激的大量CRP。 我们有 利用这种进化的奇怪性并产生了转基因小鼠 能够表达兔子CRP以定义 CRP在体内。 这些动物将被用来评估 兔子CRP在三种已建立的小鼠炎症模型中。 我们将：1） 最初表征我们已建立的转基因中CRP的特性 鼠标线。 2）确定的病理生理和形态学作用 转基因CRP在内毒性休克，抗原引起的急性关节炎和 乳杆菌在这些动物中诱发心脏炎。 3）测试体内 CRP的磷酸胆碱（PC）结合结构域的重要性，因为PC为 CRP热量结合的无处不在的底物。 这个领域将是 通过位点定向诱变的兔子CRP基因的诱变，之后 确认这些突变体无法绑定PC（以下表达 在转染的细胞系中），将采用额外的 转基因小鼠。 改变PC结合域对 CRP的功能性能将在1中概述的模型中进行测试 2）上面。