MCP-1 induced gene expression in cardiovascular disease

描述(申请人提供)：许多最近的报告提供了强有力的证据表明，单核细胞趋化蛋白-1在缺血性心脏病(IHD)的发展中发挥了重要作用，在美国500万例人类心力衰竭病例中，IHD是主要原因，但其潜在机制尚不清楚。我们推测，MCP-1诱导单核细胞基因表达的改变，以及随后产生的细胞因子和其他生物活性分子，以及MCP-1对心肌主要细胞类型的可能直接作用，都可能导致IHD的发生。IHD可能是这些事件相互作用的结果，这些事件涉及多种细胞类型和许多生物活性分子。因此，对分离细胞的体外研究不能准确地反映IND所涉及的相互作用。另一方面，基因组学方法可以发现心脏中表达变化导致IHD发生发展的基因。这种方法虽然不可能在人类身上进行，但可以在合适的动物模型上进行。我们已经开发出一种转基因小鼠模型，它忠实地概括了人类IRD的大部分特征。使用这个模型很有可能发现新的基因，我们发现了一种以前未知的MCP-1诱导蛋白(MCPIP)。在这一总体目标下，我们建议实现以下具体目标：1.利用基因芯片技术鉴定转基因小鼠CMC靶向表达单核细胞趋化蛋白1(MCP 1)后，在IHD发育过程中脑室基因表达的变化。2.)确定新的MCPIP的功能：a)确定MCPIP的表达是否导致细胞死亡，b)MCP-L及其受体CCR2是否促进这种死亡，c)细胞死亡是否具有凋亡的特征，d)MCPIP是否具有转录因子样活性，以及这种活性所需的结构特征是否也是细胞死亡诱导活性所必需的。3.)通过测试a)通过靶向表达bc12来阻止单核细胞凋亡，或b)通过在心肌细胞中缺失Fas或表达sFas来阻止细胞凋亡，来评估细胞凋亡在MCP 1诱导的心血管疾病发展中的作用。本文提出的方法将识别MCP-L诱导的与IHD无关的已知基因和与IHD相关的未知功能新基因的表达变化。这些基因可能揭示干预IND的新靶点和具有预后价值的基因。

DESCRIPTION (provided by applicant): Many recent reports provide strong evidence that MCP- 1 plays a major role in the development of ischemic heart disease (IHD) that is responsible for the majority of the 5 million human heart failure cases in the US, but the underlying mechanism is not known. We postulate that MCP-1-induced gene expression changes in the monocytes and the consequent production of cytokines and other biologically active molecules, as well as possible direct effects of MCP- 1 on the major cell types in the myocardium can lead to the development of IHD. IHD probably develops as a net consequence of the interplay of these events which involve many cell types and many biologically active molecules. Therefore in vitro studies on isolated cells cannot accurately reflect the interactions involved in IND. On the other hand a genomic approach can discover the genes whose altered expression in the heart leads to the development of IHD. Such an approach, although not possible on humans, can be done on a suitable animal model. We have developed a transgenic murine model that faithfully recapitulates most features of human IRD. Use of this model has a high likelihood of discovering novel genes as illustrated by our discovery of a previously unknown MCP-1-induced protein (MCPIP). With this overall objective we propose to pursue the following specific aims: 1.) Identify gene expression changes that occur in the ventricle during IHD development induced by targeted expression of MCP 1 in the CMC of transgenic mice using gene chip technology. 2.) Determine the function of the novel MCPIP: a) Determine whether a) MCPIP expression causes cell death, b) this death is enhanced by MCP-l and its receptor CCR2, c) whether the cell death shares features characteristic of apoptosis, d) MCPIP has a transcription factor-like activity and whether structural features required for this activity are also required for the cell death-inducing activity. 3.) Assess the role of apoptosis in the development of MCP 1-induced cardiovascular disease by testing whether a) prevention of monocyte apoptosis by targeted expression of Bc12 or b) prevention of apoptosis by absence of Fas or expression of sFas in the myocytes would delay or rescue the development of the disease. The approach proposed here will identify MCP-l induced alterations in the expression of known genes not previously implicated in IHD and novel genes of unknown function that are involved in IHD. These genes are likely to reveal novel targets for intervention in IND and genes with prognostic value.