IN VIVO ROLE OF CRP IN TRANSGENIC MICE

本计划的总体目标是定义C++的角色 反应蛋白(CRP)在宿主防御机制中的作用一直以来 在很大程度上基于体外研究的假设，C反应蛋白起作用 在炎症刺激后的早期免疫前阶段。一个 C反应蛋白在体内炎症反应过程中的明确作用 还没有建立起来。在前一个资金期，本金 研究人员培育出表达兔C反应蛋白的转基因小鼠 一种金属硫蛋白(MTT)或PEPCK启动子 C反应蛋白的表达不依赖于炎症刺激。这些转基因生物 动物已经被用于三种炎症的小鼠模型 包括内毒素和PAF的全身效应，这是一个肺泡模型 炎症和单关节关节炎模型。在这三个国家中 表达CRP的转基因小鼠系统已显示出可重复性 抗炎作用。目前的建议是延长研究时间。 C反应蛋白参与炎症反应的机制 假设是，C反应蛋白的作用取决于它的能力 结合磷胆碱(PC)、C反应蛋白(CRP)可影响细胞因子和 黏附分子和抗炎作用对抗原的影响 关节炎是通过抑制T细胞的激活而介导的 免疫过程的传入臂。这些假设将通过以下方式进行验证： 1)生产表达突变的CRP的转基因小鼠 设计为不能与PC结合；2)测量CRP的效果 单核细胞、脾细胞和脾细胞炎性细胞因子基因表达的研究 中性粒细胞；3)控制C反应蛋白水平 在关节炎模型中启动免疫反应后 测定C反应蛋白对T细胞活化的影响。

The overall objective of this program is to define the role of C reactive protein (CRP) in host defense mechanisms. It has been hypothesized, based largely on in vitro studies, that CRP functions during the early preimmune stages following inflammatory stimulus. A clear role for CRP during the course of inflammatory response in vivo has not been established. In the prior funding period the principal investigator has generated transgenic mice which express rabbit CRP with either a metallothionein (MTT) or PEPCK promoter which has made possible expression of CRP independent of inflammatory stimuli. These transgenic animals have been used in three mouse models of inflammation which include the systemic effects of LPS and PAF, a model of alveolar inflammation and a model of monoarticular arthritis. In all three systems CRP expressing transgenic mice have shown reproducible antiinflammatory effects. The present proposal is to extend the studies on the mechanisms of CRP as a participant in inflammation, The working hypotheses are that the effects of CRP are dependent on its ability to bind phosphocholine (PC), CRP can influence expression of cytokines and adhesion molecules, and antiinflammatory effects on antigen enduced arthritis are mediated by inhibition of T cell activation during the afferent arm of the immune process. These hypotheses will be tested by: 1) producing transgenic mice expressing a mutant CRP which has been designed to be incapable of PC binding; 2) measuring the effects of CRP on inflammatory cytokine gene expression in monocytes, splenocytes and neutrophils; and 3) manipulating the level of CRP before, during and after the initiation of the immune response in a model of arthritis to determine the effect of CRP on T cell activation.