KLF2 Mediated HIF-1 Regulation and Macrophage Activation

描述(由申请人提供)：炎症反应在调节广泛的生理和病理状态方面至关重要。组织巨噬细胞是这种反应的中心调节器--从启动到消退炎症。最近的研究发现，低氧诱导因子-1α(HIF-1α)是巨噬细胞活化功能的关键调节因子。结合使用增益和功能损失的方法，PI已经确定KLF2是一种新的HIF-1α表达和功能的内源性调节因子。具体地说，我们的研究表明：(1)KLF2抑制HIF-1的表达和转录活性；(2)改变KLF2的表达影响HIF-α靶基因的表达、ATP的产生、细胞因子/基质金属蛋白酶的表达以及巨噬细胞的细菌/肿瘤杀伤活性。在这项建议中，将采用分子和遗传学相结合的方法(1)确定KLF2介导的抑制HIF1α表达的分子基础，(2)评估改变KLF2水平对缺氧或内毒素介导的巨噬细胞激活的影响，以及(3)评估改变KLF2水平对体内缺氧或内毒素介导的巨噬细胞功能的影响。这些研究将为申请者实现将炎症的基本机制转化为新疗法的开发的长期目标提供基础。通过K99/R00奖支持这一项目将在候选人成为独立调查员的过程中发挥关键和必要的作用。他的直接目标是通过额外的密集指导、技术培训和广泛的智力发展来巩固他的研究经验，这将直接产生于这项提议。高度结构化的职业发展计划是这项建议的内在组成部分，旨在极大地提高候选人长期职业目标的实现：作为NIH资助的教员，独立完成免疫细胞生物学研究。

DESCRIPTION (provided by applicant): The inflammatory response is critical in regulating a broad spectrum of physiologic and pathologic states. The tissue macrophage is a central regulator of this response - from initiation to resolution o inflammation. Recent studies have identified Hypoxia-inducible Factor 1alpha(HIF-1 alpha) as a key regulator of macrophage activation function. Using a combination of gain- and loss-of-function approaches, the PI has identified KLF2 as a novel endogenous regulator of HIF-1 alpha expression and function. Specifically, our studies show that (1) KLF2 inhibits HIF-1 expression and transcriptional activity; (2) altering KLF2 expression affects HIF-lalpha target gene expression, ATP production, cytokine/MMP expression, and bacterial/tumoricidal activity of macrophages. In this proposal a combination of molecular and genetic approaches will be undertaken (1) to determine the molecular basis for KLF2-mediated inhibition of HIFlalpha expression, (2) to evaluate the effect of altering KLF2 levels on hypoxia or LPS mediated activation of macrophages, and (3) to assess the effect of altering KLF2 levels on hypoxia or LPS-mediated macrophage function in vivo. These studies will provide the foundation for the applicant to achieve his long-term goals of translating basic mechanisms of inflammation toward the development of novel therapies. Support of this project via a K99/R00 award would play a pivotal and requisite role in the candidate's development into an independent investigator. His immediate goal is to solidify his research experience through additional intensive mentorship, technical training, and broad intellectual development that will result directly from this proposal. A highly structured career development plan is an intrinsic component of this proposal and is designed to greatly enhance accomplishment of the candidate's long-term career goal: independent performance of immune cell biology research as an NIH-funded faculty member.