Targeting CCR5 Incorporated Into Virus Like Particles

 描述（由申请人提供）： 趋化因子受体CCR 5和CXCR 4是膜蛋白GPCR家族的成员，介导HIV的进入。在本申请中，我们提出开发一种基于NMR的药物发现和优化的新方法，靶向嵌入在病毒样颗粒（VLP）中的CCR 5。我们研究的基本原理是CCR 5富含膜脂筏，这也是VLP形成和出芽的位点，并且VLP将提供由脂质和胆固醇组成的天然膜。因此，我们推测，VLP中产生的细胞系过表达CCR 5将是有价值的模型膜系统的生物物理和药物发现的研究。相对于全细胞系统，VLP具有许多优点，包括：惰性和非代谢系统，纯化和浓缩的能力，以及不存在污染的细胞内组分。具体目标是：（1）通过基于NMR的片段文库筛选发现CCR 5的拮抗剂;（2）将启动最有希望的片段的NMR引导的化学优化。总之，这些研究为开发近期靶向CCR 5和长期靶向CXCR 4的新型抗HIV药物迈出了第一步。据我们所知，之前尚未采用基于VLP的药物发现和优化方法，因此该申请可能被视为“高风险”。尽管如此，正在开发的方法预计将适用于一般的GPCR，这是所有药物的目标约40%，因此这种应用有可能对人类健康产生非常重大的影响。总之，我们认为拟议研究的“高风险”和“高回报”方面使其非常适合R21支持机制。

 DESCRIPTION (provided by applicant): The chemokine receptors CCR5 and CXCR4, which are members of the GPCR family of membrane proteins, mediate the entry of HIV. In this application we propose to develop a new method for NMR-based drug discovery and optimization targeting CCR5 embedded in virus like particles (VLP). The rationale behind our studies is that CCR5 are enriched in membrane lipid rafts, which is also the site of VLP formation and budding, and that the VLP will provide a native membrane consisting of lipids and cholesterol. Accordingly, we hypothesize that VLP produced in cell lines overexpressing CCR5 will be valuable model membrane system for biophysical and drug discovery studies. With respect to whole cell systems, VLP present numerous advantages including: an inert and non-metabolizing system, the ability to purify and concentrate, and the absence of contaminating intracellular components. The specific aims are: (1) Antagonists of CCR5 will be discovered by NMR-based screening of a fragment library; (2) NMR-guided chemical optimization of the most promising fragments will be initiated. Together these studies present a first step toward the development of novel anti-HIV agents targeting CCR5 in the near term and CXCR4 in the long term. To our knowledge, the VLP-based approach toward drug discovery and optimization has not been pursued before and thus this application may be considered "High Risk". Nonetheless, the methodologies under development are expected to apply to GPCRs in general, which are the target of ~40% of all drugs, and thus this application presents the potential to have a very significant impact for human health. Together, we feel that the "High Risk" and "High Reward" aspects of the proposed research render it ideally suited for the R21 mechanism of support.