Discovery and Analysis of Synthetic TLR Agonists and Antagonists

描述（由申请人提供）：toll样受体（TLRs）很重要，因为它们介导感染的初始意识，因为它们引发已知最强大的炎症反应。激动剂和拮抗剂均可用于临床目的。然而，对于tlr是如何被触发产生不同的信号，或者激动剂和拮抗剂结构的“规则”是什么，人们知之甚少。我们建议在合成化学家和TLR生物学家之间进行合作，以鉴定和表征TLR的新的和固有的信息配体。Boger实验室使用液相合成技术生产了一个全面的肽模拟分子文库，专门用于探测、模拟和破坏各种类型的蛋白质-蛋白质相互作用。Beutler实验室筛选了该文库（95,000个化合物）中的TLR激动剂。在一个信息丰富且全面的a-螺旋模拟子库中，几个非常强大且结构相关的hit揭示了一类新的TLR4激动剂。对种系突变小鼠反应的研究表明，与LPS （TLR4的天然配体）不同，这些分子发出信号诱导NF-？B依赖性细胞因子TNF，而不是I型ifn。构效关系（SAR）分析已经开始揭示这些配体的激动剂活性的结构规律，这些配体的构象类似于具有a-螺旋二级结构的七聚肽。将继续对正在进行的新图书馆进行筛选，以确定“转”、“表”和“表”。具有激动剂和拮抗剂性质的-旋肽类配体。一旦发现这些分子，将对其进行SAR分析，优化其活性，并利用Beutler实验室生产和维持的TLR信号突变体，对其对TLR信号的影响进行详细研究。这些分子与tlr或相关蛋白之间的相互作用位点将使用光亲和标记方法进行定位。在适当的情况下，配体将与其同源受体共结晶，以进行高分辨率结构分析。这些分子的性质（药代动力学、毒性、免疫佐剂作用和保护宿主免受模型感染的能力）也将在体内进行分析。

DESCRIPTION (provided by applicant): The Toll-like receptors (TLRs) are important both because they mediate initial awareness of infection and because they elicit the most powerful inflammatory responses known. Both agonists and antagonists might be used for clinical purposes. Yet there is little understanding of how TLRs are triggered to yield qualitatively distinct signals, or what the "rules" for agonist and antagonist structure might be. We propose a collaboration between synthetic chemists and TLR biologists to identify and characterize new and inherently informative ligands for TLRs. The Boger lab has used solution-phase synthesis to produce a comprehensive library of peptide mimetic molecules, specifically designed to probe, mimic, and disrupt various types of protein-protein interactions. The Beutler lab has screened this library (95,000 compounds) for TLR agonists. Within an information-rich and comprehensive a-helix mimetic sub-library, several remarkably robust and structurally related hits have revealed a new class of TLR4 agonists. Studies of responses in germline mutant mice have shown that unlike LPS (the natural ligand for TLR4), these molecules signal to induce the NF-?B dependent cytokine TNF, but not type I IFNs. Structure-activity relationship (SAR) analyses have begun to reveal structural rules for agonist activity by these ligands, which conformationally resemble heptameric peptides with a-helical secondary structure. Continued screening of new libraries that are in progress will be performed to identify ¿-turn, ¿-sheet, and ?-turn peptidomimetic ligands with both agonist and antagonist properties. As they are discovered, these molecules will be subjected to SAR analysis, optimized for activity, and detailed studies of their effects on TLR signaling will be undertaken using TLR signaling mutants produced and maintained in the Beutler lab. The sites of interaction between these molecules and TLRs or associated proteins will be mapped using photoaffinity labeling methods. Where appropriate, the ligands will be co-crystallized with their cognate receptors for high resolution structural analysis. The properties of the molecules (pharmacokinetics, toxicity, immunoadjuvant effects, and ability to protect the host from model infections) will also be analyzed in vivo.