免疫跨膜蛋白TLR3是当前备受关注的抗动脉粥样硬化（AS）药物新靶标，该类药物的主要瓶颈是抑制剂非常有限且亚型选择性低。因而，发现、设计高选择性抑制剂已成为AS及相关免疫疾病研究亟待解决的关键问题。我们近期通过基于细胞（过表达TLR3）的筛选办法，从2万个化合物中发现了一类吲哚并异喹啉天然产物，具备骨架结构新颖、体外选择性抑制TLR3、体内抗AS的特点。本项目拟在已有基础上，定向TLR3/dsRNA关键残基，使用多种药物设计方法，设计合成出系列新型吲哚异喹啉类化合物；综合其在HEK-TLR过表达细胞中对TLR各亚型的选择性、TLR3抑制效应、ApoE-/-基因敲除小鼠体内抗AS药效和初步安全性等性质，优化出2-3个先导结构；开展先导结构与靶标的相互作用研究，通过点突变揭示影响抑制活性的关键残基，并阐明TLR3识别选择性抑制剂的分子机制，为TLR3高选择性抑制剂的设计提供充分的科学依据。

Transmembrane protein TLR3 is a new target of anti-atherosclerosis (AS) drugs, but the bottleneck of this kind of drugs is that the inhibitors are limited and also with low selectivity. Therefore, the discovery and design of highly selective inhibitors have become the key problems which need to be solved urgently in AS and related immune diseases. By targeting TLR3/dsRNA interactions and using cell based screening of 20,000 compounds, we recently found a class of indole-isoquinoline polycyclic natural products with advantage of novel structure skeleton, selective inhibition of TLR3 in vitro and anti-AS in vivo. As a continue of our existing work, a series of novel indole-isoquinoline compounds were designed and synthesized by using various drug design methods for the key residues of TLR3/dsRNA. In view of their selectivity, activity in HEK-TLR cell lines, and anti-AS efficacy in ApoE-/- gene knockout mice, as well as preliminary safety properties, 2-3 lead structures will be selected. The interaction between the lead structures and target also will be evaluated to disclose the key residues and reveal the bioactivity by means of mutation and bioassay. This project will elucidate the molecular mechanism of TLR3 selective inhibitor recognition, and provide more adequate scientific basis for the design of high selective TLR3 inhibitors, also offer a useful basis for clinical drug development.