Therapeutics targeting cathepsin-activated viral entry

描述(由申请人提供)：最近的证据表明，细胞组织蛋白在病毒糖蛋白加工和高致病性病毒埃博拉、SARS、冠状病毒和Nipah/Hendra的细胞进入中发挥重要作用。组织蛋白酶L似乎对SARS冠状病毒和尼帕病毒糖蛋白的激活很重要，而埃博拉病毒需要两种组织蛋白酶L和B才能进入病毒。这些酶的抑制剂有效地阻止病毒在细胞培养中的进入和复制。这项提案将建立在这些新发现的基础上，并将开发组织蛋白酶抑制剂作为这些不同病毒制剂的治疗药物。为了实现这一目标，我们提出了以下目标：具体目标1)利用高通量筛选不同的文库来鉴定组织酶抑制剂。具体目的2)使用携带埃博拉、SARS CoV或Hendra病毒糖蛋白的病毒假型，使用快速、定量和安全的方法测试候选化合物抑制病毒入侵。证实对SARS冠状病毒和一种模型冠状病毒--小鼠肝炎病毒(MHV)的复制有抑制作用。具体目标3)用SARS冠状病毒和MHV在动物模型系统中测试AIMS 1和AIMS 2中确定的组织蛋白酶抑制剂。总而言之，拟议的工作将产生用于治疗埃博拉、SARS冠状病毒和亨德拉等病毒感染的候选分子。

DESCRIPTION (provided by applicant): Recent evidence demonstrates an essential role for cellular cathepsins in viral glycoprotein processing and cellular entry for the highly pathogenic viruses Ebola, SARS, coronavirus and Nipah/Hendra. Cathepsin L appears to be important for SARS CoV and Nipah virus glycoprotein activation while Ebola requires both cathepsins L and B for viral entry. Inhibitors of these enzymes effectively block viral entry and replication in cell culture. This proposal will build upon these new findings and will develop cathepsin inhibitors as therapeutics for these diverse viral agents. To accomplish this goal we propose the following aims: Specific Aim 1) Utilize high throughput screening of diverse libraries to identify cathepsin inhibitors. Specific Aim 2) Test the candidate compounds for inhibition of viral entry using a rapid, quantitative and safe assay employing viral pseudotypes carrying the glycoproteins of Ebola, SARS CoV, or Hendra virus. Confirm the inhibitory effect on replication of SARS CoV and a model coronavirus, mouse hepatitis virus (MHV). Specific Aim 3) Test the cathepsin inhibitors identified in Aims 1 and 2 in animal model systems using SARS CoV and MHV. In conclusion, the proposed work will produce candidate molecules for treatment of infection by viruses such as Ebola, SARS CoV and Hendra.