Understanding the dsRNA-IFN-antiviral immunity axis in rainbow trout

先天免疫反应是动物抵御入侵病毒的第一道防线，提供广谱的抗病毒保护。鱼类也不例外，事实上，刺激先天抗病毒免疫是开发新的抗病毒疗法以保护养殖鱼的极好方法，这对加拿大具有重要的经济意义。这项拟议的研究计划旨在调查三种尚未在一般鱼类和彩虹鲑鱼(安大略省最常见的养殖鱼)中发现的先天免疫反应。这项工作重点是双链(DS)RNA，由病毒在复制过程中产生，它是天然抗病毒免疫的基石-I型干扰素(IFN)的强大诱导剂。干扰素刺激干扰素刺激基因(ISGs)的产生，这些基因在细胞内积累，形成抗病毒状态，这是一种使细胞对病毒感染折射的保护状态。这一途径被称为dsRNA-干扰素-抗病毒轴。本提案的第一个目标将研究如何使用最近发现的一种自然方法来刺激dsRNA产生干扰素，即使用含有dsRNA的细胞外小泡。这种方法可能被证明是最佳的，因为它将保护dsRNA不被降解，并可能减少dsRNA的细胞毒作用。第二个目标将侧重于了解细胞内干扰素的影响，特别是两个ISG，VIG-1和VIG-3的功能。这些基因之所以令人感兴趣，是因为VIG-3本身和VIG-1活性的产物3‘-脱氧-3’，4‘-二氢-CTP(DdhCTP)可以被添加到细胞中以增强其固有的抗病毒活性。因此，了解这两个ISG的功能可能有助于开发新的抗病毒疗法，可以用来治疗鱼类的病毒感染。第三个目标将集中在训练有素的免疫上，这是对先天免疫系统的免疫记忆。抗病毒训练的免疫还不是很清楚；然而，如果适当地激活，它将允许幼年动物接受训练或记住病毒感染，以便它们在以后的生活中产生增强的抗病毒反应。训练有素的免疫的力量在于它提供了广谱的疫苗策略，因为训练有素的免疫力保护动物免受一般病毒的攻击，而不是传统疫苗对特定病毒株的保护。拟议的研究计划侧重于在dsRNA-干扰素-抗病毒轴中发现新的途径和反应，这不仅将提供基本的见解，而且将为在经济相关的鱼类中应用新的抗病毒疗法提供知识基础。

The innate immune response is the first line of defense against invading viruses in animals, and provides broad-spectrum antiviral protection. Fish are no exception, indeed stimulating innate antiviral immunity is an excellent approach to developing novel antiviral therapies to protect farmed fish, which are economically important for Canada. The proposed research program aims to investigate three innate immune responses that have yet to be identified in fish in general and rainbow trout (Ontario's most common farmed fish) specifically. This work focuses on double-stranded (ds)RNA, produced by viruses during replication, which is a strong inducer of the keystone of innate antiviral immunity, type I interferons (IFNs). IFNs stimulate the production of IFN-stimulated genes (ISGs) that accumulate within the cell to form the antiviral state, a protective state that makes a cell refractive to virus infection. This pathway is known as the dsRNA-IFN-antiviral axis. The first aim of the present proposal will examine how to stimulate interferon production with dsRNA using a natural' method just recently discovered, namely using extracellular vesicles containing dsRNA . This method may prove to be optimal, as it would protect dsRNA from degradation and may reduce dsRNA's cytotoxic effects. The second aim will focus on understanding interferon effects within the cell, specifically looking at the function of two ISGs, vig-1 and vig-3. These genes are of interest because vig-3 itself and the product of vig-1 activity, 3'-deoxy-3', 4'-didehydro-CTP (ddhCTP), can be added to cells to enhance their innate antiviral activity. Thus understanding the function of these two ISGs may help develop novel antiviral treatments that could be given to fish to treat virus infections. The third aim will focus on trained immunity, which is immunological memory of the innate immune system. Antiviral trained immunity is not well understood; however, if properly activated, it would allow for young animals to be trained' or remember virus infections in order for them to mount enhanced antiviral responses later in life. The power of trained immunity is that it provides broad-spectrum vaccine strategies, as trained immunity protects an animal against viruses in general, as opposed to traditional vaccines that provide protection to a specific strain of virus. The proposed research program focuses on discovering novel pathways and responses within the dsRNA-IFN-antiviral axis that will not only provide fundamental insights but the knowledge base for the application of novel antiviral therapies in an economically relevant fish species.