Toward a Universal Influenza Virus Vaccine

描述（由申请方提供）：抗流感病毒的广谱疫苗的开发将对现有的抗流感药物做出巨大贡献。最近的研究表明存在广泛中和的抗流感抗体，并首次表明，病毒血凝素的区域可以介导针对流感病毒的广泛免疫。现在的挑战是开发一种基于这些区域的疫苗，以增强人类的广谱免疫力。在这个建议中，我们描绘了一个实验的方法走向发展的通用流感病毒疫苗。基本策略是鉴定介导广泛病毒中和的血凝素的表位，随后将这些表位掺入新的免疫原中，最后通过添加将使用人离体实验系统鉴定的佐剂组分来增强和增加免疫原。我们将在小鼠和雪貂疾病模型中测试免疫原和佐剂制剂。我们在本提案中概述的策略是通过在鉴定广泛中和抗体和生产中的大量初步实验来开发和完善的。 广谱流感疫苗的原型。我们自己的初步研究，沿着与合作研究人员的综合专业知识，支持这项拟议工作的可行性。我们坚信，我们在这一领域的持续努力有可能产生一种提供广谱保护的流感疫苗，这种保护比现有疫苗提供的保护强得多。 相关性：这项工作的目的是产生广泛保护性的流感病毒疫苗，并研究人类对流感病毒的免疫力。本文概述的实验方法是在初步实验中开发和完善的，在这些实验中，我们鉴定了广泛中和抗体，并生成了原型流感免疫原，旨在提供比当前疫苗更高的广谱覆盖率。我们的初步研究沿着其他小组的工作证明了广谱流感病毒疫苗的概念验证，并证明了在疫苗设计这一领域的主要努力是合理的。 项目1：基于流感病毒血凝素保守表位的新型免疫原设计 项目负责人：Palese，P. 描述（由申请方提供）：拟定工作是生产广泛保护性流感病毒疫苗。我们将用于实现疫苗生成目标的基本实验方法分为两个阶段。目的1是鉴定对不同流感病毒株的血凝素具有广泛保护活性的人和鼠单克隆抗体。将努力确定这些广泛保护性抗体在血凝素分子上结合的精确区域。这项工作的目标2将涉及新的疫苗构建体的设计和生产，这些疫苗构建体将免疫力集中在那些确定介导广泛保护的表位上。我们将构建一组新的免疫原：几个将基于保守的，连续的，多肽区域的血凝素，其他人是基于构象，不连续的部分或嵌合血凝素。疫苗接种策略将涉及使用DNA、重组纯化蛋白或纯化（嵌合）病毒。与项目2和3合作，将通过使用补充佐剂制剂优化疫苗构建体，并将在小鼠和雪貂疾病模型中评价其有效性。 相关性：目前的流感病毒疫苗必须每年新生产，因为流行的流感病毒株在不断变化。我们正在尝试设计新型通用流感病毒疫苗，其将对不同毒株具有交叉保护性，从而持续更长时间，避免每年重新接种的必要性;这将通过首先鉴定交叉保护性单克隆抗体（针对病毒血凝素）和它们识别的精确表位/序列来完成。然后，这些表位将用于指导疫苗构建体的设计，所述疫苗构建体诱导针对许多不同流感病毒变体的交叉保护性免疫应答。

DESCRIPTION (provided by applicant): The development of a broad-spectrum vaccine against influenza viruses would represent a tremendous contribution to the available armamentarium against influenza. Recent studies demonstrate the existence of broadly neutralizing anti-influenza antibodies and show, for the first time, that there are regions of the viral hemagglutinin that can mediate broad immunity against influenza viruses. The challenge, now, is to develop a vaccine based on these regions that elicits broad-spectrum immunity in humans. In this proposal, we delineate an experimental approach toward the development of a universal influenza virus vaccine. The basic strategy is to identify epitopes of the hemagglutinin that mediate broad virus neutralization, to subsequently incorporate those epitopes into novel immunogens, and finally to enhance and augment the immunogens by addition of adjuvanting components that will be identified using a human ex vivo experimental system. We will test immunogens and adjuvant preparations in mice and in ferret models of disease. The strategy that we outline in this proposal was developed and refined by way of substantial preliminary experimentation both in the identification of broadly neutralizing antibodies and in the production of prototype broad-spectrum influenza vaccines. Our own preliminary studies, along with the combined expertise of the collaborating investigators, support the feasibility of this proposed work. We strongly believe that our continued efforts in this area are likely to result in an influenza vaccine that provides broad-spectrum protection that is much enhanced over that provided by currently available vaccines. RELEVANCE: The purpose of this proposed work is to generate broadly-protective influenza virus vaccines and to study human immunity to influenza viruses. The experimental approach outlined here was developed and refined during preliminary experiments in which we identified broadly neutralizing antibodies and generated prototype influenza immunogens designed to provide enhanced broad-spectrum coverage over current vaccines. Our preliminary studies along with work from other groups demonstrate proof-of-concept for broad-spectrum influenza virus vaccines and justify major efforts in this area of vaccine design. Project 1: Design of New Immunogens Based on Conserved Epitopes in the Influenza Virus Hemagglutinin Project Leader: Palese, P. DESCRIPTION (provided by applicant): The proposed work is to generate broadly-protective influenza virus vaccines. The basic experimental approach that we will use to accomplish the goal of vaccine generation is divided into two phases. Aim 1 involves characterization of human and murine monoclonal antibodies with broad protective activity against hemagglutinins of distinct influenza virus strains. Efforts will be made to determine the precise region of binding o these broadly-protective antibodies on the hemagglutinin molecule. Aim 2 of this work will involve the design and production of novel vaccine constructs that focus immunity towards those epitopes determined to mediate broad protection. We will construct a set of novel immunogens: several will be based on conserved, continuous, polypeptidic regions of the hemagglutinin, others are based on conformational, discontinuous moieties or on chimeric hemagglutinins. The vaccination strategies will involve the use of DNA, recombinantly purified protein or purified (chimeric) virus. In collaboration with Projects 2 and 3, the vaccine construct will be optimized by use of complementary adjuvant preparations and will be evaluated for efficacy in both mouse and in ferret models of disease. RELEVANCE: Present influenza virus vaccines have to be newly manufactured every year because the circulating influenza virus strains are continuously changing. We are attempting to design novel universal influenza virus vaccines which would be cross-protective against different strains and thus last longer, avoiding the necessity of annual revaccinations; this will e done by first identifying cross-protective monoclonal antibodies (directed against the viral hemagglutinin) and the precise epitopes/sequences they recognize. These epitopes will then be used to guide the design of vaccine constructs which induce cross-protective immune responses against many different influenza virus variants.