Understanding Human B Cell Responses to Influenza to Improve the Influenza

我们有令人信服的新数据表明，在不同情况下提供流感疫苗可以诱导B细胞对流感的长期记忆发生巨大变化。这一重要的概念证明表明，人类B细胞反应可以根据需要重新训练，以提高疫苗效力。在这个项目中，我们将探索这些观察的机制。收集到的原则对于开发改进的流感疫苗非常重要。首先，在Aim 1中，我们将探索B细胞记忆和免疫血清在重新暴露于变异流感病毒株时对特定表位的抗体反应重定向中的作用。其次，在目标2中，我们将确定是否像对血凝素的反应一样，在首次暴露于2009年流感大流行毒株时，广泛交叉反应的B细胞的优势被激活以对抗神经氨酸酶。我们还将使用新的方法来确定先前观察到的偏倚流感表位靶向在人群中的稳定性。最后，我们已经确定了我们认为是“流行病记忆”的B细胞分化，我们假设它会持续数月而不是永久地保持高数量，并提供即时保护，因为在流行病期间极有可能再次暴露。我们相信，这些记忆细胞，当用相关或不相关的毒株接种疫苗诱导时，可以在不久的将来以原始抗原（OAS）的方式显著影响对变异流感毒株的反应。事实上，这些细胞可能解释了我们观察到的一些但不是所有队列成员的戏剧性变化，导致反应更广泛或更菌株特异性的反应。我们将探讨这些细胞的表型和功能。此外，通过确定来自该人群的B细胞的特异性，我们将直接确定这些记忆细胞在再次暴露于不同流感毒株时的影响。了解B细胞记忆的类型和阶段将有助于更好地靶向流感疫苗反应。最后，在这些研究的背景下，我们将开发新的技术，如我们的“表位阴影”方法，使用我们新的单抗微阵列平台，允许快速和全局筛选单克隆和多克隆（血清）表位靶向。我们还将制作一大批抗流感的人单克隆抗体。这些抗体可以识别对开发广泛保护性疫苗很重要的表位，或者单克隆抗体本身可能具有治疗潜力。

We have compelling new data demonstrating that providing the influenza vaccine in different contexts can induce dramatic shifts in long-term B cell memory to influenza. This important proof of concept suggests that human B cell responses can be re-trained as needed to improve vaccine efficacy. In this project we will explore the mechanism of these observations. The principles gleaned will be important in the development of an improved influenza vaccine. First, in Aim 1, we will explore the role of B cell memory and immune sera in redirecting antibody responses to particular epitopes upon re-exposure to variant influenza strains. Secondly, in Aim 2 we will determine if, like the response to hemagglutinin, a predominance of broadly cross-reactive B cells were activated against neuraminidase upon first exposure to the 2009 pandemic strain of influenza. We will also use novel approaches to determine how stable previously observed biased influenza epitope targeting in human populations is. Finally, we have identified what we believe is an "epidemic-memory" B cell differentiation that we hypothesize persists at high numbers for months rather than permanently, and provides immediate protection due to the highly likely re-exposure that will occur during an epidemic. We believe that these memory cells, when induced by vaccination with relevant or irrelevant strains, can substantially impact responses to variant influenza strains occurring in the near future in an original-antigenic sin (OAS) fashion. In fact, these cells may account for the dramatic shifts that we observed for some but not all members of our cohort, leading to responses with either greater breadth or more strain-specific responses. We will explore the phenotype and function of these cells. Further, by determining the specificity of the B cells from this population we will directly determine the impact of these memory cells upon re-exposure to a divergent influenza strain. Understanding the types and stages of B cell memory will allow better targeting of the influenza vaccine response. Finally, in the context of these studies we will develop new technologies such as our "epitope-shadowing" approach using our novel mAb microarray platform to allow rapid and global screening of both monoclonal and polyclonal (serum) epitope targeting. We will also generate a large panel of human mAbs against influenza. These antibodies may identify epitopes important for developing a broadly protective vaccine or the mAbs themselves may have therapeutic potential.