Targeting natural killer cells to enhance HIV vaccine responses

少年派：斯蒂芬·诺尔的瓦格纳，“以自然杀伤细胞为靶点，增强艾滋病毒疫苗的反应” 摘要 免疫接种是人类历史上最成功的公共卫生干预措施之一，预防 每年有200多万人死亡。大多数获得许可的疫苗都是通过诱导抗体来预防 通过中和入侵的病原体而感染。然而，疫苗介导的广泛中和诱导 能够阻止感染像艾滋病毒这样高度变异的病原体的抗体已经被证明是异常的 在人类和动物模型中都是困难的。疫苗成功的这一缺陷很可能是由于固有免疫。 限制免疫反应数量和质量的调节机制。翻译学的发展 克服这些免疫障碍的方法为下一代的进步带来了巨大的希望 预防感染和改善全球健康的疫苗。 我们的研究重点是自然杀伤(NK)细胞抑制T和B细胞反应的非凡能力。 NK细胞限制免疫后触发的获得性免疫记忆的大小和质量。本练习 NK细胞通过限制体细胞突变影响保护性中和抗体的产生 以及这些抗体在生发中心内的亲和力成熟。我们发现转录上的一个子集 独特的NK细胞在免疫后迁移到生发中心形成的部位，并有助于 穿孔素介导的活化CD4T消除抑制滤泡辅助性T细胞分化 细胞。我们确定了关键的效应分子、受体和转录因子，这些都可能对此至关重要。 NK细胞的免疫抑制活性，因此是提高疫苗效力的创新靶点。 这项提案的总体目标是测试科学前提，即NK细胞的细胞毒功能限制 疫苗介导的艾滋病毒特异性广谱中和抗体的产生。我们分三个主题提出 相互关联的目标，探索决定细胞毒性的各种介质的作用 免疫过程中NK细胞的免疫调节能力。在目标1中，我们将使用尖端的敲入鼠标来 检验免疫期间对NK细胞杀伤功能的一过性小分子抑制可以 安全有效地增强生发中心介导的HIV特异性抗体反应的成熟。在AIM 2，我们将使用创新的骨髓嵌合体和条件性基因敲除小鼠来定义 转录因子、趋化因子受体和整合素在Tfh-TO发育期NK细胞定位中的作用 促进这些靶细胞的细胞溶解。在目标3中，我们将使用一种新的小鼠品系，并开创基于CRISPR的 筛选参与促进或抑制NK细胞对CD4T细胞杀伤的受体。这些 实验将定义能够实现和校准适应性免疫反应的NK细胞抑制的因素 在感染期间。因此，拟议的工作将有助于随后开发和部署创新的 提高艾滋病毒疫苗效力的战略。

PI: Waggoner, Stephen Noel, “Targeting natural killer cells to enhance HIV vaccine responses” ABSTRACT Immunization represents one of the most successful public health interventions in human history, preventing more than 2 million deaths each year. Most licensed vaccines work by eliciting antibodies that can prevent infection by neutralizing the invading pathogen. However, vaccine-mediated induction of broadly neutralizing antibodies capable of thwarting infection with a highly mutable pathogen like HIV has proven exceptionally difficult in both humans and animal models. This shortcoming in vaccine success is likely due to intrinsic immune regulatory mechanisms that limit the quantity and quality of immune responses. Development of translational means to overcome these immunological roadblocks holds great promise for advancement of next-generation vaccines to prevent infection and improve global health. Our research focuses on the remarkable capacity of natural killer (NK) cells to suppress T and B cell responses. NK cells limit the magnitude and quality of adaptive immune memory triggered after immunization. This activity of NK cells impairs the generation of protective neutralizing antibody responses by restricting somatic mutation and affinity maturation of these antibodies within germinal centers. We find that a subset of transcriptionally unique NK cells migrates to sites of germinal center formation following immunization and contributes to suppression of follicular helper T cells (Tfh) differentiation via perforin-mediated elimination of activated CD4 T cells. We identify key effector molecules, receptors, and transcription factors that are putatively vital for this immunosuppressive activity of NK cells, and therefore represent innovative targets to enhance vaccine efficacy. The overall objective of this proposal is to test the scientific premise that cytotoxic functions of NK cells limit vaccine-mediated generation of HIV-specific broadly neutralizing antibodies. We propose three thematically connected aims that explore the contributions of various mediators that determine the cytotoxic immunoregulatory capacity of NK cells during immunization. In Aim 1, we will use cutting-edge knock-in mice to test the hypothesis that transient small molecule inhibition of NK-cell cytolytic function during immunization can safely and effective augment germinal center-mediated maturation of HIV-specific antibody responses. In Aim 2, we will use innovative bone marrow chimera and conditional knock-out mice to define the role of a network of transcription factors, chemokine receptors, and integrins in localization of NK cells near developing Tfh to facilitate cytolysis of these target cells. In Aim 3, we will use a new strain of mice and pioneering CRISPR-based screens to discover receptors involved in promotion or restraint of NK-cell killing of CD4 T cells. These experiments will define factors that enable and calibrate NK-cell suppression of adaptive immune responses during infection. Thus, the proposed work will facilitate subsequent development and deployment of innovative strategies to enhance HIV vaccine efficacy.