Systemic coordination of pro-inflammatory immune reactions through dendritic cell-restricted sIL6R biogenesis

项目摘要/摘要 这是助理教授Daniel Lingwood博士(PI)和Alejandro Balazs博士(Co-I)的申请 哈佛医学院和麻省理工学院、麻省理工学院和哈佛大学拉贡研究所的教职员工。他们的 实验室专门定义对疫苗的抗体反应的免疫学(林伍德)和 通过AAV介导的基因传递进行免疫工程(Balazs)。林伍德博士发现 对接种疫苗的抗体反应，以及一般的促炎免疫反应，都受到中央调节。 通过由传统树突状细胞(CDC)提供的新控制轴，在小鼠中定义了单一的淋巴系 通过转录因子Zbtbt46的表达。林伍德博士发现，疾病预防控制中心负责 可溶性循环形式的IL-6受体(SIL6R)的体内生物发生，它通常从 系统地协调其信令活动的解决方案。IL-6是一种释放的强有力的促炎细胞因子 在免疫攻击或组织损伤后，sIL6R对其捕获的失调会导致 高生理性IL-6水平与炎症性疾病。这一提议将检验核心假设，即 CDC对sIL6R的生物合成形成一个可调节增强免疫的集中控制轴 在疾病状态下防御和恢复IL-6的稳态。在目标1中，林伍德博士将定义 CDC细胞表面金属蛋白酶ADAM10和ADAM17对系统sIL6R的释放。这些 蛋白酶切割表面IL6R以从组织培养细胞系中剥离sIL6R，增强可药物靶点 调节IL-6免疫效应。然而，ADAM10/17基因敲除是胚胎致死的，防止了机械性 对其体内活性进行评价。林伍德博士现在选择性地指导了ADAM10和/或ADAM17 并将使用这些转基因动物来定义两个CDC内的ADAM活性- 依赖参数：循环中sIL6R的设定点和免疫攻击后sIL6R生物生成的诱导。 Lingwood博士还发现CDC衍生的sIL6R，以及随后通过 SIL6R：IL-6复合体，是B细胞向分泌抗体的浆细胞分化所必需的 用多种蛋白疫苗抗原免疫后产生抗体。在《目标2》中，林伍德博士将 定义CDC来源的sIL6R如何通过这一途径将先天免疫和适应性免疫联系起来(传统的 CDC的T细胞启动活性)，以及更具体地说，如何将其作为一种天然佐剂原理加以利用 提高流感疫苗的效力。在AIM 3中，Lingwood博士和Balazs博士开发了一种AAV- 修复体内sIL6R水平及其IL-6捕获活性的基因传递平台。他们将使用这个系统 通过实验确定sIL6R内致病基因的多态如何失调IL-6捕获和 体内炎症活动，然后并行，治疗性sIL6R表达水平需要纠正IL-6 体内平衡和恢复其中的功能。总的来说，这项提案将定义和利用新发现的 用于治疗人类疾病的sIL6R免疫防御生物学，与美国国立卫生研究院的目标和使命一致。

Project Summary / Abstract This is an application by Dr. Daniel Lingwood (PI), and Dr. Alejandro Balazs (Co-I), Assistant Professors at Harvard Medical School and faculty members of the Ragon Institute of MGH, MIT and Harvard. Their laboratories specialize in defining the immunology of antibody responses to vaccines (Lingwood) and in the engineering of immunity through AAV-mediated gene delivery (Balazs). Dr. Lingwood has discovered that antibody responses to vaccination, and pro-inflammatory immune reactions generally, are centrally regulated by novel control axis supplied by conventional dendritic cells (cDC), a single lymphoid lineage defined in mice by expression of the transcription factor Zbtbt46. Dr. Lingwood has found that cDCs are responsible for the in vivo biogenesis of the soluble, circulating form of the IL-6 receptor (sIL6R), which normally captures IL-6 from solution to systemically coordinate its signaling activity. IL-6 is a potent pro-inflammatory cytokine released following immune challenge or tissue injury, and dysregulation of its capture by sIL6R leads to hyperphysiologic IL-6 levels and inflammatory disease. This proposal will test the central hypothesis that biogenesis of sIL6R by cDC forms a centralized control axis that can be modulated to enhance immune defense and restore IL-6 homoeostasis in disease states. In Aim 1, Dr. Lingwood will define the contribution of the metalloproteases ADAM10 and ADAM17 to systemic sIL6R release from the cDC cell surface. These proteases cleave surface IL6R to shed sIL6R from tissue culture cells lines, potentiating a drugable target to modulate IL-6 immune effects. However, ADAM10/17 knockouts are embryonic lethal, preventing mechanistic evaluation of their activity in vivo. Dr. Lingwood has now selectively directed ADAM10 and/or ADAM17 knockouts to the cDC lineage and will use these transgenic animals to define ADAM activity within two cDC- dependent parameters: circulating sIL6R set-point and induction of sIL6R biogenesis after immune challenge. Dr. Lingwood has also discovered that cDC-derived sIL6R, and subsequent trans IL-6 signaling through the sIL6R:IL-6 complex, is necessary for B cell differentiation to antibody secreting plasma cells, and tunes antibody output following immunization with a variety of protein vaccine antigens. In Aim 2, Dr. Lingwood will define how cDC-derived sIL6R links innate and adaptive immunity through this pathway (outside the traditional T cell priming activity of cDC), and more specifically how this can be harnessed as a natural adjuvant principle to improve the efficacy of influenza vaccines. In Aim 3, Dr. Lingwood and Dr. Balazs have developed a AAV- gene delivery platform that rescues sIL6R levels and its IL-6 capture activity in vivo. They will use this system to experimentally define how disease-causing polymorphisms within sIL6R dysregulate IL-6 capture and inflammatory activity in vivo, and then in parallel, the therapeutic sIL6R expression level needed to correct IL-6 homeostasis and restore function therein. Collectively, this proposal will define and exploit newly discovered biology of sIL6R immune-defense to treat human disease, consistent with the goals and mission of the NIH.