Project 1: Vimentin regulates host response and repair mechanisms to influenza A viral pneumonia

项目1 严重的病毒性肺炎，由于甲型流感病毒（IAV）破坏下呼吸道引起急性 呼吸窘迫综合征（ARDS）。急性呼吸窘迫综合征患者持续呼吸衰竭是一种 持续性炎症的后果和炎症消退的正常机制的失败， 肺组织修复对IAV的免疫应答中的关键步骤是NLRP 3炎性体的激活 以及随后分泌炎性细胞因子IL-1β和IL-18。 波形蛋白调节NLRP 3炎性体的形成和活化。我们建议通过暂时删除IAV感染小鼠病毒清除后单核细胞衍生的肺泡巨噬细胞（MoAM）中的波形蛋白来调节NLRP 3炎性体。 MoAM在免疫应答的启动和持续中起着至关重要的作用，限制了损伤的修复。 肺组织我们的数据显示，驱动炎症表型的基因在波形蛋白−/−中受到抑制， MoAM在诱导型条件性基因敲除小鼠中使用新的谱系追踪技术，我们将研究 波形蛋白是否通过促进MoAM中的炎症表型来调节持续性炎症， 清除IAV。调节性T细胞还通过抑制免疫应答， 反应和促进肺组织修复。我们的数据表明波形蛋白-/-Treg细胞表现出细胞- IAV感染后，其促修复功能的自主增加。我们假设有针对性的损失 肺泡巨噬细胞和调节性T细胞中的波形蛋白是促进促修复过程所必需的 严重的IAV感染。 具体目标1。为了确定波形蛋白在单核细胞源性肺泡上皮细胞中的靶向丢失是否是 巨噬细胞抑制它们的炎症反应，并促进严重肺损伤后的肺修复。 流感感染。我们建议通过以下方法破坏持续性炎症，这种炎症限制了受损肺组织的修复： IAV中病毒清除后单核细胞衍生的肺泡巨噬细胞中波形蛋白的时间控制缺失- 感染的老鼠 具体目标2。确定波形蛋白中间丝的解聚是否导致 代谢重编程以抑制肺泡巨噬细胞炎性表型。我们的初步 数据表明，从炎症巨噬细胞表型到促修复巨噬细胞表型的转变与代谢相关， 波形蛋白中间丝的重编程和解聚。 具体目标3。为了确定波形蛋白的暂时的、细胞特异性的缺失是否增强了前修复， 调节性T细胞在从IAV诱导的肺炎中恢复期间的功能。我们建议确定 波形蛋白-/-Treg细胞是否通过增加细胞自主修复功能来增强其功能， 流感病毒感染后腺苷信号传导和双调蛋白的产生。

PROJECT SUMMARY PROJECT 1 Severe viral pneumonia, due to influenza A virus (IAV) damages the lower respiratory tract to cause acute respiratory distress syndrome (ARDS). The persistence of respiratory failure in patients with ARDS is a consequence of persistent inflammation and the failure of normal mechanisms of inflammation resolution and lung tissue repair. A crucial step in the immune response to IAV is the activation of the NLRP3 inflammasome and subsequent secretion of inflammatory cytokines, IL-1β and IL-18. Vimentin regulates the formation and activation of the NLRP3 inflammasome. We propose to modulate the NLRP3 inflammasome by temporally deleting vimentin in monocyte-derived alveolar macrophages (MoAMs) post-viral clearance in IAV-infected mice. MoAMs play crucial roles in both initiation and continuation of the immune response, limiting repair of the injured lung tissue. Our data revealed that genes driving the inflammatory phenotype are suppressed in Vimentin−/− MoAMs. Using novel lineage-tracing techniques in inducible conditional knockout mice, we will investigate whether vimentin regulates persistent inflammation by promoting an inflammatory phenotype in MoAMs following clearance of IAV. Regulatory T cells also contribute to recovery from viral pneumonia by suppressing immune responses and promoting lung tissue repair. Our data suggest that Vimentin−/− Treg cells exhibit a cell- autonomous increase in their pro-repair function following IAV infection. We hypothesize that a targeted loss of vimentin in alveolar macrophages and regulatory T cells is required to promote pro-repair processes following severe IAV infection. Specific Aim 1. To determine whether a targeted loss of vimentin in monocyte-derived alveolar macrophages suppresses their inflammatory response and promotes lung repair following severe influenza infection. We propose to disrupt the persistent inflammation that limits repair of injured lung tissue by temporally-controlled deletion of vimentin in monocyte-derived alveolar macrophages post-viral clearance in IAV- infected mice. Specific Aim 2. To determine whether depolymerization of vimentin intermediate filaments causes metabolic reprogramming to suppress alveolar macrophage inflammatory phenotype. Our preliminary data suggest that a switch from inflammatory to pro-repair macrophage phenotype is associated with metabolic reprogramming and depolymerization of vimentin intermediate filaments. Specific Aim 3. To determine whether temporal, cell-specific loss of vimentin augments the pro-repair function of regulatory T cells during recovery from IAV-induced pneumonia. We propose to determine whether Vimentin−/− Treg cells exhibit their augmented cell-autonomous pro-repair function via increased adenosine signaling and amphiregulin production following influenza A virus infection.