Role of CCR1 in Cytokine Storm & Immunopathology after influenza infection

感染高致病性流感病毒（包括禽流感H5N1病毒和1918年H1N1病毒）后的死亡率与这些病毒诱导严重尼古丁介导的免疫病理学的倾向有关，其特征为低氧血症和肺出血性炎性水肿。此外，急性促炎性细胞因子的产生与甲型流感病毒感染儿童中致命性流感相关脑病的发生相关。抗病毒神经氨酸酶抑制剂能够 控制病毒感染，如果早期给予病人，但没有药物已被报道是有效的治疗苦参碱介导的肺损伤。重要的是，流感感染期间致病性细胞因子的确切来源尚未确定。然而，肺中单核细胞来源的细胞的积累与几种炎性肺病中肺损伤的发展相关，并且这些细胞已经在肺中积累。 提示流感病毒感染后炎性细胞因子的主要来源。流感病毒感染后炎性骨髓细胞向肺部的募集、分化和活化的机制仍然难以捉摸。趋化因子受体CCR1由造血细胞（包括单核细胞、巨噬细胞和DC）和一些非骨髓来源的细胞表达。我们的初步数据表明，CCR1缺失保护免受致命的流感感染相关的免疫病理学和死亡率。基于 根据我们的初步结果，我们假设CCR1缺陷通过阻止感染肺内单核细胞源性炎症细胞的激活来预防流感相关死亡率。在本提案中，我们将确定CCR1缺陷如何促进保护免受与致病性流感感染相关的免疫病理学（目的1），并将评估CCR1拮抗剂在治疗流感相关免疫病理学（目的2）中的潜在治疗用途。

Mortality after infection with highly pathogenic influenza viruses, including avian H5N1 virus and the 1918 H1N1 virus, is associated with the propensity of these viruses to induce severe cytokine-mediated immunepathology, characterized by hypoxemia and hemorrhagic inflammatory edema in the lung. In addition, acute pro-inflammatory cytokine production has been correlated with the onset of fatal influenza-associated encephalopathy in children infected with influenza A viruses. Antiviral neuraminidase inhibitors are able to control viral infection if given early to patients, but no drugs have been reported to be effective in treating the cytokine-mediated lung damage. Importantly, the exact source of pathogenic cytokines during influenza infection has been not identified. However, accumulation of monocyte-derived cells in the lungs is associated with the development of lung damage in several inflammatory pulmonary diseases, and these cells have been suggested the major source of inflammatory cytokines after influenza infection. Mechanisms orchestrating the recruitment, differentiation and activation of inflammatory myeloid cells to the lung following flu infection remain elusive. The chemokine receptor CCR1 is expressed by hematopoietic cells, including monocytes, macrophages and DCs, and by some non-bone marrow-derived cells. Our preliminary data demonstrate that CCR1 deletion protects from lethal influenza infection associated immunopathology and mortality. Based on our preliminary results, we hypothesize that CCR1 deficiency prevents influenza-associated mortality by preventing activation of monocyte-derived inflammatory cells within the infected lungs. In this proposal, we will determine how CCR1 deficiency promotes protection from the immunopathology associated with pathogenic influenza infections (Aim 1) and will evaluate the potential therapeutic uses of CCR1 antagonists in treating influenza-associated immunopathology (Aim 2).