Dectin1/Syk信号通路减轻ARDS的机制研究

Acute respiratory distress syndrome (ARDS) is a common critical disease with high mortality. Pattern recognition receptors (PRRs) play an important role in excessive inflammatory reaction of ARDS. Our previous study discovered that Dectin-1, a member of PRRs, was highly expressed in ARDS. In the ARDS model, the lung injury of Dectin-1 knockout mice was more serious with higher mortality rate. Moreover, MyD88/NF-κB, the crucial downstream signaling molecules of TLR4, were greatly activated. These results suggest that Dectin-1 attenuates ARDS through the inhibition of TLR4 signaling pathway. Thus, we plan to explore the protective mechanism of Dectin-1 in ARDS via mass spectrometry, immunoprecipitation, RNA interference from 4 aspects: 1) The influence of Dectin-1 on the outcome of patients with ARDS; 2) verifying the protective effect of Dectin-1 in ARDS mouse model; 3) screening main effector cells; 4) identifying major molecular pathways and key proteins in Dectin-1/Syk pathway. The implementation of this project is expected to provide a new target and idea for the prevention and treatment of ARDS.

急性呼吸窘迫综合征(ARDS)是一种常见的危重症，病死率很高。模式识别受体（PRRs）在ARDS的过度炎症反应中发挥重要作用。本课题组前期研究发现：①PRRs的重要成员Dectin-1在ARDS模型中表达增高；②Dectin-1基因敲除小鼠肺损伤较野生型小鼠更重、死亡率更高、TLR4下游关键分子MyD88/NF-κB信号活化更强。以上结果提示，Dectin-1/Syk可通过调控TLR4通路实现对ARDS的保护作用。据此，本课题组拟利用质谱分析、免疫共沉淀、RNA干扰等技术手段，从4个层面开展研究：①探索Dectin-1对临床ARDS患者疾病转归的影响；②验证Dectin-1对ARDS模型小鼠的保护作用；③筛选Dectin-1保护ARDS的主要效应细胞；④明确Dectin-1/Syk起作用的主要分子通路及关键蛋白。本课题的实施有望为ARDS的防治提供新靶点和思路。

急性呼吸窘迫综合征(ARDS)是一种常见的危重症，病死率很高。模式识别受体（PRRs）在ARDS的过度炎症反应中发挥重要作用。本课题组根据前期研究：①PRRs的重要成员Dectin-1在ARDS模型中表达增高；②Dectin-1基因敲除小鼠肺损伤较野生型小鼠更重、死亡率更高、TLR4下游关键分子MyD88/NF-κB信号活化更强。提出Dectin-1/Syk可通过调控TLR4通路实现对ARDS的保护作用的假说。据此，本课题组从4个层面开展研究：①探索Dectin-1对临床ARDS患者疾病转归的影响；②验证Dectin-1对ARDS模型小鼠的保护作用；③筛选Dectin-1保护ARDS的主要效应细胞；④明确Dectin-1/Syk起作用的主要分子通路及关键蛋白。.通过GEO数据库发现现有生物学信息：Dectin-1和TLR4表达异常分别与ARDS成负相关和正相关关系；通过对 ARDS 患者血液等临床样本的检测结合病历资料Dectin-1 表达变化对ARDS 预后具有正相关性。.通过野生型与Dectin-1 基因敲除小鼠构建 ARDS 模型，提取肺组织HE染色，支气管肺泡灌洗液蛋白含量，肺干/湿，ELISA检测血清炎症因子含量，明确了Dectin-1 在 ARDS 中起保护作用。.对 ARDS 主要涉及的细胞进行功能分析，通过提取巨噬细胞、中性粒细胞、肺上皮细胞构建细胞脓毒症模型，经QPCR检测Dectin-1mRNA表达水平，明确了Dectin-1 对 ARDS 起保护作用的主要效应细胞是巨噬细胞。.提取肺泡巨噬细胞通过对Dectin-1过表达和干扰，经LPS刺激构建细胞脓毒症模型，利用 Q-PCR、 Western Blot、及ELISA明确Dectin-1的关键作用；通过免疫共沉淀获取内源性Syk，质谱分析Syk相互作用蛋白，揭示了 Dectin-1 抑制 TLR4 信号通路的关键分子机制，为 ARDS 的治疗提供新的靶点。