RSV, Keratins and Distal Airway Infection

 描述(申请人提供)：呼吸道合胞病毒(RSV)是婴儿毛细支气管炎的主要原因。呼吸道合胞病毒(RSV)感染的人婴儿细支气管会被松弛的、RSV感染的上皮细胞堵塞，这些细胞与以中性粒细胞为主的炎性细胞浸润一起导致远端呼吸道的急性阻塞。我们的长期目标是了解为什么呼吸道合胞病毒有导致人类婴儿毛细支气管炎的如此倾向，并找到降低呼吸道合胞病毒远端呼吸道疾病严重程度的治疗方法。我们最近发现RSV非结构蛋白2(NS2)与RSV感染的柱状上皮细胞脱落有关，为RSV感染引起的上皮细胞脱落提供了直接证据。利用仓鼠作为呼吸道感染的活体模型，我们已经证明了RSV NS2促进的细胞脱落到远端细支气管腔导致脱落和病毒感染的上皮细胞的强劲聚集，从而堵塞和阻塞受感染的远端呼吸道。由于仓鼠呼吸道合胞病毒NS2表达的这些病理结果与人类呼吸道合胞病毒毛细支气管炎婴儿的组织病理学结果惊人地相似，我们认为RSV NS2是呼吸道合胞病毒感染时呼吸道远端细胞病理学和疾病的一个重要的病毒遗传决定因素。在这项试点和可行性研究中，我们专注于开发更好的模型，以进一步了解RSV NS2表达的后果，以使测试新的治疗方法来调节细胞脱落反应。我们还试图识别RSV NS2在远端呼吸道表达的新生物标记物，有助于在实验室和临床上确定新的治疗方法的有效性。改变对RSV NS2的细胞脱落反应的策略可能为降低RSV毛细支气管炎的发生率和严重性提供新的治疗方法。我们实现了三个独立但又相互关联的目标：具体目标1：RSV NS2表达在幼年仓鼠的远端呼吸道中的后果是否更持久和更严重？特定目的2.制备精密切片以研究RSV NS2在体外对细支气管呼吸道上皮细胞表达的影响。具体目的3：上皮角蛋白的RSV NS2修饰是否为远端呼吸道感染提供了新的生物标记物？通过实现这些目标，我们期望建立更好的模型来了解RSV NS2表达对远端呼吸道病理的影响，并寻找新的生物标志物来评估RSV感染过程中远端呼吸道上皮的受累情况。这些目标的成功完成将作为未来研究的基础，以确定减少RSV NS2表达后果的影响的策略。

 DESCRIPTION (provided by applicant): Respiratory Syncytial Virus (RSV) is the major cause of bronchiolitis in infants. Human infant bronchioles infected by RSV are commonly noted to be occluded by sloughed, RSV-infected epithelial cells which along with neutrophil-dominant inflammatory cell infiltrates contribute to acute obstruction of the distal airways. Our long term goals are to understand why RSV has such a propensity for causing bronchiolitis in human infants and to identify therapeutic approaches for reducing the severity of RSV distal airway disease. We have recently identified the RSV Non-Structural protein 2 (NS2) as being responsible for the shedding of RSV-infected columnar epithelial cells providing direct evidence that epithelial cell shedding may be a specific consequence of RSV infection. Using hamsters as an in vivo model of airway infection we have demonstrated RSV NS2-promoted cell shedding into the distal bronchiolar airway lumen results in robust accumulation of shed and virus-infected epithelial cells which clog and obstruct the infected distal airways. As these pathological consequences of RSV NS2 expression in hamster distal airways are strikingly similar to the histopathology obtained from human infants with RSV bronchiolitis we propose RSV NS2 is an important viral genetic determinant for distal airway cytopathology and disease during RSV infection. In this Pilot and Feasibility study, we focus on the development of better models for further understanding the consequences of RSV NS2 expression to enable testing of novel therapies to modulate the cell shedding response. We also attempt to identify novel biomarkers of RSV NS2 expression in the distal airways useful for determining efficacy of novel therapeutic approaches in the lab and in the clinic. Strategies to modify the cell shedding response to RSV NS2 may provide novel therapeutic approaches for reducing the incidence and severity of RSV bronchiolitis. We perform three independent but inter-related Aims: Specific Aim 1: Are the consequences of RSV NS2 expression more prolonged and severe in the distal airways of infant hamsters? Specific Aim 2. Generation of Precision Cut Lung Slices to investigate the impact of RSV NS2 expression in the bronchiolar airway epithelium ex vivo. Specific Aim 3. Does RSV NS2 modification of epithelial keratins provide novel biomarkers for distal airway infection? By performing these Aims we expect to generate better models for understanding the impact of RSV NS2 expression on distal airway pathology and identify novel biomarkers for assessing distal airway epithelium involvement during RSV infection. Successful completion of these Aims will serve as the foundation of future studies to identify strategies to reduce the impact of the consequences of RSV NS2 expression.