Portex Unit, University College London, Institute of Child Health, London.
Eur Respir J. 2014 Feb;43(2):485-96. doi: 10.1183/09031936.00205312. Epub 2013 Mar 21.
Respiratory syncytial virus is a major cause of respiratory disease. There are conflicting accounts of the response of human epithelial cells to respiratory syncytial virus and a lack of data on its effect on ciliary function. Our aim was to study the early stages of respiratory syncytial virus infection of primary human basal and ciliated cultures. Using high speed videomicroscopy, we found that ciliary beat frequency was unaffected by respiratory syncytial virus infection over 72 h; however, ciliary dyskinesia significantly increased within 24 h of infection (p<0.05). Transmission electron microscopy revealed that ultrastructural abnormalities were confined to ciliated cells, including increased cilia loss and mitochondrial damage. Confocal immunofluorescence microscopy showed that respiratory syncytial virus antigen gradually spread from the cell surface to the ciliary tip of infected cells over 3 days. Interestingly, ciliated cultures secreted fewer viruses than basal (progenitor) cell cultures and produced a chemokine response focused on recruitment of neutrophils. This study highlights differences in infection models and underscores the need to explore further the role of ciliated cells in the establishment of respiratory syncytial virus infection. Increased ciliary dyskinesia combined with ciliary loss and epithelial damage is likely to result in reduced mucociliary clearance early in the infective process.
呼吸道合胞病毒是呼吸道疾病的主要病因。关于人上皮细胞对呼吸道合胞病毒的反应存在矛盾的说法，并且关于其对纤毛功能影响的数据也缺乏。我们的目的是研究呼吸道合胞病毒感染原代人基底和纤毛培养物的早期阶段。使用高速视频显微镜，我们发现纤毛摆动频率在呼吸道合胞病毒感染 72 小时内不受影响；然而，纤毛运动障碍在感染后 24 小时内显著增加（p<0.05）。透射电子显微镜显示，超微结构异常仅限于纤毛细胞，包括纤毛丢失增加和线粒体损伤。共聚焦免疫荧光显微镜显示，呼吸道合胞病毒抗原在 3 天内逐渐从细胞表面扩散到感染细胞的纤毛尖端。有趣的是，纤毛培养物分泌的病毒比基底（祖细胞）培养物少，并且产生趋化因子反应，主要集中在招募中性粒细胞上。这项研究强调了感染模型的差异，并强调需要进一步探索纤毛细胞在呼吸道合胞病毒感染建立中的作用。纤毛运动障碍增加加上纤毛丢失和上皮损伤，可能导致感染过程早期黏液纤毛清除减少。
