甲型H1N1流感病毒感染对小鼠肺损伤及肠道菌群的影响

目的 观察甲型H1N1流感病毒感染小鼠的一般状态、病毒载量、肺肠组织病理及肠道菌群的动态变化.方法 用流感病毒A/PR/8(H1N1)滴鼻感染C57BL/6J小鼠,留取感染后第3、7天肺和结肠组织以及感染第0、3、7天粪便,记算肺指数,测量结肠长度、重量,采用实时荧光定量PCR法检测肺组织病毒载量,HE染色观察肺、结肠...

Effects of influenza A (H1N1) virus infection on lung injury and gut microbiota in mice

  Objective  To investigate the dynamic changes of general status, lung tissue viral loads, pulmonary and intestinal histopathology and gut microbiota in mice infected with influenza A virus.  Methods  C57BL/6J mice were infected intranasally with influenza virus A/PR/8(H1N1). Lung and colon tissue of the mice were collected on day 3 and day 7 after infection. Stool samples of the mice were collected on day 0, 3 and 7 after infection. The lung indexes were calculated, and the lengths and weight of colon were measured. The viral loads in lung tissue were detected by real-time quantitative PCR (RT-qPCR). Pathological changes of lung and colon tissue were detected by HE staining. The micorbiota in the stool samples were sequenced by using the V3-V4 variable region of 16S rRNA.  Results  Compared with control group, the body weight and activities of mice in infection group decreased. On day 3 after the infection, compared with control group, the lung viral loads and lung index were significantly higher, the lung pathological injury occurred, and the colon length was shorter without remarkable colon pathology injury in the mice in infection group. On day 7 after infection, the lung viral loads in infected mice decreased compared with those on day 3 after infection. The lung index further increased, the lung pathological injury became more severe and the colon length further decreased compared with control group. No obvious colon pathology change (inflammation) was observed. On day 3 after infection, the abundance of Lactobacillus decreased in gut microbiota. On day 7 after infection, the abundance of Lactobacillus significantly decreased, the abundances of Shigella and Enterococcus remarkably increased in gut microbiota.  Conclusion  Mice infected with influenza A virus would exhibit weight loss, reduced intake, increased lung viral titers, lung pathological injury, shortened colon length, and gut microbiota alteration.