title: Acute lung injury induced by H9N2 virus in mice.
abstract: BACKGROUND
  H9N2 avian influenza viruses (AIVs) have repeatedly caused infections in mammals even humans in many countries. The purpose of our study was to evaluate the acute lung injury (ALI) caused by H9N2 viral infection in mice.
  
  
  METHODS
  Six- to eight- week-old female SPF C57BL/6 mice were infected intranasally with 1 × 10(4) MID50 of A/HONG KONG/2108/2003 [H9N2 (HK)] virus. Clinical signs, pathological changes, virus titration in tissues of mice, arterial blood gas, and cytokines in bronchoalveolar lavage fluid (BALF) and serum were observed at different time points after AIV infection.
  
  
  RESULTS
  H9N2-AIV-infected mice exhibited severe respiratory syndrome, with a mortality rate of 50%. Lung histopathological changes in infected mice included diffuse pneumonia, alveolar damage, inflammatory cellular infiltration, interstitial and alveolar edema, and hemorrhage. In addition, H9N2 viral infection resulted in severe progressive hypoxemia, lymphopenia, and a significant increase in interleukin 1, interleukin 6, tumor necrosis factor, and interferon in BALF and serum.
  
  
  CONCLUSIONS
  The results suggest that H9N2 viral infection induces a typical ALI in mice that resembles the common features of ALI. Our data may facilitate the future studies of potential avian H9N2 disease in humans.
authors.affiliation: Department of Histology, Medical School, Nanjing University, Nanjing, Jiangsu 210093, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Institute of Pathogenic Microbiology, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu 210009, China.
authors.forename: Yunfeng
authors.initials: Y
authors.lastname: Shan
authors.affiliation: Institute of Pathogenic Microbiology, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu 210009, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Chi
authors.affiliation: Institute of Pathogenic Microbiology, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu 210009, China.
authors.forename: Tian
authors.initials: T
authors.lastname: Wen
authors.affiliation: Department of Histology, Medical School, Nanjing University, Nanjing, Jiangsu 210093, China. Emait: hanxd@nju. edu. cn.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Han
mesh_terms: D055371:Acute Lung Injury / Q000097:blood / Q000209:etiology* / Q000821:virology*; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D005260:Female; D053127:Influenza A Virus, H9N2 Subtype / Q000472:pathogenicity*; D007375:Interleukin-1 / Q000097:blood / Q000378:metabolism; D015850:Interleukin-6 / Q000097:blood / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D012137:Respiratory System / Q000821:virology; D014409:Tumor Necrosis Factor-alpha / Q000097:blood / Q000378:metabolism
chemical_list: D007375:Interleukin-1; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha