title: Interleukin-17 enhances the removal of respiratory syncytial virus in mice by promoting neutrophil migration and reducing interferon-gamma expression.
abstract: The aim of this study was to observe the effect of interleukin (IL)-17 on early immune response and inflammation in the lungs of respiratory syncytial virus (RSV)-infected mice. Specific pathogen-free BALB/c mice were randomly assigned to control, RSV-infected, RSV-infected with phosphate-buffered saline, and RSV-infected + IL-17 intervention groups. The RSV infection model was set up by nasal mucosa immunization. The intervention group was provided with restructured IL-17 (intranasal). The viral load and cytokine concentrations in the lung tissues and broncho-alveolar lavage fluid (BALF) were determined by real-time-polymerase chain reaction and enzyme-linked immunosorbent assay. RSV caused acute lung inflammation in mice with a significantly higher number of neutrophils and cytokines such as interferon-gamma (IFN-γ), IL-1β, IL-6, and G-CSF in the BALF than that in the control group. IL-17 intervention led to a significant increase in the number of neutrophilic granulocytes in the BALF. Alternately, IL-17 intervention led to a significant decrease in the IFN-γ concentration and a significant increase in the IL-1β, IL-6 and G-CSF levels in the BALF. IL-17 induced a reduction in the viral load and an increase in the survival rate of mice on the third day of infection. IL- 17 mucosal immunity enhances the removal of RSV and strengthens the immune defense by promoting neutrophil migration and reducing the IFN-γ levels in mouse lungs.
authors.affiliation: Department of Critical Care Medicine, Sir Run Run Shaw Hospital, Medical Department of Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: G
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Institute of Viral Disease, Zhejiang Academy of Medical Sciences, Hangzhou, China.
authors.forename: K F
authors.initials: KF
authors.lastname: Zhou
authors.affiliation: Department of Critical Care Medicine, Sir Run Run Shaw Hospital, Medical Department of Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Z H
authors.initials: ZH
authors.lastname: Lu
mesh_terms: D000818:Animals; D016179:Granulocyte Colony-Stimulating Factor / Q000378:metabolism; D007371:Interferon-gamma / Q000378:metabolism*; D020381:Interleukin-17 / Q000627:therapeutic use*; D015850:Interleukin-6 / Q000378:metabolism; D008168:Lung / Q000821:virology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009504:Neutrophils / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D018357:Respiratory Syncytial Virus Infections / Q000188:drug therapy* / Q000378:metabolism; D012136:Respiratory Syncytial Viruses / Q000187:drug effects* / Q000472:pathogenicity*
chemical_list: D020381:Interleukin-17; D015850:Interleukin-6; D016179:Granulocyte Colony-Stimulating Factor; D007371:Interferon-gamma