[Respiratory syncytial virus increases the expression and release of high mobility group Box-1 protein in the lung tissue of mice].
OBJECTIVE
To investigate the expression and release of high mobility group Box-1 protein (HMGB1) in the lung tissue of mice with respiratory syncytial virus (RSV) infection.


METHODS
Eighteen mice were randomized into PBS control group, RSV group and RSV/ribavirin group. Seven days after RSV infection in the mice in the latter two groups, the bronchoalveolar lavage fluid (BALF) was collected for cell counting and classification, and the levels of IL-4, IFN-gamma and HMGB1 in the supernatants of the BALF were detected. The left lungs of the mice were harvested for pathological examination with HE staining, and the right lungs were taken for detecting the expression of HMGB1 by Western blotting.


RESULTS
RSV induced a TH1 inflammation in the lung tissue as shown by significantly increased IFN-gamma and decreased IL-4 levels in the BALF. The total BALF cells, neutrophils and macrophages in the RSV group were significantly higher than those in the control group (P<0.05), and the cell counts were significantly decreased by ribavirin treatment (P<0.05). HE staining showed neutrophil and lymphocyte infiltration in the lumen and submucous layer of the airway in RSV group. The level of HMGB1 in the BALF significantly increased in the RSV group as compared with that in the control group (P<0.05), but was lowered by ribavirin treatment (P<0.05). The expression of the HMGB1 in the lung tissue significantly increased in the RSV group in comparison with that in the control group (P<0.05), and was not significantly decreased by ribavirin treatment (P>0.05).


CONCLUSIONS
The increased expression and release of HMGB1 in the lung tissue of mice with RSV infection is probably involved in the development of RSV infection-related lung diseases.
Hou
Chang-chun
CC
Department of Respiratory Diseases, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China. houchangchun305@163.com
Zhao
Hai-jin
HJ
Cai
Shao-xi
SX
Li
Wen-jun
WJ
Tong
Wan-cheng
WC
Liu
Lai-yu
LY
D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D005260:Female; D024243:HMGB1 Protein / Q000096:biosynthesis* / Q000235:genetics; D008168:Lung / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D011897:Random Allocation; D018357:Respiratory Syncytial Virus Infections / Q000378:metabolism*
D024243:HMGB1 Protein