Intestinal microbiota promote enteric virus replication and systemic pathogenesis

Sharon K. Kuss et al. ( 2011 ) Science. 334(6053): 249–252

Speaker: Pei- Huan Lee (李佩寰)                                         Time: 2012/3/7 13:10-14:00

Commentator: Dr. Ching Chuan Liu (劉清泉醫師)             Place: Room 601

Abstract

The importance of the gut microbiota in regulating host health and disease has been studied. However, the effect of bacteria on enteric virus infection is still unclear. To investigate the role of intestinal microbiota on enteric virus pathogenesis, the authors used human poliovirus to infect the mouse strain that expresses its receptor. They found that mice treated with antibiotic showed minimal viral replication and lower mortality than untreated counterparts. They showed that the existence of intestinal microbe prior to poliovirus infection could enhance poliovirus infectivity. Further, they revealed that enhancement of poliovirus infectivity did not require live bacteria ,even N-acetylglucosamine(GlcNAc)-containing polysaccharides alone could enhance the infection. Moreover, lipopolysaccharide(LPS) was the most potent enhancer of poliovirus infectivity. They found that when poliovirus binds to specific microbe-associated surface polysaccharides , such as lipopolysaccharide(LPS) or peptidoglycan(PG), the attachment to host cells is enhanced. Finally, the authors demonstrated that not only poliovirus but another enteric virus, reovirus, causes more severe disease in the present of intestinal microbes. In conclusion, this study revealed that intestinal microbiota promotes enteric virus infection via promoting virus-cell association and aids virus replication.

References

1.  Garrett WS, et al. (2010) Homeostasis and inflammation in the intestine. Cell. 140(6):859-70.

2.  Elizabeth Pennisi. (2011) Gut Bacteria Lend a Molecular Hand to Viruses. Science. 334(6053):168.