Department of Veterinary Medicine, University of Maryland, College Park, MD 20742, USA.
Proc Natl Acad Sci U S A. 2011 Jul 19;108(29):12084-8. doi: 10.1073/pnas.1108058108. Epub 2011 Jul 5.
In 2009, a novel H1N1 influenza (pH1N1) virus caused the first influenza pandemic in 40 y. The virus was identified as a triple reassortant between avian, swine, and human influenza viruses, highlighting the importance of reassortment in the generation of viruses with pandemic potential. Previously, we showed that a reassortant virus composed of wild-type avian H9N2 surface genes in a seasonal human H3N2 backbone could gain efficient respiratory droplet transmission in the ferret model. Here we determine the ability of the H9N2 surface genes in the context of the internal genes of a pH1N1 virus to efficiently transmit via respiratory droplets in ferrets. We generated reassorted viruses carrying the HA gene alone or in combination with the NA gene of a prototypical H9N2 virus in the background of a pH1N1 virus. Four reassortant viruses were generated, with three of them showing efficient respiratory droplet transmission. Differences in replication efficiency were observed for these viruses; however, the results clearly indicate that H9N2 avian influenza viruses and pH1N1 viruses, both of which have occasionally infected pigs, have the potential to reassort and generate novel viruses with respiratory transmission potential in mammals.
2009 年，一种新型 H1N1 流感（pH1N1）病毒引发了 40 年来的首次流感大流行。该病毒被鉴定为一种禽流感、猪流感和人流感病毒的三重重组病毒，这突出了重配在产生具有大流行潜力的病毒中的重要性。此前，我们曾表明，一种由野生型禽流感 H9N2 表面基因组成、季节性人流感 H3N2 为骨干的重组病毒，能够在雪貂模型中高效地通过呼吸道飞沫传播。在这里，我们确定了 pH1N1 病毒内部基因背景下的 H9N2 表面基因，在雪貂中通过呼吸道飞沫有效传播的能力。我们生成了携带 HA 基因的重组病毒，或在 pH1N1 病毒背景下携带 H9N2 病毒的 NA 基因的重组病毒。生成了四种重组病毒，其中三种具有高效的呼吸道飞沫传播能力。这些病毒的复制效率存在差异；然而，结果清楚地表明，禽流感 H9N2 病毒和 pH1N1 病毒都曾偶尔感染过猪，它们有潜力发生重配，并产生在哺乳动物中具有呼吸道传播潜力的新型病毒。
