Genetic tuning of avian influenza A (H7N9) virus promotes viral fitness within different species

Zhu, Wenfei; Shu, Yuelong

doi:10.1016/j.micinf.2014.11.010

Cited by 18 publications

(16 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…6). Previously we reported that "genetic tuning" mediated the genesis and interspecies transmission of novel H7N9 viruses (37,38). As HPAI H5N6 viruses circulate in environments similar to those of H7N9 viruses, the same forces of evolution may affect H5N6 viruses.…”

Section: Discussionmentioning

confidence: 99%

Genesis and Dissemination of Highly Pathogenic H5N6 Avian Influenza Viruses

Yang

Zhu

et al. 2017

J Virol

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Discussionmentioning

confidence: 99%

Genesis and Dissemination of Highly Pathogenic H5N6 Avian Influenza Viruses

Yang

Zhu

et al. 2017

J Virol

Self Cite

View full text Add to dashboard Cite

show abstract

“…Previous studies on the H7N9 virus have elucidated the potential origin and source of the virus (2)(3)(4)(5)(6). Dynamic reassortment among H7N9 and H9N2 viruses has been reported to increase the diversity of the virus (3-5, 7, 8).…”

mentioning

confidence: 99%

Two Outbreak Sources of Influenza A (H7N9) Viruses Have Been Established in China

Wang

Yang

Zhu

et al. 2016

J Virol

Self Cite

View full text Add to dashboard Cite

Due to enzootic infections in poultry and persistent human infections in China, influenza A (H7N9) virus has remained a public health threat. The Yangtze River Delta region, which is located in eastern China, is well recognized as the original source for H7N9 outbreaks. Based on the evolutionary analysis of H7N9 viruses from all three outbreak waves since 2013, we identified the Pearl River Delta region as an additional H7N9 outbreak source. H7N9 viruses are repeatedly introduced from these two sources to the other areas, and the persistent circulation of H7N9 viruses occurs in poultry, causing continuous outbreak waves. Poultry movements may contribute to the geographic expansion of the virus. In addition, the AnH1 genotype, which was predominant during wave 1, was replaced by JS537, JS18828, and AnH1887 genotypes during waves 2 and 3. The establishment of a new source and the continuous evolution of the virus hamper the elimination of H7N9 viruses, thus posing a long-term threat of H7N9 infection in humans. Therefore, both surveillance of H7N9 viruses in humans and poultry and supervision of poultry movements should be strengthened. IMPORTANCESince its occurrence in humans in eastern China in spring 2013, the avian H7N9 viruses have been demonstrating the continuing pandemic threat posed by the current influenza ecosystem in China. As the viruses are silently circulated in poultry, with potentially severe outcomes in humans, H7N9 virus activity in humans in China is very important to understand. In this study, we identified a newly emerged H7N9 outbreak source in the Pearl River Delta region. Both sources in the Yangtze River Delta region and the Pearl River Delta region have been established and found to be responsible for the H7N9 outbreaks in mainland China.

show abstract

“…We found that memory CD4 T cells specific for H5 HA persisted in subjects vaccinated many years earlier and that these could be recruited into a subsequent immune response to vaccination, enabling a greatly enhanced antibody response to a serologically distinct H5N1-derived virus (20). Should avian influenza viruses continue to pose a threat to humans (54)(55)(56)(57)(58)(59)(60)(61)(62)(63)(64), such a prepandemic strategy could enhance vaccine responsiveness in "at risk" subjects and enhance early and potentially protective antibody responses in infected individuals.…”

Section: Discussionmentioning

confidence: 93%

Avian and Human Seasonal Influenza Hemagglutinin Proteins Elicit CD4 T Cell Responses That Are Comparable in Epitope Abundance and Diversity

DiPiazza

Richards

Poulton

et al. 2017

Clin Vaccine Immunol

View full text Add to dashboard Cite

Avian influenza viruses remain a significant concern due to their pandemic potential. Vaccine trials have suggested that humans respond poorly to avian influenza vaccines relative to seasonal vaccines. It is important to understand, first, if there is a general deficiency in the ability of avian hemagglutinin (HA) proteins to generate immune responses and, if so, what underlies this defect. This question is of particular interest because it has been suggested that in humans, the poor immunogenicity of H7 vaccines may be due to a paucity of CD4 T cell epitopes. Because of the generally high levels of cross-reactive CD4 T cells in humans, it is not possible to compare the inherent immunogenicities of avian and seasonal HA proteins in an unbiased manner. Here, we empirically examine the epitope diversity and abundance of CD4 T cells elicited by seasonal and avian HA proteins. HLA-DR1 and HLA-DR4 transgenic mice were vaccinated with purified HA proteins, and CD4 T cells to specific epitopes were identified and quantified. These studies revealed that the diversity and abundance of CD4 T cells specific for HA do not segregate on the basis of whether the HA was derived from human seasonal or avian influenza viruses. Therefore, we conclude that failure in responses to avian vaccines in humans is likely due to a lack of cross-reactive CD4 T cell memory perhaps coupled with competition with or suppression of naive, HA-specific CD4 T cells by memory CD4 T cells specific for more highly conserved proteins.

show abstract

Genetic tuning of avian influenza A (H7N9) virus promotes viral fitness within different species

Cited by 18 publications

References 45 publications

Genesis and Dissemination of Highly Pathogenic H5N6 Avian Influenza Viruses

Genesis and Dissemination of Highly Pathogenic H5N6 Avian Influenza Viruses

Two Outbreak Sources of Influenza A (H7N9) Viruses Have Been Established in China

Avian and Human Seasonal Influenza Hemagglutinin Proteins Elicit CD4 T Cell Responses That Are Comparable in Epitope Abundance and Diversity

Contact Info

Product

Resources

About