Rescue of H5N1 subtypeavian influenza A viruslethal to mice

AbstractAvian influenza virus is acquiring the ability to cross the species barrier between birds and mammals. However, the genetic mechanism of this ability is not well known. We successfully rescued aninfluenza A virusA/Chicken/Guangdong/03 (H5N1), which is highly pathogenic to both SPF chickens and BALB/c mice, by plasmid-based reverse genetics. The rescued virus, R-A/Chicken/Guangdong/03 (R-CG), and the wild-type A/Chicken/Guangdong/03 (W-CG) were found to share similar biological properties, such as in titres of 50% egg infectious dose (EID50), 50% tissue culture infectious dose (TCID50) and intravenous pathogenicity index (IPVI). R-CG, like W-CG, is highly pathogenic in mice following natural route infection. Both R-CG and W-CG viruses can be isolated from many organs of mice such as brain, lung, kidney and spleen. As a result, the constructed R-CG reverse genetic system can be used as a tool in the investigation of the molecular mechanism of infection of the mammalian host by avian influenza virus.

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The PA Subunit of the Influenza Virus Polymerase Complex Affects Replication and Airborne Transmission of the H9N2 Subtype Avian Influenza Virus

Viruses ◽

10.3390/v11010040 ◽

2019 ◽

Vol 11 (1) ◽

pp. 40 ◽

Cited By ~ 1

Author(s):

Mengchan Hao ◽

Shaojie Han ◽

Dan Meng ◽

Rong Li ◽

Jing Lin ◽

...

Keyword(s):

Influenza Virus ◽

Avian Influenza ◽

Avian Influenza Virus ◽

Guinea Pigs ◽

Influenza A ◽

Reverse Genetics ◽

Species Barrier ◽

Airborne Transmission ◽

H9n2 Subtype ◽

Influenza A H1n1

The polymerase acidic (PA) protein is the third subunit of the influenza A virus polymerase. In recent years, studies have shown that PA plays an important role in overcoming the host species barrier and host adaptation of the avian influenza virus (AIV). The objective of this study was to elucidate the role of the PA subunit on the replication and airborne transmission of the H9N2 subtype AIV. By reverse genetics, a reassortant rSD01-PA was derived from the H9N2 subtype AIV A/Chicken/Shandong/01/2008 (SD01) by introducing the PA gene from the pandemic influenza A H1N1 virus A/swine/Shandong/07/2011 (SD07). Specific pathogen-free (SPF) chickens and guinea pigs were selected as the animal models for replication and aerosol transmission studies. Results show that rSD01-PA lost the ability of airborne transmission among SPF chickens because of the single substitution of the PA gene. However, rSD01-PA could infect guinea pigs through direct contact, while the parental strain SD01 could not, even though the infection of rSD01-PA could not be achieved through aerosol. In summary, our results indicate that the protein encoded by the PA gene plays a key role in replication and airborne transmission of the H9N2 subtype AIV.

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Highly Pathogenic H5N1 Avian Influenza Virus Induces Extracellular Ca2+ Influx, Leading to Apoptosis in Avian Cells

Journal of Virology ◽

10.1128/jvi.01923-09 ◽

2010 ◽

Vol 84 (6) ◽

pp. 3068-3078 ◽

Cited By ~ 37

Author(s):

Mayo Ueda ◽

Tomo Daidoji ◽

Anariwa Du ◽

Cheng-Song Yang ◽

Madiha S. Ibrahim ◽

...

Keyword(s):

Influenza Virus ◽

Avian Influenza ◽

Avian Influenza Virus ◽

Influenza A Virus ◽

Influenza A ◽

Highly Pathogenic ◽

H5n1 Avian Influenza Virus ◽

H5n1 Avian Influenza ◽

Infected Cells ◽

Pathogenic H5n1

ABSTRACT In this study, we show that the highly pathogenic H5N1 avian influenza virus (AIV) (A/crow/Kyoto/53/04 and A/chicken/Egypt/CL6/07) induced apoptosis in duck embryonic fibroblasts (DEF). In contrast, apoptosis was reduced among cells infected with low-pathogenic AIVs (A/duck/HK/342/78 [H5N2], A/duck/HK/820/80 [H5N3], A/wigeon/Osaka/1/01 [H7N7], and A/turkey/Wisconsin/1/66 [H9N2]). Thus, we investigated the molecular mechanisms of apoptosis induced by H5N1-AIV infection. Caspase-dependent and -independent pathways contributed to the cytopathic effects. We further showed that, in the induction of apoptosis, the hemagglutinin of H5N1-AIV played a major role and its cleavage sequence was not critical. We also observed outer membrane permeabilization and loss of the transmembrane potential of the mitochondria of infected DEF, indicating that mitochondrial dysfunction was caused by the H5N1-AIV infection. We then analyzed Ca2+ dynamics in the infected cells and demonstrated an increase in the concentration of Ca2+ in the cytosol ([Ca2+]i) and mitochondria ([Ca2+]m) after H5N1-AIV infection. Regardless, gene expression important for regulating Ca2+ efflux from the endoplasmic reticulum did not significantly change after H5N1-AIV infection. These results suggest that extracellular Ca2+ may enter H5N1-AIV-infected cells. Indeed, EGTA, which chelates extracellular free Ca2+, significantly reduced the [Ca2+]i, [Ca2+]m, and apoptosis induced by H5N1-AIV infection. In conclusion, we identified a novel mechanism for influenza A virus-mediated cell death, which involved the acceleration of extracellular Ca2+ influx, leading to mitochondrial dysfunction and apoptosis. These findings may be useful for understanding the pathogenesis of H5N1-AIV in avian species as well as the impact of Ca2+ homeostasis on influenza A virus infection.

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Overview of the Epidemiological Situation on Highly Pathogenic Avian Influenza Virus in Russia in 2018

Problems of Particularly Dangerous Infections ◽

10.21055/0370-1069-2019-1-42-49 ◽

2019 ◽

pp. 42-49 ◽

Cited By ~ 4

Author(s):

V. Yu. Marchenko ◽

N. I. Goncharova ◽

V. A. Evseenko ◽

I. M. Susloparov ◽

E. V. Gavrilova ◽

...

Keyword(s):

Influenza Virus ◽

Avian Influenza ◽

Avian Influenza Virus ◽

Influenza A ◽

Wild Birds ◽

Influenza Viruses ◽

Highly Pathogenic ◽

Avian Flu ◽

H9n2 Influenza Virus ◽

Epidemiological Situation

Analyzed was modern epidemiological situation on highly pathogenic avian flu in 2018. Prognosis for possible further distribution of viruses in the territory of Russia was made. In 2018, the situation on highly pathogenic avian flu in Russia was challenging. This was due to the spread of the viruses clade 2.3.4.4, which caused multiple outbreaks among wild birds and poultry in European part of Russia. In addition, A/H5N6 avian influenza virus circulation was for the first time detected in the Saratov Region during routine avian influenza virus surveillance. In May, 2018 two different lineages of avian influenza A/H9N2 were isolated during the outbreaks that occurred at several poultry plants in Primorsk Territory and Amur Region of Russia. Subsequently, that virus subtype continued spreading in Russia, which was recorded by detection of the A/H9N2 influenza virus in wild birds in the Khabarovsk and Tomsk Regions of Russia. Thus, it is shown yet again that the territory of Russia plays an important geographical role in the spread of avian influenza viruses.

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