+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Tissue tropism of swine influenza viruses and reassortants in ex vivo cultures of the human respiratory tract and conjunctiva



Tissue tropism of swine influenza viruses and reassortants in ex vivo cultures of the human respiratory tract and conjunctiva



Journal of Virology 85(22): 11581



The 2009 pandemic influenza H1N1 (H1N1pdm) virus was generated by reassortment of swine influenza viruses of different lineages. This was the first influenza pandemic to emerge in over 4 decades and the first to occur after the realization that influenza pandemics arise from influenza viruses of animals. In order to understand the biological determinants of pandemic emergence, it is relevant to compare the tropism of different lineages of swine influenza viruses and reassortants derived from them with that of 2009 pandemic H1N1 (H1N1pdm) and seasonal influenza H1N1 viruses in ex vivo cultures of the human nasopharynx, bronchus, alveoli, and conjunctiva. We hypothesized that virus which can transmit efficiently between humans replicated well in the human upper airways. As previously reported, H1N1pdm and seasonal H1N1 viruses replicated efficiently in the nasopharyngeal, bronchial, and alveolar epithelium. In contrast, representative viruses from the classical swine (CS) (H1N1) lineage could not infect human respiratory epithelium; Eurasian avian-like swine (EA) (H1N1) viruses only infected alveolar epithelium and North American triple-reassortant (TRIG) viruses only infected the bronchial epithelium albeit inefficiently. Interestingly, a naturally occurring triple-reassortant swine virus, A/SW/HK/915/04 (H1N2), with a matrix gene segment of EA swine derivation (i.e., differing from H1N1pdm only in lacking a neuraminidase [NA] gene of EA derivation) readily infected and replicated in human nasopharyngeal and bronchial epithelia but not in the lung. A recombinant sw915 with the NA from H1N1pdm retained its tropism for the bronchus and acquired additional replication competence for alveolar epithelium. In contrast to H1N1pdm, none of the swine viruses tested nor seasonal H1N1 had tropism in human conjunctiva. Recombinant viruses generated by swapping the surface proteins (hemagglutinin and NA) of H1N1pdm and seasonal H1N1 virus demonstrated that these two gene segments together are key determinants of conjunctival tropism. Overall, these findings suggest that ex vivo cultures of the human respiratory tract provide a useful biological model for assessing the human health risk of swine influenza viruses.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 056593152

Download citation: RISBibTeXText

PMID: 21880750

DOI: 10.1128/jvi.05662-11


Related references

Tropism and innate host response of the 2009 pandemic H1N1 influenza virus compared with related swine influenza viruses and reassortants in ex vivo and in vitro cultures of the human respiratory tract and conjunctiva. Influenza and other Respiratory Viruses 5(Suppl 1): 54-55, 2011

Tropism and innate host responses of the 2009 pandemic H1N1 influenza virus in ex vivo and in vitro cultures of human conjunctiva and respiratory tract. American Journal of Pathology 176(4): 1828-1840, 2010

Use of ex vivo and in vitro cultures of the human respiratory tract to study the tropism and host responses of highly pathogenic avian influenza A (H5N1) and other influenza viruses. Virus Research 178(1): 133-145, 2013

Phylogenetically distinct equine influenza viruses show different tropism for the swine respiratory tract. Journal of General Virology 96(Pt 5): 969-974, 2015

Tropism and innate host responses of a novel avian influenza A H7N9 virus: an analysis of ex-vivo and in-vitro cultures of the human respiratory tract. Lancet. Respiratory Medicine 1(7): 534-542, 2013

Risk Assessment of the Tropism and Pathogenesis of the Highly Pathogenic Avian Influenza A/H7N9 Virus Using Ex Vivo and In Vitro Cultures of Human Respiratory Tract. Journal of Infectious Diseases 220(4): 578-588, 2019

Tropism of H7N9 influenza viruses in the human respiratory tract. Lancet. Respiratory Medicine 1(7): 501-502, 2013

Tropism of influenza B viruses in human respiratory tract explants and airway organoids. European Respiratory Journal 54(2):, 2019

Evolutionary pathways of N2 neuraminidases of swine and human influenza A viruses: origin of the neuraminidase genes of two reassortants (H1N2) isolated from pigs. Journal of General Virology 72: 693-698, 1991

Human H7N9 influenza A viruses replicate in swine respiratory tissue explants. Journal of Virology 87(22): 12496, 2013

Seasonal and pandemic human influenza viruses attach better to human upper respiratory tract epithelium than avian influenza viruses. American Journal of Pathology 176(4): 1614-1618, 2010

Tissue tropisms opt for transmissible reassortants during avian and swine influenza A virus co-infection in swine. Plos Pathogens 14(12): E1007417, 2018

The sensitivity of a number of cell cultures to different types of influenza viruses and their reassortants. Voprosy Virusologii 36(1): 10-13, 1991

The effect of different factors on the reproduction of influenza viruses and reassortants in cell cultures. Voprosy Virusologii 36(5): 384-386, 1991

Altered tissue tropism of human-avian reassortant influenza viruses. Virology 128(1): 260-263, 1983