The first pandemic of the 21(st) century, pandemic H1N1 2009 (pH1N1 2009), emerged from a swine-origin source. Although human infections with swine-origin influenza have been reported previously, none went on to cause a pandemic or indeed any sustained human transmission. In previous pandemics, specific residues in the receptor binding site of the haemagglutinin (HA) protein of influenza have been associated with the ability of the virus to transmit between humans. In the present study we investigated the effect of residue 227 in HA on cell tropism and transmission of pH1N1 2009. In pH1N1 2009 and recent seasonal H1N1 viruses this residue is glutamic acid, whereas in swine influenza it is alanine. Using human airway epithelium, we show a differential cell tropism of pH1N1 2009 compared to pH1N1 2009 E227A and swine influenza suggesting this residue may alter the sialic acid conformer binding preference of the HA. Furthermore, both pH1N1 2009 E227A and swine influenza multi-cycle viral growth was found to be attenuated in comparison to pH1N1 2009 in human airway epithelium. However this altered tropism and viral growth in human airway epithelium did not abrogate respiratory droplet transmission of pH1N1 2009 E227A in ferrets. Thus, acquisition of E at residue 227 was not solely responsible for the ability of pH1N1 2009 to transmit between humans.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3187803 | PMC |
| http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0025755 | PLOS |
Publication Analysis
Top Keywords
Similar Publications
Immunization and challenge trials in a murine model using different inactivated recombinant vaccines against H1N1 swine influenza virus circulating in Brazil.
Vaccine
December 2024
Department of Preventive Veterinary Medicine, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil. Electronic address:
In Brazil, at least four lineages of influenza A virus circulate pig population: 2009 H1N1 flu pandemic (pH1N1), human-seasonal origin H3N2, H1N1 and H1N2 (huH1 lineages) viruses. Studies related to the occurrence of swine influenza A virus (SIAV) in Brazilian herds have been detecting an increase of occurrence of huH1 lineages. This study aimed to construct recombinant vaccines against the huH1N1 virus and test the immunogens in a murine model.
View Article and Find Full Text PDFFunctional Analysis of GRSF1 in the Nuclear Export and Translation of Influenza A Virus mRNAs.
Viruses
July 2024
Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA.
Influenza A viruses (IAV) utilize host proteins throughout their life cycle to infect and replicate in their hosts. We previously showed that host adaptive mutations in avian IAV PA help recruit host protein G-Rich RNA Sequence Binding Factor 1 (GRSF1) to the nucleoprotein (NP) 5' untranslated region (UTR), leading to the enhanced nuclear export and translation of NP mRNA. In this study, we evaluated the impact of GRSF1 in the viral life cycle.
View Article and Find Full Text PDFCommon laboratory organic solvents are better medium for molecular detection of RNA viruses using PCR.
Indian J Med Microbiol
June 2024
Department of Virology, Haffkine Institute, Mumbai, India. Electronic address:
Purpose: The unavailability of recommended viral transport medium during epidemics of respiratory viral infections is a substantial healthcare concern. It may prompt the use of alternatives, which may give rise to results with questionable validity. The present study was carried out to assess and validate the utility of commonly available solvents in the hospital/healthcare set-ups which may be used as ready and economical alternatives to commercial VTMs.
View Article and Find Full Text PDFInfluenza antibody breadth and effector functions are immune correlates from acquisition of pandemic infection of children.
Nat Commun
April 2024
HKU-Pasteur Research Pole, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, SAR, China.
Article Synopsis
- Seasonal vaccination can enhance antibodies and Fc receptor (FcR) functions, potentially reducing the severity of pandemic influenza infections, even in the absence of neutralizing antibodies.
- In a study using serum from children vaccinated against seasonal influenza prior to the 2009 H1N1 pandemic, elevated FcR effector functions and specific antibody profiles were observed in unvaccinated children who did not get infected.
- The findings suggest that while seasonal vaccination plays a beneficial role, some children possess pre-existing broadly reactive antibodies with FcR capabilities, potentially classifying them as 'elite influenza controllers' capable of resisting infections effectively.
Characterization of viral infections in children with influenza-like-illness during December 2018-January 2019.
Front Cell Infect Microbiol
February 2024
Vanke School of Public Health, Tsinghua University, Beijing, China.
Introduction: Respiratory viral infection (RVI) is of very concern after the outbreak of COVID-19, especially in pediatric departments. Learning pathogen spectrum of RVI in children previous the epidemic of COVID-19 could provide another perspective for understanding RVI under current situation and help to prepare for the post COVID-19 infection control.
Methods: A nucleic acid sequence-based amplification (NASBA) assay, with 19 pairs of primers targeting various respiratory viruses, was used for multi-pathogen screening of viral infections in children presenting influenza-like illness (ILI) symptoms.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!