Antigenic drift of hemagglutinin and neuraminidase in seasonal H1N1 influenza viruses from Saudi Arabia in 2014 to 2015

ABSTRACT History suggests that the 2009 pandemic H1N1 influenza virus faces extinction unless it mutates to avoid already high global population immunity. The immune escape mechanisms potentially at its disposal include antigenic drift, antigenic shift via genetic reassortment, and intrasubtypic reassortment. Going back to the late 19th century, the evolutionary histories of past pandemic viruses are examined in an effort to better understand the nature and extent of the immune pressures faced by the 2009 pandemic virus in the immediate future. While human influenza viruses have often surprised us, available evidence leads to the hope that the current pandemic virus will continue to cause low or moderate mortality rates if it does not become extinct.

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Possible correlation between low antigenic drift of A(H1N1) influenza viruses and induction of HI antibodies

European Journal of Epidemiology ◽

10.1007/bf00499457 ◽

1996 ◽

Vol 12 (6) ◽

pp. 589-594 ◽

Cited By ~ 3

Author(s):

Anna Maria Iorio ◽

Tiziana Zei ◽

Mariella Neri ◽

Adriano Alatri

Keyword(s):

H1n1 Influenza ◽

Influenza Viruses ◽

Antigenic Drift

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Human Dendritic Cell Response Signatures Distinguish 1918, Pandemic, and Seasonal H1N1 Influenza Viruses

Journal of Virology ◽

10.1128/jvi.01523-15 ◽

2015 ◽

Vol 89 (20) ◽

pp. 10190-10205 ◽

Cited By ~ 20

Author(s):

Boris M. Hartmann ◽

Juilee Thakar ◽

Randy A. Albrecht ◽

Stefan Avey ◽

Elena Zaslavsky ◽

...

Keyword(s):

Immune Responses ◽

Human Health ◽

New Caledonia ◽

H1n1 Influenza ◽

Influenza Viruses ◽

Antigenic Drift ◽

Clinical Severity ◽

Time Shift ◽

Specific Response ◽

Transcriptional Responses

ABSTRACTInfluenza viruses continue to present global threats to human health. Antigenic drift and shift, genetic reassortment, and cross-species transmission generate new strains with differences in epidemiology and clinical severity. We compared the temporal transcriptional responses of human dendritic cells (DC) to infection with two pandemic (A/Brevig Mission/1/1918, A/California/4/2009) and two seasonal (A/New Caledonia/20/1999, A/Texas/36/1991) H1N1 influenza viruses. Strain-specific response differences included stronger activation of NF-κB following infection with A/New Caledonia/20/1999 and a unique cluster of genes expressed following infection with A/Brevig Mission/1/1918. A common antiviral program showing strain-specific timing was identified in the early DC response and found to correspond with reported transcript changes in blood during symptomatic human influenza virus infection. Comparison of the global responses to the seasonal and pandemic strains showed that a dramatic divergence occurred after 4 h, with only the seasonal strains inducing widespread mRNA loss.IMPORTANCEContinuously evolving influenza viruses present a global threat to human health; however, these host responses display strain-dependent differences that are incompletely understood. Thus, we conducted a detailed comparative study assessing the immune responses of human DC to infection with two pandemic and two seasonal H1N1 influenza strains. We identified in the immune response to viral infection both common and strain-specific features. Among the stain-specific elements were a time shift of the interferon-stimulated gene response, selective induction of NF-κB signaling by one of the seasonal strains, and massive RNA degradation as early as 4 h postinfection by the seasonal, but not the pandemic, viruses. These findings illuminate new aspects of the distinct differences in the immune responses to pandemic and seasonal influenza viruses.

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Cocirculation of Swine H1N1 Influenza A Virus Lineages in Germany

Viruses ◽

10.3390/v12070762 ◽

2020 ◽

Vol 12 (7) ◽

pp. 762 ◽

Cited By ~ 1

Author(s):

Roland Zell ◽

Marco Groth ◽

Andi Krumbholz ◽

Jeannette Lange ◽

Anja Philipps ◽

...

Keyword(s):

Influenza A ◽

Antigenic Variation ◽

Phylogenetic Analyses ◽

Swine Influenza Virus ◽

Swine Influenza ◽

H1n1 Influenza ◽

Influenza Viruses ◽

Antigenic Drift ◽

Influenza Surveillance ◽

Northwest Germany

The genome analysis of 328 H1N1 swine influenza virus isolates collected in a 13-year long-term swine influenza surveillance in Germany is reported. Viral genomes were sequenced with the Illumina next-generation sequencing technique and conventional Sanger methods. Phylogenetic analyses were conducted with Bayesian tree inference. The results indicate continued prevalence of Eurasian avian swine H1N1 but also emergence of a novel H1N1 reassortant, named Schneiderkrug/2013-like swine H1N1, with human-like hemagglutinin and avian-like neuraminidase and internal genes. Additionally, the evolution of an antigenic drift variant of A (H1N1) pdm09 was observed, named Wachtum/2014-like swine H1N1. Both variants were first isolated in northwest Germany, spread to neighboring German states and reached greater proportions of the H1N1 isolates of 2014 and 2015. The upsurge of Wachtum/2014-like swine H1N1 is of interest as this is the first documented persistent swine-to-swine spread of A (H1N1) pdm09 in Germany associated with antigenic variation. Present enzootic swine influenza viruses in Germany now include two or more co-circulating, antigenically variant viruses of each of the subtypes, H1N1 and H1N2.

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Identification of the binding sites to monoclonal antibodies on A/USSR/90/77 (H1N1) hemagglutinin and their involvement in antigenic drift in H1N1 influenza viruses

Virology ◽

10.1016/0042-6822(83)90538-x ◽

1983 ◽

Vol 131 (1) ◽

pp. 116-127 ◽

Cited By ~ 24

Author(s):

Setsuko Nakajima ◽

Katsuhisa Nakajima ◽

Alan P. Kendal

Keyword(s):

Monoclonal Antibodies ◽

Binding Sites ◽

H1n1 Influenza ◽

Influenza Viruses ◽

Antigenic Drift

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Faculty Opinions recommendation of Antigenic and genetic characteristics of swine-origin 2009 A(H1N1) influenza viruses circulating in humans.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1161936.626239 ◽

2009 ◽

Author(s):

Charles Chiu

Keyword(s):

H1n1 Influenza ◽

Influenza Viruses ◽

Genetic Characteristics

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Sequential Seasonal H1N1 Influenza Virus Infections Protect Ferrets against Novel 2009 H1N1 Influenza Virus

Journal of Virology ◽

10.1128/jvi.02257-12 ◽

2012 ◽

Vol 87 (3) ◽

pp. 1400-1410 ◽

Cited By ~ 45

Author(s):

Donald M. Carter ◽

Chalise E. Bloom ◽

Eduardo J. M. Nascimento ◽

Ernesto T. A. Marques ◽

Jodi K. Craigo ◽

...

Keyword(s):

Influenza Virus ◽

H1n1 Influenza ◽

Cross Reactivity ◽

Influenza Viruses ◽

The Novel ◽

Virus Infections ◽

H1n1 Influenza Virus ◽

Virus Shedding ◽

2009 H1n1 ◽

Novel H1n1 Influenza

ABSTRACTIndividuals <60 years of age had the lowest incidence of infection, with ∼25% of these people having preexisting, cross-reactive antibodies to novel 2009 H1N1 influenza. Many people >60 years old also had preexisting antibodies to novel H1N1. These observations are puzzling because the seasonal H1N1 viruses circulating during the last 60 years were not antigenically similar to novel H1N1. We therefore hypothesized that a sequence of exposures to antigenically different seasonal H1N1 viruses can elicit an antibody response that protects against novel 2009 H1N1. Ferrets were preinfected with seasonal H1N1 viruses and assessed for cross-reactive antibodies to novel H1N1. Serum from infected ferrets was assayed for cross-reactivity to both seasonal and novel 2009 H1N1 strains. These results were compared to those of ferrets that were sequentially infected with H1N1 viruses isolated prior to 1957 or more-recently isolated viruses. Following seroconversion, ferrets were challenged with novel H1N1 influenza virus and assessed for viral titers in the nasal wash, morbidity, and mortality. There was no hemagglutination inhibition (HAI) cross-reactivity in ferrets infected with any single seasonal H1N1 influenza viruses, with limited protection to challenge. However, sequential H1N1 influenza infections reduced the incidence of disease and elicited cross-reactive antibodies to novel H1N1 isolates. The amount and duration of virus shedding and the frequency of transmission following novel H1N1 challenge were reduced. Exposure to multiple seasonal H1N1 influenza viruses, and not to any single H1N1 influenza virus, elicits a breadth of antibodies that neutralize novel H1N1 even though the host was never exposed to the novel H1N1 influenza viruses.

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Next Generation of Computationally Optimized Broadly Reactive HA Vaccines Elicited Cross-Reactive Immune Responses and Provided Protection against H1N1 Virus Infection

Vaccines ◽

10.3390/vaccines9070793 ◽

2021 ◽

Vol 9 (7) ◽

pp. 793

Author(s):

Ying Huang ◽

Monique S. França ◽

James D. Allen ◽

Hua Shi ◽

Ted M. Ross

Keyword(s):

Influenza Virus ◽

Virus Infection ◽

Immune Responses ◽

H1n1 Virus ◽

Influenza Virus Infection ◽

H1n1 Influenza ◽

Influenza Viruses ◽

Next Generation ◽

Wild Type ◽

Influenza A H1n1

Vaccination is the best way to prevent influenza virus infections, but the diversity of antigenically distinct isolates is a persistent challenge for vaccine development. In order to conquer the antigenic variability and improve influenza virus vaccine efficacy, our research group has developed computationally optimized broadly reactive antigens (COBRAs) in the form of recombinant hemagglutinins (rHAs) to elicit broader immune responses. However, previous COBRA H1N1 vaccines do not elicit immune responses that neutralize H1N1 virus strains in circulation during the recent years. In order to update our COBRA vaccine, two new candidate COBRA HA vaccines, Y2 and Y4, were generated using a new seasonal-based COBRA methodology derived from H1N1 isolates that circulated during 2013–2019. In this study, the effectiveness of COBRA Y2 and Y4 vaccines were evaluated in mice, and the elicited immune responses were compared to those generated by historical H1 COBRA HA and wild-type H1N1 HA vaccines. Mice vaccinated with the next generation COBRA HA vaccines effectively protected against morbidity and mortality after infection with H1N1 influenza viruses. The antibodies elicited by the COBRA HA vaccines were highly cross-reactive with influenza A (H1N1) pdm09-like viruses isolated from 2009 to 2021, especially with the most recent circulating viruses from 2019 to 2021. Furthermore, viral loads in lungs of mice vaccinated with Y2 and Y4 were dramatically reduced to low or undetectable levels, resulting in minimal lung injury compared to wild-type HA vaccines following H1N1 influenza virus infection.

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Origin of the European avian-like swine influenza viruses

Journal of General Virology ◽

10.1099/vir.0.068569-0 ◽

2014 ◽

Vol 95 (11) ◽

pp. 2372-2376 ◽

Cited By ~ 10

Author(s):

Andi Krumbholz ◽

Jeannette Lange ◽

Andreas Sauerbrei ◽

Marco Groth ◽

Matthias Platzer ◽

...

Keyword(s):

Avian Influenza ◽

Phylogenetic Trees ◽

Sequence Data ◽

Swine Influenza ◽

H1n1 Influenza ◽

Molecular Data ◽

Influenza Viruses ◽

Time Resolved ◽

Genotype Constellation ◽

Tree Inference

The avian-like swine influenza viruses emerged in 1979 in Belgium and Germany. Thereafter, they spread through many European swine-producing countries, replaced the circulating classical swine H1N1 influenza viruses, and became endemic. Serological and subsequent molecular data indicated an avian source, but details remained obscure due to a lack of relevant avian influenza virus sequence data. Here, the origin of the European avian-like swine influenza viruses was analysed using a collection of 16 European swine H1N1 influenza viruses sampled in 1979–1981 in Germany, the Netherlands, Belgium, Italy and France, as well as several contemporaneous avian influenza viruses of various serotypes. The phylogenetic trees suggested a triple reassortant with a unique genotype constellation. Time-resolved maximum clade credibility trees indicated times to the most recent common ancestors of 34–46 years (before 2008) depending on the RNA segment and the method of tree inference.

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