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

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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Next generation methodology for updating HA vaccines against emerging human seasonal influenza A(H3N2) viruses

Scientific Reports ◽

10.1038/s41598-020-79590-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

James D. Allen ◽

Ted M. Ross

Keyword(s):

Influenza Virus ◽

Immune Responses ◽

Influenza A ◽

Seasonal Influenza ◽

Influenza Viruses ◽

Next Generation ◽

Virus Infections ◽

Wild Type ◽

Influenza Hemagglutinin ◽

H3n2 Influenza

AbstractWhile vaccines remain the best tool for preventing influenza virus infections, they have demonstrated low to moderate effectiveness in recent years. Seasonal influenza vaccines typically consist of wild-type influenza A and B viruses that are limited in their ability to elicit protective immune responses against co-circulating influenza virus variant strains. Improved influenza virus vaccines need to elicit protective immune responses against multiple influenza virus drift variants within each season. Broadly reactive vaccine candidates potentially provide a solution to this problem, but their efficacy may begin to wane as influenza viruses naturally mutate through processes that mediates drift. Thus, it is necessary to develop a method that commercial vaccine manufacturers can use to update broadly reactive vaccine antigens to better protect against future and currently circulating viral variants. Building upon the COBRA technology, nine next-generation H3N2 influenza hemagglutinin (HA) vaccines were designed using a next generation algorithm and design methodology. These next-generation broadly reactive COBRA H3 HA vaccines were superior to wild-type HA vaccines at eliciting antibodies with high HAI activity against a panel of historical and co-circulating H3N2 influenza viruses isolated over the last 15 years, as well as the ability to neutralize future emerging H3N2 isolates.

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Tropism and Infectivity of a Seasonal A(H1N1) and a Highly Pathogenic Avian A(H5N1) Influenza Virus in Primary Differentiated Ferret Nasal Epithelial Cell Cultures

Journal of Virology ◽

10.1128/jvi.00080-19 ◽

2019 ◽

Vol 93 (10) ◽

Cited By ~ 6

Author(s):

Hui Zeng ◽

Cynthia S. Goldsmith ◽

Amrita Kumar ◽

Jessica A. Belser ◽

Xiangjie Sun ◽

...

Keyword(s):

Influenza Virus ◽

Virus Infection ◽

Avian Influenza ◽

H5n1 Virus ◽

H1n1 Virus ◽

Influenza Virus Infection ◽

Influenza Viruses ◽

Host Interactions ◽

Culture Model

ABSTRACTFerrets represent an invaluable animal model to study influenza virus pathogenesis and transmission. To further characterize this model, we developed a differentiated primary ferret nasal epithelial cell (FNEC) culture model for investigation of influenza A virus infection and virus-host interactions. This well-differentiated culture consists of various cell types, a mucociliary clearance system, and tight junctions, representing the nasal ciliated pseudostratified respiratory epithelium. Both α2,6-linked and α2,3-linked sialic acid (SA) receptors, which preferentially bind the hemagglutinin (HA) of human and avian influenza viruses, respectively, were detected on the apical surface of the culture with different cellular tropisms. In accordance with the distribution of SA receptors, we observed that a pre-2009 seasonal A(H1N1) virus infected both ciliated and nonciliated cells, whereas a highly pathogenic avian influenza (HPAI) A(H5N1) virus primarily infected nonciliated cells. Transmission electron microscopy revealed that virions were released from or associated with the apical membranes of ciliated, nonciliated, and mucin-secretory goblet cells. Upon infection, the HPAI A(H5N1) virus replicated to titers higher than those of the human A(H1N1) virus at 37°C; however, replication of the A(H5N1) virus was significantly attenuated at 33°C. Furthermore, we found that infection with the A(H5N1) virus induced higher expression levels of immune mediator genes and resulted in more cell damage/loss than with the human A(H1N1) virus. This primary differentiated FNEC culture model, recapitulating the structure of the nasal epithelium, provides a useful model to bridgein vivoandin vitrostudies of cellular tropism, infectivity, and pathogenesis of influenza viruses during the initial stages of infection.IMPORTANCEAlthough ferrets serve as an important model of influenza virus infection, much remains unknown about virus-host interactions in this species at the cellular level. The development of differentiated primary cultures of ferret nasal epithelial cells is an important step toward understanding cellular tropism and the mechanisms of influenza virus infection and replication in the airway milieu of this model. Using lectin staining and microscopy techniques, we characterized the sialic acid receptor distribution and the cellular composition of the culture model. We then evaluated the replication of and immune response to human and avian influenza viruses at relevant physiological temperatures. Our findings offer significant insight into this first line of defense against influenza virus infection and provide a model for the evaluation of emerging influenza viruses in a well-controlledin vitroenvironmental setting.

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Contemporary Seasonal Influenza A (H1N1) Virus Infection Primes for a More Robust Response To Split Inactivated Pandemic Influenza A (H1N1) Virus Vaccination in Ferrets

Clinical and Vaccine Immunology ◽

10.1128/cvi.00247-10 ◽

2010 ◽

Vol 17 (12) ◽

pp. 1998-2006 ◽

Cited By ~ 11

Author(s):

Ali H. Ellebedy ◽

Thomas P. Fabrizio ◽

Ghazi Kayali ◽

Thomas H. Oguin ◽

Scott A. Brown ◽

...

Keyword(s):

Influenza Virus ◽

Pandemic Influenza ◽

Influenza A ◽

Seasonal Influenza ◽

H1n1 Virus ◽

H1n1 Influenza ◽

Influenza Viruses ◽

Inactivated Vaccine ◽

H1n1 Influenza Virus ◽

Influenza A H1n1

ABSTRACT Human influenza pandemics occur when influenza viruses to which the population has little or no immunity emerge and acquire the ability to achieve human-to-human transmission. In April 2009, cases of a novel H1N1 influenza virus in children in the southwestern United States were reported. It was retrospectively shown that these cases represented the spread of this virus from an ongoing outbreak in Mexico. The emergence of the pandemic led to a number of national vaccination programs. Surprisingly, early human clinical trial data have shown that a single dose of nonadjuvanted pandemic influenza A (H1N1) 2009 monovalent inactivated vaccine (pMIV) has led to a seroprotective response in a majority of individuals, despite earlier studies showing a lack of cross-reactivity between seasonal and pandemic H1N1 viruses. Here we show that previous exposure to a contemporary seasonal H1N1 influenza virus and to a lesser degree a seasonal influenza virus trivalent inactivated vaccine is able to prime for a higher antibody response after a subsequent dose of pMIV in ferrets. The more protective response was partially dependent on the presence of CD8+ cells. Two doses of pMIV were also able to induce a detectable antibody response that provided protection from subsequent challenge. These data show that previous infection with seasonal H1N1 influenza viruses likely explains the requirement for only a single dose of pMIV in adults and that vaccination campaigns with the current pandemic influenza vaccines should reduce viral burden and disease severity in humans.

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Classical swine H1N1 influenza viruses confer cross protection from swine-origin 2009 pandemic H1N1 influenza virus infection in mice and ferrets

Virology ◽

10.1016/j.virol.2010.09.009 ◽

2010 ◽

Vol 408 (1) ◽

pp. 128-133 ◽

Cited By ~ 23

Author(s):

Ji-Young Min ◽

Grace L Chen ◽

Celia Santos ◽

Elaine W Lamirande ◽

Yumiko Matsuoka ◽

...

Keyword(s):

Influenza Virus ◽

Virus Infection ◽

Influenza Virus Infection ◽

H1n1 Influenza ◽

Influenza Viruses ◽

Cross Protection ◽

Pandemic H1n1 ◽

H1n1 Influenza Virus ◽

Pandemic H1n1 Influenza

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Host DNA released by NETosis in neutrophils exposed to seasonal H1N1 and highly pathogenic H5N1 influenza viruses

10.21203/rs.2.24164/v1 ◽

2020 ◽

Author(s):

Louisa L.Y. Chan ◽

John M. Nicholls ◽

J.S. Malik Peiris ◽

Yu Lung Lau ◽

Michael C.W. Chan ◽

...

Keyword(s):

Influenza Virus ◽

Virus Infection ◽

H1n1 Virus ◽

Influenza Virus Infection ◽

Alveolar Epithelium ◽

Influenza Viruses ◽

H5n1 Influenza Virus ◽

H5n1 Influenza ◽

Influenza H1n1

Abstract Background Neutrophil (Nϕ) is of the most abundant number in human immune system. During acute influenza virus infection, Nϕs are already active in the early phase of inflammation-a time in which clinical biopsy or autopsy material is not readily available. However, the role of Nϕ in virus infection is not well understood. Here, we studied the role of Nϕ in host defense during influenza A virus infection, specifically assessing if it contributes to the differential pathogenesis in H5N1 disease. Methods Nϕs were freshly isolated from healthy volunteers and subjected to direct influenza H1N1 and H5N1 virus infection in vitro . The ability of the naïve Nϕs to infiltrate from the basolateral to the apical phase of the influenza virus infected alveolar epithelium was assessed. The viral replication, innate immune responses and Neutrophil extracellular trap (NET) formation of Nϕs upon influenza virus infection were evaluated. Results Our results demonstrated that influenza virus infected alveolar epithelium allowed more Nϕs transmigration. Significantly more Nϕs migrated across the H5N1 influenza virus infected the epithelium than the counterpart infected by the seasonal influenza H1N1 virus infected. Nϕs were equally susceptible to H5N1 and H1N1 virus infection with similar viral gene transcription. Productive replication was observed in H5N1 infected Nϕs. Both H5N1 and H1N1 infected Nϕs induced cytokines and chemokines including TNF-α, IFN-β, CXCL10, MIP-1α and IL-8. This inferred a more intense inflammatory response posed by H5N1 than H1N1 virus. Strikingly, NADPH oxidase-independent NET formation was observed in H1N1 infected Nϕs at 6 hpi while no NET formation was observed upon H5N1 infection. Conclusion Our data is the first to demonstrate that NET formation is abrogated in H5N1 influenza virus infection. Its contribution to the differential severity of H5N1 disease requires further investigation.

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Seasonal H1N1 2007 influenza virus infection is associated with elevated pre‐exposure antibody titers to the 2009 pandemic influenza A (H1N1) virus

Clinical Microbiology and Infection ◽

10.1111/j.1469-0691.2010.03352.x ◽

2011 ◽

Vol 17 (5) ◽

pp. 732-737 ◽

Cited By ~ 13

Author(s):

M. Lemaitre ◽

M. Leruez‐Ville ◽

X.N. De Lamballerie ◽

N. Salez ◽

P. Garrone ◽

...

Keyword(s):

Influenza Virus ◽

Virus Infection ◽

Pandemic Influenza ◽

Influenza A ◽

H1n1 Virus ◽

Influenza Virus Infection ◽

Influenza A H1n1 ◽

Antibody Titers

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Influenza-induced thrombocytopenia is dependent on the subtype and sialoglycan receptor and increases with virus pathogenicity

Blood Advances ◽

10.1182/bloodadvances.2020001640 ◽

2020 ◽

Vol 4 (13) ◽

pp. 2967-2978 ◽

Cited By ~ 4

Author(s):

A. J. Gerard Jansen ◽

Thom Spaan ◽

Hui Zhi Low ◽

Daniele Di Iorio ◽

Judith van den Brand ◽

...

Keyword(s):

Influenza Virus ◽

Platelet Count ◽

Virus Infection ◽

Influenza A ◽

H1n1 Virus ◽

Acute Infection ◽

Influenza Virus Infection ◽

Hepatic Clearance ◽

H3n2 Virus ◽

Influenza A H1n1

Abstract Thrombocytopenia is a common complication of influenza virus infection, and its severity predicts the clinical outcome of critically ill patients. The underlying cause(s) remain incompletely understood. In this study, in patients with an influenza A/H1N1 virus infection, viral load and platelet count correlated inversely during the acute infection phase. We confirmed this finding in a ferret model of influenza virus infection. In these animals, platelet count decreased with the degree of virus pathogenicity varying from 0% in animals infected with the influenza A/H3N2 virus, to 22% in those with the pandemic influenza A/H1N1 virus, up to 62% in animals with a highly pathogenic A/H5N1 virus infection. This thrombocytopenia is associated with virus-containing platelets that circulate in the blood. Uptake of influenza virus particles by platelets requires binding to sialoglycans and results in the removal of sialic acids by the virus neuraminidase, a trigger for hepatic clearance of platelets. We propose the clearance of influenza virus by platelets as a paradigm. These insights clarify the pathophysiology of influenza virus infection and show how severe respiratory infections, including COVID-19, may propagate thrombocytopenia and/or thromboembolic complications.

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