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Measuring Influenza Neutralizing Antibody Responses to A(H3N2) Viruses in Human Sera by Microneutralization Assays Using MDCK-SIAT1 Cells
Published on: November 22, 2017
Variation and infectivity neutralization in influenza.
Marcel Knossow1, John J Skehel
1CNRS Laboratoire d'Enzymologie et Biochimie Structurales, Gif sur Yvette Cedex, France.
Immunology
|August 24, 2006
Summary
Influenza epidemics arise from avian viruses with novel haemagglutinin (HA) glycoproteins. Understanding HA structural changes is key to preventing future human-to-human viral transmission and pandemics.
Area of Science:
- Virology
- Structural Biology
- Immunology
Background:
- Influenza pandemics originate from avian viruses possessing haemagglutinin (HA) glycoproteins novel to humans.
- Human immunity is absent against these foreign HA subtypes, facilitating widespread epidemics.
- Anti-HA antibodies are crucial for neutralizing influenza virus infectivity.
Purpose of the Study:
- To review structural differences among avian HA subtypes (H1-H16).
- To describe HA structural modifications enabling human transmission of avian influenza viruses.
- To assess potential changes for current avian H5 virus human-to-human spread.
Main Methods:
- Comparative structural analysis of haemagglutinin (HA) glycoproteins from avian influenza viruses.
- Review of historical pandemic data (1918, 1957, 1968) focusing on HA structural adaptations.
- Assessment of potential structural alterations for novel avian influenza virus strains.
Main Results:
- Detailed outline of structural distinctions among 16 avian HA subtypes.
- Description of specific HA structural changes facilitating human adaptation for H1, H2, and H3 subtypes during past pandemics.
- Identification of potential structural requirements for human-to-human transmission of avian H5 viruses.
Conclusions:
- Structural variations in avian haemagglutinin (HA) glycoproteins influence their potential to cause human pandemics.
- Understanding HA structural evolution is critical for predicting and preventing future influenza outbreaks.
- Targeted analysis of HA structure provides insights into viral adaptation and pandemic risk assessment.
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