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10:32
A Miniaturized Glycan Microarray Assay for Assessing Avidity and Specificity of Influenza A Virus Hemagglutinins
Published on: May 29, 2016
Changes in H3 influenza A virus receptor specificity during replication in humans
K Ryan-Poirier1, Y Suzuki, W J Bean
1Department of a Virology and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
Virus Research
|October 23, 1998
Summary
Influenza A H3 viruses evolved in humans, changing their sensitivity to pig and rabbit serum inhibitors over time. This adaptation reflects molecular evolution and host tropism shifts since their avian origin.
Area of Science:
- Virology
- Molecular Evolution
- Immunology
Background:
- The 1968 Hong Kong pandemic was caused by Influenza A H3 subtype viruses originating from avian reassortment.
- Hemagglutinin (HA) receptor specificity and serum inhibitor sensitivity are linked to influenza virus host species.
- Human H3 viruses prefer Neu5Acalpha2,6Gal receptors and are serum-sensitive, unlike avian/equine viruses (Neu5Acalpha2,3Gal, serum-resistant).
Purpose of the Study:
- To investigate the evolutionary changes in receptor specificity and serum inhibitor sensitivity of H3 influenza A viruses in humans.
- To understand the mechanisms of viral molecular evolution and host tropism.
- To track changes since the introduction of H3 HA into the human population.
Main Methods:
- Analysis of receptor specificity and serum inhibitor sensitivity of historical H3 influenza A virus isolates.
- Testing neutralization and hemagglutination inhibition with various animal sera (horse, pig, rabbit).
Main Results:
- All tested H3 viruses were sensitive to horse serum neutralization and inhibition.
- Early H3 viruses (pre-1977) were resistant to pig and rabbit serum inhibitors.
- Post-1977 H3 viruses became uniformly sensitive to pig and rabbit serum inhibitors.
- Receptor linkage recognition (Neu5Acalpha2,3Gal vs. Neu5Acalpha2,6Gal) did not correlate with serum sensitivity changes.
Conclusions:
- The receptor specificity of H3 influenza A virus hemagglutinin, specifically its inhibitor sensitivity, has demonstrably changed during human adaptation.
- These evolutionary changes in H3 HA occurred after its introduction from an avian source.
- The study provides insights into viral adaptation and host switching mechanisms.
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