Decrease of virus receptors during highly pathogenic H5N1 virus infection in humans and other mammals
Debby van Riel1, Lonneke M Leijten1, George Kochs2
1Department of Viroscience, Erasmus MC, Rotterdam, The Netherlands.
The American Journal of Pathology
|September 3, 2013
Summary
Highly pathogenic avian influenza H5N1 virus receptor levels decrease in infected lung cells across species. This reduction, linked to interferon activity, may be a defense mechanism limiting viral spread in the lower respiratory tract.
Area of Science:
- Virology
- Immunology
- Pathology
Background:
- Highly pathogenic avian influenza H5N1 virus causes severe pneumonia in humans.
- H5N1 virus receptor distribution in normal respiratory tracts is known, but not during active infection.
- Alveolar receptors are crucial for understanding H5N1 pathogenesis.
Purpose of the Study:
- To investigate the distribution of H5N1 virus receptors in alveolar tissues during H5N1 infection.
- To compare receptor changes across different species (humans, macaques, ferrets, cats).
- To correlate receptor changes with host immune responses.
Main Methods:
- Virus histochemistry
- Lectin histochemistry
- Analysis of alveolar tissues from infected humans, macaques, ferrets, and cats.
Main Results:
- A decrease in H5N1 virus receptors was observed in infected and adjacent cells in all studied species.
- This receptor downregulation was associated with the presence of MxA, an interferon activity marker.
- Findings suggest a species-wide response to H5N1 infection.
Conclusions:
- The observed decrease in H5N1 virus receptors during infection may represent an innate defense mechanism.
- This downregulation could limit viral replication in the lower respiratory tract.
- Further research into this mechanism could inform therapeutic strategies against avian influenza.
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