Summary
The spread of infection in the chorioallantoic membrane (CAM) has been analysed with pathogenic and non-pathogenic avian influenza A viruses. After allantoic inoculation of pathogenic strains, high titers of infectious virus were found in the allantoic fluid, and virus growth could be demonstrated by immunohistology and electron microscopy in the allantoic epithelium, the mesenchyma, and in the chorionic epithelium. By the same route of inoculation, non-pathogenic strains yielded also high titers of infectious virus in the allantoic fluid, but virus replication was restricted to the allantoic epithelium and did not occur in the other cell layers. After chorionic inoculation of pathogenic strains, replication occurred in all layers of the CAM, and infectious virus was released into the allantoic fluid. However, when the chorionic epithelium was infected with a non-pathogenic strain, infection did not spread beyond the site of inoculation. These differences in virus spread are based on differential activation of the hemagglutinin by proteolytic cleavage. The hemagglutinin of pathogenic strains is cleaved in cells of each layer, whereas the hemagglutinin of non-pathogenic strains is cleaved only in the allantoic epithelium. In epithelial cells, virus budding occurred nearly exclusively at the apical side of the cell surface, but this polarization of virus maturation was found with both pathogenic and nonpathogenic strains, indicating that it does not account for the differences in virus spread and, thus, in pathogenicity.
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References
Becht, H.: Untersuchungen über die Biosynthese und den serologischen Nachweis des Ribonucleoproteid-Antigens von Influenzaviren. Z. Med. Mikrobiol. Immunol.156, 333–367 (1971).
Bosch, F., Orlich, M., Klenk, H.-D., Rott, R.: The structure of the hemagglutinin, a determinant for the pathogenicity of influenza viruses. Virology95, 191–207 (1979).
Boulan, E. R., Sabatini, D. D.: Asymmetric budding of viruses in epithelial monolayers: a model system for study of epithelial polarity. Proc. Natl. Acad. Sci. U.S.A.75, 5071–5075 (1978).
Burns, J.: Background staining and sensitivity of the unlabelled antibody-enzyme (PAP) method. Comparison with the peroxidase labelled antibody sandwich method using formalin fixed paraffin embedded material. Histochem.43, 291–294 (1975).
Flumerfeldt, B. A., Gibson, M. A.: The histology and histochemistry of the developing chorioallantoic membrane in the chick(Gallus domesticus). Canad. J. Zool.47, 323–331 (1969).
Fulton, F., Isaacs, A.: Influenza virus multiplication in the chick chorioallantoic membrane. J. gen. Microbiol.9, 119–131 (1953).
Gagel, C., Linder, M., Müller-Berghaus, G., Lasch, H. G.: Verbrauchskoagulopathie bei der Klassischen Geflügelpest. Ein Beitrag zur Pathogenese von Blutungen bei Virusinfektionen. Zbl. Vet. Med.B17, 410–417 (1970).
Graham, R. C., Karnovsky, M. J.: The early stages of adsorption of injected horseradish peroxidase in the proximal tubules of mouse kidney. Ultrastructural cytochemistry by a new technique. J. Histochem. Cytochem.14, 291–302 (1966).
Klenk, H.-D., Rott, R., Orlich, M.: Further studies on the activation of influenza virus by proteolytic cleavage. J. gen. Virol.36, 151–161 (1977).
Klenk, H.-D., Rott, R., Orlich, M., Blödorn, J.: Activation of influenza A viruses by trypsin treatment. Virology68, 426–439 (1975).
Lazarowitz, S. G., Choppin, P. W.: Enhancement of the infectivity of influenza A and B viruses by proteolytic cleavage of the hemagglutinin polypeptide. Virology68, 440–454 (1975).
Lennette, E. H., Schmidt, N. J.: Diagnostic procedures for viral and Rickettsial diseases. Americ. Public Health Assoc. Inc. 1964.
Murphy, J. S., Bang, F. B.: Observations with the electron microscope on cells of the chick chorio-allantoic membrane infected with influenza virus. J. exp. Med.95, 259–268 (1952).
Nagai, Y., Klenk, H.-D., Rott, R.: Proteolytic cleavage of the viral glycoproteins and its significance for the virulence of Newcastle disease virus. Virology72, 494–508 (1976).
Nagai, Y., Shimokata, K., Yoshida, T., Hamaguchi, M., Iinuma, M., Maeno, M., Matsumoto, T., Klenk, H.-D., Rott, R.: The spread of a pathogenic and an apathogenic strain of Newcastle disease virus in the chick embryo as depending on the protease sensitivity of the virus glycoproteins. J. gen. Virol.45, 263–272 (1979).
Rott, R.: Molecular basis of infectivity and pathogenicity of myxoviruses. Arch. Virol.59, 285–298 (1979).
Webster, R. G., Yakhano, M., Hinshaw, V. S., Bean, W. J., Murti, K. G.: Intestinal influenza: Replication and characterization of influenza viruses in ducks. Virology84, 268–278 (1978).
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Rott, R., Reinacher, M., Orlich, M. et al. Cleavability of hemagglutinin determines spread of avian influenza viruses in the chorioallantoic membrane of chicken embryo. Archives of Virology 65, 123–133 (1980). https://doi.org/10.1007/BF01317323
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DOI: https://doi.org/10.1007/BF01317323