Highly pathogenic H5N1 influenza A virus spreads efficiently in human primary monocyte-derived dendritic cells and macrophages Veera Westenius1,*, Sanna M. Mäkelä1, Ilkka Julkunen2 and Pamela Österlund1 1Expert Microbiology Unit, Department of Health Security, National Institute for Health and Welfare, Helsinki, Finland; 2Department of Virology, University of Turku, Turku, Finland * Corresponding author
As a zoonotic reservoir, avian-origin influenza A viruses pose a constant threat to humans. Mortality among humans in the highly pathogenic avian influenza (HPAI) H5N1 virus infection is even 60%. Despite intense research there are still open questions in the pathogenicity of the H5N1 virus in humans. To characterize the H5N1 virus infection in human monocyte-derived macrophages and dendritic cells we used human isolates of highly pathogenic H5N1/2004 and low pathogenic H7N9/2013 avian influenza viruses in comparison with a seasonal H3N2/1989 virus. We observed that the H5N1 virus has an overwhelming ability to grow in primary human cells and even added trypsin did not equalize the infectivity between the strains. We also noticed that H5N1 virus particles were more often propagation-competent than H7N9 or H3N2 virions, and in human dendritic cells and macrophages H5N1 infection produced new infective virus particles whereas H3N2 or H7N9 infections faded away. Interestingly, the H5N1 virus was capable to spread efficiently through the whole cell culture despite the simultaneous strong interferon response, which might in part explain the fatal outcome of a H5N1 virus infection.
Credits: None available.
You must be logged in and own this product in order to post comments.