Proteomic analysis of the lungs of mice infected with different pathotypes of H5N1 avian influenza viruses

Abstract

The virulence of influenza virus is determined by viral and host factors. Data on the genetic basis of the virulence of H5N1 influenza viruses have increased over the past decade; however, the contributions of host factors to the outcomes of H5N1 infection remain largely unknown. Here, we tested two chicken H5N1 viruses in mice and found that A/chicken/VN1214/2007 was nonlethal in mice and only replicated in the lung, whereas A/chicken/VN1180/2006 was highly lethal and replicated systemically in mice. To investigate the host response against these two different virus infections, we performed proteomic analysis by using 2D DIGE on the lung tissues of mice collected on days 1 and 3 postinoculation with different viruses or PBS as a control. Thirty-nine differentially expressed (DE) proteins related to "immune and stimulus response," "macromolecular biosynthesis and metabolism," and "cellular component and cytoskeleton" were identified in the virus-inoculated groups. Moreover, 13 DE proteins were identified between the two virus-inoculated groups, implying that these proteins may play important roles in the different outcomes of infection with these two viruses. Our data provide important information regarding the host response to mild and lethal H5N1 influenza virus infection.

Glycosylation of the Hemagglutinin Protein of H5N1 Influenza Virus Increases Its Virulence in Mice by Exacerbating the Host Immune Response

“…By using two HPAI H5N1 viruses (CK/1180 and CK/1214) with similar genomes but different pathogenicities in mice (31, 32), in this study, we demonstrated that a single amino acid mutation at position 158 of the HA protein had fundamental effect on the systemic replication and pathogenicity of these H5N1 influenza viruses in mice. We further found that the substitution G158N introduced an N-linked glycosylation at positions 158 to 160 of the HA protein and that this N-linked glycosylation enhanced viral productivity in infected mammalian cells and exacerbated host immune and inflammatory responses to viral infection.…”

“…In our previous studies (31, 32), we characterized the pathogenicity and viral replication of CK/1180 and CK/1214 in mice and found that CK/1180 systemically replicated and showed high pathogenicity in mice, with a 50% mouse lethal dose (MLD 50 ) of 2.5 log 10 50% egg infectious doses (EID 50 ), but CK/1214 replicated only in lung tissue and displayed low virulence in mice. In this study, we found that even 10 7 EID 50 of CK/1214 did not kill mice (MLD 50 > 7.5 log 10 EID 50 ) (Fig.…”

“…Previously, we characterized the genetic and biological diversity of HPAI H5N1 viruses in Vietnam (31), and found that two viruses, A/chicken/Vietnam-Bac Lieu/1214/2007 (CK/1214) and A/chicken/Vietnam-Ca Mau/1180/2006 (CK/1180), shared similar genetic backgrounds, belonging to the same genotype, but displayed substantially different levels of virulence in mice (31, 32). In the present study, we used reverse genetics to identify the molecular determinants for the different virulence of these two viruses in mice and explored the possible underlying mechanisms.…”

Molecular Determinants of Virulence and Stability of a Reporter-Expressing H5N1 Influenza A Virus

“…Enhanced chemiluminescence (ECL) anti-mouse IgG horseradish peroxidase-linked whole antibody (from sheep) was purchased from GE Healthcare. Western blotting was performed as described previously (16). Briefly, the samples were lysed with 2ϫ SDS loading buffer (Invitrogen) and subjected to SDS-polyacrylamide gel electrophoresis (SDS-PAGE).…”

Proteome Response of Chicken Embryo Fibroblast Cells to Recombinant H5N1 Avian Influenza Viruses with Different Neuraminidase Stalk Lengths

“…Some proteomic analyses had been performed against influenza virus-host models, however, these studies on host response to influenza virus infection primarily targeted human influenza viruses, specifically, only one infection period. For instance, quantitative proteomics has been applied to influenza-host interactions in cells10111213 and several proteomic studies have also been carried out in influenza virus infected animals1415.…”