Submitted to: International Symposium on Avian Influenza
Publication Type: Abstract Only
Publication Acceptance Date: January 28, 2009
Publication Date: April 5, 2009
Citation: Pantin Jackwood, M.J., Kapczynski, D.R., Sarmento, L., Wasilenko, J.L., Afonso, C.L. 2009. Role of immune-related host gene responses in the pathobiology of H5N1 highly pathogenic avian influenza in ducks [abstract]. 7th International Symposium on Avian Influenza, April 5-9, 2009, Athens, Georgia. p. 43. Technical Abstract: The Asian highly pathogenic avian influenza (HPAI) H5N1 viruses have changed from producing mild respiratory infections in ducks to some strains causing severe disease and mortality. In this study we examined host response to infection with HPAI H5N1 viruses in ducks. With the use of a whole genome chicken 60-mer oligonucleotide 44K microarray we analyzed the transcriptional profiles of ducks infected with two HPAI H5N1 viruses that have different pathogenicity in ducks. This permitted the identification of genes differentially expressed in spleens of ducks after infection with these viruses. Semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) or real-time quantative RT-PCR was used to confirm the microarray results and to determine the expression of cytokines that were not detected by the microarray analysis because of lack of similarity between duck and chicken gene sequences. Tissues collected from ducks of different age and species infected with other HPAI viruses were also analyzed. An important number of differentially expressed genes associated with infection were detected, demonstrating the complexity of the patterns of gene expression in ducks in response to HPAI. Among the genes commonly up-regulated after HPAI infection were IL-1b and IL-6 (pro-inflammatory interleukins), RANTES, MIP-1b, MIP-3b (chemokines), and MX1. Other genes were expressed differently depending on the virus used, and the age and species of the ducks, like IL-2, IL-4, IL-8, IL-18 and interferons alpha and gamma. The results obtained illustrate the interplay between the virus and the response of the host to infection and how both modulate and affect the pathogenesis of avian influenza. Different mechanisms are potentially induced by avian influenza viruses to modulate the host response to infection. On the other hand, the host response will vary depending on the age and species of bird.