Genome-wide mRNA expression profiles induced by infection with the pandemic and seasonal influenza A viruses in macrophages

Infection with pandemic A/H1N1 influenza virus induces high levels of circulating and lung pro-inflammatory cytokines and chemokines in experimental models and humans. These inflammatory mediators contribute to poor clinical outcomes of this infection. To compare the regulation of inflammatory responses in seasonal versus pandemic influenza A virus infections, we analyzed the expression of mRNA by the human gene st 1.0 array (affymetrix). We identifed a number of differentially expressed genes by infection of the A/H1N1 compared to the seasonal virus. Gene ontology analysis of these genes found that most of them are involved in several aspects of immunity. These studies suggest that factors inherent in the pandemic A/H1N1 viral strain may augment the production of inflammatory mediators by inhibiting SOCS- 1 expression and that infection with this viral strain also modifies the expression of several immunity related genes and pathways .

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