Project description:Actinobacillus pleuropneumoniae is the etiologic agent of contagious pleuropneumonia, an economically important disease of commercially reared swine throughout the world. To cause this disease, A. pleuropneumoniae must rapidly overcome porcine pulmonary innate immune defenses. Effects of koromycin, an antimicrobial agent that acts as an noncompetitive inhibitor of the interaction of NQR with its quinone substrate, on the transcriptome of A. pleuropneumoniae was investigated.
Project description:Swine H1N1 influenza virus and streptococcus suis serotype 2 (SS2) are two important contributors to the porcine respiratory disease complex, which have significant economic impacts. Clinically, swine influenza virus and swine streptococcus suis co-infection is common, which will increase the mortality. However, the pathogenesis of the co-infection remains largely unkown. To explore it, gene expression profiling was to performed to detect comprehensive analysis of the global host response induced by H1N1 virus infection alone, SS2 infection alone, H1N1-SS2 co-infection and PBS control.
Project description:Background: Swine influenza is a highly contagious viral infection in pigs affecting the respiratory tract that can have significant economic impacts. Streptococcus suis serotype 2 is one of the most important post-weaning bacterial pathogens in swine causing different infections, including pneumonia. Both pathogens are important contributors to the porcine respiratory disease complex. Outbreaks of swine influenza virus with a significant level of co-infections due to S. suis have lately been reported. In order to analyze a global response to the dual infection, we carried out a comprehensive gene expression profiling using a microarray approach to study the swine tracheal epithelial (NPTr) cell response to a co-infection with H1N1 swine influenza virus (swH1N1) and S. suis serotype 2. Results: Gene clustering showed that the swH1N1 and swH1N1/S. suis infections modified the expression of genes in a similar manner. Additionally, infection of NPTr cells by S. suis alone did not result in many differentially expressed genes compared to mock-infected cells. However, some important genes coding for inflammatory mediators, such as chemokines, interleukins, cell adhesion molecules and eicosanoids, were significantly upregulated in the presence of both pathogens comparing to infection with each pathogen taken individually. This synergy may also be the consequence of an increased adhesion/invasion of epithelial cells previously infected by swH1N1, as recently reported. Conclusion: In a co-infection situation, influenza virus would replicate in the respiratory epithelium inducing an inflammatory infiltrate comprised of mononuclear cells and neutrophils. Despite that these cells are unable to phagocyte and kill S. suis, they are highly activated by this pathogen. S. suis is not considered a primary pulmonary pathogen, but an exacerbated production of pro-inflammatory mediators during a co-infection with influenza virus may be of critical importance in the pathogenesis and outcome of this respiratory disease complex.
