title: Transcriptional profiling of chicken immunity-related genes during infection with Avibacterium paragallinarum.
abstract: Avibacterium paragallinarum is the causative agent of Infectious Coryza (IC), which is an upper respiratory tract disease in chickens. The occurrence of outbreaks has emphasized the significance of the disease globally in the chicken industry. Studies have demonstrated that early immune responses are critical in defining the severity and physiological outcome of an infection. This prompted the need to investigate the regulation of immune functions by the number of genes that are expressed during the chickens' response to A. paragallinarum serovar C3 insult. This study consisted of 15 male leghorn birds that were scored into groups (score 1, 2, 3) according to severity of symptoms after they were challenged. Expression patterns of immunity-related genes were followed as symptoms progressed from a disease score of 1 to 3. The data proposed that initial pathogen recognition was either through Toll-like receptors 2 or 4. Unique expression patterns were observed such as the up-regulation of TLR7 which recognizes viral-like particles. This substantiated the presence of prophages reported in the genome of A. paragallinarum. Significant down-regulation of metabolic pathways was observed, which led us to hypothesize that the host may rely on an oxidative stress response as initial immune response. The data sheds light onto the mechanisms that govern the immune system towards infection and/or towards the initial response to infections with highly virulent A. paragallinarum.
authors.affiliation: Faculty of Natural and Agricultural Science, Department of Microbial, Biochemical and Food Biotechnology, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa. Electronic address: boucherce@ufs.ac.za.
authors.forename: Charlotte E
authors.initials: CE
authors.lastname: Boucher
authors.affiliation: Faculty of Natural and Agricultural Science, Department of Microbial, Biochemical and Food Biotechnology, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa.
authors.forename: Chrispian W
authors.initials: CW
authors.lastname: Theron
authors.affiliation: Faculty of Natural and Agricultural Science, Department of Microbial, Biochemical and Food Biotechnology, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa.
authors.forename: Arina C
authors.initials: AC
authors.lastname: Jansen
authors.affiliation: Faculty of Natural and Agricultural Science, Department of Microbial, Biochemical and Food Biotechnology, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa.
authors.forename: Robert R
authors.initials: RR
authors.lastname: Bragg
mesh_terms: D000818:Animals; D030161:Avian Proteins / Q000235:genetics / Q000276:immunology; D002645:Chickens / Q000235:genetics / Q000276:immunology; D015536:Down-Regulation; D020869:Gene Expression Profiling; D006192:Haemophilus Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary*; D044134:Haemophilus paragallinarum / Q000145:classification / Q000276:immunology / Q000472:pathogenicity; D007113:Immunity, Innate / Q000235:genetics; D008297:Male; D016871:Pasteurellaceae Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary*; D011201:Poultry Diseases / Q000235:genetics* / Q000276:immunology*; D012141:Respiratory Tract Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary*; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology; D051193:Toll-Like Receptors / Q000235:genetics / Q000276:immunology; D015854:Up-Regulation
chemical_list: D030161:Avian Proteins; D051193:Toll-Like Receptors
keywords: Immune response; Immunity-related genes; Infectious Coryza; Oxidative stress response; Toll-like receptors