title: Immune gene expression in the spleen of chickens experimentally infected with Ascaridia galli.
abstract: Ascaridia galli is a gastrointestinal nematode infecting chickens. Chickens kept in alternative rearing systems or at free-range experience increased risk for infection with resulting high prevalences. A. galli infection causes reduced weight gain, decreased egg production and in severe cases increased mortality. More importantly, the parasitised chickens are more susceptible to secondary infections and their ability to develop vaccine-induced protective immunity against other diseases may be compromised. Detailed information about the immune response to the natural infection may be exploited to enable future vaccine development. In the present study, expression of immune genes in the chicken spleen during an experimental infection with A. galli was investigated using the Fluidigm(®) BioMark™ microfluidic qPCR platform which combines automatic high-throughput with attractive low sample and reagent consumption. Spleenic transcription of immunological genes was compared between infected chickens and non-infected controls at week 2, 6, and 9 p.i. corresponding to different stages of parasite development/maturation. At week 2 p.i. increased expression of IL-13 was observed in infected chickens. Increased expression of MBL, CRP, IFN-α, IL-1β, IL-8, IL-12β and IL-18 followed at week 6 p.i. and at both week 6 and 9 p.i. expression of DEFβ1 was highly increased in infected chickens. In summary, apart from also earlier reported increased expression of the Th2 signature cytokine IL-13 we observed only few differentially expressed genes at week 2 p.i. which corresponds to the larvae histotrophic phase. In contrast, we observed increased expression of pro-inflammatory cytokines and acute phase proteins in infected chickens, by week 6 p.i. where the larvae re-enter the intestinal lumen. Increased expression of DEFβ1 was observed in infected chickens at week 6 p.i. but also at week 9 p.i. which corresponds to a matured stage where adult worms are present in the intestinal lumen.
authors: Department of Animal Science, Aarhus University, Blichers Alle 20, DK-8830 Tjele, Denmark. Electronic address: Tina.Dalgaard@anis.au.dk.
authors: Tina S
authors: TS
authors: Dalgaard
authors: National Veterinary Institute, Division of Veterinary Diagnostics and Research, Technical University of Denmark, Bülowsvej 27, DK-1870 Frederiksberg C, Denmark.
authors: Kerstin
authors: K
authors: Skovgaard
authors: Department of Animal Science, Aarhus University, Blichers Alle 20, DK-8830 Tjele, Denmark.
authors: Liselotte R
authors: LR
authors: Norup
authors: Department of Animal Science, Aarhus University, Blichers Alle 20, DK-8830 Tjele, Denmark.
authors: Janne
authors: J
authors: Pleidrup
authors: National Food Institute, Technical University of Denmark, Mørkhøj Bygade 19, DK-2860 Søborg, Denmark.
authors: Anders
authors: A
authors: Permin
authors: Department of Environment and Toxicology, DHI, Agern Allé 5, DK-2970 Hørsholm, Denmark.
authors: Torben W
authors: TW
authors: Schou
authors: National Veterinary Institute, Division of Veterinary Diagnostics and Research, Technical University of Denmark, Bülowsvej 27, DK-1870 Frederiksberg C, Denmark.
authors: Dorte F
authors: DF
authors: Vadekær
authors: National Veterinary Institute, Division of Veterinary Diagnostics and Research, Technical University of Denmark, Bülowsvej 27, DK-1870 Frederiksberg C, Denmark.
authors: Gregers
authors: G
authors: Jungersen
authors: Department of Animal Science, Aarhus University, Blichers Alle 20, DK-8830 Tjele, Denmark.
authors: Helle R
authors: HR
authors: Juul-Madsen
mesh_terms: D000209:Acute-Phase Proteins / Q000235:genetics / Q000276:immunology; D000818:Animals; D001197:Ascaridia / Q000276:immunology* / Q000472:pathogenicity*; D001198:Ascaridiasis / Q000235:genetics / Q000276:immunology / Q000662:veterinary; D030161:Avian Proteins / Q000235:genetics / Q000276:immunology; D002645:Chickens / Q000235:genetics / Q000276:immunology* / Q000469:parasitology*; D016207:Cytokines / Q000235:genetics / Q000276:immunology; D023082:Defensins / Q000235:genetics / Q000276:immunology; D005260:Female; D020869:Gene Expression Profiling; D054884:Host-Pathogen Interactions / Q000235:genetics / Q000276:immunology; D008297:Male; D011201:Poultry Diseases / Q000235:genetics / Q000276:immunology / Q000469:parasitology; D013154:Spleen / Q000276:immunology*; D013997:Time Factors
chemical_list: D000209:Acute-Phase Proteins; D030161:Avian Proteins; D016207:Cytokines; D023082:Defensins
keywords: Ascaridia galli; Chickens; Immune gene expression; Microfluidic qPCR; Nematodes; Systemic immune response