title: Early IL-4 gene expression in abomasum is associated with resistance to Haemonchus contortus in hair and wool sheep breeds.
abstract: Early immune events associated with reduced larval burden remain unclear in parasite-resistant breeds of sheep. Therefore, our objective was to determine breed differences in immune-related gene expression following infection with H. contortus. Gene expression in abomasal tissue and mucosa and in abomasal lymph nodes (ALN) was measured in 24 St. Croix (hair) lambs and 24 Dorset x (Finn-Rambouillet) (wool) lambs at 0 (uninfected), 3, 5 and 7 days after infection with 10 000 L3 H. contortus larvae. Expression of IL-4 in abomasal mucosa was detected on day 3 and increased to day 7 in hair lambs, but was not detectable in wool lambs. Genes that recruit neutrophils (CXCL1) and macrophages (MCP1) were upregulated in abomasal mucosa of hair lambs. Genes associated with alternative macrophage activation (ARG-1) and eosinophil activation (Gal-14) were also upregulated in the abomasal mucosa of hair lambs. Tissue remodeling genes (MMP13, PDGF) and tumour necrosis factor alpha (TNF-α) and MCP1 were upregulated in abomasal tissue of wool lambs; these lambs also had greater expression of forkhead box P3 in ALN. These data indicate a role for early IL-4 expression locally and demonstrate potential downregulation of immunity in wool sheep that could facilitate establishment of H. contortus.
authors.affiliation: Division of Animal and Nutritional Sciences, West Virginia University, Morgantown, WV, USA.
authors.forename: J R
authors.initials: JR
authors.lastname: Jacobs
authors.affiliation: Division of Animal and Nutritional Sciences, West Virginia University, Morgantown, WV, USA.
authors.forename: K N
authors.initials: KN
authors.lastname: Sommers
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia Tech, Blacksburg, VA, USA.
authors.forename: A M
authors.initials: AM
authors.lastname: Zajac
authors.affiliation: Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA, USA.
authors.forename: D R
authors.initials: DR
authors.lastname: Notter
authors.affiliation: Division of Animal and Nutritional Sciences, West Virginia University, Morgantown, WV, USA.
authors.forename: S A
authors.initials: SA
authors.lastname: Bowdridge
mesh_terms: D000018:Abomasum / Q000276:immunology / Q000469:parasitology*; D000818:Animals; D001947:Breeding; D005243:Feces / Q000469:parasitology; D006188:Haemonchiasis / Q000235:genetics / Q000276:immunology / Q000469:parasitology / Q000662:veterinary*; D006189:Haemonchus / Q000276:immunology* / Q000502:physiology; D006790:Host-Parasite Interactions; D015847:Interleukin-4 / Q000235:genetics* / Q000276:immunology; D012756:Sheep; D012757:Sheep Diseases / Q000235:genetics* / Q000276:immunology / Q000469:parasitology
chemical_list: D015847:Interleukin-4
keywords: Haemonchus contortus; St. Croix sheep; Th2 immunity