title: Role of the NOD1/NF-κB pathway on bovine neutrophil responses to crude lipopolysaccharide.
abstract: Cytosolic nucleotide oligomerisation domain (NOD)-like receptors play an important role in host defence against infection. Reduced NOD1 expression has been observed in dysfunctional neutrophils derived from periparturient cattle known to be most susceptible to coliform mastitis. However, whether impairment of NOD1 suppresses the immune responses of bovine neutrophils during bacterial infections remains unknown. Crude (phenol extracted) lipopolysaccharide (cLPS), which often contains other immunostimulatory molecules, including NOD1 agonist, is known to induce almost the whole bacterial response. This study was conducted to explore the role of NOD1/nuclear factor (NF)-κB pathway in the cytokine and functional responses of bovine neutrophils challenged with Escherichia coli-derived cLPS. Freshly isolated blood neutrophils from healthy heifers were pre-incubated for 2 h with ML130, a selective inhibitor of NOD1/NF-κB pathway. Cells were then exposed to cLPS for additional 4 h. Inhibition of the NOD1/NF-κB pathway resulted in a decrease in cLPS-induced phosphorylation of the inhibitor of NF-κBα (IκBα) in neutrophils. Impairment of the NOD1/NF-κB pathway tended to down-regulate mRNA levels of pro-inflammatory cytokines interleukin (IL)-1β and tumour necrosis factor (TNF)-α, chemokines IL-8 and C-X-C motif ligand 2 (CXCL2), and adhesion molecules CD11b and CD62L, in cLPS-challenged cells. Functional analyses showed that blocking the NOD1/NF-κB pathway inhibited neutrophil migration and phagocytic killing capacity, and promoted neutrophil death upon cLPS stimulation. The data presented here demonstrate that activation of NOD1/NF-κB pathway contributes to the functional responses of neutrophils to cLPS.
authors.affiliation: Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, 866 Yuhangtang Rd., Hangzhou 310058, China.
authors.forename: Liang-Jun
authors.initials: LJ
authors.lastname: Wei
authors.affiliation: Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, 866 Yuhangtang Rd., Hangzhou 310058, China. Electronic address: tanxun@zju.edu.cn.
authors.forename: Xun
authors.initials: X
authors.lastname: Tan
authors.affiliation: Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, 866 Yuhangtang Rd., Hangzhou 310058, China.
authors.forename: Guo-Juan
authors.initials: GJ
authors.lastname: Fan
authors.affiliation: Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, 866 Yuhangtang Rd., Hangzhou 310058, China.
authors.forename: Ya-Nan
authors.initials: YN
authors.lastname: Jiang
authors.affiliation: Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, 866 Yuhangtang Rd., Hangzhou 310058, China.
authors.forename: Qurban A
authors.initials: QA
authors.lastname: Shah
mesh_terms: D000818:Animals; D002417:Cattle / Q000276:immunology*; D002465:Cell Movement; D002470:Cell Survival; D016207:Cytokines / Q000276:immunology*; D004926:Escherichia coli / Q000737:chemistry; D005786:Gene Expression Regulation; D008070:Lipopolysaccharides / Q000494:pharmacology*; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism; D009504:Neutrophils / Q000276:immunology*; D053474:Nod1 Signaling Adaptor Protein / Q000235:genetics / Q000378:metabolism; D010587:Phagocytosis; D015398:Signal Transduction / Q000276:immunology
chemical_list: D016207:Cytokines; D008070:Lipopolysaccharides; D016328:NF-kappa B; D053474:Nod1 Signaling Adaptor Protein
keywords: Bovine; Cytosolic nucleotide oligomerisation domain 1; Immune response; Neutrophils