title: Comparison of innate immune agonists for induction of tracheal antimicrobial peptide gene expression in tracheal epithelial cells of cattle.
abstract: Bovine respiratory disease is a complex of bacterial and viral infections of economic and welfare importance to the beef industry. Although tracheal antimicrobial peptide (TAP) has microbicidal activity against bacterial pathogens causing bovine respiratory disease, risk factors for bovine respiratory disease including BVDV and stress (glucocorticoids) have been shown to inhibit the induced expression of this gene. Lipopolysaccharide is known to stimulate TAP gene expression, but the maximum effect is only observed after 16 h of stimulation. The present study investigated other agonists of TAP gene expression in primary cultures of bovine tracheal epithelial cells. PCR analysis of unstimulated tracheal epithelial cells, tracheal tissue and lung tissue each showed mRNA expression for Toll-like receptors (TLRs) 1-10. Quantitative RT-PCR analysis showed that Pam3CSK4 (an agonist of TLR1/2) and interleukin (IL)-17A significantly induced TAP gene expression in tracheal epithelial cells after only 4-8 h of stimulation. Flagellin (a TLR5 agonist), lipopolysaccharide and interferon-α also had stimulatory effects, but little or no response was found with class B CpG ODN 2007 (TLR9 agonist) or lipoteichoic acid (TLR2 agonist). The use of combined agonists had little or no enhancing effect above that of single agonists. Thus, Pam3CSK4, IL-17A and lipopolysaccharide rapidly and significantly induce TAP gene expression, suggesting that these stimulatory pathways may be of value for enhancing innate immunity in feedlot cattle at times of susceptibility to disease.
authors.affiliation: Department of Pathobiology, University of Guelph, Guelph, ON, N1G 2 W1, Canada. lesleymb@mun.ca.
authors.forename: Lesley
authors.initials: L
authors.lastname: Berghuis
authors.affiliation: Department of Pathobiology, University of Guelph, Guelph, ON, N1G 2 W1, Canada. abdelazk@uoguelph.ca.|Pathology Department, Faculty of Veterinary Medicine, Beni-Suef University, Beni-Suef, Egypt. abdelazk@uoguelph.ca.
authors.forename: Khaled Taha
authors.initials: KT
authors.lastname: Abdelaziz
authors.affiliation: Department of Pathobiology, University of Guelph, Guelph, ON, N1G 2 W1, Canada. jbierwor@uoguelph.ca.
authors.forename: Jodi
authors.initials: J
authors.lastname: Bierworth
authors.affiliation: Department of Pathobiology, University of Guelph, Guelph, ON, N1G 2 W1, Canada. lwyer@uoguelph.ca.
authors.forename: Leanna
authors.initials: L
authors.lastname: Wyer
authors.affiliation: Department of Pathobiology, University of Guelph, Guelph, ON, N1G 2 W1, Canada. jacobg@uoguelph.ca.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Jacob
authors.affiliation: Department of Animal and Poultry Science, University of Guelph, Guelph, ON, N1G 2 W1, Canada. nkarrow@uoguelph.ca.
authors.forename: Niel A
authors.initials: NA
authors.lastname: Karrow
authors.affiliation: Department of Pathobiology, University of Guelph, Guelph, ON, N1G 2 W1, Canada. shayan@uoguelph.ca.
authors.forename: Shayan
authors.initials: S
authors.lastname: Sharif
authors.affiliation: Department of Pathobiology, University of Guelph, Guelph, ON, N1G 2 W1, Canada. meclark@uoguelph.ca.
authors.forename: Mary Ellen
authors.initials: ME
authors.lastname: Clark
authors.affiliation: Department of Pathobiology, University of Guelph, Guelph, ON, N1G 2 W1, Canada. jcaswell@uoguelph.ca.
authors.forename: Jeff L
authors.initials: JL
authors.lastname: Caswell
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000378:metabolism / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000235:genetics*; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology*; D004847:Epithelial Cells / Q000187:drug effects* / Q000276:immunology* / Q000382:microbiology; D005786:Gene Expression Regulation / Q000187:drug effects*; D018928:Immunity, Mucosal / Q000187:drug effects; D008024:Ligands; D008070:Lipopolysaccharides / Q000494:pharmacology; D051193:Toll-Like Receptors / Q000819:agonists / Q000235:genetics* / Q000378:metabolism; D014132:Trachea / Q000187:drug effects / Q000276:immunology / Q000382:microbiology
chemical_list: D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D008024:Ligands; D008070:Lipopolysaccharides; D051193:Toll-Like Receptors