title: A comparison of pro-inflammatory cytokine mRNA expression in equine bronchoalveolar lavage (BAL) and peripheral blood.
abstract: An imbalance in various cytokine mRNA expression in bronchoalveolar lavage (BAL) and peripheral blood mononuclear cells (PBMC) in horses suffering from recurrent airway obstruction (RAO) has been demonstrated; however, the natural variation of cytokine expression in healthy horses has yet to be described. The objectives of this study were to: (1) identify age-related differences in the expression of pro-inflammatory cytokines in BAL and PBMC, (2) compare the expression of pro-inflammatory cytokines between BAL and PBMC, and (3) evaluate the relationship between BAL pro-inflammatory cytokine expression and BAL cytology. Cells from BAL and PBMC were collected from 66 horses and stimulated with LPS and PGN. The expression of IL-1β, IL-6, IL-8, TNF-α and TLR-4 were measured using qPCR. A significant age-related decrease for IL-1β and IL-8 in BAL, significant difference in cytokine mRNA expressions between BAL and PBMC and a significant relationship between TLR-4 and IL-8 in LPS stimulated BAL samples and the percentage of neutrophils in BAL cytology were found. In conclusion, the natural age-related decrease in pro-inflammatory cytokine expression in BAL is new knowledge; this in contrast to other age-related findings associated with PBMC, where pro-inflammatory cytokines are known to increase with age in both horses and humans, the phenomenon known as 'inflamm-aging'.
authors.affiliation: Department of Large Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2630 Taastrup, Denmark. Electronic address: sannih@sund.ku.dk.
authors.forename: S
authors.initials: S
authors.lastname: Hansen
authors.affiliation: Department of Large Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2630 Taastrup, Denmark.
authors.forename: K E
authors.initials: KE
authors.lastname: Baptiste
authors.affiliation: Department of Large Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2630 Taastrup, Denmark.
authors.forename: J
authors.initials: J
authors.lastname: Fjeldborg
authors.affiliation: Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY 40546-0099, United States.
authors.forename: A
authors.initials: A
authors.lastname: Betancourt
authors.affiliation: Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY 40546-0099, United States.
authors.forename: D W
authors.initials: DW
authors.lastname: Horohov
mesh_terms: D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology / Q000276:immunology; D016207:Cytokines / Q000235:genetics*; D015870:Gene Expression; D006736:Horses / Q000235:genetics* / Q000276:immunology*; D018836:Inflammation Mediators / Q000378:metabolism; D053583:Interleukin-1beta / Q000235:genetics; D015850:Interleukin-6 / Q000235:genetics; D016209:Interleukin-8 / Q000235:genetics; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008070:Lipopolysaccharides / Q000276:immunology; D010457:Peptidoglycan / Q000276:immunology; D012333:RNA, Messenger / Q000235:genetics*; D051197:Toll-Like Receptor 4 / Q000235:genetics; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators; D053583:Interleukin-1beta; D015850:Interleukin-6; D016209:Interleukin-8; D008070:Lipopolysaccharides; D010457:Peptidoglycan; D012333:RNA, Messenger; D051197:Toll-Like Receptor 4; D014409:Tumor Necrosis Factor-alpha
keywords: Aging; BAL; Equine; Polymerase chain reaction; Pro-inflammatory cytokines