title: Effects of stress, mimicked by administration of corticosterone in drinking water, on the expression of chicken cytokine and chemokine genes in lymphocytes.
abstract: In this study, we identify molecular mediators that participate in the regulation of the immune response during corticosterone-induced stress in chickens. At 7 weeks of age, 120 chickens were exposed for 1 week to corticosterone treatment. Cytokine and chemokine mRNA expression levels were evaluated in peripheral blood and splenic lymphocytes. Expression levels of interleukin (IL)-1beta, IL-6, IL-18 and transforming growth factor (TGF)-beta4 mRNA were significantly up-regulated in lymphocytes 3 h after first treatment with corticosterone. TGF-beta4 and IL-18 remained elevated 1 week post-initial treatment. Compared with controls, corticosterone-treated birds showed greater expression levels of chemokine (CC) mRNA, particularly for CCLi2, CCL5 (RANTES), CCL16 and CXCLi1, in peripheral and splenic lymphocytes 3 h post-initial exposure. CCLi2 mRNA was highly expressed in splenocytes at all time-points. Administration of corticosterone significantly increased circulating corticosterone concentrations and decreased total lymphocyte counts at 3, 24 h and 1 week post-initiation of corticosterone treatment. There was a positive correlation between plasma corticosterone concentrations and CCL5 and CCL16 mRNA at 3 h post-initial administration. At 1 week post-initial treatment, corticosterone concentrations correlated positively with CCL5 and negatively with IL-18 mRNA level. Conditions associated with significant changes in corticosterone levels might therefore affect the immune response by increasing pro-inflammatory responses, leading to potential modulation of the Th1/Th2 balance.
authors.affiliation: School of Animal Studies, University of Queensland, Gatton, Australia. s.shini@uq.edu.au
authors.forename: S
authors.initials: S
authors.lastname: Shini
authors.forename: P
authors.initials: P
authors.lastname: Kaiser
mesh_terms: D000818:Animals; D018925:Chemokines / Q000378:metabolism*; D002645:Chickens; D003345:Corticosterone / Q000494:pharmacology*; D016207:Cytokines / Q000378:metabolism*; D005260:Female; D007249:Inflammation / Q000276:immunology; D020382:Interleukin-18 / Q000378:metabolism; D008214:Lymphocytes / Q000276:immunology* / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D013312:Stress, Physiological / Q000502:physiology*; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology
chemical_list: D018925:Chemokines; D016207:Cytokines; D020382:Interleukin-18; D012333:RNA, Messenger; D003345:Corticosterone