title: Cytokine gene expression by peripheral blood leukocytes in dogs experimentally infected with a new virulent strain of Ehrlichia canis.
abstract: Ehrlichia canis (E. canis) is a lipopolysaccharide (LPS)-deficient obligatory intracellular bacterium that causes canine monocytic ehrlichiosis, a chronic febrile disease accompanied with hematological abnormality. This study analyzed temporal expression levels of IL-1beta, IL-2, IL-6, IL-8, IFN-gamma, and TNF-alpha mRNA by peripheral blood leukocytes from dogs experimentally infected with a new virulent strain of E. canis by using real-time RT-PCR. Relative levels of IL-1beta and IL-8 transcripts normalized by the beta-actin transcript levels, were significantly upregulated, whereas those of TNF-alpha and IFN-gamma transcripts were only weakly upregulated in all three infected dogs, starting from 2 days up to 52 days post inoculation. The expressions of IL-2 and IL-6 genes were extremely low compared with the positive control (ConA-stimulated canine peripheral blood leukocytes). This study showed that E. canis can induce chronic expression of a subset of proinflammatory cytokine genes: balance, timing, and duration of these cytokine generations may contribute to the progression of canine ehrlichiosis.
authors.affiliation: Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, 1925 Coffey Road, Columbus, Ohio 43210, USA.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Unver
authors.forename: Haibin
authors.initials: H
authors.lastname: Huang
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Rikihisa
mesh_terms: D000818:Animals; D016207:Cytokines / Q000235:genetics*; D004283:Dog Diseases / Q000097:blood / Q000235:genetics* / Q000382:microbiology; D004285:Dogs; D041061:Ehrlichia canis / Q000472:pathogenicity; D016873:Ehrlichiosis / Q000097:blood / Q000235:genetics / Q000662:veterinary*; D005260:Female; D007962:Leukocytes / Q000502:physiology; D010976:Platelet Count; D012329:RNA, Bacterial / Q000235:genetics / Q000302:isolation & purification; D012333:RNA, Messenger / Q000235:genetics / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014774:Virulence
chemical_list: D016207:Cytokines; D012329:RNA, Bacterial; D012333:RNA, Messenger