title: Activation of PI 3-kinase/Akt/NF-kappaB and Stat3 signaling by avian reovirus S1133 in the early stages of infection results in an inflammatory response and delayed apoptosis.
abstract: Avian reovirus (ARV) strain S1133 causes apoptosis in host cells in the middle to late stages of infection. This study investigated the early-stage biological response and intracellular signaling in ARV S1133-infected Vero and chicken cells. Treatment with conditioned medium from ARV S1133-infected cells increased the chemotactic activity of U937 cells. Neutralizing antibodies against IL-1beta and IL-6 showed that both cytokines contribute to viral-induced inflammation but neither affect cell survival. Inhibition of Akt, NF-kappaB, and Stat3 released the chemotactic activity and anti-apoptotic effect elicited by ARV S1133. ARV S1133 activated PI 3-kinase-dependent Akt/NF-kappaB and p70 S6 kinase, as well as Stat3; however, p70 S6 kinase was not involved in ARV S1133-mediated effects. DF1 cells over-expressing constitutively active PI 3-kinase and Stat3 showed association with enhancement of anti-apoptotic activity. In conclusion, in the early stages of ARV S1133 infection, activation of cell survival signals contributes to virus-induced inflammation and anti-apoptotic response.
authors.affiliation: Graduate Institute and Department of Life Science, Tzu-Chi University, Hualien, Taiwan.
authors.forename: Ping-Yuan
authors.initials: PY
authors.lastname: Lin
authors.forename: Hung-Jen
authors.initials: HJ
authors.lastname: Liu
authors.forename: Ming-Huei
authors.initials: MH
authors.lastname: Liao
authors.forename: Ching-Dong
authors.initials: CD
authors.lastname: Chang
authors.forename: Chi-I
authors.initials: CI
authors.lastname: Chang
authors.forename: Hsueh-Ling
authors.initials: HL
authors.lastname: Cheng
authors.forename: Jeng-Woei
authors.initials: JW
authors.lastname: Lee
authors.forename: Wen-Ling
authors.initials: WL
authors.lastname: Shih
mesh_terms: D000818:Animals; D017209:Apoptosis; D002460:Cell Line; D002642:Chick Embryo; D002522:Chlorocebus aethiops; D054884:Host-Pathogen Interactions; D006801:Humans; D007249:Inflammation / Q000209:etiology; D053583:Interleukin-1beta / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D030101:Orthoreovirus, Avian / Q000472:pathogenicity*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D012088:Reoviridae Infections / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D050796:STAT3 Transcription Factor / Q000378:metabolism*; D015398:Signal Transduction; D014709:Vero Cells
chemical_list: D053583:Interleukin-1beta; D015850:Interleukin-6; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D050796:STAT3 Transcription Factor