title: MEK/ERK signaling pathway is required for enterovirus 71 replication in immature dendritic cells.
abstract: BACKGROUND
  The mitogen-activated protein kinase kinase/extracellular-signal-regulated kinase (MEK/ERK) signaling pathway is involved in viral life cycle. However, the effect of MEK/ERK pathway in enterovirus 71(EV71)-infected immature dendritic cells (iDCs) is still unclear.
  
  
  METHODS
  Human peripheral blood mononuclear cells (PBMCs) were isolated and induced to generate iDCs. Unifected iDCs and EV71-infected iDCs with a multiplicity of infection (MOI = 5) were analyzed by flow cytometry. Differential gene expressions of MEK/ERK signaling pathway molecules in EV71-infected iDCs were performed by PCR arrays. The phosphorylation of MEK/ERK pathway molecules in EV71-infected iDCs preincubated without or with U0126 (20 μM) at indicated times was detected by Western blot. The concentrations of IL-1α, IL-2, IL-6, IL-12, TNF-α, IFN-α1, IFN-β and IFN-γ in culture supernatant were analyzed by the luminex fluorescent technique.
  
  
  RESULTS
  When iDCs were infected with EV71 for 24 h, the percentage of CD80, CD83, CD86 and HLA-DR expressed on iDCs significantly increased. PCR arrays showed that gene expressions of molecules in MEK/ERK signaling pathway were remarkably upregulated in EV71-infected iDCs. EV71 infection activated both MEK1/2 and ERK1/2, which phosphorylated their downstream transcription factor c-Fos, c-Jun, c-myc and Elk1. Importantly, the treatment of U0126 significantly inhibited MEK/ERK signaling pathway molecules and severely impaired virus replication., Additionally, EV71 infection promoted the expression of son of sevenless (SOS1) and increased the secretion of IL-1α, IL-2, IL-6, IL-12, TNF-α,IFN-β and IFN-γ. Furthermore,the release of IL-1α, IL-2,IL-6 and TNF-α could be effectively suppressed by inhibitor U0126.
  
  
  CONCLUSIONS
  Our data suggest that the MEK/ERK signaling pathway plays an important role in EV71-infected iDCs and these molecules may be potential targets for the development of new anti-EV71 drugs.
authors.affiliation: Department of Clinical Laboratory, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, Jiangsu, 213003, PR China. shiweifeng67@163.com.
authors.forename: Weifeng
authors.initials: W
authors.lastname: Shi
authors.affiliation: Department of Clinical Laboratory, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, Jiangsu, 213003, PR China. houxueling6139692@126.com.
authors.forename: Xueling
authors.initials: X
authors.lastname: Hou
authors.affiliation: Department of Clinical Laboratory, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, Jiangsu, 213003, PR China. muyiqing881023@126.com.
authors.forename: Hongjun
authors.initials: H
authors.lastname: Peng
authors.affiliation: Department of Clinical Laboratory, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, Jiangsu, 213003, PR China. 894834663@qq.com.
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Clinical Laboratory, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, Jiangsu, 213003, PR China. lyy841477151@163.com.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Clinical Laboratory, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, Jiangsu, 213003, PR China. 448246916@qq.com.
authors.forename: Zhiwen
authors.initials: Z
authors.lastname: Gu
authors.affiliation: Department of Clinical Laboratory, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, Jiangsu, 213003, PR China. jiangqb68@163.com.
authors.forename: Qingbo
authors.initials: Q
authors.lastname: Jiang
authors.affiliation: Department of Clinical Laboratory, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, Jiangsu, 213003, PR China. shimeim2002@yahoo.com.cn.
authors.forename: Mei
authors.initials: M
authors.lastname: Shi
authors.affiliation: Department of Clinical Laboratory, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, Jiangsu, 213003, PR China. kegebo123@163.com.
authors.forename: Yun
authors.initials: Y
authors.lastname: Ji
authors.affiliation: Department of Tumor Biological Treatment, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, 213003, China. jjtnew@163.com.
authors.forename: Jingting
authors.initials: J
authors.lastname: Jiang
mesh_terms: D015153:Blotting, Western; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism; D003713:Dendritic Cells / Q000821:virology*; D029821:Enterovirus A, Human / Q000502:physiology*; D020869:Gene Expression Profiling; D054884:Host-Pathogen Interactions; D006801:Humans; D008163:Luminescent Measurements; D020935:MAP Kinase Signaling System; D010766:Phosphorylation; D016133:Polymerase Chain Reaction; D011499:Protein Processing, Post-Translational; D014779:Virus Replication
chemical_list: D016207:Cytokines