title: The molecule of DC-SIGN captures enterovirus 71 and confers dendritic cell-mediated viral trans-infection.
abstract: BACKGROUND
  Enterovirus 71 (EV71) is the main causative agent of hand, foot and mouth disease that occurs in young children. Neither antiviral agents nor vaccines are available for efficiently combating viral infection. Study of EV71-host interplay is important for understanding viral infection and developing strategies for prevention and therapy. Here the interactions of EV71 with human dendritic cells were analyzed.
  
  
  METHODS
  EV71 capture, endocytosis, infection, and degradation in monocyte-derived dendritic cells (MDDCs) were detected by Flow cytometry or real-time (RT-) PCR, and MDDCs-mediated EV71 trans-infection of RD cells was determined via coculture system. Cell morphology or viability was monitored with microscopy or flow cytometry. SiRNA interference was used to knock down gene expression.
  
  
  RESULTS
  MDDCs can bind EV71, but these loaded-EV71 particles in MDDCs underwent a rapid degradation in the absence of efficient replication; once the captured EV71 encountered susceptible cells, MDDCs efficiently transferred surface-bound viruses to target cells. The molecule of DC-SIGN (DC-specific intercellular adhesion molecule-3 grabbing nonintegrin) mediated viral binding and transfer, because interference of DC-SIGN expression with specific siRNAs reduced EV71 binding and impaired MDDC-mediated viral trans-infection, and exogenous expression of DC-SIGN molecule on Raji cell initiated viral binding and subsequent transmission.
  
  
  CONCLUSIONS
  MDDCs could bind efficiently EV71 viruses through viral binding to DC-SIGN molecule, and these captured-viruses could be transferred to susceptible cells for robust infection. The novel finding of DC-mediated EV71 dissemination might facilitate elucidation of EV71 primary infection and benefit searching for new clues for preventing viruses from initial infection.
authors.forename: Xiao-Xin
authors.initials: XX
authors.lastname: Ren
authors.forename: Li
authors.initials: L
authors.lastname: Ma
authors.forename: Qing-Wei
authors.initials: QW
authors.lastname: Liu
authors.forename: Chuan
authors.initials: C
authors.lastname: Li
authors.forename: Zhong
authors.initials: Z
authors.lastname: Huang
authors.forename: Li
authors.initials: L
authors.lastname: Wu
authors.forename: Si-Dong
authors.initials: SD
authors.lastname: Xiong
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Wang
authors.affiliation: Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China. hbwang@sibs.ac.cn.
authors.forename: Hai-Bo
authors.initials: HB
authors.lastname: Wang
mesh_terms: D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D018920:Coculture Techniques; D003713:Dendritic Cells / Q000821:virology*; D029821:Enterovirus A, Human / Q000276:immunology* / Q000502:physiology*; D054884:Host-Pathogen Interactions; D006801:Humans; D037181:Lectins, C-Type / Q000235:genetics / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D053585:Virus Attachment; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin
chemical_list: D015815:Cell Adhesion Molecules; D037181:Lectins, C-Type; D011956:Receptors, Cell Surface; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin