title: Dengue virus-induced autophagosomes and changes in endomembrane ultrastructure imaged by electron tomography and whole-mount grid-cell culture techniques.
abstract: The biogenesis events and formation of dengue virus (DENV) in the infected host cells remain incompletely understood. In the present study, we examined the ultrastructural changes associated with DENV-2 replication in three susceptible host cells, C6/36, Vero and SK Hep1, a cell line of human endothelial origin, using transmission electron microscopy, whole-mount grid-cell culture techniques and electron tomography (ET). The prominent feature in C6/36 cells was the formation of large perinuclear vacuoles with mature DENV particles, and on-grid whole-mount examination of the infected Vero cells showed different forms of DENV core structures associated with cellular membranes within 48 h after infection. Distinct multivesicular structures and prominent autophagic vesicles were seen in the infected SK Hep1 cells when compared with the other two cell lines. ET showed the three-dimensional organization of these vesicles as a continuous system. This is the first report of ET-based analysis of DENV-2 replication in a human endothelial cell line. These results further emphasizes the strong role played by intracellular host membranes-virus interactions in the biogenesis of DENV and strongly argues for the possibility of targeting compounds to block such structure formation as key anti-dengue agents.
authors: Electron Microscopy Group, National Institute of Virology (ICMR), 20A Dr Ambedkar Road, Pune 411001, India.
authors: Shobha
authors: S
authors: Gangodkar
authors: Preksha
authors: P
authors: Jain
authors: Nishikant
authors: N
authors: Dixit
authors: Kanjaksha
authors: K
authors: Ghosh
authors: Atanu
authors: A
authors: Basu
mesh_terms: D000818:Animals; D018929:Cell Culture Techniques / Q000295:instrumentation / Q000379:methods; D002460:Cell Line; D002462:Cell Membrane / Q000648:ultrastructure* / Q000821:virology; D002522:Chlorocebus aethiops; D003716:Dengue Virus / Q000472:pathogenicity*; D055032:Electron Microscope Tomography / Q000379:methods; D042783:Endothelial Cells / Q000648:ultrastructure* / Q000821:virology; D006801:Humans; D046529:Microscopy, Electron, Transmission / Q000379:methods; D010588:Phagosomes / Q000648:ultrastructure*; D014709:Vero Cells; D014779:Virus Replication