title: Endothelial cell surface expression of protein disulfide isomerase activates β1 and β3 integrins and facilitates dengue virus infection.
abstract: Infection with dengue virus (DENV) causes diseases ranging from mild dengue fever to severe hemorrhage or shock syndrome. DENV infection of endothelial cells may cause cell apoptosis or vascular leakage and result in clinical illness of hemorrhage. However, the endothelial cell molecules involved in DENV infection and the mechanisms governing virus-cell interactions are still uncertain. Since protein disulfide isomerase (PDI) reducing function at the cell surface was shown to be required for entry of certain viruses and bacteria, we explored the role of PDI expressed on endothelial cell surface in DENV infection. Using siRNA to knock down PDI, DENV infection was reduced which could be reversed by treating cells with a reducing agent Tris(2-carboxyethyl)phosphine hydrochloride (TCEP). DENV-induced PDI surface expression was mediated through the Lys-Asp-Glu-Leu (KDEL) receptor-Src family kinase signal pathway. Furthermore, cell surface PDI colocalized with β1 and β3 integrins after DENV infection, and the activation of integrins was blocked by PDI inhibition. Finally, blockade of PDI inhibited DENV entry into endothelial cells. Our findings suggest a novel mechanism whereby surface PDI which causes integrin activation is involved in DENV entry, and DENV infection further increases PDI surface expression at later time points. These findings may have implications for anti-DENV drug design.
authors.affiliation: Institute of Basic Medical Sciences, National Cheng Kung University Medical College, Tainan, Taiwan.
authors.forename: Shu-Wen
authors.initials: SW
authors.lastname: Wan
authors.forename: Chiou-Feng
authors.initials: CF
authors.lastname: Lin
authors.forename: Yi-Tien
authors.initials: YT
authors.lastname: Lu
authors.forename: Huan-Yao
authors.initials: HY
authors.lastname: Lei
authors.forename: Robert
authors.initials: R
authors.lastname: Anderson
authors.forename: Yee-Shin
authors.initials: YS
authors.lastname: Lin
mesh_terms: D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism / Q000821:virology; D003715:Dengue / Q000209:etiology* / Q000378:metabolism* / Q000821:virology; D003716:Dengue Virus / Q000472:pathogenicity; D004721:Endoplasmic Reticulum / Q000378:metabolism; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism* / Q000821:virology*; D055785:Gene Knockdown Techniques; D006056:Golgi Apparatus / Q000378:metabolism; D006801:Humans; D019012:Integrin beta1 / Q000378:metabolism*; D039661:Integrin beta3 / Q000378:metabolism*; D010720:Phosphines / Q000494:pharmacology; D019704:Protein Disulfide-Isomerases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics; D018000:Receptors, Peptide / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D019163:Reducing Agents / Q000494:pharmacology; D015398:Signal Transduction; D053586:Virus Internalization / Q000187:drug effects
chemical_list: D019012:Integrin beta1; D039661:Integrin beta3; D010720:Phosphines; D019704:Protein Disulfide-Isomerases; D034741:RNA, Small Interfering; D018000:Receptors, Peptide; D019163:Reducing Agents; C064459:KDEL receptor; C080938:tris(2-carboxyethyl)phosphine