title: Stimulatory effects of human cytomegalovirus tegument protein pp71 lead to increased expression of CCL2 (monocyte chemotactic protein-1) during infection.
abstract: Human cytomegalovirus (CMV) is the most common infectious cause of congenital birth defects in developed countries. Studies of infected amniotic fluid and placentae show CMV infection leads to a pro-inflammatory shift in cytokine profiles with implications for pathogenesis of foetal disease. ELISA, immunofluorescence and real-time-PCR assays were used to investigate CCL2 (monocyte chemotactic protein-1) and TNF-α changes following CMV infection of human fibroblasts, as well as following transient expression of CMV gene products in HeLa cells. Infection of human fibroblasts with CMV AD169 resulted in increased cytoplasmic and extracellular expression of CCL2 during early stages of infection, followed by marked downregulation of the chemokine at late times. Induction of CCL2 was not observed with CMV clinical strain Merlin, consistent with the postulated immune-evasion potential of this genetically intact WT strain. Comparison between live and UV-irradiated virus infections showed that changes in CCL2 levels were a direct response to active CMV replication. There were no significant changes in TNF-α expression during a parallel time-course of CMV infection. In transient transfection assays, overexpression of CMV tegument protein pp71 resulted in intracellular and extracellular upregulation of CCL2 protein. mRNA analysis showed that pp71-induced elevation in CCL2 was mediated through transcriptional upregulation. The data showed that CMV-induced upregulation of CCL2 during early stages of infection was mediated, at least in part, by stimulation of viral pp71, which may contribute to viral pathogenesis through enhanced virus dissemination.
authors.affiliation: 1Virology Research Laboratory, Department of Microbiology, South Eastern Area Laboratory Services, Prince of Wales Hospital, Sydney, NSW, Australia 2School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia 3Australian Centre for Perinatal Science, University of New South Wales, Sydney, NSW, Australia.
authors.forename: Zin
authors.initials: Z
authors.lastname: Naing
authors.affiliation: 4Institut für Klinische und Molekulare Virologie, Universität Erlangen-Nürnberg, Erlangen, Germany.
authors.forename: Rike
authors.initials: R
authors.lastname: Webel
authors.affiliation: 1Virology Research Laboratory, Department of Microbiology, South Eastern Area Laboratory Services, Prince of Wales Hospital, Sydney, NSW, Australia 5School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia.
authors.forename: Stuart
authors.initials: S
authors.lastname: Hamilton
authors.affiliation: 4Institut für Klinische und Molekulare Virologie, Universität Erlangen-Nürnberg, Erlangen, Germany.
authors.forename: Cathrin
authors.initials: C
authors.lastname: Schmeiser
authors.affiliation: 1Virology Research Laboratory, Department of Microbiology, South Eastern Area Laboratory Services, Prince of Wales Hospital, Sydney, NSW, Australia 5School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia.
authors.forename: Gillian
authors.initials: G
authors.lastname: Scott
authors.affiliation: 4Institut für Klinische und Molekulare Virologie, Universität Erlangen-Nürnberg, Erlangen, Germany.
authors.forename: Manfred
authors.initials: M
authors.lastname: Marschall
authors.affiliation: 3Australian Centre for Perinatal Science, University of New South Wales, Sydney, NSW, Australia 2School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia 1Virology Research Laboratory, Department of Microbiology, South Eastern Area Laboratory Services, Prince of Wales Hospital, Sydney, NSW, Australia.
authors.forename: William
authors.initials: W
authors.lastname: Rawlinson
mesh_terms: D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000096:biosynthesis*; D003587:Cytomegalovirus / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000276:immunology / Q000821:virology; D005347:Fibroblasts / Q000276:immunology / Q000821:virology; D005455:Fluorescent Antibody Technique; D020869:Gene Expression Profiling; D006801:Humans; D060888:Real-Time Polymerase Chain Reaction; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D014764:Viral Proteins / Q000276:immunology*
chemical_list: D018932:Chemokine CCL2; D014409:Tumor Necrosis Factor-alpha; D014764:Viral Proteins; C051298:cytomegalovirus phosphoprotein 71kDa