Genomes and Genes
Human cytomegalovirus entry into epithelial and endothelial cells
Principal Investigator: David C Johnson
Abstract: Human cytomegalovirus (HCMV) is a ubiquitous, normally benign virus that establishes lifelong persistence and/or latency. However, infections in immunodeficient or immunosuppressed patients often cause severe disease including pneumonia, gastrointestinal syndromes, hepatitis, retinitis, and encephalitis. Importantly, HCMV frequently contributes to the rejection of transplanted organs. In immunologically naive children, HCMV can cause developmental defects of the CNS, especially deafness. Moreover, clinically recognized cases of HCMV in young children may represent only the "tip of the iceberg", many other infants with less well pronounced HCMV in utero may suffer more subtle developmental defects. HCMV causes a diverse spectrum of diseases, in part, related to a capacity to infect a broad array of cell types including epithelial, endothelial and glial cells, fibroblasts, monocyte-macrophages (M/M) and neurons. In order to infect all these different cell types, HCMV must bind onto cell surfaces and enter the cells. This fundamentally important first step in HCMV replication play an important role in virus tropism and pathogenesis, yet is poorly understood. In part, gaps in understanding HCMV entry, relate to the fact that extensively studied laboratory strains of HCMV fail to enter M/M, epithelial and endothelial cells. Clinical strains of HCMV enter all these diverse cell types, apparently because these viruses express two entry glycoproteins: gH/gL/UL128-131, required for entry into epithelial and endothelial cells and gH/gL/gO, required for entry into fibroblasts. Lab strains of HCMV (propagated long term on fibroblasts) express only gH/gL/gO. When we transduced epithelial cells to cause expression of gH/gL/UL128-131, HCMV entry into the cells was blocked. This "interference" with virus entry provides principal support for our hypothesis that gH/gL/UL128-131 functions to bind epithelial cell receptors. We are testing the related hypothesis that gH/gL/gO acts to bind fibroblast receptors. We also found that expression of gH/gL (without UL128-131) and a second HCMV glycoprotein, gB, caused fusion of epithelial cells, surprisingly, even when expressed in trans, i.e. gB in one set of cells and gH/gL in other cells. These observations have important conceptual implications for models of how viral proteins fuse membranes. Our ongoing research is focused on understanding how the two HCMV glycoproteins gH/gL/UL128-131 and gH/gL/gO are assembled and incorporated into virus particles, and how these proteins function in virus entry. Moreover, we will study the molecular mechanisms of gB and gH/gL-mediated membrane fusion. Other efforts will focus on the identification of novel cellular receptors that will explain clinical HCMV entry into epithelial and endothelial cells. Information about viral and cellular entry mediators is key to a better understanding of HCMV pathogenesis and for the design of vaccines and anti-virals. PUBLIC HEALTH RELEVANCE: Human cytomegalovirus (HCMV) causes substantial disease in several vulnerable populations: developing children, transplant patients, and AIDS patients. HCMV can infect a very broad spectrum of human cell types including retinal and gut epithelial cells, endothelial cells, hepatocytes, monocyte-macrophages and glial cells. Our studies will provide a better picture of how HCMV gains entry into biologically relevant epithelial and endothelial cells to facilitate the design of better anti-HCMV drugs and vaccines.
Funding Period: 2009-09-07 - 2014-08-31
more information: NIH RePORT
- A human cytomegalovirus gO-null mutant fails to incorporate gH/gL into the virion envelope and is unable to enter fibroblasts and epithelial and endothelial cellsPaul T Wille
Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon 97239, USA
J Virol 84:2585-96. 2010....
- Human cytomegalovirus TR strain glycoprotein O acts as a chaperone promoting gH/gL incorporation into virions but is not present in virionsBrent J Ryckman
Department of Molecular Microbiology and Immunology, Oregon Health and Sciences University, Portland, Oregon 97239, USA
J Virol 84:2597-609. 2010..Thus, our revised model suggests that both gH/gL and gH/gL/UL128-131 are required for entry into epithelial and endothelial cells...
- Herpesviruses remodel host membranes for virus egressDavid C Johnson
Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon 97219, USA
Nat Rev Microbiol 9:382-94. 2011..In this Review, we describe the remodelling of host membranes that facilitates herpesvirus egress...
- Human cytomegalovirus glycoprotein gO complexes with gH/gL, promoting interference with viral entry into human fibroblasts but not entry into epithelial cellsAdam L Vanarsdall
L 220, Department of Microbiology and Immunology, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
J Virol 85:11638-45. 2011..Together, the results provide additional support for our hypotheses that epithelial cells express putative gH/gL/UL128-1331 receptors important for HCMV entry and that fibroblasts express distinct gH/gL receptors...
- PDGF receptor-α does not promote HCMV entry into epithelial and endothelial cells but increased quantities stimulate entry by an abnormal pathwayAdam L Vanarsdall
Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon, USA
PLoS Pathog 8:e1002905. 2012..Given that PDGFRα increased infection of some cells to 90%, PDGFRα may be very useful in overcoming inefficient HCMV entry (even of lab strains) into the many difficult-to-infect cell types...
- HCMV gB shares structural and functional properties with gB proteins from other herpesvirusesSapna Sharma
Department of Molecular Biology and Microbiology, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
Virology 435:239-49. 2013..Our work establishes structural and functional similarities between gB proteins from three subfamilies of herpesviruses...
- Human cytomegalovirus (HCMV) glycoprotein gB promotes virus entry in trans acting as the viral fusion protein rather than as a receptor-binding proteinPaul T Wille
Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR, USA
MBio 4:e00332-13. 2013..In contrast, virus particles lacking gH/gL could not enter cells expressing gH/gL. Our study supports the hypothesis that gB is the fusion protein and gH/gL acts upstream of gB to bind receptors and then activate gB for fusion...
- Placental trophoblast infection and TLR mediated response to congenital CMVAlistair McGregor; Fiscal Year: 2013..These studies will employ conventional histopathological and immunohistochemical approaches as well as novel techniques including the use of bioluminescence imaging of viral dissemination in the animal model. ..
- Assay development to discover therapeutics against human cytomegalovirusDomenico Tortorella; Fiscal Year: 2013..These compounds in combination with current therapy as a multi-drug cocktail would likely be very effective at treating patients with a high HCMV viral load and limit HCMV associated diseases. ..
- Immunobioogy for Marrow Allografts for LeukemiaRICHARD JOHN O'REILLY; Fiscal Year: 2013..The 3 cores include: Core A which provides all patient samples and evaluate grafts pre and post HSCT, Core B Biostatistics and Core C administrative support and oversight. ..
- MCMV Infection of the Developing CNS: Neuroinvasion and Immune ControlWILLIAM JARVIS BRITT; Fiscal Year: 2013....
- Fetal HCMV Infection: Role of the Human PlacentaLENORE PALMA PEREIRA; Fiscal Year: 2013..These could have clinical application in conjunction with biotherapeutic antibodies that suppress HCMV replication, prevent placental dysfunction and improve chances for a healthy baby. ..
- Pacific NorthWest Regional Center of Excellence (PNWRCE)Jay A Nelson; Fiscal Year: 2013..pseudomallei host pathogen response during both the septicemic as well as the intracellular phases of the disease. ..
- Pacific Southwest RCE for Biodefense &Emerging Infectious Diseases ResearchAlan G Barbour; Fiscal Year: 2013..abstract_text> ..
- Optimizing HIV immunogen-BCR interactions for vaccine developmentLEONIDAS A STAMATATOS; Fiscal Year: 2013....
- Rocky Mountain Regional Center of Excellence or Biodefense and Emerging InfectiouJohn T Belisle; Fiscal Year: 2013..abstract_text> ..
- Development of an effective DISC vaccine strategy against congenital CMVAlistair McGregor; Fiscal Year: 2013..The ability of second generation DISC vaccines to protect against congenital GPCMV will be investigated and efficacy determined by comparing it with a recombinant gB vaccine strategy previously investigated in this model. ..
- Northeast Biodefense CenterW Ian Lipkin; Fiscal Year: 2013..As a Center based in a School of Public Health and a State Department of Health, the NBC has a firm commitment to and practical understanding of Emergency Preparedness. ..
- Identification of novel inhibitors targeting entry of human cytomegalovirusDomenico Tortorella; Fiscal Year: 2013....
- New England Regional Center of Excellence in Biodefense and Emerging Infectious DDennis L Kasper; Fiscal Year: 2013..NERCE will also continue its Developmental Projects program and Career Development in Biodefense program in an effort to initiate new research efforts and to attract new investigators to this field. ..
- Evaluation of Protective CMV Vaccines in Rhesus MacaquesDon J Diamond; Fiscal Year: 2013..These studies should lead to an optimal prophylactic HCMV clinical strategy that can lead to clinically relevant reductions in the potential for both vertical and horizontal transmission of HCMV. ..
- CMV Entry-Specific Neutralizing Antibody in Primary Infection in TransplantationMargaret L Green; Fiscal Year: 2013....
- Mechanisms mediating HCMV genome maintenance during latencyLaura Hertel; Fiscal Year: 2013..This work will provide significant insights into a crucial aspect of CMV latency, and will constitute the foundation for the development of innovative therapies with the potential to eradicate this virus from the human population. ..
- Expanding Excellence in Developmental Biology in OklahomaLinda F Thompson; Fiscal Year: 2013..abstract_text> ..
- Protein homeostasis mechanisms underlying enterovirus replication and evolutionRaul Andino; Fiscal Year: 2013..Core A: Administrative Core;and Core B: "High-throughput functional genomics and proteomics core. ..
- Primary Immune Deficiency Treatment ConsortiumMorton Cowan; Fiscal Year: 2013..These studies will resolve critical questions concerning HCT for these disorders and form the basis for future prospective clinical trials. ..
- Preclinical development of human CMV vaccinesMichael A McVoy; Fiscal Year: 2013..Such candidates are anticipated to have improved efficacy over existing candidate vaccines and will be suitable for subsequent clinical development. ..
- Serotonin as a Regulator of Bone Mass Accrual: Basic and ClinicalGerard Karsenty; Fiscal Year: 2013..Together our studies should provide important and novel insights in the genetic and molecular control of bone remodeling as well as in the pathogenesis and treatment of osteoporosis, a major disease of aging. ..
- Vaccine against CMV endothelial tropism &congenital infectionAlistair McGregor; Fiscal Year: 2013....