1
|
He L, Hertel L, James CD, Morgan IM, Klingelhutz AJ, Fu TM, Kauvar LM, McVoy MA. Inhibition of human cytomegalovirus entry into mucosal epithelial cells. Antiviral Res 2024; 230:105971. [PMID: 39074588 PMCID: PMC11408113 DOI: 10.1016/j.antiviral.2024.105971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 07/16/2024] [Accepted: 07/24/2024] [Indexed: 07/31/2024]
Abstract
Human cytomegalovirus (CMV) causes serious developmental disabilities in newborns infected in utero following oral acquisition by the mother. Thus, neutralizing antibodies in maternal saliva have potential to prevent maternal infection and, consequently, fetal transmission and disease. Based on standard cell culture models, CMV entry mediators (and hence neutralizing targets) are cell type-dependent: entry into fibroblasts requires glycoprotein B (gB) and a trimeric complex (TC) of glycoproteins H, L, and O, whereas endothelial and epithelial cell entry additionally requires a pentameric complex (PC) of glycoproteins H and L with UL128, UL130, and UL131A. However, as the mediators of mucosal cell entry and the potential impact of cellular differentiation remained unclear, the present studies utilized mutant viruses, neutralizing antibodies, and soluble TC-receptor to determine the entry mediators required for infection of mucocutaneus cell lines and primary tonsil epithelial cells. Entry into undifferentiated cells was largely PC-dependent, but PC-independent entry could be induced by differentiation. TC-independent entry was also observed and varied by cell line and differentiation. Infection of primary tonsil cells from some donors was entirely TC-independent. In contrast, an antibody to gB or disruption of virion attachment using heparin blocked entry into all cells. These findings indicate that CMV entry into the spectrum of cell types encountered in vivo is likely to be more complex than has been suggested by standard cell culture models and may be influenced by the relative abundance of virion envelope glycoprotein complexes as well as by cell type, tissue of origin, and state of differentiation.
Collapse
Affiliation(s)
- Li He
- Department of Pediatrics, Virginia Commonwealth University, Richmond, VA, 23298, USA
| | - Laura Hertel
- Department of Pediatrics, School of Medicine, University of California San Francisco, Oakland, CA, 94609, USA
| | - Claire D James
- Philips Institute for Oral Health Research, Virginia Commonwealth University, Richmond, VA, 23284, USA
| | - Iain M Morgan
- Philips Institute for Oral Health Research, Virginia Commonwealth University, Richmond, VA, 23284, USA
| | - Aloysius J Klingelhutz
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA, 52242, USA
| | - Tong-Ming Fu
- Texas Therapeutics Institute, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | | | - Michael A McVoy
- Department of Pediatrics, Virginia Commonwealth University, Richmond, VA, 23298, USA.
| |
Collapse
|
2
|
Ohman MS, Albright ER, Gelbmann CB, Kalejta RF. The Pentamer glycoprotein complex inhibits viral Immediate Early transcription during Human Cytomegalovirus infections. Proc Natl Acad Sci U S A 2024; 121:e2408078121. [PMID: 39292744 PMCID: PMC11441559 DOI: 10.1073/pnas.2408078121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Accepted: 08/16/2024] [Indexed: 09/20/2024] Open
Abstract
The Pentamer complex of Human Cytomegalovirus (HCMV) consists of the viral glycoproteins gH, gL, UL128, UL130, and UL131 and is incorporated into infectious virions. HCMV strains propagated extensively in vitro in fibroblasts carry UL128, UL130, or UL131 alleles that do not make a functional complex and thus lack Pentamer function. Adding functional Pentamer to such strains decreases virus growth in fibroblasts. Here, we show that the Pentamer inhibits productive HCMV replication in fibroblasts by repressing viral Immediate Early (IE) transcription. We show that ectopic expression of the viral IE1 protein, a target of Pentamer-mediated transcriptional repression, complements the growth defect of a Pentamer-positive virus. Furthermore, we show that the Pentamer also represses viral IE transcription in cell types where HCMV in vitro latency is studied. Finally, we identify UL130 as a functional subunit of the Pentamer for IE transcriptional repression and demonstrate that cyclic AMP Response Element (CRE) and NFkB sites within the Major Immediate Early Promoter that drives IE1 transcription contribute to this repression. We conclude that the HCMV Pentamer represses viral IE transcription.
Collapse
Affiliation(s)
- Michael S Ohman
- Institute for Molecular Virology and McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI 53706
| | - Emily R Albright
- Institute for Molecular Virology and McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI 53706
| | - Christopher B Gelbmann
- Institute for Molecular Virology and McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI 53706
| | - Robert F Kalejta
- Institute for Molecular Virology and McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI 53706
| |
Collapse
|
3
|
Mollik M, Rohorzka A, Chen X, Kropff B, Eisler L, Külekci B, Puchhammer-Stöckl E, Thomas M, Görzer I. Growth defect of domain III glycoprotein B mutants of human cytomegalovirus reverted by compensatory mutations co-localizing in post-fusion conformation. mBio 2024:e0181224. [PMID: 39315800 DOI: 10.1128/mbio.01812-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Accepted: 08/29/2024] [Indexed: 09/25/2024] Open
Abstract
Cell entry is a crucial step for a virus to infect a host cell. Human cytomegalovirus utilizes glycoprotein B (gB) to fuse the viral and host cell membranes upon receptor binding of gH/gL-containing complexes. Fusion is mediated by major conformational changes of gB from a metastable pre-fusion to a stable post-fusion state whereby the central trimeric coiled-coils, formed by domain (Dom)III α helices, remain structurally nearly unchanged. To better understand the role of the stable core, we individually introduced three potentially helix-breaking or one disulfide bond-breaking mutation in the DIII α3 to study different aspects of the viral behavior upon long-term culturing. Two of the three helix-breaking mutations, gB_Y494P and gB_I495P, were lethal for the virus in either fibroblasts or epithelial cells. The third substitution, gB_G493P, on the other hand, displayed a delayed replication and spread, which was more pronounced in epithelial cells, hinting at an impaired fusion. Interestingly, the disulfide bond-breaker mutation, gB_C507S, performed strikingly differently in the two cell types - lethal in epithelial cells and an atypical phenotype in fibroblasts, respectively. Replication curve analyses paired with the infection efficiency, the spread morphology, and the cell-cell fusogenicity suggest a dysregulated fusion process, which could be reverted by second-site mutations mapping predominantly to gB DomV. Our findings underline the functional importance of a stable DomIII core for a well-regulated DomV rearrangement during fusion.IMPORTANCEHuman cytomegalovirus (HCMV) can establish a lifelong infection. In most people, the infection follows an asymptomatic course; however, it is a major cause of morbidity and mortality in immunocompromised patients or neonates. HCMV has a very broad cell tropism, ranging from fibroblasts to epi- and endothelial cells. The virus uses different entry pathways utilizing the core fusion machinery consisting of glycoprotein complexes gH/gL and glycoprotein B (gB). The fusion protein gB undergoes fundamental rearrangements from a metastable pre-fusion to a stable post-fusion conformation. Here, we characterized the viral behavior after the introduction of four single-point mutations in the gB central core. These led to various cell type-specific atypical phenotypes and the emergence of compensatory mutations, demonstrating an important interaction between domains III and V. We provide a new basis for the development of a structurally and functionally altered gB, which can further serve as a tool for drug and vaccine development.
Collapse
Affiliation(s)
- Madlen Mollik
- Center for Virology, Medical University of Vienna, Vienna, Austria
| | - Andreas Rohorzka
- Center for Virology, Medical University of Vienna, Vienna, Austria
| | - Xiaohan Chen
- Virologisches Institut, Klinische und Molekulare Virologie, Friedrich Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Barbara Kropff
- Virologisches Institut, Klinische und Molekulare Virologie, Friedrich Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Lukas Eisler
- Center for Virology, Medical University of Vienna, Vienna, Austria
| | - Büsra Külekci
- Center for Virology, Medical University of Vienna, Vienna, Austria
| | | | - Marco Thomas
- Virologisches Institut, Klinische und Molekulare Virologie, Friedrich Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Irene Görzer
- Center for Virology, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
4
|
Obergfäll D, Wild M, Sommerer M, Barillas Dahm M, Kicuntod J, Tillmanns J, Kögler M, Lösing J, Dhotre K, Müller R, Wangen C, Wagner S, Phan QV, Wiebusch L, Briestenská K, Mistríková J, Kerr-Jones L, Stanton RJ, Voigt S, Hahn F, Marschall M. Cyclin-Dependent Kinase 8 Represents a Positive Regulator of Cytomegalovirus Replication and a Novel Host Target for Antiviral Strategies. Pharmaceutics 2024; 16:1238. [PMID: 39339274 PMCID: PMC11435438 DOI: 10.3390/pharmaceutics16091238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2024] [Revised: 09/19/2024] [Accepted: 09/21/2024] [Indexed: 09/30/2024] Open
Abstract
Background. Cyclin-dependent kinase 8 (CDK8) is a multifaceted regulator and represents a catalytic component of the transcriptional Mediator complex. CDK8 activity, on the one hand, increases transcriptional elongation by the recruitment of Mediator/super elongation complexes, but, on the other hand, negatively regulates CDK7-controlled transcriptional initiation through inactivating cyclin H phosphorylation. Recently, these combined properties of CDK8 have also suggested its rate-limiting importance for herpesviral replication. Objectives. In this paper, we focused on human cytomegalovirus (HCMV) and addressed the question of whether the pharmacological inhibition or knock-down of CDK8 may affect viral replication efficiency in cell culture models. Methods. A number of human and animal herpesviruses, as well as non-herpesviruses, were used to analyze the importance of CDK8 for viral replication in cell culture models, and to assess the antiviral efficacy of CDK8 inhibitors. Results. Using clinically relevant CDK8 inhibitors (CCT-251921, MSC-2530818, and BI-1347), HCMV replication was found strongly reduced even at nanomolar drug concentrations. The EC50 values were consistent for three different HCMV strains (i.e., AD169, TB40, and Merlin) analyzed in two human cell types (i.e., primary fibroblasts and astrocytoma cells), and the drugs comprised a low level of cytotoxicity. The findings highlighted the following: (i) the pronounced in vitro SI values of anti-HCMV activity obtained with CDK8 inhibitors; (ii) a confirmation of the anti-HCMV efficacy by CDK8-siRNA knock-down; (iii) a CDK8-dependent reduction in viral immediate early, early, and late protein levels; (iv) a main importance of CDK8 for viral late-stage replication; (v) several mechanistic aspects, which point to a strong impact on viral progeny production and release, but a lack of CDK8 relevance for viral entry or nuclear egress; (vi) a significant anti-HCMV drug synergy for combinations of inhibitors against host CDK8 and the viral kinase vCDK/pUL97 (maribavir); (vii) finally, a broad-spectrum antiviral activity, as seen for the comparison of selected α-, β-, γ-, and non-herpesviruses. Conclusions. In summary, these novel data provide evidence for the importance of CDK8 as a positive regulator of herpesviral replication efficiency, and moreover, suggest its exploitability as an antiviral target for novel strategies of host-directed drug development.
Collapse
Affiliation(s)
- Debora Obergfäll
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| | - Markus Wild
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| | - Mona Sommerer
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| | - Malena Barillas Dahm
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| | - Jintawee Kicuntod
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| | - Julia Tillmanns
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| | - Melanie Kögler
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| | - Josephine Lösing
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| | - Kishore Dhotre
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| | - Regina Müller
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| | - Christina Wangen
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| | - Sabrina Wagner
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| | - Quang V. Phan
- Department of Pediatric Oncology and Hematology, Charité—Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin, Germany; (Q.V.P.); (L.W.)
- Richard Sherwood Laboratory, Brigham and Women’s Hospital, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Lüder Wiebusch
- Department of Pediatric Oncology and Hematology, Charité—Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin, Germany; (Q.V.P.); (L.W.)
| | - Katarína Briestenská
- Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovakia; (K.B.); (J.M.)
- Institute of Virology, Biomedical Research Center, Slovak Academy of Sciences, Dúbravská Cesta 9, 845 05 Bratislava, Slovakia
| | - Jela Mistríková
- Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovakia; (K.B.); (J.M.)
- Institute of Virology, Biomedical Research Center, Slovak Academy of Sciences, Dúbravská Cesta 9, 845 05 Bratislava, Slovakia
| | - Lauren Kerr-Jones
- Division of Infection & Immunity, School of Medicine, Cardiff University, Henry Wellcome Building, Heath Park, Cardiff CF14 4XN, UK; (L.K.-J.); (R.J.S.)
| | - Richard J. Stanton
- Division of Infection & Immunity, School of Medicine, Cardiff University, Henry Wellcome Building, Heath Park, Cardiff CF14 4XN, UK; (L.K.-J.); (R.J.S.)
| | - Sebastian Voigt
- University Clinical Center Essen (Universitätsklinikum, AöR), Institute for Virology, Virchowstr. 179, 45147 Essen, Germany;
| | - Friedrich Hahn
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| | - Manfred Marschall
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany; (D.O.); (M.W.); (M.S.); (M.B.D.); (J.K.); (J.T.); (M.K.); (J.L.); (K.D.); (R.M.); (C.W.); (S.W.); (F.H.)
| |
Collapse
|
5
|
Amratia PS, Kerr-Jones LE, Chapman L, Marsden M, Clement M, Stanton RJ, Humphreys IR. Cytomegalovirus-induced peroxynitrite promotes virus entry and contributes to pathogenesis in a murine model of infection. mBio 2024; 15:e0315223. [PMID: 38953361 PMCID: PMC11323495 DOI: 10.1128/mbio.03152-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Accepted: 06/04/2024] [Indexed: 07/04/2024] Open
Abstract
There are no licensed vaccines for human cytomegalovirus (HCMV), and current antiviral drugs that target viral proteins are toxic and prone to resistance. Targeting host pathways essential for virus replication provides an alternate strategy that may reduce opportunities for drug resistance to occur. Oxidative stress is triggered by numerous viruses including HCMV. Peroxynitrite is a reactive nitrogen species that is formed during oxidative stress. Herein, we identified that HCMV rapidly induces the generation of intracellular peroxynitrite upon infection in a manner partially dependent upon xanthine oxidase generation. Peroxynitrite promoted HCMV infection in both cell-free and cell-associated infection systems in multiple cell types. Inhibiting peroxynitrite within the first 24 hours of infection prevented HCMV replication and peroxynitrite promoted cell entry and pp65 translocation into the host cell nuclei. Furthermore, using the murine cytomegalovirus model, we demonstrated that antagonizing peroxynitrite significantly reduces cytomegalovirus replication and pathogenesis in vivo. Overall, our study highlights a proviral role for peroxynitrite in CMV infection and implies that RNS and/or the mechanisms that induce their production could be targeted as a novel strategy to inhibit HCMV infection. IMPORTANCE Human cytomegalovirus (HCMV) causes significant disease in individuals with impaired or immature immune systems, such as transplant patients and after congenital infection. Antiviral drugs that target the virus directly are toxic and are susceptible to antiviral drug resistance due to virus mutations. An alternate strategy is to target processes within host cells that are required by the virus for replication. Herein, we show that HCMV infection triggers a highly reactive molecule, peroxynitrite, during the initial stages of infection. Peroxynitrite was required for the initial entry of the virus into the cell and promotes virus replication in multiple cell types, suggesting a broad pro-viral function. Importantly, targeting peroxynitrite dramatically inhibited cytomegalovirus replication in cells in the laboratory and in mice, suggesting that therapeutic targeting of this molecule and/or the cellular functions it regulates could represent a novel strategy to inhibit HCMV infection.
Collapse
Affiliation(s)
- Pragati S. Amratia
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, United Kingdom
| | - Lauren E. Kerr-Jones
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, United Kingdom
| | - Lucy Chapman
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, United Kingdom
| | - Morgan Marsden
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, United Kingdom
| | - Mathew Clement
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, United Kingdom
| | - Richard J. Stanton
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, United Kingdom
| | - Ian R. Humphreys
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, United Kingdom
| |
Collapse
|
6
|
Tillmanns J, Kicuntod J, Ehring A, Elbasani E, Borst EM, Obergfäll D, Müller R, Hahn F, Marschall M. Establishment of a Luciferase-Based Reporter System to Study Aspects of Human Cytomegalovirus Infection, Replication Characteristics, and Antiviral Drug Efficacy. Pathogens 2024; 13:645. [PMID: 39204245 PMCID: PMC11356942 DOI: 10.3390/pathogens13080645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2024] [Revised: 07/09/2024] [Accepted: 07/25/2024] [Indexed: 09/03/2024] Open
Abstract
Human cytomegalovirus (HCMV) represents a highly medically important pathogen which has constantly been the subject of both molecular and clinical investigations. HCMV infections, especially those in high-risk patients, still raise many unanswered questions, so current investigations are focused on viral pathogenesis, vaccine development, and options for antiviral drug targeting. To this end, the use of suitable viral strains as well as recombinant reporter constructs in cultured cells and model systems has specific significance. We previously reported on the application of various herpesviruses that express green, red, or related fluorescent proteins, especially in the fields of virus-host interaction and antiviral research. Here, we characterized a recombinant version of the clinically relevant and cell type-adaptable HCMV strain TB40, which expresses firefly luciferase as a quantitative reporter of viral replication (TB40-FLuc). The data provide evidence for five main conclusions. First, HCMV TB40-FLuc is employable in multiple settings in primary human cells. Second, viral reporter signals are easily quantifiable, even at early time points within viral replication. Third, the FLuc reporter reflects the kinetics of viral intracellular replication, cascade-like viral IE-E-L protein production, and progeny release. Fourth, as relates to specific applications of the TB40-FLuc system, we demonstrated the reliability of quantitative antiviral compound determination in multi-well formats and its independence from fluorescence-based measurements in the case of autofluorescent inhibitors. Finally, we illustrated increased reporter sensitivity in comparison to other recombinant HCMVs. In essence, recombinant HCMV TB40-FLuc combines several molecular properties that are considered beneficial in studies on viral host tropism, replication efficiency, and antiviral drug assessment.
Collapse
Affiliation(s)
- Julia Tillmanns
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (J.T.); (J.K.); (A.E.); (D.O.); (R.M.); (F.H.)
| | - Jintawee Kicuntod
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (J.T.); (J.K.); (A.E.); (D.O.); (R.M.); (F.H.)
| | - Antonia Ehring
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (J.T.); (J.K.); (A.E.); (D.O.); (R.M.); (F.H.)
| | - Endrit Elbasani
- Institute of Virology, Hannover Medical School (MHH), 30625 Hannover, Germany; (E.E.); (E.M.B.)
| | - Eva Maria Borst
- Institute of Virology, Hannover Medical School (MHH), 30625 Hannover, Germany; (E.E.); (E.M.B.)
| | - Debora Obergfäll
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (J.T.); (J.K.); (A.E.); (D.O.); (R.M.); (F.H.)
| | - Regina Müller
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (J.T.); (J.K.); (A.E.); (D.O.); (R.M.); (F.H.)
| | - Friedrich Hahn
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (J.T.); (J.K.); (A.E.); (D.O.); (R.M.); (F.H.)
| | - Manfred Marschall
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (J.T.); (J.K.); (A.E.); (D.O.); (R.M.); (F.H.)
| |
Collapse
|
7
|
Cimato G, Zhou X, Brune W, Frascaroli G. Human cytomegalovirus glycoprotein variants governing viral tropism and syncytium formation in epithelial cells and macrophages. J Virol 2024; 98:e0029324. [PMID: 38837351 PMCID: PMC11265420 DOI: 10.1128/jvi.00293-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 05/02/2024] [Indexed: 06/07/2024] Open
Abstract
Human cytomegalovirus (HCMV) displays a broad cell tropism, and the infection of biologically relevant cells such as epithelial, endothelial, and hematopoietic cells supports viral transmission, systemic spread, and pathogenesis in the human host. HCMV strains differ in their ability to infect and replicate in these cell types, but the genetic basis of these differences has remained incompletely understood. In this study, we investigated HCMV strain VR1814, which is highly infectious for epithelial cells and macrophages and induces cell-cell fusion in both cell types. A VR1814-derived bacterial artificial chromosome (BAC) clone, FIX-BAC, was generated many years ago but has fallen out of favor because of its modest infectivity. By sequence comparison and genetic engineering of FIX, we demonstrate that the high infectivity of VR1814 and its ability to induce syncytium formation in epithelial cells and macrophages depends on VR1814-specific variants of the envelope glycoproteins gB, UL128, and UL130. We also show that UL130-neutralizing antibodies inhibit syncytium formation, and a FIX-specific mutation in UL130 is responsible for its low infectivity by reducing the amount of the pentameric glycoprotein complex in viral particles. Moreover, we found that a VR1814-specific mutation in US28 further increases viral infectivity in macrophages, possibly by promoting lytic rather than latent infection of these cells. Our findings show that variants of gB and the pentameric complex are major determinants of infectivity and syncytium formation in epithelial cells and macrophages. Furthermore, the VR1814-adjusted FIX strains can serve as valuable tools to study HCMV infection of myeloid cells.IMPORTANCEHuman cytomegalovirus (HCMV) is a major cause of morbidity and mortality in transplant patients and the leading cause of congenital infections. HCMV infects various cell types, including epithelial cells and macrophages, and some strains induce the fusion of neighboring cells, leading to the formation of large multinucleated cells called syncytia. This process may limit the exposure of the virus to host immune factors and affect pathogenicity. However, the reason why some HCMV strains exhibit a broader cell tropism and why some induce cell fusion more than others is not well understood. We compared two closely related HCMV strains and provided evidence that small differences in viral envelope glycoproteins can massively increase or decrease the virus infectivity and its ability to induce syncytium formation. The results of the study suggest that natural strain variations may influence HCMV infection and pathogenesis in humans.
Collapse
Affiliation(s)
| | - Xuan Zhou
- Leibniz Institute of Virology (LIV), Hamburg, Germany
| | - Wolfram Brune
- Leibniz Institute of Virology (LIV), Hamburg, Germany
| | | |
Collapse
|
8
|
Finkel Y, Nachshon A, Aharon E, Arazi T, Simonovsky E, Dobešová M, Saud Z, Gluck A, Fisher T, Stanton RJ, Schwartz M, Stern-Ginossar N. A virally encoded high-resolution screen of cytomegalovirus dependencies. Nature 2024; 630:712-719. [PMID: 38839957 DOI: 10.1038/s41586-024-07503-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 05/01/2024] [Indexed: 06/07/2024]
Abstract
Genetic screens have transformed our ability to interrogate cellular factor requirements for viral infections1,2, but most current approaches are limited in their sensitivity, biased towards early stages of infection and provide only simplistic phenotypic information that is often based on survival of infected cells2-4. Here, by engineering human cytomegalovirus to express single guide RNA libraries directly from the viral genome, we developed virus-encoded CRISPR-based direct readout screening (VECOS), a sensitive, versatile, viral-centric approach that enables profiling of different stages of viral infection in a pooled format. Using this approach, we identified hundreds of host dependency and restriction factors and quantified their direct effects on viral genome replication, viral particle secretion and infectiousness of secreted particles, providing a multi-dimensional perspective on virus-host interactions. These high-resolution measurements reveal that perturbations altering late stages in the life cycle of human cytomegalovirus (HCMV) mostly regulate viral particle quality rather than quantity, establishing correct virion assembly as a critical stage that is heavily reliant on virus-host interactions. Overall, VECOS facilitates systematic high-resolution dissection of the role of human proteins during the infection cycle, providing a roadmap for in-depth study of host-herpesvirus interactions.
Collapse
Affiliation(s)
- Yaara Finkel
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Aharon Nachshon
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Einav Aharon
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Tamar Arazi
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Elena Simonovsky
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Martina Dobešová
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Zack Saud
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK
| | - Avi Gluck
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Tal Fisher
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Richard J Stanton
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK
| | - Michal Schwartz
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel.
| | - Noam Stern-Ginossar
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel.
| |
Collapse
|
9
|
Li H, Fletcher-Etherington A, Hunter LM, Keshri S, Fielding CA, Nightingale K, Ravenhill B, Nobre L, Potts M, Antrobus R, Crump CM, Rubinsztein DC, Stanton RJ, Weekes MP. Human cytomegalovirus degrades DMXL1 to inhibit autophagy, lysosomal acidification, and viral assembly. Cell Host Microbe 2024; 32:466-478.e11. [PMID: 38479395 DOI: 10.1016/j.chom.2024.02.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 01/10/2024] [Accepted: 02/20/2024] [Indexed: 04/13/2024]
Abstract
Human cytomegalovirus (HCMV) is an important human pathogen that regulates host immunity and hijacks host compartments, including lysosomes, to assemble virions. We combined a quantitative proteomic analysis of HCMV infection with a database of proteins involved in vacuolar acidification, revealing Dmx-like protein-1 (DMXL1) as the only protein that acidifies vacuoles yet is degraded by HCMV. Systematic comparison of viral deletion mutants reveals the uncharacterized 7 kDa US33A protein as necessary and sufficient for DMXL1 degradation, which occurs via recruitment of the E3 ubiquitin ligase Kip1 ubiquitination-promoting complex (KPC). US33A-mediated DMXL1 degradation inhibits lysosome acidification and autophagic cargo degradation. Formation of the virion assembly compartment, which requires lysosomes, occurs significantly later with US33A-expressing virus infection, with reduced viral replication. These data thus identify a viral strategy for cellular remodeling, with the potential to employ US33A in therapies for viral infection or rheumatic conditions, in which inhibition of lysosome acidification can attenuate disease.
Collapse
Affiliation(s)
- Hanqi Li
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK; Department of Medicine, University of Cambridge, Hills Road, Cambridge CB2 2QQ, UK
| | - Alice Fletcher-Etherington
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK; Department of Medicine, University of Cambridge, Hills Road, Cambridge CB2 2QQ, UK
| | - Leah M Hunter
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK; Department of Medicine, University of Cambridge, Hills Road, Cambridge CB2 2QQ, UK
| | - Swati Keshri
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Institute, University of Cambridge, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
| | - Ceri A Fielding
- Cardiff University School of Medicine, Division of Infection and Immunity, Henry Wellcome Building, Heath Park, Cardiff CF14 4XN, UK
| | - Katie Nightingale
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK; Department of Medicine, University of Cambridge, Hills Road, Cambridge CB2 2QQ, UK
| | - Benjamin Ravenhill
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK; Department of Medicine, University of Cambridge, Hills Road, Cambridge CB2 2QQ, UK
| | - Luis Nobre
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK; Department of Medicine, University of Cambridge, Hills Road, Cambridge CB2 2QQ, UK
| | - Martin Potts
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK; Department of Medicine, University of Cambridge, Hills Road, Cambridge CB2 2QQ, UK
| | - Robin Antrobus
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK; Department of Medicine, University of Cambridge, Hills Road, Cambridge CB2 2QQ, UK
| | - Colin M Crump
- Division of Virology, Department of Pathology, University of Cambridge, Cambridge, UK
| | - David C Rubinsztein
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK; UK Dementia Institute, University of Cambridge, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
| | - Richard J Stanton
- Cardiff University School of Medicine, Division of Infection and Immunity, Henry Wellcome Building, Heath Park, Cardiff CF14 4XN, UK
| | - Michael P Weekes
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK.
| |
Collapse
|
10
|
Hunter LM, Kite J, Fletcher-Etherington A, Nightingale K, Nobre L, Antrobus R, Fielding CA, Stanton RJ, Weekes MP. HCMV US2 co-opts TRC8 to degrade the endoplasmic reticulum-resident protein LMAN2L. J Gen Virol 2024; 105:001980. [PMID: 38687323 PMCID: PMC11083459 DOI: 10.1099/jgv.0.001980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 04/12/2024] [Indexed: 05/02/2024] Open
Abstract
The human cytomegalovirus (HCMV) pUS2 glycoprotein exploits the host's endoplasmic reticulum (ER)-associated degradation (ERAD) pathway to degrade major histocompatibility complex class I (MHC-I) and prevent antigen presentation. Beyond MHC-I, pUS2 has been shown to target a range of cellular proteins for degradation, preventing their cell surface expression. Here we have identified a novel pUS2 target, ER-resident protein lectin mannose binding 2 like (LMAN2L). pUS2 expression was both necessary and sufficient for the downregulation of LMAN2L, which was dependent on the cellular E3 ligase TRC8. Given the hypothesized role of LMAN2L in the trafficking of glycoproteins, we employed proteomic plasma membrane profiling to measure LMAN2L-dependent changes at the cell surface. A known pUS2 target, integrin alpha-6 (ITGA6), was downregulated from the surface of LMAN2L-deficient cells, but not other integrins. Overall, these results suggest a novel strategy of pUS2-mediated protein degradation whereby pUS2 targets LMAN2L to impair trafficking of ITGA6. Given that pUS2 can directly target other integrins, we propose that this single viral protein may exhibit both direct and indirect mechanisms to downregulate key cell surface molecules.
Collapse
Affiliation(s)
- Leah M. Hunter
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
- Department of Medicine, University of Cambridge, Hills Road, Cambridge, CB2 2QQ, UK
| | - Joanne Kite
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
- Department of Medicine, University of Cambridge, Hills Road, Cambridge, CB2 2QQ, UK
| | - Alice Fletcher-Etherington
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
- Department of Medicine, University of Cambridge, Hills Road, Cambridge, CB2 2QQ, UK
| | - Katie Nightingale
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
- Department of Medicine, University of Cambridge, Hills Road, Cambridge, CB2 2QQ, UK
| | - Luis Nobre
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
- Department of Medicine, University of Cambridge, Hills Road, Cambridge, CB2 2QQ, UK
| | - Robin Antrobus
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
- Department of Medicine, University of Cambridge, Hills Road, Cambridge, CB2 2QQ, UK
| | - Ceri A. Fielding
- Cardiff University School of Medicine, Division of Infection and Immunity, Henry Wellcome Building, Heath Park, Cardiff CF14 4XN, UK
| | - Richard J. Stanton
- Cardiff University School of Medicine, Division of Infection and Immunity, Henry Wellcome Building, Heath Park, Cardiff CF14 4XN, UK
| | - Michael P. Weekes
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
- Department of Medicine, University of Cambridge, Hills Road, Cambridge, CB2 2QQ, UK
| |
Collapse
|
11
|
Chesnokova LS, Mosher BS, Fulkerson HL, Nam HW, Shakya AK, Yurochko AD. Distinct early role of PTEN regulation during HCMV infection of monocytes. Proc Natl Acad Sci U S A 2024; 121:e2312290121. [PMID: 38483999 PMCID: PMC10962971 DOI: 10.1073/pnas.2312290121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 12/01/2023] [Indexed: 03/19/2024] Open
Abstract
Human cytomegalovirus (HCMV) infection of monocytes is essential for viral dissemination and persistence. We previously identified that HCMV entry/internalization and subsequent productive infection of this clinically relevant cell type is distinct when compared to other infected cells. We showed that internalization and productive infection required activation of epidermal growth factor receptor (EGFR) and integrin/c-Src, via binding of viral glycoprotein B to EGFR, and the pentamer complex to β1/β3 integrins. To understand how virus attachment drives entry, we compared infection of monocytes with viruses containing the pentamer vs. those without the pentamer and then used a phosphoproteomic screen to identify potential phosphorylated proteins that influence HCMV entry and trafficking. The screen revealed that the most prominent pentamer-biased phosphorylated protein was the lipid- and protein-phosphatase phosphatase and tensin homolog (PTEN). PTEN knockdown with siRNA or PTEN inhibition with a PTEN inhibitor decreased pentamer-mediated HCMV entry, without affecting trimer-mediated entry. Inhibition of PTEN activity affected lipid metabolism and interfered with the onset of the endocytic processes required for HCMV entry. PTEN inactivation was sufficient to rescue pentamer-null HCMV from lysosomal degradation. We next examined dephosphorylation of a PTEN substrate Rab7, a regulator of endosomal maturation. Inhibition of PTEN activity prevented dephosphorylation of Rab7. Phosphorylated Rab7, in turn, blocked early endosome to late endosome maturation and promoted nuclear localization of the virus and productive infection.
Collapse
Affiliation(s)
- Liudmila S. Chesnokova
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA71103
- Center for Applied Immunology and Pathological Processes, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA71103
| | - Bailey S. Mosher
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA71103
- Center for Applied Immunology and Pathological Processes, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA71103
| | - Heather L. Fulkerson
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA71103
- Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA71103
| | - Hyung W. Nam
- Department of Pharmacology, Toxicology, and Neuroscience, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA71103
| | - Akhalesh K. Shakya
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA71103
| | - Andrew D. Yurochko
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA71103
- Center for Applied Immunology and Pathological Processes, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA71103
- Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA71103
- Feist-Weller Cancer Center, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA 71103, Shreveport, LA71103
- Center for Excellence in Arthritis and Rheumatology, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA71103
- Center of Excellence for Emerging Viral Threats, Louisiana State University Health Sciences Center Shreveport, Shreveport, LA71103
| |
Collapse
|
12
|
Otero CE, Petkova S, Ebermann M, Taher H, John N, Hoffmann K, Davalos A, Moström MJ, Gilbride RM, Papen CR, Barber-Axthelm A, Scheef EA, Barfield R, Sprehe LM, Kendall S, Manuel TD, Vande Burgt NH, Chan C, Denton M, Streblow ZJ, Streblow DN, Hansen SG, Kaur A, Permar S, Früh K, Hengel H, Malouli D, Kolb P. Rhesus Cytomegalovirus-encoded Fcγ-binding glycoproteins facilitate viral evasion from IgG-mediated humoral immunity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.27.582371. [PMID: 38464092 PMCID: PMC10925275 DOI: 10.1101/2024.02.27.582371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Human cytomegalovirus (HCMV) encodes four viral Fc-gamma receptors (vFcγRs) that counteract antibody-mediated activation in vitro , but their role in infection and pathogenesis is unknown. To examine the in vivo function of vFcγRs in animal hosts closely related to humans, we identified and characterized vFcγRs encoded by rhesus CMV (RhCMV). We demonstrate that Rh05, Rh152/151 and Rh173 represent the complete set of RhCMV vFcγRs, each displaying functional similarities to their respective HCMV orthologs with respect to antagonizing host FcγR activation in vitro . When RhCMV-naïve rhesus macaques were infected with vFcγR-deleted RhCMV, peak plasma viremia levels and anti-RhCMV antibody responses were comparable to wildtype infections. However, the duration of plasma viremia was significantly shortened in immunocompetent, but not in CD4+ T cell-depleted animals. Since vFcγRs were not required for superinfection, we conclude that vFcγRs delay control by virus-specific adaptive immune responses, particularly antibodies, during primary infection.
Collapse
|
13
|
Gerna G, Lilleri D, Fornara C, d'Angelo P, Baldanti F. Relationship of human cytomegalovirus-infected endothelial cells and circulating leukocytes in the pathogenesis of disseminated human cytomegalovirus infection: A narrative review. Rev Med Virol 2024; 34:e2496. [PMID: 38282408 DOI: 10.1002/rmv.2496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 10/12/2023] [Accepted: 11/26/2023] [Indexed: 01/30/2024]
Abstract
Among the leucocyte subpopulations circulating in peripheral blood of immune-compromised patients with disseminated Human cytomegalovirus (HCMV) infection, polymorphonuclear leuckocytes (PMNL) and M/M may carry infectious virus. While only in PMNL early HCMV replicative events do occur, monocytes are susceptible to complete virus replication when they enter human organs, where as macrophages become a site of active complete virus replication. In vivo leucocytes and endothelial cells interact continuously, as suggested by several in vitro experimental findings showing the bidirectional HCMV transmission from leucocytes to and from endothelial cells with the critical aid of adhesion molecules. Recently, the neutralising antibody response in sera from subjects with primary HCMV infection was reported to be much higher and earlier than in human embryonic lung fibroblasts (HELF) cells when measured in endothelial cells and epithelial cells, where virus entry is mediated mostly by the pentamer complex gH/gL/pUL128/pUL130/pUL131, whereas it was much lower and delayed when determined in HELF, where virus entry is mediated mostly by the trimer complex gH/gL/gO. Thus, these results suggested that products of UL128L were the molecules primary responsible for the differential neutralising antibody response. This conclusion was confirmed by a series of polyclonal and monoclonal antibodies directed to the components of pUL128L. Very recently, based on two sets of experiments including inhibition and immunoblotting assays, the pentamer complex/trimer complex ratio has been finally identified as the main factor of the neutralising antibody response. This ratio may change with the virus suspension producer and target cell system as well as number of cell culture passages.
Collapse
Affiliation(s)
- Giuseppe Gerna
- Centre for Inherited Cardiovascular Diseases, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Daniele Lilleri
- Microbiology and Virology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Chiara Fornara
- Laboratory Medicine Service, Istituti Clinici Scientifici Maugeri IRCCS, Pavia, Italy
| | - Piera d'Angelo
- Microbiology and Virology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Fausto Baldanti
- Microbiology and Virology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
- Department of Clinical, Surgical, Diagnostic and Pediatric Sciences, University of Pavia, Pavia, Italy
| |
Collapse
|
14
|
Golconda P, Andrade-Medina M, Oberstein A. Subconfluent ARPE-19 Cells Display Mesenchymal Cell-State Characteristics and Behave like Fibroblasts, Rather Than Epithelial Cells, in Experimental HCMV Infection Studies. Viruses 2023; 16:49. [PMID: 38257749 PMCID: PMC10821009 DOI: 10.3390/v16010049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 12/20/2023] [Accepted: 12/25/2023] [Indexed: 01/24/2024] Open
Abstract
Human cytomegalovirus (HCMV) has a broad cellular tropism and epithelial cells are important physiological targets during infection. The retinal pigment epithelial cell line ARPE-19 has been used to model HCMV infection in epithelial cells for decades and remains a commonly used cell type for studying viral entry, replication, and the cellular response to infection. We previously found that ARPE-19 cells, despite being derived from an epithelial cell explant, express extremely low levels of canonical epithelial proteins, such as E-cadherin and EpCAM. Here, we perform comparative studies of ARPE-19 and additional epithelial cell lines with strong epithelial characteristics. We find that ARPE-19 cells cultured under subconfluent conditions resemble mesenchymal fibroblasts, rather than epithelial cells; this is consistent with previous studies showing that ARPE-19 cultures require extended periods of high confluency culture to maintain epithelial characteristics. By reanalyzing public gene expression data and using machine learning, we find evidence that ARPE-19 cultures maintained across many labs exhibit mesenchymal characteristics and that the majority of studies employing ARPE-19 use them in a mesenchymal state. Lastly, by performing experimental HCMV infections across mesenchymal and epithelial cell lines, we find that ARPE-19 cells behave like mesenchymal fibroblasts, producing logarithmic yields of cell-free infectious progeny, while cell lines with strong epithelial character exhibit an atypical infectious cycle and naturally restrict the production of cell-free progeny. Our work highlights important characteristics of the ARPE-19 cell line and suggests that subconfluent ARPE-19 cells may not be optimal for modeling epithelial infection with HCMV or other human viruses. It also suggests that HCMV biosynthesis and/or spread may occur quite differently in epithelial cells compared to mesenchymal cells. These differences could contribute to viral persistence or pathogenesis in epithelial tissues.
Collapse
Affiliation(s)
| | | | - Adam Oberstein
- Department of Microbiology and Immunology, College of Medicine, University of Illinois at Chicago, 835 South Wolcott Ave., Chicago, IL 60612, USA; (P.G.); (M.A.-M.)
| |
Collapse
|
15
|
Vlachava VM, Seirafian S, Fielding CA, Kollnberger S, Aicheler RJ, Hughes J, Baker A, Weekes MP, Forbes S, Wilkinson GWG, Wang ECY, Stanton RJ. HCMV-secreted glycoprotein gpUL4 inhibits TRAIL-mediated apoptosis and NK cell activation. Proc Natl Acad Sci U S A 2023; 120:e2309077120. [PMID: 38011551 PMCID: PMC10710050 DOI: 10.1073/pnas.2309077120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 10/07/2023] [Indexed: 11/29/2023] Open
Abstract
Human cytomegalovirus (HCMV) is a paradigm of pathogen immune evasion and sustains lifelong persistent infection in the face of exceptionally powerful host immune responses through the concerted action of multiple immune-evasins. These reduce NK cell activation by inhibiting ligands for activating receptors, expressing ligands for inhibitory receptors, or inhibiting synapse formation. However, these functions only inhibit direct interactions with the infected cell. To determine whether the virus also expresses soluble factors that could modulate NK function at a distance, we systematically screened all 170 HCMV canonical protein-coding genes. This revealed that UL4 encodes a secreted and heavily glycosylated protein (gpUL4) that is expressed with late-phase kinetics and is capable of inhibiting NK cell degranulation. Analyses of gpUL4 binding partners by mass spectrometry identified an interaction with TRAIL. gpUL4 bound TRAIL with picomolar affinity and prevented TRAIL from binding its receptor, thus acting as a TRAIL decoy receptor. TRAIL is found in both soluble and membrane-bound forms, with expression of the membrane-bound form strongly up-regulated on NK cells in response to interferon. gpUL4 inhibited apoptosis induced by soluble TRAIL, while also binding to the NK cell surface in a TRAIL-dependent manner, where it blocked NK cell degranulation and cytokine secretion. gpUL4 therefore acts as an immune-evasin by inhibiting both soluble and membrane-bound TRAIL and is a viral-encoded TRAIL decoy receptor. Interestingly, gpUL4 could also suppress NK responses to heterologous viruses, suggesting that it may act as a systemic virally encoded immunosuppressive agent.
Collapse
Affiliation(s)
- Virginia-Maria Vlachava
- Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Sepehr Seirafian
- Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Ceri A. Fielding
- Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Simon Kollnberger
- Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Rebecca J. Aicheler
- Department of Biomedical Sciences, Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, CardiffCF5 2YB, United Kingdom
| | - Joseph Hughes
- Centre for Virus Research, School of Infection & Immunity, Glasgow University, GlasgowG61 1QH, United Kingdom
| | - Alexander Baker
- Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Michael P. Weekes
- Cambridge Institute for Medical Research, Department of Medicine, University of Cambridge, CambridgeCB2 0XY, United Kingdom
| | - Simone Forbes
- Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Gavin W. G. Wilkinson
- Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Eddie C. Y. Wang
- Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Richard J. Stanton
- Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| |
Collapse
|
16
|
Chowdhury S, Latham KA, Tran AC, Carroll CJ, Stanton RJ, Weekes MP, Neil SJD, Swanson CM, Strang BL. Inhibition of human cytomegalovirus replication by interferon alpha can involve multiple anti-viral factors. J Gen Virol 2023; 104:001929. [PMID: 38063292 PMCID: PMC10770924 DOI: 10.1099/jgv.0.001929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 11/21/2023] [Indexed: 12/18/2023] Open
Abstract
The shortcomings of current direct-acting anti-viral therapy against human cytomegalovirus (HCMV) has led to interest in host-directed therapy. Here we re-examine the use of interferon proteins to inhibit HCMV replication utilizing both high and low passage strains of HCMV. Pre-treatment of cells with interferon alpha (IFNα) was required for robust and prolonged inhibition of both low and high passage HCMV strains, with no obvious toxicity, and was associated with an increased anti-viral state in HCMV-infected cells. Pre-treatment of cells with IFNα led to poor expression of HCMV immediate-early proteins from both high and low passage strains, which was associated with the presence of the anti-viral factor SUMO-PML. Inhibition of HCMV replication in the presence of IFNα involving ZAP proteins was HCMV strain-dependent, wherein a high passage HCMV strain was obviously restricted by ZAP and a low passage strain was not. This suggested that strain-specific combinations of anti-viral factors were involved in inhibition of HCMV replication in the presence of IFNα. Overall, this work further supports the development of strategies involving IFNα that may be useful to inhibit HCMV replication and highlights the complexity of the anti-viral response to HCMV in the presence of IFNα.
Collapse
Affiliation(s)
- Shabab Chowdhury
- Institute of Infection & Immunity, St George’s, University of London, London, UK
| | - Katie A. Latham
- Institute of Infection & Immunity, St George’s, University of London, London, UK
| | - Andy C. Tran
- Institute of Infection & Immunity, St George’s, University of London, London, UK
| | - Christopher J. Carroll
- Institute of Molecular & Cellular Sciences, St George’s, University of London, London, UK
| | - Richard J. Stanton
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK
| | - Michael P. Weekes
- Cambridge Institute for Medical Research, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Stuart J. D. Neil
- Department of Infectious Diseases, School of Immunology & Microbial Sciences, King’s College London, London, UK
| | - Chad M. Swanson
- Department of Infectious Diseases, School of Immunology & Microbial Sciences, King’s College London, London, UK
| | - Blair L. Strang
- Institute of Infection & Immunity, St George’s, University of London, London, UK
| |
Collapse
|
17
|
Zehner M, Alt M, Ashurov A, Goldsmith JA, Spies R, Weiler N, Lerma J, Gieselmann L, Stöhr D, Gruell H, Schultz EP, Kreer C, Schlachter L, Janicki H, Laib Sampaio K, Stegmann C, Nemetchek MD, Dähling S, Ullrich L, Dittmer U, Witzke O, Koch M, Ryckman BJ, Lotfi R, McLellan JS, Krawczyk A, Sinzger C, Klein F. Single-cell analysis of memory B cells from top neutralizers reveals multiple sites of vulnerability within HCMV Trimer and Pentamer. Immunity 2023; 56:2602-2620.e10. [PMID: 37967532 DOI: 10.1016/j.immuni.2023.10.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 07/02/2023] [Accepted: 10/18/2023] [Indexed: 11/17/2023]
Abstract
Human cytomegalovirus (HCMV) can cause severe diseases in fetuses, newborns, and immunocompromised individuals. Currently, no vaccines are approved, and treatment options are limited. Here, we analyzed the human B cell response of four HCMV top neutralizers from a cohort of 9,000 individuals. By single-cell analyses of memory B cells targeting the pentameric and trimeric HCMV surface complexes, we identified vulnerable sites on the shared gH/gL subunits as well as complex-specific subunits UL128/130/131A and gO. Using high-resolution cryogenic electron microscopy, we revealed the structural basis of the neutralization mechanisms of antibodies targeting various binding sites. Moreover, we identified highly potent antibodies that neutralized a broad spectrum of HCMV strains, including primary clinical isolates, that outperform known antibodies used in clinical trials. Our study provides a deep understanding of the mechanisms of HCMV neutralization and identifies promising antibody candidates to prevent and treat HCMV infection.
Collapse
Affiliation(s)
- Matthias Zehner
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany.
| | - Mira Alt
- Department of Infectious Diseases, West German Centre of Infectious Diseases, University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany
| | - Artem Ashurov
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Jory A Goldsmith
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Rebecca Spies
- Institute for Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Nina Weiler
- Institute for Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Justin Lerma
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Lutz Gieselmann
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany; German Center for Infection Research, Partner Site Bonn-Cologne, 50931 Cologne, Germany
| | - Dagmar Stöhr
- Institute for Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Henning Gruell
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Eric P Schultz
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA; Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT 59812, USA
| | - Christoph Kreer
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Linda Schlachter
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Hanna Janicki
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | | | - Cora Stegmann
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA; Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT 59812, USA
| | - Michelle D Nemetchek
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA; Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT 59812, USA
| | - Sabrina Dähling
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Leon Ullrich
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Ulf Dittmer
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany
| | - Oliver Witzke
- Department of Infectious Diseases, West German Centre of Infectious Diseases, University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany
| | - Manuel Koch
- Institute for Dental Research and Oral Musculoskeletal Biology, Center for Biochemistry, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Brent J Ryckman
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA; Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT 59812, USA
| | - Ramin Lotfi
- Institute for Transfusion Medicine, Ulm University Medical Center, 89081 Ulm, Germany
| | - Jason S McLellan
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Adalbert Krawczyk
- Department of Infectious Diseases, West German Centre of Infectious Diseases, University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany; Institute for Virology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany
| | - Christian Sinzger
- Institute for Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Florian Klein
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany; German Center for Infection Research, Partner Site Bonn-Cologne, 50931 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University Hospital of Cologne, 50931 Cologne, Germany.
| |
Collapse
|
18
|
Weiler N, Sampaio KL, Scherer M, Sinzger C. Generation of UL128-shRNA transduced fibroblasts for the release of cell-free virus from clinical human cytomegalovirus isolates. Biotechniques 2023; 75:183-194. [PMID: 37846844 DOI: 10.2144/btn-2023-0046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2023] Open
Abstract
Working with recent isolates of human cytomegalovirus (HCMV) is complicated by their strictly cell-associated growth with lack of infectivity in the supernatant. Adaptation to cell-free growth is associated with disruption of the viral UL128 gene locus. The authors transduced fibroblasts with a lentiviral vector encoding UL128-specific-shRNA to allow the release of cell-free infectivity without genetic alteration. Transduced cells were cocultured with fibroblasts containing cell-associated isolates, and knockdown of the UL128 protein was validated by immunoblotting. Cell-free infectivity increased 1000-fold in isolate cocultures with UL128-shRNA compared with controls, and virions could be purified by density gradients. Transduced fibroblasts also allowed direct isolation of HCMV from a clinical specimen and cell-free transfer to other cell types. In conclusion, UL128-shRNA-transduced fibroblasts allow applications previously unsuitable for recent isolates.
Collapse
Affiliation(s)
- Nina Weiler
- Institute of Virology, Ulm University Medical Center, Ulm, Germany
| | | | - Myriam Scherer
- Institute of Virology, Ulm University Medical Center, Ulm, Germany
| | | |
Collapse
|
19
|
Bebelman MP, Setiawan IM, Bergkamp ND, van Senten JR, Crudden C, Bebelman JPM, Verweij FJ, van Niel G, Siderius M, Pegtel DM, Smit MJ. Exosomal release of the virus-encoded chemokine receptor US28 contributes to chemokine scavenging. iScience 2023; 26:107412. [PMID: 37575190 PMCID: PMC10415803 DOI: 10.1016/j.isci.2023.107412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 06/22/2023] [Accepted: 07/14/2023] [Indexed: 08/15/2023] Open
Abstract
The human cytomegalovirus (HCMV)-encoded chemokine receptor US28 contributes to various aspects of the viral life cycle and promotes immune evasion by scavenging chemokines from the microenvironment of HCMV-infected cells. In contrast to the plasma membrane localization of most human chemokine receptors, US28 has a predominant intracellular localization. In this study, we used immunofluorescence and electron microscopy to determine the localization of US28 upon exogenous expression, as well as in HCMV-infected cells. We observed that US28 localizes to late endosomal compartments called multivesicular bodies (MVBs), where it is sorted in intraluminal vesicles. Live-cell total internal reflection fluorescence (TIRF) microscopy revealed that US28-containing MVBs can fuse with the plasma membrane, resulting in the secretion of US28 on exosomes. Exosomal US28 binds the chemokines CX3CL1 and CCL5, and US28-containing exosomes inhibited the CX3CL1-CX3CR1 signaling axis. These findings suggest that exosomal release of US28 contributes to chemokine scavenging and immune evasion by HCMV.
Collapse
Affiliation(s)
- Maarten P. Bebelman
- Division of Medicinal Chemistry, Amsterdam Institute for Molecular and Life Sciences, Vrije Universiteit Amsterdam, de Boelelaan 1108, 1081 HZ Amsterdam, the Netherlands
- Department Pathology, Cancer Center Amsterdam, VU University Medical Center, de Boelelaan 1118, Amsterdam 1081 HZ, the Netherlands
| | - Irfan M. Setiawan
- Division of Medicinal Chemistry, Amsterdam Institute for Molecular and Life Sciences, Vrije Universiteit Amsterdam, de Boelelaan 1108, 1081 HZ Amsterdam, the Netherlands
| | - Nick D. Bergkamp
- Division of Medicinal Chemistry, Amsterdam Institute for Molecular and Life Sciences, Vrije Universiteit Amsterdam, de Boelelaan 1108, 1081 HZ Amsterdam, the Netherlands
| | - Jeffrey R. van Senten
- Division of Medicinal Chemistry, Amsterdam Institute for Molecular and Life Sciences, Vrije Universiteit Amsterdam, de Boelelaan 1108, 1081 HZ Amsterdam, the Netherlands
| | - Caitrin Crudden
- Division of Medicinal Chemistry, Amsterdam Institute for Molecular and Life Sciences, Vrije Universiteit Amsterdam, de Boelelaan 1108, 1081 HZ Amsterdam, the Netherlands
- Department Pathology, Cancer Center Amsterdam, VU University Medical Center, de Boelelaan 1118, Amsterdam 1081 HZ, the Netherlands
| | - Jan Paul M. Bebelman
- Division of Medicinal Chemistry, Amsterdam Institute for Molecular and Life Sciences, Vrije Universiteit Amsterdam, de Boelelaan 1108, 1081 HZ Amsterdam, the Netherlands
| | - Frederik J. Verweij
- Division of Cell Biology, Neurobiology and Biophysics, Utrecht University, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Guillaume van Niel
- Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266 Université de Paris, Paris, France
| | - Marco Siderius
- Division of Medicinal Chemistry, Amsterdam Institute for Molecular and Life Sciences, Vrije Universiteit Amsterdam, de Boelelaan 1108, 1081 HZ Amsterdam, the Netherlands
| | - D. Michiel Pegtel
- Department Pathology, Cancer Center Amsterdam, VU University Medical Center, de Boelelaan 1118, Amsterdam 1081 HZ, the Netherlands
| | - Martine J. Smit
- Division of Medicinal Chemistry, Amsterdam Institute for Molecular and Life Sciences, Vrije Universiteit Amsterdam, de Boelelaan 1108, 1081 HZ Amsterdam, the Netherlands
| |
Collapse
|
20
|
Rubina A, Patel M, Nightingale K, Potts M, Fielding CA, Kollnberger S, Lau B, Ladell K, Miners KL, Nichols J, Nobre L, Roberts D, Trinca TM, Twohig JP, Vlahava VM, Davison AJ, Price DA, Tomasec P, Wilkinson GWG, Weekes MP, Stanton RJ, Wang ECY. ADAM17 targeting by human cytomegalovirus remodels the cell surface proteome to simultaneously regulate multiple immune pathways. Proc Natl Acad Sci U S A 2023; 120:e2303155120. [PMID: 37561786 PMCID: PMC10438378 DOI: 10.1073/pnas.2303155120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 06/23/2023] [Indexed: 08/12/2023] Open
Abstract
Human cytomegalovirus (HCMV) is a major human pathogen whose life-long persistence is enabled by its remarkable capacity to systematically subvert host immune defenses. In exploring the finding that HCMV infection up-regulates tumor necrosis factor receptor 2 (TNFR2), a ligand for the pro-inflammatory antiviral cytokine TNFα, we found that the underlying mechanism was due to targeting of the protease, A Disintegrin And Metalloproteinase 17 (ADAM17). ADAM17 is the prototype 'sheddase', a family of proteases that cleaves other membrane-bound proteins to release biologically active ectodomains into the supernatant. HCMV impaired ADAM17 surface expression through the action of two virally-encoded proteins in its UL/b' region, UL148 and UL148D. Proteomic plasma membrane profiling of cells infected with an HCMV double-deletion mutant for UL148 and UL148D with restored ADAM17 expression, combined with ADAM17 functional blockade, showed that HCMV stabilized the surface expression of 114 proteins (P < 0.05) in an ADAM17-dependent fashion. These included reported substrates of ADAM17 with established immunological functions such as TNFR2 and jagged1, but also numerous unreported host and viral targets, such as nectin1, UL8, and UL144. Regulation of TNFα-induced cytokine responses and NK inhibition during HCMV infection were dependent on this impairment of ADAM17. We therefore identify a viral immunoregulatory mechanism in which targeting a single sheddase enables broad regulation of multiple critical surface receptors, revealing a paradigm for viral-encoded immunomodulation.
Collapse
Affiliation(s)
- Anzelika Rubina
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Mihil Patel
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Katie Nightingale
- Cambridge Institute for Medical Research, University of Cambridge, CambridgeCB2 0XY, United Kingdom
| | - Martin Potts
- Cambridge Institute for Medical Research, University of Cambridge, CambridgeCB2 0XY, United Kingdom
- Department of Medicine, University of Cambridge, CambridgeCB2 0XY, United Kingdom
| | - Ceri A. Fielding
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Simon Kollnberger
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Betty Lau
- Centre for Virus Research, University of Glasgow, GlasgowG12 8TA, United Kingdom
| | - Kristin Ladell
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Kelly L. Miners
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Jenna Nichols
- Centre for Virus Research, University of Glasgow, GlasgowG12 8TA, United Kingdom
| | - Luis Nobre
- Cambridge Institute for Medical Research, University of Cambridge, CambridgeCB2 0XY, United Kingdom
| | - Dawn Roberts
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Terrence M. Trinca
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Jason P. Twohig
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Virginia-Maria Vlahava
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Andrew J. Davison
- Centre for Virus Research, University of Glasgow, GlasgowG12 8TA, United Kingdom
| | - David A. Price
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Peter Tomasec
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Gavin W. G. Wilkinson
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Michael P. Weekes
- Cambridge Institute for Medical Research, University of Cambridge, CambridgeCB2 0XY, United Kingdom
- Department of Medicine, University of Cambridge, CambridgeCB2 0XY, United Kingdom
| | - Richard J. Stanton
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| | - Eddie C. Y. Wang
- Division of Infection and Immunity, School of Medicine, Cardiff University, CardiffCF14 4XN, United Kingdom
| |
Collapse
|
21
|
Zeng J, Cao D, Yang S, Jaijyan DK, Liu X, Wu S, Cruz-Cosme R, Tang Q, Zhu H. Insights into the Transcriptome of Human Cytomegalovirus: A Comprehensive Review. Viruses 2023; 15:1703. [PMID: 37632045 PMCID: PMC10458407 DOI: 10.3390/v15081703] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 08/03/2023] [Accepted: 08/04/2023] [Indexed: 08/27/2023] Open
Abstract
Human cytomegalovirus (HCMV) is a widespread pathogen that poses significant risks to immunocompromised individuals. Its genome spans over 230 kbp and potentially encodes over 200 open-reading frames. The HCMV transcriptome consists of various types of RNAs, including messenger RNAs (mRNAs), long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), and microRNAs (miRNAs), with emerging insights into their biological functions. HCMV mRNAs are involved in crucial viral processes, such as viral replication, transcription, and translation regulation, as well as immune modulation and other effects on host cells. Additionally, four lncRNAs (RNA1.2, RNA2.7, RNA4.9, and RNA5.0) have been identified in HCMV, which play important roles in lytic replication like bypassing acute antiviral responses, promoting cell movement and viral spread, and maintaining HCMV latency. CircRNAs have gained attention for their important and diverse biological functions, including association with different diseases, acting as microRNA sponges, regulating parental gene expression, and serving as translation templates. Remarkably, HCMV encodes miRNAs which play critical roles in silencing human genes and other functions. This review gives an overview of human cytomegalovirus and current research on the HCMV transcriptome during lytic and latent infection.
Collapse
Affiliation(s)
- Janine Zeng
- Department of Microbiology and Molecular Genetics, New Jersey Medical School, Rutgers University, 225 Warren Street, Newark, NJ 070101, USA
| | - Di Cao
- Department of Pain Medicine, Huazhong University of Science and Technology Union Shenzhen Hospital, Shenzhen 518052, China
| | - Shaomin Yang
- Department of Pain Medicine, Huazhong University of Science and Technology Union Shenzhen Hospital, Shenzhen 518052, China
| | - Dabbu Kumar Jaijyan
- Department of Microbiology and Molecular Genetics, New Jersey Medical School, Rutgers University, 225 Warren Street, Newark, NJ 070101, USA
| | - Xiaolian Liu
- Institute of Pathogenic Organisms, Shenzhen Center for Disease Control and Prevention, Shenzhen 518055, China
| | - Songbin Wu
- Department of Pain Medicine, Huazhong University of Science and Technology Union Shenzhen Hospital, Shenzhen 518052, China
| | - Ruth Cruz-Cosme
- Department of Microbiology, Howard University College of Medicine, 520 W Street NW, Washington, DC 20059, USA
| | - Qiyi Tang
- Department of Microbiology, Howard University College of Medicine, 520 W Street NW, Washington, DC 20059, USA
| | - Hua Zhu
- Department of Microbiology and Molecular Genetics, New Jersey Medical School, Rutgers University, 225 Warren Street, Newark, NJ 070101, USA
| |
Collapse
|
22
|
Ourahmane A, Hertel L, McVoy MA. The RL13 Temperance Factor Represses Replication of the Highly Cell Culture-Adapted Towne Strain of Human Cytomegalovirus. Viruses 2023; 15:1023. [PMID: 37113003 PMCID: PMC10142520 DOI: 10.3390/v15041023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 04/06/2023] [Accepted: 04/17/2023] [Indexed: 04/29/2023] Open
Abstract
Human cytomegalovirus (CMV) has evolved to replicate while causing minimal damage, maintain life-long latency, reactivate sub-clinically, and, in spite of robust host immunity, produce and shed infectious virus in order to transmit to new hosts. The CMV temperance factor RL13 may contribute to this strategy of coexistence with the host by actively restricting viral replication and spread. Viruses with an intact RL13 gene grow slowly in cell culture, release little extracellular virus, and form small foci. By contrast, viruses carrying disruptive mutations in the RL13 gene form larger foci and release higher amounts of cell-free infectious virions. Such mutations invariably arise during cell culture passage of clinical isolates and are consistently found in highly adapted strains. The potential existence in such strains of other mutations with roles in mitigating RL13's restrictive effects, however, has not been explored. To this end, a mutation that frame shifts the RL13 gene in the highly cell culture-adapted laboratory strain Towne was repaired, and a C-terminal FLAG epitope was added. Compared to the frame-shifted parental virus, viruses encoding wild-type or FLAG-tagged wild-type RL13 produced small foci and replicated poorly. Within six to ten cell culture passages, mutations emerged in RL13 that restored replication and focus size to those of the RL13-frame-shifted parental virus, implying that none of the numerous adaptive mutations acquired by strain Towne during more than 125 cell culture passages mitigate the temperance activity of RL13. Whilst RL13-FLAG expressed by passage zero stocks was localized exclusively within the virion assembly compartment, RL13-FLAG with a E208K substitution that emerged in one lineage was mostly dispersed into the cytoplasm, suggesting that localization to the virion assembly compartment is likely required for RL13 to exert its growth-restricting activities. Changes in localization also provided a convenient way to assess the emergence of RL13 mutations during serial passage, highlighting the usefulness of RL13-FLAG Towne variants for elucidating the mechanisms underlying RL13's temperance functions.
Collapse
Affiliation(s)
- Amine Ourahmane
- Department of Microbiology & Immunology, Virginia Commonwealth University, Richmond, VA 23298, USA;
| | - Laura Hertel
- Department of Pediatrics, University of California San Francisco, Oakland, CA 94609, USA;
| | - Michael A. McVoy
- Department of Pediatrics, Virginia Commonwealth University, Richmond, VA 23298, USA
| |
Collapse
|
23
|
Lista MJ, Witney AA, Nichols J, Davison AJ, Wilson H, Latham KA, Ravenhill BJ, Nightingale K, Stanton RJ, Weekes MP, Neil SJD, Swanson CM, Strang BL. Strain-Dependent Restriction of Human Cytomegalovirus by Zinc Finger Antiviral Proteins. J Virol 2023; 97:e0184622. [PMID: 36916924 PMCID: PMC10062169 DOI: 10.1128/jvi.01846-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 02/16/2023] [Indexed: 03/15/2023] Open
Abstract
Cellular antiviral factors that recognize viral nucleic acid can inhibit virus replication. These include the zinc finger antiviral protein (ZAP), which recognizes high CpG dinucleotide content in viral RNA. Here, we investigated the ability of ZAP to inhibit the replication of human cytomegalovirus (HCMV). Depletion of ZAP or its cofactor KHNYN increased the titer of the high-passage HCMV strain AD169 but had little effect on the titer of the low-passage strain Merlin. We found no obvious difference in expression of several viral proteins between AD169 and Merlin in ZAP knockdown cells, but observed a larger increase in infectious virus in AD169 compared to Merlin in the absence of ZAP, suggesting that ZAP inhibited events late in AD169 replication. In addition, there was no clear difference in the CpG abundance of AD169 and Merlin RNAs, indicating that genomic content of the two virus strains was unlikely to be responsible for differences in their sensitivity to ZAP. Instead, we observed less ZAP expression in Merlin-infected cells late in replication compared to AD169-infected cells, which may be related to different abilities of the two virus strains to regulate interferon signaling. Therefore, there are strain-dependent differences in the sensitivity of HCMV to ZAP, and the ability of low-passage HCMV strain Merlin to evade inhibition by ZAP is likely related to its ability to regulate interferon signaling, not the CpG content of RNAs produced from its genome. IMPORTANCE Determining the function of cellular antiviral factors can inform our understanding of virus replication. The zinc finger antiviral protein (ZAP) can inhibit the replication of diverse viruses. Here, we examined ZAP interaction with the DNA virus human cytomegalovirus (HCMV). We found HCMV strain-dependent differences in the ability of ZAP to influence HCMV replication, which may be related to the interaction of HCMV strains with the type I interferon system. These observations affect our current understanding of how ZAP restricts HCMV and how HCMV interacts with the type I interferon system.
Collapse
Affiliation(s)
- Maria Jose Lista
- Department of Infectious Diseases, School of Immunology & Microbial Sciences, King's College London, London, United Kingdom
| | - Adam A. Witney
- Institute of Infection & Immunity, St George’s, University of London, London, United Kingdom
| | - Jenna Nichols
- MRC–University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Andrew J. Davison
- MRC–University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Harry Wilson
- Department of Infectious Diseases, School of Immunology & Microbial Sciences, King's College London, London, United Kingdom
| | - Katie A. Latham
- Institute of Infection & Immunity, St George’s, University of London, London, United Kingdom
| | - Benjamin J. Ravenhill
- Cambridge Institute for Medical Research, School of Clinical Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Katie Nightingale
- Cambridge Institute for Medical Research, School of Clinical Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Richard J. Stanton
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Michael P. Weekes
- Cambridge Institute for Medical Research, School of Clinical Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Stuart J. D. Neil
- Department of Infectious Diseases, School of Immunology & Microbial Sciences, King's College London, London, United Kingdom
| | - Chad M. Swanson
- Department of Infectious Diseases, School of Immunology & Microbial Sciences, King's College London, London, United Kingdom
| | - Blair L. Strang
- Institute of Infection & Immunity, St George’s, University of London, London, United Kingdom
| |
Collapse
|
24
|
Control of human cytomegalovirus replication by liver resident natural killer cells. Nat Commun 2023; 14:1409. [PMID: 36918610 PMCID: PMC10014884 DOI: 10.1038/s41467-023-37181-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 03/06/2023] [Indexed: 03/15/2023] Open
Abstract
Natural killer cells are considered to be important for control of human cytomegalovirus- a major pathogen in immune suppressed transplant patients. Viral infection promotes the development of an adaptive phenotype in circulating natural killer cells that changes their anti-viral function. In contrast, less is understood how natural killer cells that reside in tissue respond to viral infection. Here we show natural killer cells resident in the liver have an altered phenotype in cytomegalovirus infected individuals and display increased anti-viral activity against multiple viruses in vitro and identify and characterise a subset of natural killer cells responsible for control. Crucially, livers containing natural killer cells with better capacity to control cytomegalovirus replication in vitro are less likely to experience viraemia post-transplant. Taken together, these data suggest that virally induced expansion of tissue resident natural killer cells in the donor organ can reduce the chance of viraemia post-transplant.
Collapse
|
25
|
Gomes AC, Baraniak IA, Lankina A, Moulder Z, Holenya P, Atkinson C, Tang G, Mahungu T, Kern F, Griffiths PD, Reeves MB. The cytomegalovirus gB/MF59 vaccine candidate induces antibodies against an antigenic domain controlling cell-to-cell spread. Nat Commun 2023; 14:1041. [PMID: 36823200 PMCID: PMC9950427 DOI: 10.1038/s41467-023-36683-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 02/13/2023] [Indexed: 02/25/2023] Open
Abstract
Vaccination against human cytomegalovirus (CMV) infection remains high priority. A recombinant form of a protein essential for CMV entry, glycoprotein B (gB), demonstrated partial protection in a clinical trial (NCT00299260) when delivered with the MF59 adjuvant. Although the antibody titre against gB correlated with protection poor neutralising responses against the 5 known antigenic domains (AD) of gB were evident. Here, we show that vaccination of CMV seronegative patients induces an antibody response against a region of gB we term AD-6. Responses to the polypeptide AD-6 are detected in >70% of vaccine recipients yet in <5% of naturally infected people. An AD-6 antibody binds to gB and to infected cells but not the virion directly. Consistent with this, the AD-6 antibody is non-neutralising but, instead, prevents cell-cell spread of CMV in vitro. The discovery of AD-6 responses has the potential to explain part of the protection mediated by gB vaccines against CMV following transplantation.
Collapse
Affiliation(s)
- A C Gomes
- Institute of Immunity & Transplantation, UCL, London, NW3 2PP, United Kingdom
| | - I A Baraniak
- Institute of Immunity & Transplantation, UCL, London, NW3 2PP, United Kingdom
| | - A Lankina
- Institute of Immunity & Transplantation, UCL, London, NW3 2PP, United Kingdom
| | - Z Moulder
- Institute of Immunity & Transplantation, UCL, London, NW3 2PP, United Kingdom
| | - P Holenya
- JPT Peptide Technologies GmbH, Berlin, Germany
| | - C Atkinson
- Institute of Immunity & Transplantation, UCL, London, NW3 2PP, United Kingdom
| | - G Tang
- Institute of Immunity & Transplantation, UCL, London, NW3 2PP, United Kingdom
| | - T Mahungu
- Institute of Immunity & Transplantation, UCL, London, NW3 2PP, United Kingdom
| | - F Kern
- JPT Peptide Technologies GmbH, Berlin, Germany
- Experimental Medicine, Brighton and Sussex Medical School, Brighton, United Kingdom
| | - P D Griffiths
- Institute of Immunity & Transplantation, UCL, London, NW3 2PP, United Kingdom
| | - M B Reeves
- Institute of Immunity & Transplantation, UCL, London, NW3 2PP, United Kingdom.
| |
Collapse
|
26
|
Ashley CL, McSharry BP, McWilliam HEG, Stanton RJ, Fielding CA, Mathias RA, Fairlie DP, McCluskey J, Villadangos JA, Rossjohn J, Abendroth A, Slobedman B. Suppression of MR1 by human cytomegalovirus inhibits MAIT cell activation. Front Immunol 2023; 14:1107497. [PMID: 36845106 PMCID: PMC9950634 DOI: 10.3389/fimmu.2023.1107497] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 01/25/2023] [Indexed: 02/12/2023] Open
Abstract
Introduction The antigen presentation molecule MHC class I related protein-1 (MR1) is best characterized by its ability to present bacterially derived metabolites of vitamin B2 biosynthesis to mucosal-associated invariant T-cells (MAIT cells). Methods Through in vitro human cytomegalovirus (HCMV) infection in the presence of MR1 ligand we investigate the modulation of MR1 expression. Using coimmunoprecipitation, mass spectrometry, expression by recombinant adenovirus and HCMV deletion mutants we investigate HCMV gpUS9 and its family members as potential regulators of MR1 expression. The functional consequences of MR1 modulation by HCMV infection are explored in coculture activation assays with either Jurkat cells engineered to express the MAIT cell TCR or primary MAIT cells. MR1 dependence in these activation assays is established by addition of MR1 neutralizing antibody and CRISPR/Cas-9 mediated MR1 knockout. Results Here we demonstrate that HCMV infection efficiently suppresses MR1 surface expression and reduces total MR1 protein levels. Expression of the viral glycoprotein gpUS9 in isolation could reduce both cell surface and total MR1 levels, with analysis of a specific US9 HCMV deletion mutant suggesting that the virus can target MR1 using multiple mechanisms. Functional assays with primary MAIT cells demonstrated the ability of HCMV infection to inhibit bacterially driven, MR1-dependent activation using both neutralizing antibodies and engineered MR1 knockout cells. Discussion This study identifies a strategy encoded by HCMV to disrupt the MR1:MAIT cell axis. This immune axis is less well characterized in the context of viral infection. HCMV encodes hundreds of proteins, some of which regulate the expression of antigen presentation molecules. However the ability of this virus to regulate the MR1:MAIT TCR axis has not been studied in detail.
Collapse
Affiliation(s)
- Caroline L. Ashley
- Infection, Immunity and Inflammation, School of Medical Sciences, Faculty of Medicine and Health, and the Charles Perkins Centre, The University of Sydney, Sydney, NSW, Australia
| | - Brian P. McSharry
- Infection, Immunity and Inflammation, School of Medical Sciences, Faculty of Medicine and Health, and the Charles Perkins Centre, The University of Sydney, Sydney, NSW, Australia
- School of Dentistry and Medical Sciences, Faculty of Science and Health, Charles Sturt University, Wagga Wagga, NSW, Australia
| | - Hamish E. G. McWilliam
- Department of Microbiology and Immunology, The Peter Doherty Institute of Infection and Immunity, The University of Melbourne, Melbourne, VIC, Australia
- Department of Biochemistry and Pharmacology, Institute of Molecular Science and Biotechnology (Bio21), The University of Melbourne, Melbourne, VIC, Australia
| | - Richard J. Stanton
- Division of Infection & Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Ceri A. Fielding
- Division of Infection & Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Rommel A. Mathias
- Infection and Immunity Program, Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
| | - David P. Fairlie
- ARC Centre of Excellence for Innovations in Peptide and Protein Science, Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, Australia
| | - James McCluskey
- Department of Microbiology and Immunology, The Peter Doherty Institute of Infection and Immunity, The University of Melbourne, Melbourne, VIC, Australia
| | - Jose A. Villadangos
- Department of Microbiology and Immunology, The Peter Doherty Institute of Infection and Immunity, The University of Melbourne, Melbourne, VIC, Australia
- Department of Biochemistry and Pharmacology, Institute of Molecular Science and Biotechnology (Bio21), The University of Melbourne, Melbourne, VIC, Australia
| | - Jamie Rossjohn
- Division of Infection & Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
| | - Allison Abendroth
- Infection, Immunity and Inflammation, School of Medical Sciences, Faculty of Medicine and Health, and the Charles Perkins Centre, The University of Sydney, Sydney, NSW, Australia
| | - Barry Slobedman
- Infection, Immunity and Inflammation, School of Medical Sciences, Faculty of Medicine and Health, and the Charles Perkins Centre, The University of Sydney, Sydney, NSW, Australia
| |
Collapse
|
27
|
Vezzani G, Pimazzoni S, Ferranti R, Calò S, Monda G, Amendola D, Frigimelica E, Maione D, Cortese M, Merola M. Human immunoglobulins are transported to HCMV viral envelope by viral Fc gamma receptors-dependent and independent mechanisms. Front Microbiol 2023; 13:1106401. [PMID: 36726564 PMCID: PMC9885202 DOI: 10.3389/fmicb.2022.1106401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 12/20/2022] [Indexed: 01/18/2023] Open
Abstract
Human cytomegaloviruses (HCMVs) employ many different mechanisms to escape and subvert the host immune system, including expression of the viral IgG Fcγ receptors (vFcγRs) RL11 (gp34), RL12 (gp95), RL13 (gpRL13), and UL119 (gp68) gene products. The role of vFcγRs in HCMV pathogenesis has been reported to operate in infected cells by interfering with IgG-mediated effector functions. We found that gp34 and gp68 are envelope proteins that bind and internalize human IgGs on the surface of infected cells. Internalized IgGs are then transported on the envelope of viral particles in a vFcR-dependent mechanism. This mechanism is also responsible for the incorporation on the virions of the anti-gH neutralizing antibody MSL-109. Intriguingly, we show that gp68 is responsible for MSL-109 incorporation, but it is dispensable for other anti-HCMV antibodies that do not need this function to be transported on mature virions. HCMV-infected cells grown in presence of anti-HCMV monoclonal antibodies generate a viral progeny still infective and possible to be neutralized. This is the first example of a virus carrying neutralizing IgGs on its surface and their possible role is discussed.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Mirko Cortese
- GSK, Siena, Italy,Department of Environmental Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Caserta, Italy,Mirko Cortese, ✉
| | - Marcello Merola
- GSK, Siena, Italy,Department of Biology, University of Naples Federico II, Naples, Italy,*Correspondence: Marcello Merola, ✉
| |
Collapse
|
28
|
Human Cytomegalovirus pUL11, a CD45 Ligand, Disrupts CD4 T Cell Control of Viral Spread in Epithelial Cells. mBio 2022; 13:e0294622. [PMID: 36445084 PMCID: PMC9765415 DOI: 10.1128/mbio.02946-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Human cytomegalovirus (HCMV) encodes numerous immunomodulatory genes that facilitate its persistence. Previously described mechanisms by which HCMV avoids T cell control typically involve evasion of detection by infected cells. Here, we show that the virus also inhibits T cells directly via an interaction between the pUL11 glycoprotein on infected cells and the CD45 phosphatase on T cells. The antiviral functions of CD4 T cells are impaired as a result of this interaction, largely via induced interleukin 10 (IL-10) secretion in the CD4 T cell central memory compartment, resulting in enhanced viral spread. This establishes CD45 as an inhibitory receptor that regulates antiviral T cell functions and has parallels with the manipulation of natural killer (NK) cells by HCMV. By coculturing donor T cells with HCMV-infected epithelial cells, we observed that CD4 T cells can respond to epithelial cell antigen presentation and can control HCMV spread via cytolytic and cytokine-dependent mechanisms. pUL11 impairs both mechanisms. We showed that pUL11-induced IL-10 secretion requires IL-2, mTOR, and T cell receptor signaling. This characterization of the effects of the pUL11-CD45 interaction may allow for the development of new antiviral therapies and treatments for inflammatory disorders. IMPORTANCE Human cytomegalovirus (HCMV) is adept at avoiding its host's immune defenses, both by evading detection and by directly inhibiting immune cells. This can lead to a loss of control of the infection, and dangerous disease can result, particularly in cases in which an individual's immune system is immature, weak, or suppressed. T cells form a crucial part of the response to HCMV and are used in cellular HCMV therapies. We show that an interaction between a viral glycoprotein (pUL11) and a T cell surface receptor (CD45) impairs T cell memory functions and allows for increased viral spread. This defines a new immunomodulatory strategy for the virus as well as a new T cell regulatory mechanism. These results are important, as they increase our understanding of how T cells function and how HCMV disrupts them. This will allow for the development of new antiviral therapies that restore T cell functions and indicates a new target for controlling pathological T cell disorders.
Collapse
|
29
|
Turner DL, Mathias RA. The human cytomegalovirus decathlon: Ten critical replication events provide opportunities for restriction. Front Cell Dev Biol 2022; 10:1053139. [PMID: 36506089 PMCID: PMC9732275 DOI: 10.3389/fcell.2022.1053139] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Accepted: 11/10/2022] [Indexed: 11/27/2022] Open
Abstract
Human cytomegalovirus (HCMV) is a ubiquitous human pathogen that can cause severe disease in immunocompromised individuals, transplant recipients, and to the developing foetus during pregnancy. There is no protective vaccine currently available, and with only a limited number of antiviral drug options, resistant strains are constantly emerging. Successful completion of HCMV replication is an elegant feat from a molecular perspective, with both host and viral processes required at various stages. Remarkably, HCMV and other herpesviruses have protracted replication cycles, large genomes, complex virion structure and complicated nuclear and cytoplasmic replication events. In this review, we outline the 10 essential stages the virus must navigate to successfully complete replication. As each individual event along the replication continuum poses as a potential barrier for restriction, these essential checkpoints represent potential targets for antiviral development.
Collapse
Affiliation(s)
- Declan L. Turner
- Department of Microbiology, Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
| | - Rommel A. Mathias
- Department of Microbiology, Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Melbourne, VIC, Australia
| |
Collapse
|
30
|
Turner DL, Fritzlar S, Sadeghipour S, Barugahare AA, Russ BE, Turner SJ, Mathias RA. UL49 is an essential subunit of the viral pre-initiation complex that regulates human cytomegalovirus gene transcription. iScience 2022; 25:105168. [PMID: 36204275 PMCID: PMC9530030 DOI: 10.1016/j.isci.2022.105168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 07/25/2022] [Accepted: 09/16/2022] [Indexed: 11/03/2022] Open
Abstract
More than half the world’s population is infected with human cytomegalovirus (HCMV), causing congenital birth defects and impacting the immuno-compromised. Many of the >170 HCMV genes remain uncharacterized, and this gap in knowledge limits the development of novel antivirals. In this study, we investigated the essential viral protein UL49 and found it displayed leaky late expression kinetics, and localized to nuclear replication compartments. Cells infected with mutant UL49 virus were unable to produce infectious virions and phenocopied other beta-gamma viral pre-initiation complex (vPIC) subunit (UL79, UL87, UL91, UL92, and UL95) mutant infections. RNA-seq analysis of vPIC mutant infections revealed a consistent diminution of genes encoding capsid subunits, including TRX2/UL85 and MCP/UL86, envelope glycoproteins gM, gL and gO, and egress-associated tegument proteins UL99 and UL103. Therefore, as a member of the vPIC, UL49 serves as a fundamental HCMV effector that governs viral gene transcription required to complete the replication cycle. Beta- and gamma-herpes viruses encode a viral pre-initiation complex (vPIC) UL49, together with UL79, UL87, UL91, UL92, and UL95 Comprise the HCMV vPIC UL49 is essential for HCMV replication and orchestrates late viral gene expression Mutation of vPIC subunits reduces the transcription of structural virion components
Collapse
|
31
|
Strang BL. Toward inhibition of human cytomegalovirus replication with compounds targeting cellular proteins. J Gen Virol 2022; 103. [PMID: 36215160 DOI: 10.1099/jgv.0.001795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Antiviral therapy for human cytomegalovirus (HCMV) currently relies upon direct-acting antiviral drugs. However, it is now well known that these drugs have shortcomings, which limit their use. Here I review the identification and investigation of compounds targeting cellular proteins that have anti-HCMV activity and could supersede those anti-HCMV drugs currently in use. This includes discussion of drug repurposing, for example the use of artemisinin compounds, and discussion of new directions to identify compounds that target cellular factors in HCMV-infected cells, for example screening of kinase inhibitors. In addition, I highlight developing areas such as the use of machine learning and emphasize how interaction with fields outside virology will be critical for development of anti-HCMV compounds.
Collapse
Affiliation(s)
- Blair L Strang
- Institute for Infection & Immunity, St George's, University of London, London, UK
| |
Collapse
|
32
|
Malouli D, Gilbride RM, Wu HL, Hwang JM, Maier N, Hughes CM, Newhouse D, Morrow D, Ventura AB, Law L, Tisoncik-Go J, Whitmore L, Smith E, Golez I, Chang J, Reed JS, Waytashek C, Weber W, Taher H, Uebelhoer LS, Womack JL, McArdle MR, Gao J, Papen CR, Lifson JD, Burwitz BJ, Axthelm MK, Smedley J, Früh K, Gale M, Picker LJ, Hansen SG, Sacha JB. Cytomegalovirus-vaccine-induced unconventional T cell priming and control of SIV replication is conserved between primate species. Cell Host Microbe 2022; 30:1207-1218.e7. [PMID: 35981532 PMCID: PMC9927879 DOI: 10.1016/j.chom.2022.07.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 06/01/2022] [Accepted: 07/19/2022] [Indexed: 01/26/2023]
Abstract
Strain 68-1 rhesus cytomegalovirus expressing simian immunodeficiency virus (SIV) antigens (RhCMV/SIV) primes MHC-E-restricted CD8+ T cells that control SIV replication in 50%-60% of the vaccinated rhesus macaques. Whether this unconventional SIV-specific immunity and protection is unique to rhesus macaques or RhCMV or is intrinsic to CMV remains unknown. Here, using cynomolgus CMV vectors expressing SIV antigens (CyCMV/SIV) and Mauritian cynomolgus macaques, we demonstrate that the induction of MHC-E-restricted CD8+ T cells requires matching CMV to its host species. RhCMV does not elicit MHC-E-restricted CD8+ T cells in cynomolgus macaques. However, cynomolgus macaques vaccinated with species-matched 68-1-like CyCMV/SIV mounted MHC-E-restricted CD8+ T cells, and half of the vaccinees stringently controlled SIV post-challenge. Protected animals manifested a vaccine-induced IL-15 transcriptomic signature that is associated with efficacy in rhesus macaques. These findings demonstrate that the ability of species-matched CMV vectors to elicit MHC-E-restricted CD8+ T cells that are required for anti-SIV efficacy is conserved in nonhuman primates, and these data support the development of HCMV/HIV for a prophylactic HIV vaccine.
Collapse
Affiliation(s)
- Daniel Malouli
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Roxanne M Gilbride
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Helen L Wu
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Joseph M Hwang
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Nicholas Maier
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Colette M Hughes
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Daniel Newhouse
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, WA 98109, USA
| | - David Morrow
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Abigail B Ventura
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Lynn Law
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, WA 98109, USA
| | - Jennifer Tisoncik-Go
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, WA 98109, USA
| | - Leanne Whitmore
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, WA 98109, USA
| | - Elise Smith
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, WA 98109, USA
| | - Inah Golez
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, WA 98109, USA
| | - Jean Chang
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, WA 98109, USA
| | - Jason S Reed
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Courtney Waytashek
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Whitney Weber
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Husam Taher
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Luke S Uebelhoer
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Jennie L Womack
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Matthew R McArdle
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Junwei Gao
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Courtney R Papen
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Jeffrey D Lifson
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21701, USA
| | - Benjamin J Burwitz
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Michael K Axthelm
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Jeremy Smedley
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Klaus Früh
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Michael Gale
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, WA 98109, USA
| | - Louis J Picker
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Scott G Hansen
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA.
| | - Jonah B Sacha
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR 97006, USA; Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, 97006, USA.
| |
Collapse
|
33
|
Clement M, Forbester JL, Marsden M, Sabberwal P, Sommerville MS, Wellington D, Dimonte S, Clare S, Harcourt K, Yin Z, Nobre L, Antrobus R, Jin B, Chen M, Makvandi-Nejad S, Lindborg JA, Strittmatter SM, Weekes MP, Stanton RJ, Dong T, Humphreys IR. IFITM3 restricts virus-induced inflammatory cytokine production by limiting Nogo-B mediated TLR responses. Nat Commun 2022; 13:5294. [PMID: 36075894 PMCID: PMC9454482 DOI: 10.1038/s41467-022-32587-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 08/08/2022] [Indexed: 11/20/2022] Open
Abstract
Interferon-induced transmembrane protein 3 (IFITM3) is a restriction factor that limits viral pathogenesis and exerts poorly understood immunoregulatory functions. Here, using human and mouse models, we demonstrate that IFITM3 promotes MyD88-dependent, TLR-mediated IL-6 production following exposure to cytomegalovirus (CMV). IFITM3 also restricts IL-6 production in response to influenza and SARS-CoV-2. In dendritic cells, IFITM3 binds to the reticulon 4 isoform Nogo-B and promotes its proteasomal degradation. We reveal that Nogo-B mediates TLR-dependent pro-inflammatory cytokine production and promotes viral pathogenesis in vivo, and in the case of TLR2 responses, this process involves alteration of TLR2 cellular localization. Nogo-B deletion abrogates inflammatory cytokine responses and associated disease in virus-infected IFITM3-deficient mice. Thus, we uncover Nogo-B as a driver of viral pathogenesis and highlight an immunoregulatory pathway in which IFITM3 fine-tunes the responsiveness of myeloid cells to viral stimulation.
Collapse
Affiliation(s)
- M Clement
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, CF14 4XN, UK
| | - J L Forbester
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, CF14 4XN, UK
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, Oxford University, Oxford, OX3 9DS, UK
| | - M Marsden
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, CF14 4XN, UK
| | - P Sabberwal
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, CF14 4XN, UK
| | - M S Sommerville
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, CF14 4XN, UK
| | - D Wellington
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, Oxford University, Oxford, OX3 9DS, UK
- Chinese Academy of Medical Sciences (CAMS) Oxford Institute (COI), University of Oxford, Oxford, UK
| | - S Dimonte
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, CF14 4XN, UK
| | - S Clare
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, UK
| | - K Harcourt
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, UK
| | - Z Yin
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, Oxford University, Oxford, OX3 9DS, UK
- Chinese Academy of Medical Sciences (CAMS) Oxford Institute (COI), University of Oxford, Oxford, UK
| | - L Nobre
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge, CB2 0XY, UK
| | - R Antrobus
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge, CB2 0XY, UK
| | - B Jin
- Fourth Military Medical University, Xian, China
| | - M Chen
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, 06536, USA
| | - S Makvandi-Nejad
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, Oxford University, Oxford, OX3 9DS, UK
| | - J A Lindborg
- Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - S M Strittmatter
- Departments of Neurology and Neuroscience, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - M P Weekes
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge, CB2 0XY, UK
| | - R J Stanton
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, CF14 4XN, UK
| | - T Dong
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, Oxford University, Oxford, OX3 9DS, UK
- Chinese Academy of Medical Sciences (CAMS) Oxford Institute (COI), University of Oxford, Oxford, UK
| | - I R Humphreys
- Division of Infection and Immunity/Systems Immunity University Research Institute, Cardiff University, Cardiff, CF14 4XN, UK.
| |
Collapse
|
34
|
Statkute E, Wang ECY, Stanton RJ. An Optimized CRISPR/Cas9 Adenovirus Vector (AdZ-CRISPR) for High-Throughput Cloning of sgRNA, Using Enhanced sgRNA and Cas9 Variants. Hum Gene Ther 2022; 33:990-1001. [PMID: 35196879 DOI: 10.1089/hum.2021.120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Recombinant adenovirus vectors enable highly efficient gene delivery in vitro and in vivo. As a result, they are widely used in gene therapy, vaccination, and anticancer applications. We have previously developed the AdZ vector system, which uses recombineering to permit high-throughput cloning of transgenes into Adenovirus vectors, simplifies alteration of the vector backbone, and enables rapid recovery of infectious virus, even if a transgene is incompatible with vector replication. In this study, we adapt this vector system to enable high-throughput cloning of sequences for CRISPR/Cas9 editing. Vectors were optimized to ensure efficient cloning, and high editing efficiency using spCas9 and single guide RNA (sgRNA) sequences in a single vector. Using a multiplicity of infection of 50, knockout efficiencies of up to 80% could be achieved with a single sgRNA. Vectors were further enhanced by altering the spCas9 sequence to match that of SniperCas9, which has reduced off-target activity, but maintains on-target efficiency, and by applying modifications to the sgRNA sequence that significantly enhance editing efficiency. Thus, the AdZ-CRISPR vectors offer highly efficient knockout, even in hard to transfect cells, and enables large-scale CRISPR/Cas9 projects to be undertaken easily and quickly.
Collapse
Affiliation(s)
- Evelina Statkute
- Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Eddie C Y Wang
- Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Richard J Stanton
- Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| |
Collapse
|
35
|
Flomm FJ, Soh TK, Schneider C, Wedemann L, Britt HM, Thalassinos K, Pfitzner S, Reimer R, Grünewald K, Bosse JB. Intermittent bulk release of human cytomegalovirus. PLoS Pathog 2022; 18:e1010575. [PMID: 35925870 PMCID: PMC9352052 DOI: 10.1371/journal.ppat.1010575] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 05/06/2022] [Indexed: 01/24/2023] Open
Abstract
Human Cytomegalovirus (HCMV) can infect a variety of cell types by using virions of varying glycoprotein compositions. It is still unclear how this diversity is generated, but spatio-temporally separated envelopment and egress pathways might play a role. So far, one egress pathway has been described in which HCMV particles are individually enveloped into small vesicles and are subsequently exocytosed continuously. However, some studies have also found enveloped virus particles inside multivesicular structures but could not link them to productive egress or degradation pathways. We used a novel 3D-CLEM workflow allowing us to investigate these structures in HCMV morphogenesis and egress at high spatio-temporal resolution. We found that multiple envelopment events occurred at individual vesicles leading to multiviral bodies (MViBs), which subsequently traversed the cytoplasm to release virions as intermittent bulk pulses at the plasma membrane to form extracellular virus accumulations (EVAs). Our data support the existence of a novel bona fide HCMV egress pathway, which opens the gate to evaluate divergent egress pathways in generating virion diversity.
Collapse
Affiliation(s)
- Felix J. Flomm
- Centre for Structural Systems Biology, Hamburg, Germany
- Hannover Medical School, Institute of Virology, Hannover, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
- Leibniz-Institute of Virology (LIV), Hamburg, Germany
| | - Timothy K. Soh
- Centre for Structural Systems Biology, Hamburg, Germany
- Hannover Medical School, Institute of Virology, Hannover, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
- Leibniz-Institute of Virology (LIV), Hamburg, Germany
| | | | - Linda Wedemann
- Centre for Structural Systems Biology, Hamburg, Germany
- Hannover Medical School, Institute of Virology, Hannover, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
- Leibniz-Institute of Virology (LIV), Hamburg, Germany
| | - Hannah M. Britt
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London, United Kingdom
| | - Konstantinos Thalassinos
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London, United Kingdom
- Institute of Structural and Molecular Biology, Birkbeck College, University of London, London, United Kingdom
| | | | | | - Kay Grünewald
- Centre for Structural Systems Biology, Hamburg, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
- Leibniz-Institute of Virology (LIV), Hamburg, Germany
- University of Hamburg, Department of Chemistry, Hamburg, Germany
| | - Jens B. Bosse
- Centre for Structural Systems Biology, Hamburg, Germany
- Hannover Medical School, Institute of Virology, Hannover, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
- Leibniz-Institute of Virology (LIV), Hamburg, Germany
| |
Collapse
|
36
|
Braun B, Laib Sampaio K, Kuderna AK, Widmann M, Sinzger C. Viral and Cellular Factors Contributing to the Hematogenous Dissemination of Human Cytomegalovirus via Polymorphonuclear Leukocytes. Viruses 2022; 14:v14071561. [PMID: 35891541 PMCID: PMC9323586 DOI: 10.3390/v14071561] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 07/12/2022] [Accepted: 07/16/2022] [Indexed: 02/06/2023] Open
Abstract
Polymorphonuclear leukocytes (PMNs) presumably transmit human cytomegalovirus (HCMV) between endothelial cells in blood vessels and thereby facilitate spread to peripheral organs. We aimed to identify viral components that contribute to PMN-mediated transmission and test the hypothesis that cellular adhesion molecules shield transmission sites from entry inhibitors. Stop codons were introduced into the genome of HCMV strain Merlin to delete pUL74 of the trimeric and pUL128 of the pentameric glycoprotein complex and the tegument proteins pp65 and pp71. Mutants were analyzed regarding virus uptake by PMNs and transfer of infection to endothelial cells. Cellular adhesion molecules were evaluated for their contribution to virus transmission using function-blocking antibodies, and hits were further analyzed regarding shielding against inhibitors of virus entry. The viral proteins pUL128, pp65, and pp71 were required for efficient PMN-mediated transmission, whereas pUL74 was dispensable. On the cellular side, the blocking of the αLβ2-integrin LFA-1 reduced virus transfer by 50% and allowed entry inhibitors to reduce it further by 30%. In conclusion, these data show that PMN-mediated transmission depends on the pentameric complex and an intact tegument and supports the idea of a virological synapse that promotes this dissemination mode both directly and via immune evasion.
Collapse
|
37
|
Combined knockdown of RL13 and UL128 for release of cell-free infectivity from recent HCMV isolates. J Virol Methods 2022; 305:114537. [PMID: 35526667 DOI: 10.1016/j.jviromet.2022.114537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 04/28/2022] [Indexed: 11/23/2022]
Abstract
Due to strictly cell-associated growth, experiments requiring cell-free virus are not applicable to recent clinical HCMV isolates to date. On the other hand, adaptation to cell-free growth is associated with undesirable changes in the viral gene regions RL13 and UL128. We had previously found that siRNA-mediated reduction of UL128 expression allowed transient release of cell-free virus by clinical isolates, and now hypothesized that virus yield could be further increased by additional knockdown of RL13. Despite the extensive polymorphism of RL13, effective RL13-specific siRNAs could be designed for three recent isolates and the Merlin strain. Knockdown efficiency was demonstrated at the protein level with a Merlin variant expressing V5-tagged pRL13. Knockdown of RL13 alone did not result in measurable release of cell-free virus, but combined knockdown of RL13 and UL128 increased infectivity in cell-free supernatants by a factor of 10-2000 compared to knockdown of UL128 alone. These supernatants could be used in dose-response assays to compare the effect of a neutralizing antibody on the various HCMV isolates. In summary, combined knockdown of RL13 and UL128 by specific siRNAs allows reliable release of cell-free infectivity from otherwise strictly cell-associated HCMV isolates without the need to modify the viral genome.
Collapse
|
38
|
Li J, Wellnitz S, Chi XS, Yue Y, Schmidt KA, Nguyen N, Chen W, Yurgelonis I, Rojas E, Liu Y, Loschko J, Pollozi E, Matsuka YV, Needle E, Vidunas E, Donald RGK, Moran J, Jansen KU, Dormitzer PR, Barry PA, Yang X. Horizontal transmission of cytomegalovirus in a rhesus model despite high-level, vaccine-elicited neutralizing antibody and T cell responses. J Infect Dis 2022; 226:585-594. [PMID: 35413121 PMCID: PMC10147388 DOI: 10.1093/infdis/jiac129] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 04/07/2022] [Indexed: 11/14/2022] Open
Abstract
The development of a vaccine to prevent congenital human cytomegalovirus (HCMV) disease is a public health priority. We tested rhesus CMV (RhCMV) prototypes of HCMV vaccine candidates in a seronegative macaque oral challenge model. Immunogens included a recombinant pentameric complex (PC; gH/gL/pUL128/pUL130/pUL131A), a postfusion gB ectodomain, and a DNA plasmid that encodes pp65-2. Immunization with QS21-adjuvanted PC alone or with the other immunogens elicited neutralizing titers comparable to those elicited by RhCMV infection. Similarly, immunization with all three immunogens elicited pp65-specific cytotoxic T cell responses comparable to those elicited by RhCMV infection. RhCMV readily infected immunized animals and was detected in saliva, blood and urine after challenge in quantities similar to those in placebo-immunized animals. If HCMV evades vaccine-elicited immunity in humans as RhCMV evaded immunity in macaques, a HCMV vaccine must elicit immunity superior to, or different from, that elicited by the prototype RhCMV vaccine to block horizontal transmission.
Collapse
Affiliation(s)
- Julia Li
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Sabine Wellnitz
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Xiaoyuan S Chi
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Yujuan Yue
- Center for Comparative Medicine, University of California, Davis, Davis, CA 95616, USA
| | - Kimberli A Schmidt
- Center for Comparative Medicine, University of California, Davis, Davis, CA 95616, USA
| | - Nancy Nguyen
- Center for Comparative Medicine, University of California, Davis, Davis, CA 95616, USA
| | - Wei Chen
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Irina Yurgelonis
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Eduardo Rojas
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Yuhang Liu
- Groton Center for Chemistry, Pfizer Inc., Groton, CT 06340, USA
| | - Jakob Loschko
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Eneida Pollozi
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Yury V Matsuka
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Elie Needle
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Eugene Vidunas
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Robert G K Donald
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Justin Moran
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Kathrin U Jansen
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Philip R Dormitzer
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| | - Peter A Barry
- Center for Comparative Medicine, University of California, Davis, Davis, CA 95616, USA.,Department of Pathology and Laboratory Medicine, University of California, Davis, Davis, CA 95616, USA.,California National Primate Research Center, University of California, Davis, Davis, CA 95616, USA
| | - Xinzhen Yang
- Vaccine Research and Development, Pfizer Inc., Pearl River, New York 10965, USA
| |
Collapse
|
39
|
Human cytomegalovirus protein RL1 degrades the antiviral factor SLFN11 via recruitment of the CRL4 E3 ubiquitin ligase complex. Proc Natl Acad Sci U S A 2022; 119:2108173119. [PMID: 35105802 PMCID: PMC8832970 DOI: 10.1073/pnas.2108173119] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/14/2021] [Indexed: 02/08/2023] Open
Abstract
Human cytomegalovirus (HCMV) is an important human pathogen and a paradigm of viral immune evasion, targeting intrinsic, innate, and adaptive immunity. We have employed two orthogonal multiplexed tandem mass tag-based proteomic screens to identify host proteins down-regulated by viral factors expressed during the latest phases of viral infection. This approach revealed that the HIV-1 restriction factor Schlafen-11 (SLFN11) was degraded by the poorly characterized, late-expressed HCMV protein RL1, via recruitment of the Cullin4-RING E3 Ubiquitin Ligase (CRL4) complex. SLFN11 potently restricted HCMV infection, inhibiting the formation and spread of viral plaques. Overall, we show that a restriction factor previously thought only to inhibit RNA viruses additionally restricts HCMV. We define the mechanism of viral antagonism and also describe an important resource for revealing additional molecules of importance in antiviral innate immunity and viral immune evasion.
Collapse
|
40
|
Phan QV, Bogdanow B, Wyler E, Landthaler M, Liu F, Hagemeier C, Wiebusch L. Engineering, decoding and systems-level characterization of chimpanzee cytomegalovirus. PLoS Pathog 2022; 18:e1010193. [PMID: 34982803 PMCID: PMC8759705 DOI: 10.1371/journal.ppat.1010193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 01/14/2022] [Accepted: 12/09/2021] [Indexed: 11/19/2022] Open
Abstract
The chimpanzee cytomegalovirus (CCMV) is the closest relative of human CMV (HCMV). Because of the high conservation between these two species and the ability of human cells to fully support CCMV replication, CCMV holds great potential as a model system for HCMV. To make the CCMV genome available for precise and rapid gene manipulation techniques, we captured the genomic DNA of CCMV strain Heberling as a bacterial artificial chromosome (BAC). Selected BAC clones were reconstituted to infectious viruses, growing to similar high titers as parental CCMV. DNA sequencing confirmed the integrity of our clones and led to the identification of two polymorphic loci and a deletion-prone region within the CCMV genome. To re-evaluate the CCMV coding potential, we analyzed the viral transcriptome and proteome and identified several novel ORFs, splice variants, and regulatory RNAs. We further characterized the dynamics of CCMV gene expression and found that viral proteins cluster into five distinct temporal classes. In addition, our datasets revealed that the host response to CCMV infection and the de-regulation of cellular pathways are in line with known hallmarks of HCMV infection. In a first functional experiment, we investigated a proposed frameshift mutation in UL128 that was suspected to restrict CCMV's cell tropism. In fact, repair of this frameshift re-established productive CCMV infection in endothelial and epithelial cells, expanding the options of CCMV as an infection model. Thus, BAC-cloned CCMV can serve as a powerful tool for systematic approaches in comparative functional genomics, exploiting the close phylogenetic relationship between CCMV and HCMV.
Collapse
Affiliation(s)
- Quang Vinh Phan
- Department of Pediatric Oncology/Hematology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Boris Bogdanow
- Department of Structural Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Emanuel Wyler
- Berlin Institute for Medical Systems Biology, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | - Markus Landthaler
- Berlin Institute for Medical Systems Biology, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | - Fan Liu
- Department of Structural Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Christian Hagemeier
- Department of Pediatric Oncology/Hematology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Lüder Wiebusch
- Department of Pediatric Oncology/Hematology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| |
Collapse
|
41
|
Hancock TJ, Hetzel ML, Ramirez A, Sparer TE. MCMV Centrifugal Enhancement: A New Spin on an Old Topic. Pathogens 2021; 10:1577. [PMID: 34959531 PMCID: PMC8705575 DOI: 10.3390/pathogens10121577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/02/2021] [Accepted: 12/02/2021] [Indexed: 11/17/2022] Open
Abstract
Human cytomegalovirus (HCMV) is a ubiquitous pathogen infecting a majority of people worldwide, with diseases ranging from mild to life-threatening. Its clinical relevance in immunocompromised people and congenital infections have made treatment and vaccine development a top priority. Because of cytomegaloviruses' species specificity, murine cytomegalovirus (MCMV) models have historically informed and advanced translational CMV therapies. Using the phenomenon of centrifugal enhancement, we explored differences between MCMVs derived in vitro and in vivo. We found centrifugal enhancement on tissue culture-derived virus (TCV) was ~3× greater compared with salivary gland derived virus (SGV). Using novel "flow virometry", we found that TCV contained a distinct submicron particle composition compared to SGV. Using an inhibitor of exosome production, we show these submicron particles are not extracellular vesicles that contribute to centrifugal enhancement. We examined how these differences in submicron particles potentially contribute to differing centrifugal enhancement phenotypes, as well as broader in vivo vs. in vitro MCMV differences.
Collapse
Affiliation(s)
| | | | | | - Tim E. Sparer
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA; (T.J.H.); (M.L.H.); (A.R.)
| |
Collapse
|
42
|
Hyde K, Sultana N, Tran AC, Bileckaja N, Donald CL, Kohl A, Stanton RJ, Strang BL. Limited replication of human cytomegalovirus in a trophoblast cell line. J Gen Virol 2021; 102. [PMID: 34816792 PMCID: PMC8742992 DOI: 10.1099/jgv.0.001683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Several viruses, including human cytomegalovirus (HCMV), are thought to replicate in the placenta. However, there is little understanding of the molecular mechanisms involved in HCMV replication in this tissue. We investigated replication of HCMV in the extravillous trophoblast cell line SGHPL-4, a commonly used model of HCMV replication in the placenta. We found limited HCMV protein expression and virus replication in SGHPL-4 cells. This was associated with a lack of trophoblast progenitor cell protein markers in SGHPL-4 cells, suggesting a relationship between trophoblast differentiation and limited HCMV replication. We proposed that limited HCMV replication in trophoblast cells is advantageous to vertical transmission of HCMV, as there is a greater opportunity for vertical transmission when the placenta is intact and functional. Furthermore, when we investigated the replication of other vertically transmitted viruses in SGHPL-4 cells we found some limitation to replication of Zika virus, but not herpes simplex virus. Thus, limited replication of some, but not all, vertically transmitted viruses may be a feature of trophoblast cells.
Collapse
Affiliation(s)
- Kadeem Hyde
- Institute for Infection and Immunity, St George's, University of London, London, UK
| | - Nowshin Sultana
- Institute for Infection and Immunity, St George's, University of London, London, UK
| | - Andy C Tran
- Institute for Infection and Immunity, St George's, University of London, London, UK
| | - Narina Bileckaja
- Institute for Infection and Immunity, St George's, University of London, London, UK
| | - Claire L Donald
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
| | - Alain Kohl
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
| | - Richard J Stanton
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK
| | - Blair L Strang
- Institute for Infection and Immunity, St George's, University of London, London, UK
| |
Collapse
|
43
|
Lau B, Kerr K, Camiolo S, Nightingale K, Gu Q, Antrobus R, Suárez NM, Loney C, Stanton RJ, Weekes MP, Davison AJ. Human Cytomegalovirus RNA2.7 Is Required for Upregulating Multiple Cellular Genes To Promote Cell Motility and Viral Spread Late in Lytic Infection. J Virol 2021; 95:e0069821. [PMID: 34346763 PMCID: PMC8475523 DOI: 10.1128/jvi.00698-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Accepted: 07/22/2021] [Indexed: 11/20/2022] Open
Abstract
Long noncoding RNAs (lncRNAs) are frequently associated with broad modulation of gene expression and thus provide the cell with the ability to synchronize entire metabolic processes. We used transcriptomic approaches to investigate whether the most abundant human cytomegalovirus-encoded lncRNA, RNA2.7, has this characteristic. By comparing cells infected with wild-type virus (WT) to cells infected with RNA2.7 deletion mutants, RNA2.7 was implicated in regulating a large number of cellular genes late in lytic infection. Pathway analysis indicated that >100 of these genes are associated with promoting cell movement, and the 10 most highly regulated of these were validated in further experiments. Morphological analysis and live cell tracking of WT- and RNA2.7 mutant-infected cells indicated that RNA2.7 is involved in promoting the movement and detachment of infected cells late in infection, and plaque assays using sparse cell monolayers indicated that RNA2.7 is also involved in promoting cell-to-cell spread of virus. Consistent with the observation that upregulated mRNAs are relatively A+U-rich, which is a trait associated with transcript instability, and that they are also enriched in motifs associated with mRNA instability, transcriptional inhibition experiments on WT- and RNA2.7 mutant-infected cells showed that four upregulated transcripts lived longer in the presence of RNA2.7. These findings demonstrate that RNA2.7 is required for promoting cell movement and viral spread late in infection and suggest that this may be due to general stabilization of A+U-rich transcripts. IMPORTANCE In addition to messenger RNAs (mRNAs), the human genome encodes a large number of long noncoding RNAs (lncRNAs). Many lncRNAs that have been studied in detail are associated with broad modulation of gene expression and have important biological roles. Human cytomegalovirus, which is a large, clinically important DNA virus, specifies four lncRNAs, one of which (RNA2.7) is expressed at remarkably high levels during lytic infection. Our studies show that RNA2.7 is required for upregulating a large number of human genes, about 100 of which are associated with cell movement, and for promoting the movement of infected cells and the spread of virus from one cell to another. Further bioinformatic and experimental analyses indicated that RNA2.7 may exert these effects by stabilizing mRNAs that are relatively rich in A and U nucleotides. These findings increase our knowledge of how human cytomegalovirus regulates the infected cell to promote its own success.
Collapse
Affiliation(s)
- Betty Lau
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Karen Kerr
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Salvatore Camiolo
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Katie Nightingale
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
| | - Quan Gu
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Robin Antrobus
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
| | - Nicolás M. Suárez
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Colin Loney
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Richard J. Stanton
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Michael P. Weekes
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
| | - Andrew J. Davison
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| |
Collapse
|
44
|
Peptide Derivatives of Platelet-Derived Growth Factor Receptor Alpha Inhibit Cell-Associated Spread of Human Cytomegalovirus. Viruses 2021; 13:v13091780. [PMID: 34578361 PMCID: PMC8473290 DOI: 10.3390/v13091780] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/26/2021] [Accepted: 09/01/2021] [Indexed: 12/27/2022] Open
Abstract
Cell-free human cytomegalovirus (HCMV) can be inhibited by a soluble form of the cellular HCMV-receptor PDGFRα, resembling neutralization by antibodies. The cell-associated growth of recent HCMV isolates, however, is resistant against antibodies. We investigated whether PDGFRα-derivatives can inhibit this transmission mode. A protein containing the extracellular PDGFRα-domain and 40-mer peptides derived therefrom were tested regarding the inhibition of the cell-associated HCMV strain Merlin-pAL1502, hits were validated with recent isolates, and the most effective peptide was modified to increase its potency. The modified peptide was further analyzed regarding its mode of action on the virion level. While full-length PDGFRα failed to inhibit HCMV isolates, three peptides significantly reduced virus growth. A 30-mer version of the lead peptide (GD30) proved even more effective against the cell-free virus, and this effect was HCMV-specific and depended on the viral glycoprotein O. In cell-associated spread, GD30 reduced both the number of transferred particles and their penetration. This effect was reversible after peptide removal, which allowed the synchronized analysis of particle transfer, showing that two virions per hour were transferred to neighboring cells and one virion was sufficient for infection. In conclusion, PDGFRα-derived peptides are novel inhibitors of the cell-associated spread of HCMV and facilitate the investigation of this transmission mode.
Collapse
|
45
|
Hamilton ST, Hahn F, Sonntag E, Marschall M, Rawlinson WD. A placental specific miRNA miR-517a-3p exerts anti-human cytomegalovirus activity. Placenta 2021; 112:62-65. [PMID: 34298423 DOI: 10.1016/j.placenta.2021.06.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 05/21/2021] [Accepted: 06/30/2021] [Indexed: 10/21/2022]
Abstract
Human cytomegalovirus congenital infection is the leading non-genetic cause of fetal malformation in developed countries. There are currently no safe antivirals for use during pregnancy. Placental trophoblast cells specifically secrete exosomes containing miRNA from the chromosome 19 miRNA cluster (C19MC) which confer viral resistance to recipient cells. We show the highly expressed C19MC miRNA miR-517a-3p inhibits HCMV replication and viral protein expression in both fibroblast and trophoblast cell cultures (71.6% and 50.4% inhibition of HCMV DNA at 7 days post infection respectively; p < 0.05). This naturally occurring molecule has potential for opening-up antiviral therapeutic strategies for pregnancy.
Collapse
Affiliation(s)
- Stuart T Hamilton
- Serology and Virology Division, SEALS Microbiology, Prince of Wales Hospital, Sydney, Australia; School of Women's and Children's Health, University of New South Wales, Australia
| | - Friedrich Hahn
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Germany
| | - Eric Sonntag
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Germany
| | - Manfred Marschall
- Institute for Clinical and Molecular Virology, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Germany
| | - William D Rawlinson
- Serology and Virology Division, SEALS Microbiology, Prince of Wales Hospital, Sydney, Australia; School of Women's and Children's Health, University of New South Wales, Australia; School of Medical Sciences, University of New South Wales, Australia; School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia.
| |
Collapse
|
46
|
A Novel Strain-Specific Neutralizing Epitope on Glycoprotein H of Human Cytomegalovirus. J Virol 2021; 95:e0065721. [PMID: 34160252 DOI: 10.1128/jvi.00657-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Human cytomegalovirus (HCMV) is a ubiquitous pathogen that causes severe clinical disease in immunosuppressed patients and congenitally infected newborn infants. Viral envelope glycoproteins represent attractive targets for vaccination or passive immunotherapy. To extend the knowledge of mechanisms of virus neutralization, monoclonal antibodies (MAbs) were generated following immunization of mice with HCMV virions. Hybridoma supernatants were screened for in vitro neutralization activity, yielding three potent MAbs, 6E3, 3C11, and 2B10. MAbs 6E3 and 3C11 blocked infection of all viral strains that were tested, while MAb 2B10 neutralized only 50% of the HCMV strains analyzed. Characterization of the MAbs using indirect immunofluorescence analyses demonstrated their reactivity with recombinantly derived gH. While MAbs 6E3 and 3C11 reacted with gH when expressed alone, 2B10 detected gH only when it was coexpressed with gB and gL. Recognition of gH by 3C11 was dependent on the expression of the entire ectodomain of gH, whereas 6E3 required residues 1 to 629 of gH. The strain-specific determinant for neutralization by Mab 2B10 was identified as a single Met→Ile amino acid polymorphism within gH, located within the central part of the protein. The polymorphism is evenly distributed among described HCMV strains. The 2B10 epitope thus represents a novel strain-specific antibody target site on gH of HCMV. The dependence of the reactivity of 2B10 on the simultaneous presence of gB/gH/gL will be of value in the structural definition of this tripartite complex. The 2B10 epitope may also represent a valuable tool for diagnostics to monitor infections/reinfections with different HCMV strains during pregnancy or after transplantation. IMPORTANCE HCMV infections are life threatening to people with compromised or immature immune systems. Understanding the antiviral antibody repertoire induced during HCMV infection is a necessary prerequisite to define protective antibody responses. Here, we report three novel anti-gH MAbs that potently neutralized HCMV infectivity. One of these MAbs (2B10) targets a novel strain-specific conformational epitope on gH that only becomes accessible upon coexpression of the minimal fusion machinery gB/gH/gL. Strain specificity is dependent on a single amino acid polymorphism within gH. Our data highlight the importance of strain-specific neutralizing antibody responses against HCMV. The 2B10 epitope may also represent a valuable tool for diagnostics to monitor infections/reinfections with different HCMV strains during pregnancy or after transplantation. In addition, the dependence of the reactivity of 2B10 on the simultaneous presence of gB/gH/gL will be of value in the structural definition of this tripartite complex.
Collapse
|
47
|
Schultz EP, Yu Q, Stegmann C, Day LZ, Lanchy JM, Ryckman BJ. Mutagenesis of Human Cytomegalovirus Glycoprotein L Disproportionately Disrupts gH/gL/gO over gH/gL/pUL128-131. J Virol 2021; 95:e0061221. [PMID: 34132577 PMCID: PMC8354327 DOI: 10.1128/jvi.00612-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 06/04/2021] [Indexed: 01/14/2023] Open
Abstract
Cell-free and cell-to-cell spread of herpesviruses involves a core fusion apparatus comprised of the fusion protein glycoprotein B (gB) and the regulatory factor gH/gL. The human cytomegalovirus (HCMV) gH/gL/gO and gH/gL/pUL128-131 facilitate spread in different cell types. The gO and pUL128-131 components bind distinct receptors, but how the gH/gL portions of the complexes functionally compare is not understood. We previously characterized a panel of gL mutants by transient expression and showed that many were impaired for gH/gL-gB-dependent cell-cell fusion but were still able to form gH/gL/pUL128-131 and induce receptor interference. Here, the gL mutants were engineered into the HCMV BAC clones TB40/e-BAC4 (TB), TR, and Merlin (ME), which differ in their utilization of the two complexes for entry and spread. Several of the gL mutations disproportionately impacted gH/gL/gO-dependent entry and spread over gH/gL/pUL128-131 processes. The effects of some mutants could be explained by impaired gH/gL/gO assembly, but other mutants impacted gH/gL/gO function. Soluble gH/gL/gO containing the L201 mutant failed to block HCMV infection despite unimpaired binding to PDGFRα, indicating the existence of other important gH/gL/gO receptors. Another mutant (L139) enhanced the gH/gL/gO-dependent cell-free spread of TR, suggesting a "hyperactive" gH/gL/gO. Recently published crystallography and cryo-electron microscopy studies suggest structural conservation of the gH/gL underlying gH/gL/gO and gH/gL/pUL128-131. However, our data suggest important differences in the gH/gL of the two complexes and support a model in which gH/gL/gO can provide an activation signal for gB. IMPORTANCE The endemic betaherpesvirus HCMV circulates in human populations as a complex mixture of genetically distinct variants, establishes lifelong persistent infections, and causes significant disease in neonates and immunocompromised adults. This study capitalizes on our recent characterizations of three genetically distinct HCMV BAC clones to discern the functions of the envelope glycoprotein complexes gH/gL/gO and gH/gL/pUL128-13, which are promising vaccine targets that share the herpesvirus core fusion apparatus component, gH/gL. Mutations in the shared gL subunit disproportionally affected gH/gL/gO, demonstrating mechanistic differences between the two complexes, and may provide a basis for more refined evaluations of neutralizing antibodies.
Collapse
Affiliation(s)
- Eric P. Schultz
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
- Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, Montana, USA
| | - Qin Yu
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Cora Stegmann
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Le Zhang Day
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
- Biochemistry and Biophysics Program, University of Montana, Missoula, Montana, USA
| | - Jean-Marc Lanchy
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Brent J. Ryckman
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
- Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, Montana, USA
- Biochemistry and Biophysics Program, University of Montana, Missoula, Montana, USA
| |
Collapse
|
48
|
Braun B, Sinzger C. Transmission of cell-associated human cytomegalovirus isolates between various cell types using polymorphonuclear leukocytes as a vehicle. Med Microbiol Immunol 2021; 210:197-209. [PMID: 34091753 PMCID: PMC8286230 DOI: 10.1007/s00430-021-00713-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 05/15/2021] [Indexed: 12/25/2022]
Abstract
Polymorphonuclear leukocytes (PMNs) are regarded as vehicles for the hematogenous dissemination of human cytomegalovirus (HCMV). In cell culture, this concept has been validated with cell-free laboratory strains but not yet with clinical HCMV isolates that grow strictly cell-associated. We, therefore, aimed to evaluate whether PMNs can also transmit such isolates from initially infected fibroblasts to other cell types, which might further clarify the role of PMNs in HCMV dissemination and provide a model to search for potential inhibitors. PMNs, which have been isolated from HCMV-seronegative individuals, were added for 3 h to fibroblasts infected with recent cell-associated HCMV isolates, then removed and transferred to various recipient cell cultures. The transfer efficiency in the recipient cultures was evaluated by immunofluorescence staining of viral immediate early antigens. Soluble derivatives of the cellular HCMV entry receptor PDGFRα were analyzed for their potential to interfere with this transfer. All of five tested HCMV isolates could be transferred to fibroblasts, endothelial and epithelial cells with transfer rates ranging from 2 to 9%, and the transferred viruses could spread focally in these recipient cells within 1 week. The PDGFRα-derived peptides IK40 and GT40 reduced transfer by 40 and 70% when added during the uptake step. However, when added during the transfer step, only IK40 was effective, inhibiting transmission by 20% on endothelial cells and 50–60% on epithelial cells and fibroblasts. These findings further corroborate the assumption of cell-associated HCMV dissemination by PMNs and demonstrate that it is possible to inhibit this transmission mode.
Collapse
Affiliation(s)
- Berenike Braun
- Institute for Virology, Ulm University Medical Center, Ulm, Germany.
| | | |
Collapse
|
49
|
Chaudhry MZ, Messerle M, Čičin-Šain L. Construction of Human Cytomegalovirus Mutants with Markerless BAC Mutagenesis. Methods Mol Biol 2021; 2244:133-158. [PMID: 33555586 DOI: 10.1007/978-1-0716-1111-1_8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
To fully understand the function of cytomegalovirus (CMV) genes, it is imperative that they are studied in the context of infection. Therefore, the targeted deletion of individual viral genes and the comparison of these loss-of-function viral mutants to the wild-type virus allow for the identification of the relevance and role for a particular gene in the viral replication cycle. Targeted CMV mutagenesis has made huge advances over the past 20 years. The cloning of CMV genomes into Escherichia coli as bacterial artificial chromosomes (BAC) allows for not only quick and efficient deletion of viral genomic regions, individual genes, or single-nucleotide exchanges in the viral genome but also the insertion of heterologous genetic sequences for gain-of-function approaches. The conceptual advantage of this strategy is that it overcomes the restrictions of recombinant technologies in cell culture systems. Namely, recombination in infected cells occurs only in a few clones, and their selection is not possible if the targeted genes are relevant for virus replication and are not able to compete for growth against the unrecombined parental viruses. On the other hand, BAC mutagenesis enables the selection for antibiotic resistance in E. coli, providing selective growth advantage to the recombined genomes and thus clonal selection of viruses with even extremely poor fitness. Here we describe the methods used for the generation of a CMV BAC, targeted mutagenesis of BAC clones, and transfection of human cells with CMV BAC DNA in order to reconstitute the viral infection process.
Collapse
Affiliation(s)
- M Zeeshan Chaudhry
- Department of Vaccinology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Martin Messerle
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Luka Čičin-Šain
- Department of Vaccinology, Helmholtz Centre for Infection Research, Braunschweig, Germany. .,Center for Individualized Infection Medicine (CIIM), A Joint Venture of HZI and MHH, Braunschweig, Germany.
| |
Collapse
|
50
|
Vezzani G, Amendola D, Yu D, Chandramouli S, Frigimelica E, Maione D, Merola M. The Human Cytomegalovirus UL116 Glycoprotein Is a Chaperone to Control gH-Based Complexes Levels on Virions. Front Microbiol 2021; 12:630121. [PMID: 33889136 PMCID: PMC8056026 DOI: 10.3389/fmicb.2021.630121] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 02/22/2021] [Indexed: 01/14/2023] Open
Abstract
Human cytomegalovirus (HCMV) relies in large part upon the viral membrane fusion glycoprotein B and two alternative gH/gL complexes, gH/gL/gO (Trimer) and gH/gL/UL128/UL130/UL131A (Pentamer) to enter into cells. The relative amounts of Trimer and Pentamer vary among HCMV strains and contribute to differences in cell tropism. Although the viral ER resident protein UL148 has been shown to interact with gH to facilitate gO incorporation, the mechanisms that favor the assembly and maturation of one complex over another remain poorly understood. HCMV virions also contain an alternative non-disulfide bound heterodimer comprised of gH and UL116 whose function remains unknown. Here, we show that disruption of HCMV gene UL116 causes infectivity defects of ∼10-fold relative to wild-type virus and leads to reduced expression of both gH/gL complexes in virions. Furthermore, gH that is not covalently bound to other viral glycoproteins, which are readily detected in wild-type HCMV virions, become undetectable in the absence of UL116 suggesting that the gH/UL116 complex is abundant in virions. We find evidence that UL116 and UL148 interact during infection indicating that the two proteins might cooperate to regulate the abundance of HCMV gH complexes. Altogether, these results are consistent with a role of UL116 as a chaperone for gH during the assembly and maturation of gH complexes in infected cells.
Collapse
Affiliation(s)
- Giacomo Vezzani
- GSK, Siena, Italy.,Department of Pharmacy and Biotechnology (FABIT), University of Bologna, Bologna, Italy
| | | | - Dong Yu
- GSK, Rockville, MD, United States
| | | | | | | | - Marcello Merola
- GSK, Siena, Italy.,Department of Biology, University of Naples Federico II, Naples, Italy
| |
Collapse
|