1
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Atanasoff KE, Parsons AJ, Ophir SI, Lurain N, Kraus T, Moran T, Duty JA, Tortorella D. A broadly neutralizing human monoclonal antibody generated from transgenic mice immunized with HCMV particles limits virus infection and proliferation. J Virol 2024:e0021324. [PMID: 38832789 DOI: 10.1128/jvi.00213-24] [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: 01/31/2024] [Accepted: 05/07/2024] [Indexed: 06/05/2024] Open
Abstract
Human cytomegalovirus (HCMV) is a β-herpesvirus that poses severe disease risk for immunocompromised patients who experience primary infection or reactivation. Development and optimization of safe and effective anti-HCMV therapeutics is of urgent necessity for the prevention and treatment of HCMV-associated diseases in diverse populations. The use of neutralizing monoclonal antibodies (mAbs) to limit HCMV infection poses a promising therapeutic strategy, as anti-HCMV mAbs largely inhibit infection by targeting virion glycoprotein complexes. In contrast, the small-molecule compounds currently approved for patients (e.g., ganciclovir, letermovir, and maribavir) target later stages of the HCMV life cycle. Here, we present a broadly neutralizing human mAb, designated 1C10, elicited from a VelocImmune mouse immunized with infectious HCMV particles. Clone 1C10 neutralizes infection after virion binding to cells by targeting gH/gL envelope complexes and potently reduces infection of diverse HCMV strains in fibroblast, trophoblast, and epithelial cells. Antibody competition assays found that 1C10 recognizes a region of gH associated with broad neutralization and binds to soluble pentamer in the low nanomolar range. Importantly, 1C10 treatment significantly reduced virus proliferation in both fibroblast and epithelial cells. Further, the combination treatment of mAb 1C10 with ganciclovir reduced HCMV infection and proliferation in a synergistic manner. This work characterizes a neutralizing human mAb for potential use as a HCMV treatment, as well as a possible therapeutic strategy utilizing combination-based treatments targeting disparate steps of the viral life cycle. Collectively, the findings support an antibody-based therapy to effectively treat patients at risk for HCMV-associated diseases. IMPORTANCE Human cytomegalovirus is a herpesvirus that infects a large proportion of the population and can cause significant disease in diverse patient populations whose immune systems are suppressed or compromised. The development and optimization of safe anti-HCMV therapeutics, especially those that have viral targets and inhibition mechanisms different from current HCMV treatments, are of urgent necessity to better public health. Human monoclonal antibodies (mAbs) that prevent HCMV entry of cells were identified by immunizing transgenic mice and screened for broad and effective neutralization capability. Here, we describe one such mAb, which was found to target gH/gL envelope complexes and effectively limit HCMV infection and dissemination. Further, administration of the antibody in combination with the antiviral drug ganciclovir inhibited HCMV in a synergistic manner, highlighting this approach and the use of anti-HCMV mAbs more broadly, as a potential therapeutic strategy for the treatment of diverse patient populations.
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Affiliation(s)
- Kristina E Atanasoff
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Andrea J Parsons
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Sabrina I Ophir
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Nell Lurain
- Department of Immunology-Microbiology, Rush University, Chicago, Illinois, USA
| | - Thomas Kraus
- Center for Therapeutic Antibody Development, Drug Discovery Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Thomas Moran
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- Center for Therapeutic Antibody Development, Drug Discovery Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - J Andrew Duty
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- Center for Therapeutic Antibody Development, Drug Discovery Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Domenico Tortorella
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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2
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Zhang M, Wang X, Li J, Peng F, Liu Z, Chen ZS. Ligands and receptors in human cytomegalovirus entry: Current therapies and new directions. Drug Discov Today 2024; 29:103833. [PMID: 37992888 DOI: 10.1016/j.drudis.2023.103833] [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: 08/20/2023] [Revised: 11/11/2023] [Accepted: 11/16/2023] [Indexed: 11/24/2023]
Abstract
The demand for human cytomegalovirus (HCMV) vaccines was first raised by a committee convened during the 1990s. A comprehensive investigation into the mechanism of viral infection supports the prioritization of developing drugs or vaccines that specifically target receptors and ligands involved in the infection process. As primary targets for neutralizing antibodies to combat HCMV, viral ligands (trimer, pentamer, and glycoprotein B) have crucial roles and exhibit substantial antiviral potential, which could be exploited for breakthroughs in antiviral research.
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Affiliation(s)
- Min Zhang
- School of Clinical Medicine, Weifang Medical University, Weifang 261053, China
| | - Xiaochen Wang
- Department of Medical Microbiology, Basic Medical College, Weifang Medical University, Weifang 261053, China
| | - Jianshe Li
- School of Clinical Medicine, Weifang Medical University, Weifang 261053, China
| | - Fujun Peng
- School of Basic Medical Sciences, Weifang Medical University, Weifang 261053, China.
| | - Zhijun Liu
- Department of Medical Microbiology, Basic Medical College, Weifang Medical University, Weifang 261053, China.
| | - Zhe-Sheng Chen
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St John's University, Queens, NY 11439, USA.
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3
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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.
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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
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4
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Boppana SB, van Boven M, Britt WJ, Gantt S, Griffiths PD, Grosse SD, Hyde TB, Lanzieri TM, Mussi-Pinhata MM, Pallas SE, Pinninti SG, Rawlinson WD, Ross SA, Vossen ACTM, Fowler KB. Vaccine value profile for cytomegalovirus. Vaccine 2023; 41 Suppl 2:S53-S75. [PMID: 37806805 DOI: 10.1016/j.vaccine.2023.06.020] [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: 01/24/2023] [Revised: 04/28/2023] [Accepted: 06/02/2023] [Indexed: 10/10/2023]
Abstract
Cytomegalovirus (CMV) is the most common infectious cause of congenital malformation and a leading cause of developmental disabilities such as sensorineural hearing loss (SNHL), motor and cognitive deficits. The significant disease burden from congenital CMV infection (cCMV) led the US National Institute of Medicine to rank CMV vaccine development as the highest priority. An average of 6.7/1000 live births are affected by cCMV, but the prevalence varies across and within countries. In contrast to other congenital infections such as rubella and toxoplasmosis, the prevalence of cCMV increases with CMV seroprevalence rates in the population. The true global burden of cCMV disease is likely underestimated because most infected infants (85-90 %) have asymptomatic infection and are not identified. However, about 7-11 % of those with asymptomatic infection will develop SNHL throughout early childhood. Although no licensed CMV vaccine exists, several candidate vaccines are in development, including one currently in phase 3 trials. Licensure of one or more vaccine candidates is feasible within the next five years. Various models of CMV vaccine strategies employing different target populations have shown to provide substantial benefit in reducing cCMV. Although CMV can cause end-organ disease with significant morbidity and mortality in immunocompromised individuals, the focus of this vaccine value profile (VVP) is on preventing or reducing the cCMV disease burden. This CMV VVP provides a high-level, comprehensive assessment of the currently available data to inform the potential public health, economic, and societal value of CMV vaccines. The CMV VVP was developed by a working group of subject matter experts from academia, public health groups, policy organizations, and non-profit organizations. All contributors have extensive expertise on various elements of the CMV VVP and have described the state of knowledge and identified the current gaps. The VVP was developed using only existing and publicly available information.
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Affiliation(s)
- Suresh B Boppana
- Departments of Pediatrics and Microbiology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Michiel van Boven
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, and Julius Center for Health Sciences and Primary Care, Department of Epidemiology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - William J Britt
- Departments of Pediatrics, Microbiology, and Neurobiology, Heersink School of Medicine, University of Alabama at Birmingham, USA
| | - Soren Gantt
- Centre de recherche du CHU Sainte-Justine, Montréal, QC H3T 1C5, Canada
| | - Paul D Griffiths
- Emeritus Professor of Virology, University College London, United Kingdom
| | - Scott D Grosse
- National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA
| | - Terri B Hyde
- Global Immunization Division, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Tatiana M Lanzieri
- Measles, Rubella, and Cytomegalovirus Epidemiology Team, Viral Vaccine Preventable Diseases Branch / Division of Viral Diseases. National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Marisa M Mussi-Pinhata
- Department of Pediatrics, Ribeirão Preto Medical School, University of São Paulo, Brazil
| | - Sarah E Pallas
- Global Immunization Division, Center for Global Health, U.S. Centers for Disease Control and Prevention, Atlanta, GA 30329-4027, USA
| | - Swetha G Pinninti
- Departments of Pediatrics and Microbiology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - William D Rawlinson
- Serology and Virology Division, NSW Health Pathology Randwick, Prince of Wales Hospital, Sydney, Australia; School of Biotechnology and Biomolecular Sciences, and School of Medical Sciences, University of New South Wales, Sydney, Australia
| | - Shannon A Ross
- Departments of Pediatrics and Microbiology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Ann C T M Vossen
- Department of Medical Microbiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Karen B Fowler
- Departments of Pediatrics and Epidemiology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
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5
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Semmes EC, Miller IG, Rodgers N, Phan CT, Hurst JH, Walsh KM, Stanton RJ, Pollara J, Permar SR. ADCC-activating antibodies correlate with decreased risk of congenital human cytomegalovirus transmission. JCI Insight 2023; 8:e167768. [PMID: 37427588 PMCID: PMC10371338 DOI: 10.1172/jci.insight.167768] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 05/23/2023] [Indexed: 07/11/2023] Open
Abstract
Human cytomegalovirus (HCMV) is the most common vertically transmitted infection worldwide, yet there are no vaccines or therapeutics to prevent congenital HCMV (cCMV) infection. Emerging evidence indicates that antibody Fc effector functions may be a previously underappreciated component of maternal immunity against HCMV. We recently reported that antibody-dependent cellular phagocytosis (ADCP) and IgG activation of FcγRI/FcγRII were associated with protection against cCMV transmission, leading us to hypothesize that additional Fc-mediated antibody functions may be important. In this same cohort of HCMV-transmitting (n = 41) and nontransmitting (n = 40) mother-infant dyads, we report that higher maternal sera antibody-dependent cellular cytotoxicity (ADCC) activation is also associated with lower risk of cCMV transmission. We investigated the relationship between ADCC and IgG responses against 9 viral antigens and found that ADCC activation correlated most strongly with sera IgG binding to the HCMV immunoevasin protein UL16. Moreover, we determined that higher UL16-specific IgG binding and FcγRIII/CD16 engagement were associated with the greatest risk reduction in cCMV transmission. Our findings indicate that ADCC-activating antibodies against targets such as UL16 may represent an important protective maternal immune response against cCMV infection that can guide future HCMV correlates studies and vaccine or antibody-based therapeutic development.
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Affiliation(s)
- Eleanor C. Semmes
- Medical Scientist Training Program, Department of Molecular Genetics and Microbiology, and
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
| | - Itzayana G. Miller
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
- Department of Pediatrics, Weill Cornell Medicine, New York City, New York, USA
| | - Nicole Rodgers
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina, USA
| | - Caroline T. Phan
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
| | - Jillian H. Hurst
- Department of Pediatrics, Duke University, Durham, North Carolina, USA
| | - Kyle M. Walsh
- Department of Pediatrics, Duke University, Durham, North Carolina, USA
- Department of Neurosurgery, Duke University, Durham, North Carolina, USA
| | - Richard J. Stanton
- Division of Infection and Immunology, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Justin Pollara
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina, USA
| | - Sallie R. Permar
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
- Department of Pediatrics, Weill Cornell Medicine, New York City, New York, USA
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6
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Gomes AC, Baraniak IA, McIntosh MR, Sodi I, Langstone T, Siddiqui S, Atkinson C, McLean GR, Griffiths PD, Reeves MB. A temperature-dependent virus-binding assay reveals the presence of neutralizing antibodies in human cytomegalovirus gB vaccine recipients' sera. J Gen Virol 2023; 104:001860. [PMID: 37310000 PMCID: PMC10661908 DOI: 10.1099/jgv.0.001860] [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: 03/22/2023] [Accepted: 05/15/2023] [Indexed: 06/14/2023] Open
Abstract
Human cytomegalovirus (HCMV) remains an important cause of mortality in immune-compromised transplant patients and following congenital infection. Such is the burden, an effective vaccine strategy is considered to be of the highest priority. The most successful vaccines to date have focused on generating immune responses against glycoprotein B (gB) - a protein essential for HCMV fusion and entry. We have previously reported that an important component of the humoral immune response elicited by gB/MF59 vaccination of patients awaiting transplant is the induction of non-neutralizing antibodies that target cell-associated virus with little evidence of concomitant classical neutralizing antibodies. Here we report that a modified neutralization assay that promotes prolonged binding of HCMV to the cell surface reveals the presence of neutralizing antibodies in sera taken from gB-vaccinated patients that cannot be detected using standard assays. We go on to show that this is not a general feature of gB-neutralizing antibodies, suggesting that specific antibody responses induced by vaccination could be important. Although we can find no evidence that these neutralizing antibody responses are a correlate of protection in vivo in transplant recipients their identification demonstrates the utility of the approach in identifying these responses. We hypothesize that further characterization has the potential to aid the identification of functions within gB that are important during the entry process and could potentially improve future vaccine strategies directed against gB if they prove to be effective against HCMV at higher concentrations.
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Affiliation(s)
- Ariane C. Gomes
- Institute of Immunity and Transplantation, Division of Infection and Immunity, UCL, Royal Free Campus, London, NW3 2PP, UK
| | - Ilona A. Baraniak
- Institute of Immunity and Transplantation, Division of Infection and Immunity, UCL, Royal Free Campus, London, NW3 2PP, UK
| | - Megan R. McIntosh
- Institute of Immunity and Transplantation, Division of Infection and Immunity, UCL, Royal Free Campus, London, NW3 2PP, UK
| | - Isabella Sodi
- Institute of Immunity and Transplantation, Division of Infection and Immunity, UCL, Royal Free Campus, London, NW3 2PP, UK
| | - Toby Langstone
- Institute of Immunity and Transplantation, Division of Infection and Immunity, UCL, Royal Free Campus, London, NW3 2PP, UK
| | - Saima Siddiqui
- London Metropolitan University, School of Human Sciences, London, N7 8DB, UK
| | - Claire Atkinson
- Institute of Immunity and Transplantation, Division of Infection and Immunity, UCL, Royal Free Campus, London, NW3 2PP, UK
| | - Gary R. McLean
- London Metropolitan University, School of Human Sciences, London, N7 8DB, UK
- Imperial College London, National Heart and Lung Institute, London, W2 1PG, UK
| | - Paul D. Griffiths
- Institute of Immunity and Transplantation, Division of Infection and Immunity, UCL, Royal Free Campus, London, NW3 2PP, UK
| | - Matthew B. Reeves
- Institute of Immunity and Transplantation, Division of Infection and Immunity, UCL, Royal Free Campus, London, NW3 2PP, UK
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7
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Semmes EC, Miller IG, Rodgers N, Phan CT, Hurst JH, Walsh KM, Stanton RJ, Pollara J, Permar SR. ADCC-activating antibodies correlate with protection against congenital human cytomegalovirus infection. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.03.15.23287332. [PMID: 36993668 PMCID: PMC10055595 DOI: 10.1101/2023.03.15.23287332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Human cytomegalovirus (HCMV) is the most common vertically transmitted infection worldwide, yet there are no licensed vaccines or therapeutics to prevent congenital HCMV (cCMV) infection. Emerging evidence from studies of natural infection and HCMV vaccine trials indicates that antibody Fc effector functions may defend against HCMV infection. We previously reported that antibody-dependent cellular phagocytosis (ADCP) and IgG activation of FcγRI/FcγRII were associated with reduced risk of cCMV transmission, leading us to hypothesize that other Fc-mediated antibody functions may also contribute to protection. In this same cohort of HCMV transmitting (n = 41) and non-transmitting (n = 40) mother-infant dyads, we found that higher maternal sera antibody-dependent cellular cytotoxicity (ADCC) activation was also associated with decreased risk of cCMV infection. We determined that NK cell-mediated ADCC responses correlated strongly with anti-HCMV IgG FcγRIII/CD16 activation and IgG binding to the HCMV immunoevasin protein UL16. Notably, anti-UL16 IgG binding and engagement of FcγRIII/CD16 were higher in non-transmitting versus transmitting dyads and interacted significantly with ADCC responses. These findings indicate that ADCC-activating antibodies against novel targets such as UL16 may represent an important protective maternal immune response against cCMV infection, which can guide future HCMV correlates studies and vaccine development.
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8
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Fornara C, Schultz E, Lilleri D, Baldanti F, Ryckman B, Gerna G. Fibroblast, Epithelial and Endothelial Cell-Derived Human Cytomegalovirus Strains Display Distinct Neutralizing Antibody Responses and Varying Levels of gH/gL Complexes. Int J Mol Sci 2023; 24:4417. [PMID: 36901847 PMCID: PMC10003051 DOI: 10.3390/ijms24054417] [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: 12/23/2022] [Revised: 02/03/2023] [Accepted: 02/16/2023] [Indexed: 02/25/2023] Open
Abstract
In sequential sera from pregnant women with HCMV primary infection (PI), the serum neutralizing activity is higher against virions produced in epithelial and endothelial cells than in fibroblasts. Immunoblotting shows that the pentamer complex/trimer complex (PC/TC) ratio varies according to the producer cell culture type used for the virus preparation to be employed in the neutralizing antibody (NAb) assay, and is lower in fibroblasts and higher in epithelial, and especially endothelial cells. The blocking activity of TC- and PC-specific inhibitors varies according to the PC/TC ratio of virus preparations. The rapid reversion of the virus phenotype following its back passage to the original cell culture (fibroblasts) potentially argues in favor of a producer cell effect on virus phenotype. However, the role of genetic factors cannot be overlooked. In addition to the producer cell type, the PC/TC ratio may differ in single HCMV strains. In conclusion, the NAb activity not only varies with different HCMV strains, but is a dynamic parameter changing according to virus strain, type of target and producer cells, and number of cell culture passages. These findings may have some important implications for the development of both therapeutic antibodies and subunit vaccines.
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Affiliation(s)
- Chiara Fornara
- Microbiology and Virology Unit, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
| | - Eric Schultz
- Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT 59812, USA
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Daniele Lilleri
- Microbiology and Virology Unit, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
| | - Fausto Baldanti
- Microbiology and Virology Unit, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
- Department of Clinical, Surgical, Diagnostic and Pediatric Sciences, University of Pavia, 27100 Pavia, Italy
| | - Brent Ryckman
- Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT 59812, USA
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Giuseppe Gerna
- Laboratories of Genetics, Transplantology and Cardiovascular Diseases, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy
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9
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Davies EL, Noor M, Lim EY, Houldcroft CJ, Okecha G, Atkinson C, Reeves MB, Jackson SE, Wills MR. HCMV carriage in the elderly diminishes anti-viral functionality of the adaptive immune response resulting in virus replication at peripheral sites. Front Immunol 2022; 13:1083230. [PMID: 36591233 PMCID: PMC9797693 DOI: 10.3389/fimmu.2022.1083230] [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: 10/28/2022] [Accepted: 11/18/2022] [Indexed: 12/23/2022] Open
Abstract
Human cytomegalovirus (HCMV) infection and periodic reactivation is, generally, well controlled by adaptative immune responses in the healthy. In older people, overt HCMV disease is rarely seen despite the association of HCMV with increased risk of mortality; evidence from studies of unwell aged populations suggest that HCMV seropositivity is an important co-morbidity factor. HCMV genomes have been detected in urine from older donors, suggesting that the immune response prevents systemic disease but possibly immunomodulation due to lifelong viral carriage may alter its efficacy at peripheral tissue sites. Previously we have demonstrated that there were no age-related expansions of T cell responses to HCMV or increase in latent viral carriage with age and these T cells produced anti-viral cytokines and viremia was very rarely detected. To investigate the efficacy of anti-HCMV responses with increasing age, we used an in vitro Viral Dissemination Assay (VDA) using autologous dermal fibroblasts to determine the anti-viral effector capacity of total PBMC, as well as important subsets (T cells, NK cells). In parallel we assessed components of the humoral response (antibody neutralization) and combined this with qPCR detection of HCMV in blood, saliva and urine in a cohort of young and old donors. Consistent with previous studies, we again show HCMV specific cIL-10, IFNγ and TNFα T cell responses to peptides did not show an age-related defect. However, assessment of direct anti-viral cellular and antibody-mediated adaptive immune responses using the VDA shows that older donors are significantly less able to control viral dissemination in an in vitro assay compared to young donors. Corroborating this observation, we detected viral genomes in saliva samples only from older donors, these donors had a defect in cellular control of viral spread in our in vitro assay. Phenotyping of fibroblasts used in this study shows expression of a number of checkpoint inhibitor ligands which may contribute to the defects observed. The potential to therapeutically intervene in checkpoint inhibitor pathways to prevent HCMV reactivation in the unwell aged is an exciting avenue to explore.
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Affiliation(s)
- Emma L. Davies
- Department of Medicine, Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge School of Clinical Medicine, Cambridge, United Kingdom
| | - Mahlaqua Noor
- Department of Medicine, Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge School of Clinical Medicine, Cambridge, United Kingdom
| | - Eleanor Y. Lim
- Department of Medicine, Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge School of Clinical Medicine, Cambridge, United Kingdom
| | - Charlotte J. Houldcroft
- Department of Medicine, Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge School of Clinical Medicine, Cambridge, United Kingdom
| | - Georgina Okecha
- Department of Medicine, Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge School of Clinical Medicine, Cambridge, United Kingdom
| | - Claire Atkinson
- Institute of Immunity and Transplantation, Division of Infection and Immunity, University College London, London, United Kingdom
| | - Matthew B. Reeves
- Institute of Immunity and Transplantation, Division of Infection and Immunity, University College London, London, United Kingdom
| | - Sarah E. Jackson
- Department of Medicine, Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge School of Clinical Medicine, Cambridge, United Kingdom,*Correspondence: Sarah E. Jackson, ; Mark R. Wills,
| | - Mark R. Wills
- Department of Medicine, Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge School of Clinical Medicine, Cambridge, United Kingdom,*Correspondence: Sarah E. Jackson, ; Mark R. Wills,
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10
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Cardani‐Boulton A, Boylan BT, Stetsenko V, Bergmann CC. B cells going viral in the CNS: Dynamics, complexities, and functions of B cells responding to viral encephalitis. Immunol Rev 2022; 311:75-89. [PMID: 35984298 PMCID: PMC9804320 DOI: 10.1111/imr.13124] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A diverse number of DNA and RNA viruses have the potential to invade the central nervous system (CNS), causing inflammation and injury to cells that have a limited capacity for repair and regeneration. While rare, viral encephalitis in humans is often fatal and survivors commonly suffer from permanent neurological sequelae including seizures. Established treatment options are extremely limited, predominantly relying on vaccines, antivirals, or supportive care. Many viral CNS infections are characterized by the presence of antiviral antibodies in the cerebral spinal fluid (CSF), indicating local maintenance of protective antibody secreting cells. However, the mechanisms maintaining these humoral responses are poorly characterized. Furthermore, while both viral and autoimmune encephalitis are associated with the recruitment of diverse B cell subsets to the CNS, their protective and pathogenic roles aside from antibody production are just beginning to be understood. This review will focus on the relevance of B cell responses to viral CNS infections, with an emphasis on the importance of intrathecal immunity and the potential contribution to autoimmunity. Specifically, it will summarize the newest data characterizing B cell activation, differentiation, migration, and localization in clinical samples as well as experimental models of acute and persistent viral encephalitis.
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Affiliation(s)
| | - Brendan T. Boylan
- Cleveland Clinic Lerner Research Institute, NeuroscienceClevelandOhioUSA,Case Western Reserve University School of Medicine, PathologyClevelandOhioUSA
| | - Volodymyr Stetsenko
- Cleveland Clinic Lerner Research Institute, NeuroscienceClevelandOhioUSA,Kent State University, School of Biomedical SciencesKentOhioUSA
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11
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Semmes EC, Miller IG, Wimberly CE, Phan CT, Jenks JA, Harnois MJ, Berendam SJ, Webster H, Hurst JH, Kurtzberg J, Fouda GG, Walsh KM, Permar SR. Maternal Fc-mediated non-neutralizing antibody responses correlate with protection against congenital human cytomegalovirus infection. J Clin Invest 2022; 132:e156827. [PMID: 35763348 PMCID: PMC9374380 DOI: 10.1172/jci156827] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 06/24/2022] [Indexed: 01/05/2023] Open
Abstract
Human cytomegalovirus (HCMV) is the most common congenital infection and a leading cause of stillbirth, neurodevelopmental impairment, and pediatric hearing loss worldwide. Development of a maternal vaccine or therapeutic to prevent congenital HCMV has been hindered by limited knowledge of the immune responses that protect against HCMV transmission in utero. To identify protective antibody responses, we measured HCMV-specific IgG binding and antiviral functions in paired maternal and cord blood sera from HCMV-seropositive transmitting (n = 41) and non-transmitting (n = 40) mother-infant dyads identified via a large, US-based, public cord blood bank. We found that high-avidity IgG binding to HCMV and antibody-dependent cellular phagocytosis (ADCP) were associated with reduced risk of congenital HCMV infection. We also determined that HCMV-specific IgG activation of FcγRI and FcγRII was enhanced in non-transmitting dyads and that increased ADCP responses were mediated through both FcγRI and FcγRIIA expressed on human monocytes. These findings suggest that engagement of FcγRI/FcγRIIA and Fc effector functions including ADCP may protect against congenital HCMV infection. Taken together, these data can guide future prospective studies on immune correlates against congenital HCMV transmission and inform HCMV vaccine and immunotherapeutic development.
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Affiliation(s)
- Eleanor C. Semmes
- Medical Scientist Training Program, Department of Molecular Genetics and Microbiology and
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
- Duke Children’s Health & Discovery Initiative, Duke University, Durham, North Carolina, USA
| | - Itzayana G. Miller
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
- Department of Pediatrics, Weill Cornell School of Medicine, New York, New York, USA
| | - Courtney E. Wimberly
- Duke Children’s Health & Discovery Initiative, Duke University, Durham, North Carolina, USA
- Department of Neurosurgery and
| | - Caroline T. Phan
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
| | - Jennifer A. Jenks
- Medical Scientist Training Program, Department of Molecular Genetics and Microbiology and
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
| | - Melissa J. Harnois
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
| | - Stella J. Berendam
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
| | - Helen Webster
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
| | - Jillian H. Hurst
- Duke Children’s Health & Discovery Initiative, Duke University, Durham, North Carolina, USA
- Department of Pediatrics, Duke University, Durham, North Carolina, USA
| | - Joanne Kurtzberg
- Department of Pediatrics, Duke University, Durham, North Carolina, USA
- Carolinas Cord Blood Bank, Duke University Medical Center, Durham, North Carolina, USA
| | - Genevieve G. Fouda
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
- Duke Children’s Health & Discovery Initiative, Duke University, Durham, North Carolina, USA
| | - Kyle M. Walsh
- Duke Children’s Health & Discovery Initiative, Duke University, Durham, North Carolina, USA
- Department of Neurosurgery and
| | - Sallie R. Permar
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, USA
- Duke Children’s Health & Discovery Initiative, Duke University, Durham, North Carolina, USA
- Department of Pediatrics, Weill Cornell School of Medicine, New York, New York, USA
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12
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Dasari V, Beckett K, Horsefield S, Ambalathingal G, Khanna R. A bivalent CMV vaccine formulated with human compatible TLR9 agonist CpG1018 elicits potent cellular and humoral immunity in HLA expressing mice. PLoS Pathog 2022; 18:e1010403. [PMID: 35737741 PMCID: PMC9223316 DOI: 10.1371/journal.ppat.1010403] [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: 03/01/2022] [Accepted: 05/26/2022] [Indexed: 11/30/2022] Open
Abstract
There is now convincing evidence that the successful development of an effective CMV vaccine will require improved formulation and adjuvant selection that is capable of inducing both humoral and cellular immune responses. Here, we have designed a novel bivalent subunit vaccine formulation based on CMV-encoded oligomeric glycoprotein B (gB) and polyepitope protein in combination with human compatible TLR9 agonist CpG1018. The polyepitope protein includes multiple minimal HLA class I-restricted CD8+ T cell epitopes from different antigens of CMV. This subunit vaccine generated durable anti-viral antibodies, CMV-specific CD4+ and CD8+ T cell responses in multiple HLA expressing mice. Antibody responses included broad TH1 isotypes (IgG2a, IgG2b and IgG3) and potently neutralized CMV infection in fibroblasts and epithelial cells. Furthermore, polyfunctional antigen-specific T cell immunity and antiviral antibody responses showed long-term memory maintenance. These observations argue that this novel vaccine strategy, if applied to humans, could facilitate the generation of robust humoral and cellular immune responses which may be more effective in preventing CMV-associated complications in various clinical settings. Human Cytomegalovirus (CMV) is a significant human pathogen. Generally, in healthy people CMV causes mild symptomatic disease, but during pregnancy CMV can transmit from mother to foetus (1 out of every 200 live births worldwide) and lead to sensorineural hearing loss, vision impairment and central nervous system damage. In transplant patients, CMV can cause serious complications leading to organ rejection and even death. Currently, there is no licensed vaccine available to prevent CMV-associated complications in pregnant women and transplant patients. Here, we have developed a novel bivalent CMV vaccine formulation consisting of recombinant CMVpoly and gB proteins in combination with human compatible adjuvant CpG1018. Preclinical immunogenicity evaluation in multiple HLA expressing mice demonstrated that bivalent CMV vaccine formulation consistently generated robust CMV-specific neutralising antibodies, CD4+ and CD8+ T cell responses. More importantly, long-term follow-up analysis showed that the CMV vaccine can induce durable CMV-specific humoral and cellular immune responses. Our results support further development of this bivalent subunit CMV vaccine to test safety, immunogenicity and efficacy in humans.
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Affiliation(s)
- Vijayendra Dasari
- QIMR Berghofer Centre for Immunotherapy and Vaccine Development and Tumour Immunology Laboratory, Department of Immunology, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- * E-mail: (VD); (RK)
| | - Kirrilee Beckett
- QIMR Berghofer Centre for Immunotherapy and Vaccine Development and Tumour Immunology Laboratory, Department of Immunology, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Shane Horsefield
- QIMR Berghofer Centre for Immunotherapy and Vaccine Development and Tumour Immunology Laboratory, Department of Immunology, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - George Ambalathingal
- QIMR Berghofer Centre for Immunotherapy and Vaccine Development and Tumour Immunology Laboratory, Department of Immunology, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Rajiv Khanna
- QIMR Berghofer Centre for Immunotherapy and Vaccine Development and Tumour Immunology Laboratory, Department of Immunology, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- * E-mail: (VD); (RK)
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13
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Parsons AJ, Ophir SI, Duty JA, Kraus TA, Stein KR, Moran TM, Tortorella D. Development of broadly neutralizing antibodies targeting the cytomegalovirus subdominant antigen gH. Commun Biol 2022; 5:387. [PMID: 35468974 PMCID: PMC9038728 DOI: 10.1038/s42003-022-03294-z] [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: 09/25/2021] [Accepted: 03/17/2022] [Indexed: 11/08/2022] Open
Abstract
Human cytomegalovirus (HCMV) is a β-herpesvirus that increases morbidity and mortality in immunocompromised individuals including transplant recipients and newborns. New anti-HCMV therapies are an urgent medical need for diverse patient populations. HCMV infection of a broad range of host tissues is dependent on the gH/gL/gO trimer and gH/gL/UL28/UL130/UL131A pentamer complexes on the viral envelope. We sought to develop safe and effective therapeutics against HCMV by generating broadly-neutralizing, human monoclonal antibodies (mAbs) from VelocImmune® mice immunized with gH/gL cDNA. Following high-throughput binding and neutralization screening assays, 11 neutralizing antibodies were identified with unique CDR3 regions and a high-affinity (KD 1.4-65 nM) to the pentamer complex. The antibodies bound to distinct regions within Domains 1 and 2 of gH and effectively neutralized diverse clinical strains in physiologically relevant cell types including epithelial cells, trophoblasts, and monocytes. Importantly, combined adminstration of mAbs with ganciclovir, an FDA approved antiviral, greatly limited virus dissemination. Our work identifies several anti-gH/gL mAbs and sheds light on gH neutralizing epitopes that can guide future vaccine strategies.
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Affiliation(s)
- Andrea J Parsons
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Sabrina I Ophir
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - J Andrew Duty
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Center of Therapeutic Antibody Development, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Thomas A Kraus
- Center of Therapeutic Antibody Development, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Kathryn R Stein
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Thomas M Moran
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Center of Therapeutic Antibody Development, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Domenico Tortorella
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
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14
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Chin A, Liu J, Jardetzky T, Johnson DC, Vanarsdall A. Identification of functionally important domains of human cytomegalovirus gO that act after trimer binding to receptors. PLoS Pathog 2022; 18:e1010452. [PMID: 35452493 PMCID: PMC9032346 DOI: 10.1371/journal.ppat.1010452] [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: 07/02/2021] [Accepted: 03/17/2022] [Indexed: 11/18/2022] Open
Abstract
Human cytomegalovirus (HCMV) entry involves trimer (gH/gL/gO) that interacts with PDGFRα in fibroblasts. Entry into epithelial and endothelial cells requires trimer, which binds unidentified receptors, and pentamer (gH/gL/UL128-131), which binds neuropilin-2. To identify functionally important domains in trimer, we screened an overlapping 20-mer gO peptide library and identified two sets of peptides: 19/20 (a.a. 235–267) and 32/33 (a.a. 404–436) that could block virus entry. Soluble trimer containing wild type gO blocked HCMV entry, whereas soluble trimers with the 19/20 or 32/33 sequences mutated did not block entry. Interestingly, the mutant trimers retained the capacity to bind to cellular receptors including PDGFRα. Peptide 19/20 and 32/33 sequences formed a lobe extending from the surface of gO and an adjacent concave structure, respectively. Neither of these sets of sequences contacted PDGFRα. Instead, our data support a model in which the 19/20 and 32/33 trimer sequences function downstream of receptor binding, e.g. trafficking of HCMV into endosomes or binding to gB for entry fusion. We also screened for peptides that bound antibodies (Abs) in human sera, observing that peptides 20 and 26 bound Abs. These peptides engendered neutralizing Abs (NAbs) after immunization of rabbits and could pull out NAbs from human sera. Peptides 20 and 26 sequences represent the first NAb epitopes identified in trimer. These studies describe two important surfaces on gO defined by: i) peptides 19/20 and 32/33, which apparently act downstream of receptor binding and ii) peptide 26 that interacts with PDGFRα. Both these surfaces are targets of NAbs. Human cytomegalovirus (HCMV) infects 80% of the world population, causing severe morbidity and mortality in transplant patients and can be transmitted to the developing fetus leading to severe neurological defects. The current anti-viral agents used to treat HCMV are not very effective as viruses can develop resistance and there is no licensed HCMV vaccine available. Recently, there has been intense interest in the HCMV envelope glycoproteins involved in entry as a component of vaccines. One glycoprotein complex, the gH/gL/gO trimer is especially intriguing as it is required for infection of extracellular virus in all cell types. Here, we identify domains in the trimer that have an essential function in entry downstream of receptor binding and are also epitopes recognized by naturally induced neutralizing antibodies. These results will have implications for advancing the efforts to develop novel HCMV therapeutics.
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Affiliation(s)
- Andrea Chin
- Department of Molecular Microbiology & Immunology, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Jing Liu
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Theodore Jardetzky
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California, United States of America
| | - David C. Johnson
- Department of Molecular Microbiology & Immunology, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Adam Vanarsdall
- Department of Molecular Microbiology & Immunology, Oregon Health & Science University, Portland, Oregon, United States of America
- * E-mail:
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15
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Wrapp D, Ye X, Ku Z, Su H, Jones HG, Wang N, Mishra AK, Freed DC, Li F, Tang A, Li L, Jaijyan DK, Zhu H, Wang D, Fu TM, Zhang N, An Z, McLellan JS. Structural basis for HCMV Pentamer recognition by neuropilin 2 and neutralizing antibodies. SCIENCE ADVANCES 2022; 8:eabm2546. [PMID: 35275718 PMCID: PMC8916728 DOI: 10.1126/sciadv.abm2546] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Human cytomegalovirus (HCMV) encodes multiple surface glycoprotein complexes to infect a variety of cell types. The HCMV Pentamer, composed of gH, gL, UL128, UL130, and UL131A, enhances entry into epithelial, endothelial, and myeloid cells by interacting with the cell surface receptor neuropilin 2 (NRP2). Despite the critical nature of this interaction, the molecular determinants that govern NRP2 recognition remain unclear. Here, we describe the cryo-EM structure of NRP2 bound to Pentamer. The high-affinity interaction between these proteins is calcium dependent and differs from the canonical carboxyl-terminal arginine (CendR) binding that NRP2 typically uses. We also determine the structures of four neutralizing human antibodies bound to the HCMV Pentamer to define susceptible epitopes. Two of these antibodies compete with NRP2 binding, but the two most potent antibodies recognize a previously unidentified epitope that does not overlap the NRP2-binding site. Collectively, these findings provide a structural basis for HCMV tropism and antibody-mediated neutralization.
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Affiliation(s)
- Daniel Wrapp
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Xiaohua Ye
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Zhiqiang Ku
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Hang Su
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Harrison G. Jones
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Nianshuang Wang
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Akaash K. Mishra
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Daniel C. Freed
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033, USA
| | - Fengsheng Li
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033, USA
| | - Aimin Tang
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033, USA
| | - Leike Li
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Dabbu Kumar Jaijyan
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers New Jersey Medical School, Newark, NJ 07103, USA
| | - Hua Zhu
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers New Jersey Medical School, Newark, NJ 07103, USA
| | - Dai Wang
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033, USA
| | - Tong-Ming Fu
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Ningyan Zhang
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Zhiqiang An
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- Corresponding author. (Z.A.); (J.S.M.)
| | - Jason S. McLellan
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
- Corresponding author. (Z.A.); (J.S.M.)
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16
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Huang Y, Tang J, Wang H, Yu H, Song Q, Guo X, Li C, Wang J, Liang C, Li S, Li S, Lin Z, Chen Q, Zhong G, Zhuang S, Su Y, Li T, Wu T, Ge S, Zhang J, Xia N. Pre-existing maternal IgG antibodies as a protective factor against congenital cytomegalovirus infection: A mother-child prospective cohort study. EBioMedicine 2022; 77:103885. [PMID: 35183868 PMCID: PMC8861648 DOI: 10.1016/j.ebiom.2022.103885] [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: 10/29/2021] [Revised: 01/25/2022] [Accepted: 02/01/2022] [Indexed: 11/10/2022] Open
Abstract
Background An understanding of the correlation between maternal immunity and congenital cytomegalovirus (CMV) infection is critical for informing the design and evaluation of an effective maternal vaccine. This study aimed to quantitatively measure the protective effect of pre-existing maternal immunity against congenital CMV (cCMV) infection. Methods A mother-child cohort study was conducted in three maternal and child health hospitals in China from 2015 to 2018. Pregnant women were consecutively enrolled, and anti-CMV pp150 IgG concentration at early, middle and late gestational ages were evaluated. Their newborns were screened for cCMV infection by CMV-DNA testing of saliva and urine. Findings In total, 6729 pregnant women were enrolled, and 6602 of them (98·11%) were positive for CMV IgG at their early gestational age visit (median time: 13 gestational weeks (GW); time range: 6–25 GW). In total, 6228 live newborns were born to seropositive mothers, and 48 (0·77%) of these infants were diagnosed with cCMV infection. The geometric mean concentration (GMC) of CMV IgG at an early gestational age in the women who delivered cCMV-positive newborns (i.e., the transmitters) was 8·54 IU/mL; this was significantly lower than the GMC in the non-transmitters (11·01 IU/mL; P=0·04). In early gestation, the risk of cCMV infection decreased as maternal IgG antibody levels increased (P=0·020); however, the same was not true in middle or late gestation (P>0·05). Using receiver operating characteristic analysis, a CMV IgG concentration of 12·83 IU/mL was established as the optimal diagnostic threshold. Compared to lower levels of CMV IgG (<12·83 IU/mL) in seropositive pregnant women, higher maternal CMV IgG levels (≥12·83 IU/mL) were associated with a 50% reduction in cCMV infection risk in infants (relative risk=0·50; 95% confidence interval: 0·27–0·93; P=0·028). Interpretation For seropositive women, a higher level of CMV IgG at an early gestational age is associated with a lower risk of cCMV infection in their newborns. Funding National Natural Science Foundation of China; Science and Technology Key Project in Fujian Province; Merck Sharp & Dohme Corp., Kenilworth, NJ, USA; Fieldwork Funds for graduate students of Xiamen University.
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17
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Gonzalez-Del Pino GL, Heldwein EE. Well Put Together—A Guide to Accessorizing with the Herpesvirus gH/gL Complexes. Viruses 2022; 14:v14020296. [PMID: 35215889 PMCID: PMC8874593 DOI: 10.3390/v14020296] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/20/2022] [Accepted: 01/22/2022] [Indexed: 02/06/2023] Open
Abstract
Herpesviruses are enveloped, double-stranded DNA viruses that infect a variety of hosts across the animal kingdom. Nine of these establish lifelong infections in humans, for which there are no cures and few vaccine or treatment options. Like all enveloped viruses, herpesviruses enter cells by fusing their lipid envelopes with a host cell membrane. Uniquely, herpesviruses distribute the functions of receptor engagement and membrane fusion across a diverse cast of glycoproteins. Two glycoprotein complexes are conserved throughout the three herpesvirus subfamilies: the trimeric gB that functions as a membrane fusogen and the heterodimeric gH/gL, the role of which is less clearly defined. Here, we highlight the conserved and divergent functions of gH/gL across the three subfamilies of human herpesviruses by comparing its interactions with a broad range of accessory viral proteins, host cell receptors, and neutralizing or inhibitory antibodies. We propose that the intrinsic structural plasticity of gH/gL enables it to function as a signal integration machine that can accept diverse regulatory inputs and convert them into a “trigger” signal that activates the fusogenic ability of gB.
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18
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Talavera-Barber M, Flint K, Graber B, Dhital R, Kaptsan I, Medoro AK, Sánchez PJ, Shimamura M. Antibody Titers Against Human Cytomegalovirus gM/gN and gB Among Pregnant Women and Their Infants. Front Pediatr 2022; 10:846254. [PMID: 35813379 PMCID: PMC9259787 DOI: 10.3389/fped.2022.846254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 05/12/2022] [Indexed: 11/13/2022] Open
Abstract
Congenital CMV (cCMV) infection can affect infants born to mothers with preconceptional seroimmunity. To prevent cCMV due to nonprimary maternal infection, vaccines eliciting responses exceeding natural immunity may be required. Anti-gM/gN antibodies have neutralizing capacity in-vitro and in animal models, but anti-gM/gN antibodies have not been characterized among seroimmune pregnant women. Paired maternal and infant cord sera from 92 CMV seropositive mothers and their full-term or preterm infants were tested for anti-gM/gN antibody titers in comparison with anti-gB titers and neutralizing activity. Anti-gM/gN titers were significantly lower than anti-gB titers for all groups and did not correlate with serum neutralizing capacity. Further study is needed to determine if higher anti-gM/gN antibody titers might enhance serum neutralizing capacity among seropositive adults.
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Affiliation(s)
- Maria Talavera-Barber
- Avera McKennan Hospital and University Medical Center, Avera Research Institute, Sioux Falls, SD, United States
| | - Kaitlyn Flint
- Center for Vaccines and Immunity, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States
| | - Brianna Graber
- Center for Vaccines and Immunity, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States
| | - Ravi Dhital
- Center for Vaccines and Immunity, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States
| | - Irina Kaptsan
- Center for Vaccines and Immunity, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States
| | - Alexandra K Medoro
- Division of Neonatology, Department of Pediatrics, Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, OH, United States.,Division of Infectious Diseases, Department of Pediatrics, Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, OH, United States
| | - Pablo J Sánchez
- Division of Neonatology, Department of Pediatrics, Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, OH, United States.,Division of Infectious Diseases, Department of Pediatrics, Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, OH, United States.,Center for Perinatal Research, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States
| | - Masako Shimamura
- Center for Vaccines and Immunity, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,Division of Infectious Diseases, Department of Pediatrics, Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, OH, United States
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19
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Schleiss MR, Fernández-Alarcón C, Hernandez-Alvarado N, Wang JB, Geballe AP, McVoy MA. Inclusion of the Guinea Pig Cytomegalovirus Pentameric Complex in a Live Virus Vaccine Aids Efficacy against Congenital Infection but Is Not Essential for Improving Maternal and Neonatal Outcomes. Viruses 2021; 13:v13122370. [PMID: 34960639 PMCID: PMC8706200 DOI: 10.3390/v13122370] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/19/2021] [Accepted: 11/20/2021] [Indexed: 01/17/2023] Open
Abstract
The development of a vaccine against congenital human cytomegalovirus (HCMV) infection is a major priority. The pentameric complex (PC) of virion envelope proteins gH, gL, UL128, UL130, and UL131A is a key vaccine target. To determine the importance of immunity to the homologous PC encoded by guinea pig cytomegalovirus (GPCMV) in preventing congenital CMV, PC-intact and PC-deficient live-attenuated vaccines were generated and directly compared for immunogenicity and efficacy against vertical transmission in a vertical transmission model. A virulent PC-intact GPCMV (PC/intact) was modified by galK mutagenesis either to abrogate PC expression (PC/null; containing a frame-shift mutation in GP129, homolog of UL128) or to delete genes encoding three MHC Class I homologs and a protein kinase R (PKR) evasin while retaining the PC (3DX/Δ145). Attenuated vaccines were compared to sham immunization in a two-dose preconception subcutaneous inoculation regimen in GPCMV seronegative Hartley guinea pigs. Vaccines induced transient, low-grade viremia in 5/12 PC/intact-, 2/12 PC/null-, and 1/11 3DX/Δ145-vaccinated animals. Upon completion of the two-dose vaccine series, ELISA titers for the PC/intact group (geometic mean titer (GMT) 13,669) were not significantly different from PC/null (GMT 8127) but were significantly higher than for the 3DX/Δ145 group (GMT 6185; p < 0.01). Dams were challenged with salivary gland-adapted GPCMV in the second trimester. All vaccines conferred protection against maternal viremia. Newborn weights were significantly lower in sham-immunized controls (84.5 ± 2.4 g) compared to PC/intact (96 ± 2.3 g), PC/null (97.6 ± 1.9 g), or 3DX/Δ145 (93 ± 1.7) pups (p < 0.01). Pup mortality in sham-immunized controls was 29/40 (73%) and decreased to 1/44 (2.3%), 2/46 (4.3%), or 4/40 (10%) in PC/intact, PC/null, or 3DX/Δ145 groups, respectively (all p < 0.001 compared to control). Congenital GPCMV transmission occurred in 5/44 (11%), 16/46 (35%), or 29/38 (76%) of pups in PC/intact, PC/null, or 3DX/Δ145 groups, versus 36/40 (90%) in controls. For infected pups, viral loads were lower in pups born to vaccinated dams compared to controls. Sequence analysis demonstrated that infected pups in the vaccine groups had salivary gland-adapted GPCMV and not vaccine strain-specific sequences, indicating that congenital transmission was due to the challenge virus and not vaccine virus. We conclude that inclusion of the PC in a live, attenuated preconception vaccine improves immunogenicity and reduces vertical transmission, but PC-null vaccines are equal to PC-intact vaccines in reducing maternal viremia and protecting against GPCMV-related pup mortality.
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Affiliation(s)
- Mark R. Schleiss
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN 55455, USA; (C.F.-A.); (N.H.-A.)
- Correspondence: ; Tel.: +1-612-626-9913
| | - Claudia Fernández-Alarcón
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN 55455, USA; (C.F.-A.); (N.H.-A.)
| | - Nelmary Hernandez-Alvarado
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN 55455, USA; (C.F.-A.); (N.H.-A.)
| | - Jian Ben Wang
- Department of Pediatrics, Virginia Commonwealth University, Richmond, VA 23298, USA; (J.B.W.); (M.A.M.)
| | - Adam P. Geballe
- Divisions of Human Biology and Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA;
| | - Michael A. McVoy
- Department of Pediatrics, Virginia Commonwealth University, Richmond, VA 23298, USA; (J.B.W.); (M.A.M.)
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20
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Cryo-Electron Microscopy Structure and Interactions of the Human Cytomegalovirus gHgLgO Trimer with Platelet-Derived Growth Factor Receptor Alpha. mBio 2021; 12:e0262521. [PMID: 34700375 PMCID: PMC8546573 DOI: 10.1128/mbio.02625-21] [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] [Indexed: 01/16/2023] Open
Abstract
Human cytomegalovirus (HCMV) is a herpesvirus that produces disease in transplant patients and newborn children. Entry of HCMV into cells relies on gH/gL trimer (gHgLgO) and pentamer (gHgLUL128–131) complexes that bind cellular receptors. Here, we studied the structure and interactions of the HCMV trimer, formed by AD169 strain gH and gL and TR strain gO proteins, with the human platelet-derived growth factor receptor alpha (PDGFRα). Three trimer surfaces make extensive contacts with three PDGFRα N-terminal domains, causing PDGFRα to wrap around gO in a structure similar to a human hand, explaining the high-affinity interaction. gO is among the least conserved HCMV proteins, with 8 distinct genotypes. We observed high conservation of residues mediating gO-gL interactions but more extensive gO variability in the PDGFRα interface. Comparisons between our trimer structure and a previously determined structure composed of different subunit genotypes indicate that gO variability is accommodated by adjustments in the gO-PDGFRα interface. We identified two loops within gO that were disordered and apparently glycosylated, which could be deleted without disrupting PDGFRα binding. We also identified four gO residues that contact PDGFRα, which when mutated produced markedly reduced receptor binding. These residues fall within conserved contact sites of gO with PDGFRα and may represent key targets for anti-trimer neutralizing antibodies and HCMV vaccines. Finally, we observe that gO mutations distant from the gL interaction site impact trimer expression, suggesting that the intrinsic folding or stability of gO can impact the efficiency of trimer assembly.
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21
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Using Split Luciferase Assay and anti-HSV Glycoprotein Monoclonal Antibodies to Predict a Functional Binding Site Between gD and gH/gL. J Virol 2021; 95:JVI.00053-21. [PMID: 33504603 PMCID: PMC8103690 DOI: 10.1128/jvi.00053-21] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Herpes simplex virus (HSV) entry and cell-cell fusion require glycoproteins gD, gH/gL, and gB. HSV entry begins with gD binding its receptor (nectin-1), which then activates gH/gL to enable the conversion of pre-fusion gB to its active form to promote membrane fusion. Virus-neutralizing monoclonal antibodies (Mabs) interfere with one or more of these steps and localization of their epitopes identifies functional sites on each protein. Utilizing this approach, we have identified the gH/gL binding face on gD and the corresponding gD binding site on gH/gL. Here, we used combinations of these Mabs to define the orientation of gD and gH/gL relative to each other. We reasoned that if two Mabs, one directed at gD and the other at gH/gL, block fusion more effectively than when either were used alone (additive), then their epitopes would be spatially distanced and binding of one would not directly interfere with binding of the other during fusion. However, if the two Mabs blocked fusion with equal or lesser efficacy that when either were used alone (indifferent), we propose that their epitopes would be in close proximity in the complex. Using a live cell fusion assay, we found that some Mab pairings blocked the fusion with different mechanisms while other had a similar mechanisms of action. Grouping the different combinations of antibodies into indifferent and additive groups, we present a model for the orientation of gD vis-à-vis gH/gL in the complex.Importance: Virus entry and cell-cell fusion mediated by HSV require four essential glycoproteins, gD, gH/gL, gB and a gD receptor. Virus-neutralizing antibodies directed against any of these proteins bind to residues within key functional sites and interfere with essential steps in the fusion pathway. Thus, the epitopes of these Mabs overlap and point to critical, functional sites on their target proteins. Here, we combined gD and gH/gL antibodies to determine whether they work in an additive or non-additive (indifferent) fashion to block specific events in glycoprotein-driven cell-cell fusion. Identifying combinations of antibodies that have additive effects will help in the rational design of an effective therapeutic "polyclonal antibody" to treat HSV disease. In addition, identification of the exact contact regions between gD and gH/gL can inform the design of small molecules that would interfere with the gD-gH/gL complex formation, thus preventing the virus from entering the host cell.
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22
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Dorfman JR, Balla SR, Pathirana J, Groome MJ, Madhi SA, Moore PL. In utero human cytomegalovirus infection is associated with increased levels of putatively protective maternal antibodies in nonprimary infection: evidence for boosting but not protection. Clin Infect Dis 2021; 73:e981-e987. [PMID: 33560335 DOI: 10.1093/cid/ciab099] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 02/02/2021] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Although primary maternal cytomegalovirus infections are associated with higher risk of in utero transmission, most fetal infections worldwide result from nonprimary maternal infections. Antibodies directed at glycoprotein B and the gH/gL/pUL128-130-131 pentamer can neutralize virus, and higher levels of antibody directed at several particular pentamer epitopes defined by monoclonal antibodies (mAbs) are associated with reduced risk of fetal cytomegalovirus transmission during primary maternal infection. This had not been explored in maternal nonprimary infection. METHODS In a setting where most maternal cytomegalovirus infections are nonprimary, 42 mothers of infants with congenital CMV infections (transmitters) were compared to 75 cytomegalovirus-seropositive mothers whose infants were cytomegalovirus-uninfected (nontransmitters). Control infants were matched by sex, maternal HIV status and gestational age. We measured the ability of maternal antibodies to block three key pentameric epitopes: one in the gH subunit, another straddling UL130/UL131 and the third straddling gH/gL/UL128/UL130. We tested if levels of antibodies directed at these epitopes were higher in nontransmitters compared to transmitters. RESULTS Levels of all three putatively protective pentamer-directed antibodies were significantly higher in transmitters compared to nontransmitters. In contrast, antibodies targeting an epitope on glycoprotein B were not different. Total antibody specific for pentamer and for gB were also higher in transmitters. CONCLUSIONS We found no evidence that higher levels of any CMV-specific antibodies were associated with reduced risk of congenital CMV infection in nonprimary maternal infection. Instead, we found higher maternal antibody targeting epitopes on CMV pentamer in transmitters than nontransmitters, providing evidence for antibody boosting but not protection.
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Affiliation(s)
- Jeffrey R Dorfman
- South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, South Africa
- Department of Science/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa
- Division of Medical Virology, Department of Pathology, Stellenbosch University, Cape Town, South Africa
| | - Sashkia R Balla
- Centre for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa
- Antibody Immunity Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Jayani Pathirana
- South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, South Africa
- Department of Science/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa
| | - Michelle J Groome
- South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, South Africa
- Department of Science/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa
| | - Shabir A Madhi
- South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, South Africa
- Department of Science/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa
| | - Penny L Moore
- Centre for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa
- Antibody Immunity Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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23
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Abstract
The way to a successful vaccine against human cytomegalovirus is hampered by the peculiar biology of this infection. However, some candidate vaccines have been shown to protect seronegative women and transplant recipients, and we should know soon whether they can prevent congenital infection.
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Affiliation(s)
- Stanley A Plotkin
- Department of Pediatrics, University of Pennsylvania, Vaxconsult, Doylestown, Pennsylvania, USA
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24
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Boppana SB, Britt WJ. Recent Approaches and Strategies in the Generation of Anti-human Cytomegalovirus Vaccines. Methods Mol Biol 2021; 2244:403-463. [PMID: 33555597 DOI: 10.1007/978-1-0716-1111-1_19] [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: 12/23/2022]
Abstract
Human cytomegalovirus is the largest human herpesvirus and shares many core features of other herpesviruses such as tightly regulated gene expression during genome replication and latency as well as the establishment of lifelong persistence following infection. In contrast to stereotypic clinical syndromes associated with alpha-herpesvirus infections, almost all primary HCMV infections are asymptomatic and acquired early in life in most populations in the world. Although asymptomatic in most individuals, HCMV is a major cause of disease in hosts with deficits in adaptive and innate immunity such as infants who are infected in utero and allograft recipients following transplantation. Congenital HCMV is a commonly acquired infection in the developing fetus that can result in a number of neurodevelopmental abnormalities. Similarly, HCMV is a major cause of disease in allograft recipients in the immediate and late posttransplant period and is thought to be a major contributor to chronic allograft rejection. Even though HCMV induces robust innate and adaptive immune responses, it also encodes a vast array of immune evasion functions that are thought aid in its persistence. Immune correlates of protective immunity that prevent or modify intrauterine HCMV infection remain incompletely defined but are thought to consist primarily of adaptive responses in the pregnant mother, thus making congenital HCMV a potentially vaccine modifiable disease. Similarly, HCMV infection in allograft recipients is often more severe in recipients without preexisting adaptive immunity to HCMV. Thus, there has been a considerable effort to modify HCMV specific immunity in transplant recipient either through active immunization or passive transfer of adaptive effector functions. Although efforts to develop an efficacious vaccine and/or passive immunotherapy to limit HCMV disease have been underway for nearly six decades, most have met with limited success at best. In contrast to previous efforts, current HCMV vaccine development has relied on observations of unique properties of HCMV in hopes of reproducing immune responses that at a minimum will be similar to that following natural infection. However, more recent findings have suggested that immunity following naturally acquired HCMV infection may have limited protective activity and almost certainly, is not sterilizing. Such observations suggest that either the induction of natural immunity must be specifically tailored to generate protective activity or alternatively, that providing targeted passive immunity to susceptible populations could be prove to be more efficacious.
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Affiliation(s)
- Suresh B Boppana
- Departments of Pediatrics, The University of Alabama at Birmingham, Birmingham, AL, USA.,Departments of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - William J Britt
- Departments of Pediatrics, The University of Alabama at Birmingham, Birmingham, AL, USA. .,Departments of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, USA. .,Departments of Neurobiology, The University of Alabama at Birmingham, Birmingham, AL, USA.
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25
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Forrest C, Gomes A, Reeves M, Male V. NK Cell Memory to Cytomegalovirus: Implications for Vaccine Development. Vaccines (Basel) 2020; 8:vaccines8030394. [PMID: 32698362 PMCID: PMC7563466 DOI: 10.3390/vaccines8030394] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 07/13/2020] [Accepted: 07/15/2020] [Indexed: 12/20/2022] Open
Abstract
Natural killer (NK) cells are innate lymphoid cells that recognize and eliminate virally-infected and cancerous cells. Members of the innate immune system are not usually considered to mediate immune memory, but over the past decade evidence has emerged that NK cells can do this in several contexts. Of these, the best understood and most widely accepted is the response to cytomegaloviruses, with strong evidence for memory to murine cytomegalovirus (MCMV) and several lines of evidence suggesting that the same is likely to be true of human cytomegalovirus (HCMV). The importance of NK cells in the context of HCMV infection is underscored by the armory of NK immune evasion genes encoded by HCMV aimed at subverting the NK cell immune response. As such, ongoing studies that have utilized HCMV to investigate NK cell diversity and function have proven instructive. Here, we discuss our current understanding of NK cell memory to viral infection with a focus on the response to cytomegaloviruses. We will then discuss the implications that this will have for the development of a vaccine against HCMV with particular emphasis on how a strategy that can harness the innate immune system and NK cells could be crucial for the development of a vaccine against this high-priority pathogen.
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Affiliation(s)
- Calum Forrest
- Institute of Immunity & Transplantation, UCL, Royal Free Campus, London NW3 2PF, UK; (C.F.); (A.G.)
| | - Ariane Gomes
- Institute of Immunity & Transplantation, UCL, Royal Free Campus, London NW3 2PF, UK; (C.F.); (A.G.)
| | - Matthew Reeves
- Institute of Immunity & Transplantation, UCL, Royal Free Campus, London NW3 2PF, UK; (C.F.); (A.G.)
- Correspondence: (M.R.); (V.M.)
| | - Victoria Male
- Department of Metabolism, Digestion and Reproduction, Imperial College London, Chelsea and Westminster Campus, London SW10 9NH, UK
- Correspondence: (M.R.); (V.M.)
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26
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Park J, Gill KS, Aghajani AA, Heredia JD, Choi H, Oberstein A, Procko E. Engineered receptors for human cytomegalovirus that are orthogonal to normal human biology. PLoS Pathog 2020; 16:e1008647. [PMID: 32559251 PMCID: PMC7329128 DOI: 10.1371/journal.ppat.1008647] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 07/01/2020] [Accepted: 05/20/2020] [Indexed: 12/12/2022] Open
Abstract
A trimeric glycoprotein complex on the surface of human cytomegalovirus (HCMV) binds to platelet-derived growth factor (PDGF) receptor α (PDGFRα) to mediate host cell recognition and fusion of the viral and cellular membranes. Soluble PDGFRα potently neutralizes HCMV in tissue culture, and its potential use as an antiviral therapeutic has the benefit that any escape mutants will likely be attenuated. However, PDGFRα binds multiple PDGF ligands in the human body as part of developmental programs in embryogenesis and continuing through adulthood. Any therapies with soluble receptor therefore come with serious efficacy and safety concerns, especially for the treatment of congenital HCMV. Soluble virus receptors that are orthogonal to human biology might resolve these concerns. This engineering problem is solved by deep mutational scanning on the D2-D3 domains of PDGFRα to identify variants that maintain interactions with the HCMV glycoprotein trimer in the presence of competing PDGF ligands. Competition by PDGFs is conformation-dependent, whereas HCMV trimer binding is independent of proper D2-D3 conformation, and many mutations at the receptor-PDGF interface are suitable for functionally separating trimer from PDGF interactions. Purified soluble PDGFRα carrying a targeted mutation succeeded in displaying wild type affinity for HCMV trimer with a simultaneous loss of PDGF binding, and neutralizes trimer-only and trimer/pentamer-expressing HCMV strains infecting fibroblasts or epithelial cells. Overall, this work makes important progress in the realization of soluble HCMV receptors for clinical application. Human cytomegalovirus (HCMV) causes severe disease in transplant recipients and immunocompromised patients, and infections in a fetus or neonate are responsible for life-long neurological defects. Cell entry is in part mediated by a trimeric glycoprotein complex on the viral surface, which binds tightly to the host receptor PDGFRα. The soluble extracellular region of PDGFRα can be used as an antiviral agent to potently neutralize the virus in vitro. However, PDGFRα ordinarily binds growth factors in the human body to regulate developmental programs, which will limit the in vivo efficacy and safety of soluble PDGFRα. Using saturation mutagenesis and selections in human cell culture, mutations in PDGFRα are identified that eliminate off-target growth factor interactions while preserving HCMV binding and neutralization.
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Affiliation(s)
- Jihye Park
- Department of Biochemistry, University of Illinois, Urbana, Illinois, United States of America
| | - Kevin Sean Gill
- Department of Biochemistry, University of Illinois, Urbana, Illinois, United States of America
| | - Ali Asghar Aghajani
- Department of Biochemistry, University of Illinois, Urbana, Illinois, United States of America
| | - Jeremiah Dallas Heredia
- Department of Biochemistry, University of Illinois, Urbana, Illinois, United States of America
| | - Hannah Choi
- Department of Biochemistry, University of Illinois, Urbana, Illinois, United States of America
| | - Adam Oberstein
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Erik Procko
- Department of Biochemistry, University of Illinois, Urbana, Illinois, United States of America
- Cancer Center at Illinois (CCIL), University of Illinois, Urbana, Illinois, United States of America
- * E-mail:
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27
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Limaye AP, Green ML, Edmison BC, Stevens-Ayers T, Chatterton-Kirchmeier S, Geballe AP, Singh N, Boeckh M. Prospective Assessment of Cytomegalovirus Immunity in High-Risk Donor-Seropositive/Recipient-Seronegative Liver Transplant Recipients Receiving Either Preemptive Therapy or Antiviral Prophylaxis. J Infect Dis 2020; 220:752-760. [PMID: 31112280 DOI: 10.1093/infdis/jiz181] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 04/22/2019] [Indexed: 12/29/2022] Open
Abstract
The differential impact of preemptive therapy (PET) and antiviral prophylaxis (AP) on development of cytomegalovirus (CMV)-specific neutralizing antibody (nAb) and T-cell responses have not previously been directly compared in high-risk donor-seropositive/recipient-seronegative (D+R-) organ transplant recipients. We prospectively assessed T-cell and nAb responses 3 months after transplantation in cohorts of high-risk D+R- liver transplant recipients who received either PET (n = 15) or AP (n = 25) and a control group of CMV-seropositive transplant recipients (R+) (AP; n = 24). CMV phosphoprotein 65 (pp65)- and immediate early protein 1-specific multifunctional T-cell responses were determined by means of intracellular cytokine staining and nAbs against BADrUL131-Y4 CMV in adult retinal pigment epithelial cell line-19 human epithelial cells; nAbs were detected in 8 of 12 (67%) in the PET group, none of 17 in the AP group, and 20 of 22 (91%) in the R+ group. Multifunctional CD8 and CD4 T-cell responses to pp65 were generally similar between PET and R+ groups, and lower for the AP group; multifunctional CD4 responses were similar across all groups. Among D+R- liver transplant recipients, PET was associated with the development of greater nAb and multifunctional CD8 T-cell responses compared with AP, providing a potential mechanism to explain the relative protection against late-onset disease with PET. Future studies are needed to define specific immune parameters predictive of late-onset CMV disease with AP.
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Affiliation(s)
- Ajit P Limaye
- Department of Medicine, University of Washington, Seattle
| | - Margaret L Green
- Department of Medicine, University of Washington, Seattle.,Fred Hutchinson Cancer Research Center, Seattle
| | | | - Terry Stevens-Ayers
- Fred Hutchinson Cancer Research Center, Seattle.,Program in Infectious Diseases, VA Pittsburgh Healthcare System and University of Pittsburgh, Pennsylvania
| | - Sam Chatterton-Kirchmeier
- Fred Hutchinson Cancer Research Center, Seattle.,Program in Infectious Diseases, VA Pittsburgh Healthcare System and University of Pittsburgh, Pennsylvania
| | - Adam P Geballe
- Department of Medicine, University of Washington, Seattle.,Fred Hutchinson Cancer Research Center, Seattle.,Program in Infectious Diseases, VA Pittsburgh Healthcare System and University of Pittsburgh, Pennsylvania
| | - Nina Singh
- Program in Infectious Diseases, VA Pittsburgh Healthcare System and University of Pittsburgh, Pennsylvania
| | - Michael Boeckh
- Department of Medicine, University of Washington, Seattle.,Fred Hutchinson Cancer Research Center, Seattle.,Program in Infectious Diseases, VA Pittsburgh Healthcare System and University of Pittsburgh, Pennsylvania
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28
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Sandonís V, García-Ríos E, McConnell MJ, Pérez-Romero P. Role of Neutralizing Antibodies in CMV Infection: Implications for New Therapeutic Approaches. Trends Microbiol 2020; 28:900-912. [PMID: 32448762 DOI: 10.1016/j.tim.2020.04.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 03/31/2020] [Accepted: 04/01/2020] [Indexed: 02/06/2023]
Abstract
Cytomegalovirus (CMV) infection elicits a potent immune response that includes the stimulation of antibodies with neutralizing activity. Recent studies have focused on elucidating the role of neutralizing antibodies in protecting against CMV infection and disease and characterizing viral antigens against which neutralizing antibodies are directed. Here, we provide a synthesis of recent data regarding the role of neutralizing antibodies in protection against CMV infection/disease. We consider the role of humoral immunity in the context of the global CMV-specific immune response, and the implications that recent findings have for vaccine and antibody-based therapy design.
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Affiliation(s)
- Virginia Sandonís
- Unit of Infectious Diseases, Hospital Universitario '12 de Octubre', Instituto de Investigación Hospital '12 de Octubre' (i+12), Madrid, Spain
| | - Estéfani García-Ríos
- National Center for Microbiology, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Michael J McConnell
- National Center for Microbiology, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Pilar Pérez-Romero
- National Center for Microbiology, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain.
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29
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Human Cytomegalovirus Congenital (cCMV) Infection Following Primary and Nonprimary Maternal Infection: Perspectives of Prevention through Vaccine Development. Vaccines (Basel) 2020; 8:vaccines8020194. [PMID: 32340180 PMCID: PMC7349293 DOI: 10.3390/vaccines8020194] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 04/13/2020] [Accepted: 04/18/2020] [Indexed: 01/26/2023] Open
Abstract
Congenital cytomegalovirus (cCMV) might occur as a result of the human cytomegalovirus (HCMV) primary (PI) or nonprimary infection (NPI) in pregnant women. Immune correlates of protection against cCMV have been partly identified only for PI. Following either PI or NPI, HCMV strains undergo latency. From a diagnostic standpoint, while the serological criteria for the diagnosis of PI are well-established, those for the diagnosis of NPI are still incomplete. Thus far, a recombinant gB subunit vaccine has provided the best results in terms of partial protection. This partial efficacy was hypothetically attributed to the post-fusion instead of the pre-fusion conformation of the gB present in the vaccine. Future efforts should be addressed to verify whether a new recombinant gB pre-fusion vaccine would provide better results in terms of prevention of both PI and NPI. It is still a matter of debate whether human hyperimmune globulin are able to protect from HCMV vertical transmission. In conclusion, the development of an HCMV vaccine that would prevent a significant portion of PI would be a major step forward in the development of a vaccine for both PI and NPI.
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30
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Polymorphisms in Human Cytomegalovirus Glycoprotein O (gO) Exert Epistatic Influences on Cell-Free and Cell-to-Cell Spread and Antibody Neutralization on gH Epitopes. J Virol 2020; 94:JVI.02051-19. [PMID: 31996433 DOI: 10.1128/jvi.02051-19] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 01/24/2020] [Indexed: 02/06/2023] Open
Abstract
Human cytomegalovirus (HCMV) glycoproteins H and L (gH/gL) can be bound by either gO or the UL128 to UL131 proteins (referred to here as UL128-131) to form complexes that facilitate entry and spread, and the complexes formed are important targets of neutralizing antibodies. Strains of HCMV vary considerably in the levels of gH/gL/gO and gH/gL/UL128-131, and this can impact infectivity and cell tropism. In this study, we investigated how natural interstrain variation in the amino acid sequence of gO influences the biology of HCMV. Heterologous gO recombinants were constructed in which 6 of the 8 alleles or genotypes (GT) of gO were analyzed in the backgrounds of strains TR and Merlin (ME). The levels of gH/gL complexes were not affected, but there were impacts on entry, spread, and neutralization by anti-gH antibodies. AD169 (AD) gO (GT1a) [referred to here as ADgO(GT1a)] drastically reduced cell-free infectivity of both strains on fibroblasts and epithelial cells. PHgO(GT2a) increased cell-free infectivity of TR in both cell types, but spread in fibroblasts was impaired. In contrast, spread of ME in both cell types was enhanced by Towne (TN) gO (GT4), despite similar cell-free infectivity. TR expressing TNgO(GT4) was resistant to neutralization by anti-gH antibodies AP86 and 14-4b, whereas ADgO(GT1a) conferred resistance to 14-4b but enhanced neutralization by AP86. Conversely, ME expressing ADgO(GT1a) was more resistant to 14-4b. These results suggest that (i) there are mechanistically distinct roles for gH/gL/gO in cell-free and cell-to-cell spread, (ii) gO isoforms can differentially shield the virus from neutralizing antibodies, and (iii) effects of gO polymorphisms are epistatically dependent on other variable loci.IMPORTANCE Advances in HCMV population genetics have greatly outpaced understanding of the links between genetic diversity and phenotypic variation. Moreover, recombination between genotypes may shuffle variable loci into various combinations with unknown outcomes. UL74(gO) is an important determinant of HCMV infectivity and one of the most diverse loci in the viral genome. By analyzing interstrain heterologous UL74(gO) recombinants, we showed that gO diversity can have dramatic impacts on cell-free and cell-to-cell spread as well as on antibody neutralization and that the manifestation of these impacts can be subject to epistatic influences of the global genetic background. These results highlight the potential limitations of laboratory studies of HCMV biology that use single, isolated genotypes or strains.
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Modeling Human Cytomegalovirus-Induced Microcephaly in Human iPSC-Derived Brain Organoids. CELL REPORTS MEDICINE 2020; 1:100002. [PMID: 33205055 PMCID: PMC7659592 DOI: 10.1016/j.xcrm.2020.100002] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 01/16/2020] [Accepted: 02/28/2020] [Indexed: 12/13/2022]
Abstract
Although congenital infection by human cytomegalovirus (HCMV) is well recognized as a leading cause of neurodevelopmental defects, HCMV neuropathogenesis remains poorly understood. A major challenge for investigating HCMV-induced abnormal brain development is the strict CMV species specificity, which prevents the use of animal models to directly study brain defects caused by HCMV. We show that infection of human-induced pluripotent-stem-cell-derived brain organoids by a “clinical-like” HCMV strain results in reduced brain organoid growth, impaired formation of cortical layers, and abnormal calcium signaling and neural network activity. Moreover, we show that the impeded brain organoid development caused by HCMV can be prevented by neutralizing antibodies (NAbs) that recognize the HCMV pentamer complex. These results demonstrate in a three-dimensional cellular biosystem that HCMV can impair the development and function of the human brain and provide insights into the potential capacity of NAbs to mitigate brain defects resulted from HCMV infection. Human iPSC-derived brain organoids to model HCMV-induced brain malformation “Clinical-like” HCMV strain impairs human brain organoid growth and structure HCMV-infected brain organoids exhibit abnormal calcium signaling and neural network HCMV-induced brain organoid abnormality can be prevented by neutralizing antibodies
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Evasion of a Human Cytomegalovirus Entry Inhibitor with Potent Cysteine Reactivity Is Concomitant with the Utilization of a Heparan Sulfate Proteoglycan-Independent Route of Entry. J Virol 2020; 94:JVI.02012-19. [PMID: 31941787 PMCID: PMC7081914 DOI: 10.1128/jvi.02012-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 01/09/2020] [Indexed: 01/22/2023] Open
Abstract
The dependence of viruses on the host cell to complete their replicative cycle renders cellular functions potential targets for novel antivirals. We screened a panel of broadly acting cellular ion channel inhibitors for activity against human cytomegalovirus (HCMV) and identified the voltage-gated chloride ion channel inhibitor 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS) as a potent inhibitor of HCMV replication. Time-of-addition studies demonstrated that DIDS inhibited entry via direct interaction with the virion that impeded binding to the plasma membrane. Synthesis and analysis of pharmacological variants of DIDS suggested that intrinsic cysteine, and not lysine, reactivity was important for activity against HCMV. Although sequencing of DIDS-resistant HCMV revealed enrichment of a mutation within UL100 (encoding glycoprotein M) and a specific truncation of glycoprotein RL13, these did not explain the DIDS resistance phenotype. Specifically, only the introduction of the RL13 mutant partially phenocopied the DIDS resistance phenotype. Serendipitously, the entry of DIDS-resistant HCMV also became independent of heparan sulfate proteoglycans (HSPGs), suggesting that evasion of DIDS lowered dependence on an initial interaction with HSPGs. Intriguingly, the DIDS-resistant virus demonstrated increased sensitivity to antibody neutralization, which mapped, in part, to the presence of the gM mutation. Taken together the data characterize the antiviral activity of a novel HCMV inhibitor that drives HCMV infection to occur independently of HSPGs and the generation of increased sensitivity to humoral immunity. The data also demonstrate that compounds with cysteine reactivity have the potential to act as antiviral compounds against HCMV via direct engagement of virions.IMPORTANCE Human cytomegalovirus (HCMV) is major pathogen of nonimmunocompetent individuals that remains in need of new therapeutic options. Here, we identify a potent antiviral compound (4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid [DIDS]), its mechanism of action, and the chemical properties required for its activity. In doing so, the data argue that cysteine-reactive compounds could have the capacity to be developed for anti-HCMV activity. Importantly, the data show that entry of DIDS-resistant virus became independent of heparan sulfate proteoglycans (HSPGs) but, concomitantly, became more sensitive to neutralizing antibody responses. This serendipitous observation suggests that retention of an interaction with HSPGs during the entry process in vivo may be evolutionarily advantageous through better evasion of humoral responses directed against HCMV virions.
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Nelson CS, Baraniak I, Lilleri D, Reeves MB, Griffiths PD, Permar SR. Immune Correlates of Protection Against Human Cytomegalovirus Acquisition, Replication, and Disease. J Infect Dis 2020; 221:S45-S59. [PMID: 32134477 PMCID: PMC7057792 DOI: 10.1093/infdis/jiz428] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Human cytomegalovirus (HCMV) is the most common infectious cause of infant birth defects and an etiology of significant morbidity and mortality in solid organ and hematopoietic stem cell transplant recipients. There is tremendous interest in developing a vaccine or immunotherapeutic to reduce the burden of HCMV-associated disease, yet after nearly a half-century of research and development in this field we remain without such an intervention. Defining immune correlates of protection is a process that enables targeted vaccine/immunotherapeutic discovery and informed evaluation of clinical performance. Outcomes in the HCMV field have previously been measured against a variety of clinical end points, including virus acquisition, systemic replication, and progression to disease. Herein we review immune correlates of protection against each of these end points in turn, showing that control of HCMV likely depends on a combination of innate immune factors, antibodies, and T-cell responses. Furthermore, protective immune responses are heterogeneous, with no single immune parameter predicting protection against all clinical outcomes and stages of HCMV infection. A detailed understanding of protective immune responses for a given clinical end point will inform immunogen selection and guide preclinical and clinical evaluation of vaccines or immunotherapeutics to prevent HCMV-mediated congenital and transplant disease.
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Affiliation(s)
- Cody S Nelson
- Human Vaccine Institute, Duke University Medical Center, Durham, North Carolina,Correspondence: Cody S. Nelson, Human Vaccine Institute, Duke University Medical Center, 2 Genome Ct, Durham, NC 27710 ()
| | - Ilona Baraniak
- Institute for Immunity and Transplantation, University College London, London, United Kingdom
| | - Daniele Lilleri
- Laboratory of Genetics, Transplantation, and Cardiovascular Diseases, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Matthew B Reeves
- Institute for Immunity and Transplantation, University College London, London, United Kingdom
| | - Paul D Griffiths
- Institute for Immunity and Transplantation, University College London, London, United Kingdom
| | - Sallie R Permar
- Human Vaccine Institute, Duke University Medical Center, Durham, North Carolina
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Britt WJ. Human Cytomegalovirus Infection in Women With Preexisting Immunity: Sources of Infection and Mechanisms of Infection in the Presence of Antiviral Immunity. J Infect Dis 2020; 221:S1-S8. [PMID: 32134479 PMCID: PMC7057782 DOI: 10.1093/infdis/jiz464] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Human cytomegalovirus (HCMV) infection remains an important cause of neurodevelopmental sequelae in infants infected in utero. Unique to the natural history of perinatal HCMV infections is the occurrence of congenital HCMV infections (cCMV) in women with existing immunity to HCMV, infections that have been designated as nonprimary maternal infection. In maternal populations with a high HCMV seroprevalence, cCMV that follows nonprimary maternal infections accounts for 75%-90% of all cases of cCMV infections as well as a large proportion of infected infants with neurodevelopmental sequelae. Although considerable effort has been directed toward understanding immune correlates that can modify maternal infections and intrauterine transmission, the source of virus leading to nonprimary maternal infections and intrauterine transmission is not well defined. Previous paradigms that included reactivation of latent virus as the source of infection in immune women have been challenged by studies demonstrating acquisition and transmission of antigenically distinct viruses, a finding suggesting that reinfection through exposure to an exogenous virus is responsible for some cases of nonprimary maternal infection. Additional understanding of the source(s) of virus that leads to nonprimary maternal infection will be of considerable value in the development and testing of interventions such as vaccines designed to limit the incidence of cCMV in populations with high HCMV seroprevalence.
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Affiliation(s)
- William J Britt
- Departments of Pediatrics, Microbiology, Neurobiology, University of Alabama School of Medicine, Birmingham, Alabama
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MVA-Vectored Pentameric Complex (PC) and gB Vaccines Improve Pregnancy Outcome after Guinea Pig CMV Challenge, but Only gB Vaccine Reduces Vertical Transmission. Vaccines (Basel) 2019; 7:vaccines7040182. [PMID: 31739399 PMCID: PMC6963609 DOI: 10.3390/vaccines7040182] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 10/30/2019] [Accepted: 10/31/2019] [Indexed: 02/04/2023] Open
Abstract
(1) Background: A congenital cytomegalovirus (cCMV) vaccine is a major research priority, but the essential glycoprotein target(s) remain unclear. We compared CMV gB (gpgB), gH/gL (gp75/gL), and pentameric complex (gpPC, composed of gH/gL/GP129/GP131/GP133) vaccines in a guinea pig CMV (GPCMV) congenital infection model. (2) Methods: Modified vaccinia virus Ankara (MVA) vaccines expressing GPCMV glycoproteins were used to immunize GPCMV-seronegative, female Hartley guinea pigs (three-dose series, 3 × 107 pfu/dose). After pregnancy was established, the dams underwent an early third-trimester challenge with salivary gland (SG)-adapted GPCMV. (3) Results: All vaccines elicited GPCMV-specific binding and neutralizing antibodies. Preconception immunization resulted in 19.5-, 4.9-, and 698-fold reductions in maternal DNAemia in MVA-gp75/gL, MVA-gpPC and MVA-gpgB groups, respectively, at day 14, post-SG challenge. Vaccination improved pups’ birth weight and reduced mortality and congenital CMV transmission. In controls, cCMV infection was observed in 100% of pups (mean viral load in all visceral organs, 2.4 × 104 genomes/mg), versus 50% in the gB group (visceral viral load, 9.4 × 102 genomes/mg; p < 0.05). No significant reductions in congenital transmission were noted in the MVA-gp75/gL and MVA-gpPC groups. (4) Conclusions: MVA-vectored gB, gH/gL, and PC vaccines were immunogenic, and protected against maternal DNAemia and pup mortality. These results support the inclusion of multiple glycoprotein complexes in a cCMV vaccine.
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Inclusion of the Viral Pentamer Complex in a Vaccine Design Greatly Improves Protection against Congenital Cytomegalovirus in the Guinea Pig Model. J Virol 2019; 93:JVI.01442-19. [PMID: 31484753 DOI: 10.1128/jvi.01442-19] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 08/27/2019] [Indexed: 12/11/2022] Open
Abstract
A vaccine against congenital cytomegalovirus (cCMV) is a high priority. The guinea pig is a small-animal model for cCMV. A disabled infectious single-cycle (DISC) viral vaccine strain based on a guinea pig cytomegalovirus (GPCMV) capsid mutant was evaluated. A previous version of this vaccine did not express the gH/gL-based pentamer complex (PC) and failed to fully protect against cCMV. The PC is necessary for GPCMV epithelial cell/trophoblast tropism and congenital infection and is a potentially important neutralizing antigen. Here, we show that a second-generation PC-positive (PC+) DISC (DISCII) vaccine induces neutralizing antibodies to the PC and other glycoproteins and a cell-mediated response to pp65 (GP83). Additionally, a CRISPR/Cas9 strategy identified guinea pig platelet-derived growth factor receptor alpha (PDGFRA) to be the receptor for PC-independent infection of fibroblast cells. Importantly, PDGFRA was absent in epithelial and trophoblast cells, which were dependent upon the viral PC for infection. Virus neutralization by DISCII antibodies on epithelial and trophoblast cells was similar to that in sera from wild-type virus-infected animals and dependent in part on PC-specific antibodies. In contrast, sera from PC-negative virus-infected animals poorly neutralized virus on non-fibroblast cells. DISCII-vaccinated animals were protected against congenital infection, in contrast to a nonvaccinated group. The target organs of pups in the vaccine group were negative for wild-type virus, unlike those of pups in the control group, with GPCMV transmission being approximately 80%. Overall, the DISCII vaccine had 97% efficacy against cCMV. The complete protection provided by this PC+ DISC vaccine makes the possibility of the use of this approach against human cCMV attractive.IMPORTANCE Cytomegalovirus (CMV) is a leading cause of congenital disease in newborns, and an effective vaccine remains an elusive goal. The guinea pig is the only small-animal model for cCMV. Guinea pig cytomegalovirus (GPCMV) encodes a glycoprotein pentamer complex (PC) for entry into non-fibroblast cells, including placental trophoblasts, to enable cCMV. As with human cytomegalovirus (HCMV), GPCMV uses a specific cell receptor (PDGFRA) for fibroblast entry, but other receptors are required for non-fibroblast cells. A disabled infectious single-cycle (DISC) GPCMV vaccine strain induced an antibody immune response to the viral pentamer to enhance virus neutralization on non-fibroblast cells, and vaccinated animals were fully protected against cCMV. Inclusion of the PC as part of a vaccine design dramatically improved vaccine efficacy, and this finding underlines the importance of the immune response to the PC in contributing toward protection against cCMV. This vaccine represents an important milestone in the development of a vaccine against cCMV.
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Krmpotić A, Podlech J, Reddehase MJ, Britt WJ, Jonjić S. Role of antibodies in confining cytomegalovirus after reactivation from latency: three decades' résumé. Med Microbiol Immunol 2019; 208:415-429. [PMID: 30923898 PMCID: PMC6705608 DOI: 10.1007/s00430-019-00600-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 03/18/2019] [Indexed: 12/16/2022]
Abstract
Cytomegaloviruses (CMVs) are highly prevalent herpesviruses, characterized by strict species specificity and the ability to establish non-productive latent infection from which reactivation can occur. Reactivation of latent human CMV (HCMV) represents one of the most important clinical challenges in transplant recipients secondary to the strong immunosuppression. In addition, HCMV is the major viral cause of congenital infection with severe sequelae including brain damage. The accumulated evidence clearly shows that cellular immunity plays a major role in the control of primary CMV infection as well as establishment and maintenance of latency. However, the efficiency of antiviral antibodies in virus control, particularly in prevention of congenital infection and virus reactivation from latency in immunosuppressed hosts, is much less understood. Because of a strict species specificity of HCMV, the role of antibodies in controlling CMV disease has been addressed using murine CMV (MCMV) as a model. Here, we review and discuss the role played by the antiviral antibody response during CMV infections with emphasis on latency and reactivation not only in the MCMV model, but also in relevant clinical settings. We provide evidence to conclude that antiviral antibodies do not prevent the initiating molecular event of virus reactivation from latency but operate by preventing intra-organ spread and inter-organ dissemination of recurrent virus.
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Affiliation(s)
- Astrid Krmpotić
- Department of Histology and Embryology and Center for Proteomics, University of Rijeka, Faculty of Medicine, Braće Branchetta 20, 51000 Rijeka, Croatia
| | - Jürgen Podlech
- Institute for Virology and Research Center for Immunotherapy, University Medical Center of the Johannes Gutenberg-University Mainz, Obere Zahlbacher Strasse 67, 55131, Mainz, Germany
| | - Matthias J. Reddehase
- Institute for Virology and Research Center for Immunotherapy, University Medical Center of the Johannes Gutenberg-University Mainz, Obere Zahlbacher Strasse 67, 55131, Mainz, Germany
| | - William J. Britt
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA and Department of Pediatrics Infectious Disease, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Stipan Jonjić
- Department of Histology and Embryology and Center for Proteomics, University of Rijeka, Faculty of Medicine, Braće Branchetta 20, 51000 Rijeka, Croatia
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