1
|
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.
Collapse
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
| |
Collapse
|
2
|
He L, Taylor S, Costa C, Görzer I, Kalser J, Fu TM, Freed D, Wang D, Cui X, Hertel L, McVoy MA. Polymorphic Forms of Human Cytomegalovirus Glycoprotein O Protect against Neutralization of Fibroblast Entry by Antibodies Targeting Epitopes Defined by Glycoproteins H and L. Viruses 2022; 14:1508. [PMID: 35891489 PMCID: PMC9323020 DOI: 10.3390/v14071508] [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: 06/13/2022] [Revised: 07/05/2022] [Accepted: 07/06/2022] [Indexed: 11/16/2022] Open
Abstract
Human cytomegalovirus (CMV) utilizes different glycoproteins to enter into fibroblast and epithelial cells. A trimer of glycoproteins H, L, and O (gH/gL/gO) is required for entry into all cells, whereas a pentamer of gH/gL/UL128/UL130/UL131A is selectively required for infection of epithelial, endothelial, and some myeloid-lineage cells, but not of fibroblasts. Both complexes are of considerable interest for vaccine and immunotherapeutic development but present a conundrum: gH/gL-specific antibodies have moderate potency yet neutralize CMV entry into all cell types, whereas pentamer-specific antibodies are more potent but do not block fibroblast infection. Which cell types and neutralizing activities are important for protective efficacy in vivo remain unclear. Here, we present evidence that certain CMV strains have evolved polymorphisms in gO to evade trimer-specific neutralizing antibodies. Using luciferase-tagged variants of strain TB40/E in which the native gO is replaced by gOs from other strains, we tested the effects of gO polymorphisms on neutralization by monoclonal antibodies (mAbs) targeting four independent epitopes in gH/gL that are common to both trimer and pentamer. Neutralization of fibroblast entry by three mAbs displayed a range of potencies that depended on the gO type, a fourth mAb failed to neutralize fibroblast entry regardless of the gO type, while neutralization of epithelial cell entry by all four mAbs was potent and independent of the gO type. Thus, specific polymorphisms in gO protect the virus from mAb neutralization in the context of fibroblast but not epithelial cell entry. No influence of gO type was observed for protection against CMV hyperimmune globulin or CMV-seropositive human sera, suggesting that antibodies targeting protected gH/gL epitopes represent a minority of the polyclonal neutralizing repertoire induced by natural infection.
Collapse
Affiliation(s)
- Li He
- Department of Microbiology & Immunology, Virginia Commonwealth University, Richmond, VA 23298, USA;
| | - Scott Taylor
- School of Medicine, Virginia Commonwealth University, Richmond, VA 23298, USA; (S.T.); (C.C.)
| | - Catherine Costa
- School of Medicine, Virginia Commonwealth University, Richmond, VA 23298, USA; (S.T.); (C.C.)
| | - Irene Görzer
- Center for Virology, Medical University of Vienna, 1090 Vienna, Austria; (I.G.); (J.K.)
| | - Julia Kalser
- Center for Virology, Medical University of Vienna, 1090 Vienna, Austria; (I.G.); (J.K.)
| | - Tong-Ming Fu
- Texas Therapeutic Institute, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA;
| | - Daniel Freed
- Merck & Co., Inc., Rahway, NJ 07065, USA; (D.F.); (D.W.)
| | - Dai Wang
- Merck & Co., Inc., Rahway, NJ 07065, USA; (D.F.); (D.W.)
| | - Xiaohong Cui
- Department of Anatomy, Virginia Commonwealth University, Richmond, VA 23298, USA;
| | - Laura Hertel
- Department of Pediatrics, University of California San Francisco, Oakland, CA 94609, USA;
| | - Michael A. McVoy
- Department of Pediatrics, Virginia Commonwealth University, Richmond, VA 23298, USA
| |
Collapse
|
3
|
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.
Collapse
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
| |
Collapse
|
4
|
Congenital Human Cytomegalovirus Infection: A Narrative Review of Maternal Immune Response and Diagnosis in View of the Development of a Vaccine and Prevention of Primary and Non-Primary Infections in Pregnancy. Microorganisms 2021; 9:microorganisms9081749. [PMID: 34442828 PMCID: PMC8398868 DOI: 10.3390/microorganisms9081749] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 08/09/2021] [Accepted: 08/13/2021] [Indexed: 12/19/2022] Open
Abstract
Congenital cytomegalovirus infection (cCMV) may affect about 1% of all newborns all over the world as a result of either a primary or recurrent human cytomegalovirus (HCMV) infection. While about 90% of infants affected by cCMV are asymptomatic at birth, the remaining 10% are symptomatic often with neurodevelopmental impairment and sensorineural hearing loss. In view of identifying the best approach to vaccine prevention of cCMV, this review will examine the most important steps made in the study of the immune response to, and diagnosis of, HCMV infection. The maternal immune response and immune correlates of protection are being partially identified with a partial contribution given by our laboratory. The diagnosis of primary infection is often difficult to achieve in the first three months of pregnancy, which is the time primarily involved in virus transmission to the fetus in association with the most severe symptoms and sequelae. Prevention of cCMV is anticipated by prevention of primary infection in early pregnancy by means of different measures, such as (i) behavioral-educational measures, (ii) immunoglobulin administration, (iii) antiviral treatment with valaciclovir. However, the most promising approach to cCMV prevention appears to be the development of a non-living vaccine, including at least three viral antigens: gB, pentamer complex gHgLpUL128L, and pp65, which have been shown to be able to stimulate both the humoral and the cellular arms of the maternal immune response. Primary HCMV infection may be managed in pregnancy by counseling of the couples involved by a team of specialists that includes virologists, obstetricians, infectivologists and neonatologists.
Collapse
|
5
|
Wang HY, Valencia SM, Pfeifer SP, Jensen JD, Kowalik TF, Permar SR. Common Polymorphisms in the Glycoproteins of Human Cytomegalovirus and Associated Strain-Specific Immunity. Viruses 2021; 13:v13061106. [PMID: 34207868 PMCID: PMC8227702 DOI: 10.3390/v13061106] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 06/04/2021] [Accepted: 06/07/2021] [Indexed: 12/18/2022] Open
Abstract
Human cytomegalovirus (HCMV), one of the most prevalent viruses across the globe, is a common cause of morbidity and mortality for immunocompromised individuals. Recent clinical observations have demonstrated that mixed strain infections are common and may lead to more severe disease progression. This clinical observation illustrates the complexity of the HCMV genome and emphasizes the importance of taking a population-level view of genotypic evolution. Here we review frequently sampled polymorphisms in the glycoproteins of HCMV, comparing the variable regions, and summarizing their corresponding geographic distributions observed to date. The related strain-specific immunity, including neutralization activity and antigen-specific cellular immunity, is also discussed. Given that these glycoproteins are common targets for vaccine design and anti-viral therapies, this observed genetic variation represents an important resource for future efforts to combat HCMV infections.
Collapse
Affiliation(s)
- Hsuan-Yuan Wang
- Department of Pediatrics, Weill Cornell Medicine, New York, NY 10065, USA;
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA;
| | - Sarah M. Valencia
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA;
| | - Susanne P. Pfeifer
- Center for Evolution & Medicine, School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA; (S.P.P.); (J.D.J.)
| | - Jeffrey D. Jensen
- Center for Evolution & Medicine, School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA; (S.P.P.); (J.D.J.)
| | - Timothy F. Kowalik
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01655, USA;
| | - Sallie R. Permar
- Department of Pediatrics, Weill Cornell Medicine, New York, NY 10065, USA;
- Correspondence: ; Tel.: +1-212-746-4111
| |
Collapse
|
6
|
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.
Collapse
Affiliation(s)
- William J Britt
- Departments of Pediatrics, Microbiology, Neurobiology, University of Alabama School of Medicine, Birmingham, Alabama
| |
Collapse
|
7
|
A Replication-Defective Human Cytomegalovirus Vaccine Elicits Humoral Immune Responses Analogous to Those with Natural Infection. J Virol 2019; 93:JVI.00747-19. [PMID: 31511385 DOI: 10.1128/jvi.00747-19] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 08/21/2019] [Indexed: 12/12/2022] Open
Abstract
Human cytomegalovirus (HCMV) can cause congenital infections, which are a leading cause of childhood disabilities. Since the rate of maternal-fetal transmission is much lower in naturally infected (HCMV-seropositive) women, we hypothesize that a vaccine candidate capable of eliciting immune responses analogous to those of HCMV-seropositive subjects may confer protection against congenital HCMV. We have previously described a replication-defective virus vaccine based on strain AD169 (D. Wang, D. C. Freed, X. He, F. Li, et al., Sci Transl Med 8:362ra145, 2016, https://doi.org/10.1126/scitranslmed.aaf9387). The vaccine, named V160, has been shown to be safe and immunogenic in HCMV-seronegative human subjects, eliciting both humoral and cellular immune responses (S. P. Adler, S. E. Starr, S. A. Plotkin, S. H. Hempfling, et al., J Infect Dis 220:411-419, 2019, https://doi.org/10.1093/infdis/171.1.26). Here, we further showed that sera from V160-immunized HCMV-seronegative subjects have attributes similar in quality to those from seropositive subjects, including high-avidity antibodies to viral antigens, coverage against a panel of genetically distinct clinical isolates, and protection against viral infection in diverse types of human cells in culture. More importantly, vaccination appeared efficient in priming the human immune system, inducing memory B cells in six V160 recipients at frequencies comparable to those of three HCMV-seropositive subjects. Our results demonstrate the ability of V160 to induce robust and durable humoral memory responses to HCMV, justifying further clinical evaluation of the vaccine against congenital HCMV.IMPORTANCE In utero HCMV infection can lead to miscarriage or childhood disabilities, and an effective vaccine is urgently needed. Since children born to women who are seropositive prior to pregnancy are less likely to be affected by congenital HCMV infection, it has been hypothesized that a vaccine capable of inducing an immune response resembling the responses in HCMV-seropositive women may be effective. We previously described a replication-defective virus vaccine that has been demonstrated safe and immunogenic in HCMV-seronegative subjects. Here, we conducted additional analyses to show that the vaccine can induce antibodies with functional attributes similar to those from HCMV-seropositive subjects. Importantly, vaccination can induce long-lived memory B cells at frequencies comparable to those seen in HCMV-seropositive subjects. We conclude that this vaccine is a promising candidate that warrants further clinical evaluation for prevention of congenital HCMV.
Collapse
|
8
|
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.
Collapse
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
| |
Collapse
|
9
|
Patro ARK. Subversion of Immune Response by Human Cytomegalovirus. Front Immunol 2019; 10:1155. [PMID: 31244824 PMCID: PMC6575140 DOI: 10.3389/fimmu.2019.01155] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 05/07/2019] [Indexed: 12/14/2022] Open
Abstract
Human cytomegalovirus (HCMV) is the most common cause of congenital infections and is an important pathogen in immunocompromised individuals. Despite a robust host immune system, HCMV able to replicate, evade host defenses, establish latency for life. A significant portion of HCMV genome dedicated to encode gene products for modulation of host immune response. Growing number of HCMV gene products are being recognized to play role in immune evasion. Information on viral immune evasion mechanisms by which HCMV persists in host will be useful in devising antiviral intervention strategies and development of new vaccines. This minireview provides a brief overview of immune evasion strategy adapted by HCMV by utilizing its gene products in modulation of host immune response.
Collapse
Affiliation(s)
- A Raj Kumar Patro
- Infectious Disease Biology Group, Institute of Life Sciences (ILS), Bhubaneswar, India
| |
Collapse
|
10
|
Falk JJ, Winkelmann M, Schrezenmeier H, Stöhr D, Sinzger C, Lotfi R. A two-step screening approach for the identification of blood donors with highly and broadly neutralizing capacities against human cytomegalovirus. Transfusion 2016; 57:412-422. [PMID: 27861998 DOI: 10.1111/trf.13906] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 09/15/2016] [Accepted: 09/15/2016] [Indexed: 12/22/2022]
Abstract
BACKGROUND Hyperimmunoglobulins are frequently applied for prophylaxis and treatment of human cytomegalovirus (HCMV) infections but were only marginally effective in meta-analyses of clinical studies. This might be partially due to selection of donors rather for total anti-HCMV titers than for neutralizing capacities. To improve efficacy against HCMV infection, we aimed at developing a high-throughput screening method for identification of blood donors with highly and broadly neutralizing capacities. STUDY DESIGN AND METHODS Using a Gaussia luciferase-expressing reporter virus, 1000 HCMV immunoglobulin (Ig)G-positive plasma samples with known anti-HCMV immunoglobulin titers were analyzed regarding their neutralization titers against fibroblast and endothelial cell infection. Based on these results, a high-throughput screening was designed. Highly neutralizing plasma samples were further tested 1) by an enzyme-linked immunosorbent assay-based neutralization assay regarding efficiency against different HCMV strains and 2) for their efficiency compared to commercially available hyperimmunoglobulins. RESULTS Total anti-HCMV immunoglobulin titers did not correlate with neutralization. Mean neutralization capacities were 15-fold higher in endothelial cells compared to fibroblasts. All plasma samples neutralizing fibroblast infection were at least equally effective against infection of endothelial cells, providing the possibility to simplify our screening method by testing only fibroblasts as target cells with a plasma dilution of 1 in 400. Of the nine tested top HCMV neutralizers, four were broadly effective against different HCMV strains. All nine were significantly superior to hyperimmunoglobulins. CONCLUSION Donors with highly and broadly neutralizing capacities can be identified by a two-step high-throughput screening approach. This may provide a basis for improved antibody-based treatment or prophylaxis of HCMV infections.
Collapse
Affiliation(s)
| | - Martina Winkelmann
- University Hospital Ulm.,Institute for Clinical Transfusion Medicine and Immunogenetics Ulm, Ulm, Germany
| | - Hubert Schrezenmeier
- Institute for Transfusion Medicine, University Hospital Ulm, Ulm.,University Hospital Ulm.,Institute for Clinical Transfusion Medicine and Immunogenetics Ulm, Ulm, Germany.,German Red Cross Blood Transfusion Service, Baden-Württemberg-Hessen, Germany
| | - Dagmar Stöhr
- Institute for Virology, University Hospital Ulm, Ulm
| | | | - Ramin Lotfi
- Institute for Transfusion Medicine, University Hospital Ulm, Ulm.,University Hospital Ulm.,Institute for Clinical Transfusion Medicine and Immunogenetics Ulm, Ulm, Germany.,German Red Cross Blood Transfusion Service, Baden-Württemberg-Hessen, Germany
| |
Collapse
|
11
|
Virion Glycoprotein-Mediated Immune Evasion by Human Cytomegalovirus: a Sticky Virus Makes a Slick Getaway. Microbiol Mol Biol Rev 2016; 80:663-77. [PMID: 27307580 DOI: 10.1128/mmbr.00018-16] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The prototypic herpesvirus human cytomegalovirus (CMV) exhibits the extraordinary ability to establish latency and maintain a chronic infection throughout the life of its human host. This is even more remarkable considering the robust adaptive immune response elicited by infection and reactivation from latency. In addition to the ability of CMV to exist in a quiescent latent state, its persistence is enabled by a large repertoire of viral proteins that subvert immune defense mechanisms, such as NK cell activation and major histocompatibility complex antigen presentation, within the cell. However, dissemination outside the cell presents a unique existential challenge to the CMV virion, which is studded with antigenic glycoprotein complexes targeted by a potent neutralizing antibody response. The CMV virion envelope proteins, which are critical mediators of cell attachment and entry, possess various characteristics that can mitigate the humoral immune response and prevent viral clearance. Here we review the CMV glycoprotein complexes crucial for cell attachment and entry and propose inherent properties of these proteins involved in evading the CMV humoral immune response. These include viral glycoprotein polymorphism, epitope competition, Fc receptor-mediated endocytosis, glycan shielding, and cell-to-cell spread. The consequences of CMV virion glycoprotein-mediated immune evasion have a major impact on persistence of the virus in the population, and a comprehensive understanding of these evasion strategies will assist in designing effective CMV biologics and vaccines to limit CMV-associated disease.
Collapse
|
12
|
Arcangeletti MC, Vasile Simone R, Rodighiero I, De Conto F, Medici MC, Martorana D, Chezzi C, Calderaro A. Combined genetic variants of human cytomegalovirus envelope glycoproteins as congenital infection markers. Virol J 2015; 12:202. [PMID: 26611326 PMCID: PMC4662005 DOI: 10.1186/s12985-015-0428-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 11/16/2015] [Indexed: 11/22/2022] Open
Abstract
Background Human cytomegalovirus (HCMV) is still considered to be the main viral cause of birth defects and long-term neurological and sensory sequelae following congenital infection. Several Authors sustain a key role of HCMV envelope glycoproteins, such as gB, gN and gO - mainly involved in cell targeting, viral penetration and spread - as putative virulence factors. The genes coding for these glycoproteins possess hypervariable regions, resulting in a number of genetic variants in circulating clinical strains. Considering that the genetic polymorphisms underlying the specific differences between gB, gN and gO genotypes can influence the ability of HCMV to preferentially target specific host cells, it is very likely that they play an important role in defining HCMV infection outcome. In the present study, we analysed HCMV gB, gN and gO gene polymorphisms in viral strains isolated from paediatric patients with congenital or post-natal infection, to investigate whether specific genetic variants may be associated with congenital infection. Methods The restriction fragment polymorphisms of genes coding for HCMV gB (UL55), gN (UL73) and gO (UL74) were investigated by analysing viral DNA extracted from 40 urine samples of as many paediatric patients with congenital or post-natal HCMV infection. Randomly selected samples were subjected to DNA sequencing and phylogenetic analysis. Statistical analysis was performed using Fisher’s exact test to assess the significance of single and combined glycoprotein genotypes frequency distribution. Statistical significance was considered at a P <0.05. Results While gB genomic variants were quite homogeneously represented in both paediatric groups, the gN4 genotype significantly prevailed in congenitally infected children (89.5 %) vs post-natally infected children (47.6 %), with a predominance of the gN4c variant (47.4 %). A similar trend was observed for gO3 (52.6 % vs 19 %). Concerning genotypes association, a statistically significant (P = 0.037) gN4-gO3 combination was found specifically in the congenitally infected group. Conclusions The results indicate that the gN4 (mostly the gN4c variant) and gO3 combined genotypes could provide useful markers of congenital infection and represent suitable candidate molecules for prophylactic vaccine preparations.
Collapse
Affiliation(s)
- Maria-Cristina Arcangeletti
- Unit of Microbiology and Virology - Department of Clinical and Experimental Medicine, University of Parma, Viale A. Gramsci, 14, 43126, Parma, Italy.
| | - Rosita Vasile Simone
- Unit of Microbiology and Virology - Department of Clinical and Experimental Medicine, University of Parma, Viale A. Gramsci, 14, 43126, Parma, Italy.
| | - Isabella Rodighiero
- Unit of Microbiology and Virology - Department of Clinical and Experimental Medicine, University of Parma, Viale A. Gramsci, 14, 43126, Parma, Italy.
| | - Flora De Conto
- Unit of Microbiology and Virology - Department of Clinical and Experimental Medicine, University of Parma, Viale A. Gramsci, 14, 43126, Parma, Italy.
| | - Maria-Cristina Medici
- Unit of Microbiology and Virology - Department of Clinical and Experimental Medicine, University of Parma, Viale A. Gramsci, 14, 43126, Parma, Italy.
| | - Davide Martorana
- Unit of Molecular Genetics, University-Hospital of Parma, Parma, Italy.
| | - Carlo Chezzi
- Unit of Microbiology and Virology - Department of Clinical and Experimental Medicine, University of Parma, Viale A. Gramsci, 14, 43126, Parma, Italy.
| | - Adriana Calderaro
- Unit of Microbiology and Virology - Department of Clinical and Experimental Medicine, University of Parma, Viale A. Gramsci, 14, 43126, Parma, Italy.
| |
Collapse
|
13
|
Britt W. Controversies in the natural history of congenital human cytomegalovirus infection: the paradox of infection and disease in offspring of women with immunity prior to pregnancy. Med Microbiol Immunol 2015; 204:263-71. [DOI: 10.1007/s00430-015-0399-9] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 02/24/2015] [Indexed: 12/31/2022]
|
14
|
Lin M, Jia R, Wang M, Gao X, Zhu D, Chen S, Liu M, Yin Z, Wang Y, Chen X, Cheng A. Molecular characterization of duck enteritis virus CHv strain UL49.5 protein and its colocalization with glycoprotein M. J Vet Sci 2014; 15:389-98. [PMID: 24690604 PMCID: PMC4178140 DOI: 10.4142/jvs.2014.15.3.389] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 03/13/2014] [Indexed: 01/15/2023] Open
Abstract
The UL49.5 gene of most herpesviruses is conserved and encodes glycoprotein N. However, the UL49.5 protein of duck enteritis virus (DEV) (pUL49.5) has not been reported. In the current study, the DEV pUL49.5 gene was first subjected to molecular characterization. To verify the predicted intracellular localization of gene expression, the recombinant plasmid pEGFP-C1/pUL49.5 was constructed and used to transfect duck embryo fibroblasts. Next, the recombinant plasmid pDsRed1-N1/glycoprotein M (gM) was produced and used for co-transfection with the pEGFP-C1/pUL49.5 plasmid to determine whether DEV pUL49.5 and gM (a conserved protein in herpesviruses) colocalize. DEV pUL49.5 was thought to be an envelope glycoprotein with a signal peptide and two transmembrane domains. This protein was also predicted to localize in the cytoplasm and endoplasmic reticulum with a probability of 66.7%. Images taken by a fluorescence microscope at different time points revealed that the DEV pUL49.5 and gM proteins were both expressed in the cytoplasm. Overlap of the two different fluorescence signals appeared 12 h after transfection and continued to persist until the end of the experiment. These data indicate a possible interaction between DEV pUL49.5 and gM.
Collapse
Affiliation(s)
- Meng Lin
- Avian Disease Research Center, Sichuan Agricultural University, Chengdu 611130, China
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Molecular and biological characterization of a new isolate of guinea pig cytomegalovirus. Viruses 2014; 6:448-75. [PMID: 24473341 PMCID: PMC3939465 DOI: 10.3390/v6020448] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 01/09/2014] [Accepted: 01/09/2014] [Indexed: 12/28/2022] Open
Abstract
Development of a vaccine against congenital infection with human cytomegalovirus is complicated by the issue of re-infection, with subsequent vertical transmission, in women with pre-conception immunity to the virus. The study of experimental therapeutic prevention of re-infection would ideally be undertaken in a small animal model, such as the guinea pig cytomegalovirus (GPCMV) model, prior to human clinical trials. However, the ability to model re-infection in the GPCMV model has been limited by availability of only one strain of virus, the 22122 strain, isolated in 1957. In this report, we describe the isolation of a new GPCMV strain, the CIDMTR strain. This strain demonstrated morphological characteristics of a typical Herpesvirinae by electron microscopy. Illumina and PacBio sequencing demonstrated a genome of 232,778 nt. Novel open reading frames ORFs not found in reference strain 22122 included an additional MHC Class I homolog near the right genome terminus. The CIDMTR strain was capable of dissemination in immune compromised guinea pigs, and was found to be capable of congenital transmission in GPCMV-immune dams previously infected with salivary gland‑adapted strain 22122 virus. The availability of a new GPCMV strain should facilitate study of re-infection in this small animal model.
Collapse
|
16
|
Paradowska E, Jabłońska A, Studzińska M, Suski P, Kasztelewicz B, Zawilińska B, Wiśniewska-Ligier M, Dzierżanowska-Fangrat K, Woźniakowska-Gęsicka T, Czech-Kowalska J, Lipka B, Kornacka M, Pawlik D, Tomasik T, Kosz-Vnenchak M, Leśnikowski ZJ. Distribution of cytomegalovirus gN variants and associated clinical sequelae in infants. J Clin Virol 2013; 58:271-5. [PMID: 23806667 DOI: 10.1016/j.jcv.2013.05.024] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 04/25/2013] [Accepted: 05/28/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND Human cytomegalovirus (HCMV) is the most widespread cause of congenital infection. The effects of various viral strains and viral loads on the infection outcome have been under debate. OBJECTIVES To determine the distribution of gN variants in HCMV strains isolated from children with congenital or postnatal infection and to establish the relationship between the viral genotype, the viral load, and the sequelae. STUDY DESIGN The study population included congenitally HCMV-infected newborns and children with postnatal or unproven congenital HCMV infection. The genotyping was performed by RFLP analysis of PCR-amplified fragments, and the viral load was measured by quantitative real-time PCR. RESULTS Our results demonstrated that the HCMV genotypes gN3b, gN4b, and gN4c were prevalent in the patients examined. There were no differences in the distributions of gN genotypes in the congenitally and postnatally infected children. Multiple HCMV strains were detected in both groups of children. A significant association between the HCMV gN4 genotype and the incidence of neurological disorders was observed (p=0.045). Our results suggest that the detection of the gN2 or the gN4 genotype may be indicative of serious manifestations in children. In contrast, the gN3b and the gN1 genotypes represent less pathogenic HCMV strains. The HCMV load in urine was significantly higher in children with congenital infection compared with children with postnatal infection. No correlation was found between the viral load and the genotype. CONCLUSION Our results suggest that the gN genotype may be a virological marker of symptomatic HCMV infection in newborns.
Collapse
Affiliation(s)
- Edyta Paradowska
- Laboratory of Molecular Virology and Biological Chemistry, Institute of Medical Biology, Polish Academy of Sciences, Lodz, Poland.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|