1
|
Essa S, Safar HA, Raghupathy R. Cytokine responses to major human Cytomegalovirus antigens in mouse model. Cytokine 2024; 176:156546. [PMID: 38359558 DOI: 10.1016/j.cyto.2024.156546] [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: 09/07/2023] [Revised: 01/30/2024] [Accepted: 02/09/2024] [Indexed: 02/17/2024]
Abstract
Human cytomegalovirus (CMV) continues to be a source of severe complications in immunologically immature and immunocompromised hosts. Effective CMV vaccines that help diminish CMV disease in transplant patients and avoid congenital infection are essential. Though the exact roles of defense mechanisms are unidentified, virus-specific antibodies and cytokine responses are known to be involved in controlling CMV infections. Identifying the CMV antigens that trigger these protective immune responses will help us choose the most suitable CMV-related proteins for future vaccines. CMV envelope glycoprotein B (UL55/gB), matrix proteins (UL83/pp65, UL99/pp28, UL32/pp150), and assembly protein UL80a/pp38 are known to be targets for antiviral immune responses. We immunized mice intraperitoneally with these five CMV-related proteins for their ability to induce specific antibody responses and cytokine production in a mouse model. We observed a significant CMV-antigen-specific antibody response to UL80a/pp38 and UL83/pp65 (E/C>2.0). Mice immunized with UL80a/pp38 had significantly higher concentrations of GM-CSF, IFN-γ, IL-2, IL-4, IL-5, and IL-17A (p<0.05). Mice immunized with UL83/pp65 showed significantly higher concentrations of GM-CSF, IFN-γ, IL-2 IL-4, IL-10, IL-12, IL-17A, and TNF-α. Ratios of Th1 to Th2 cytokines revealed a Th1 cytokine bias in mice immunized with UL80a/pp38, UL83/pp65, UL32/pp150, and UL55/gB. We suggest that stimulation with multiple CMV-related proteins, which include UL80a/pp38, UL83/pp65, UL32/pp150, and UL55/gB antigens, will allow both humoral and cellular immune responses to be efficiently activated, thus serving as appropriate CMV antigens for future novel vaccines and immune-based therapeutic design.
Collapse
Affiliation(s)
- Sahar Essa
- Department of Microbiology, College of Medicine, Kuwait University, Kuwait City, Kuwait.
| | - Hussain A Safar
- OMICS Research Unit, Health Science Center, Kuwait University, Kuwait City, Kuwait.
| | - Raj Raghupathy
- Department of Microbiology, College of Medicine, Kuwait University, Kuwait City, Kuwait
| |
Collapse
|
2
|
Langley JM, Gantt S, Halperin SA, Ward B, McNeil S, Ye L, Cai Y, Smith B, Anderson DE, Mitoma FD. An enveloped virus-like particle alum-adjuvanted cytomegalovirus vaccine is safe and immunogenic: A first-in-humans Canadian Immunization Research Network (CIRN) study. Vaccine 2024; 42:713-722. [PMID: 38142214 DOI: 10.1016/j.vaccine.2023.12.019] [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: 08/14/2023] [Revised: 11/06/2023] [Accepted: 12/03/2023] [Indexed: 12/25/2023]
Abstract
INTRODUCTION Cytomegalovirus (CMV) is the most common cause of congenital infection and affected children often have permanent neurodevelopmental sequelae, including hearing loss and intellectual disability. Vaccines to prevent transmission of CMV during pregnancy are a public health priority. This first-in-humans dose-ranging, randomized, placebo-controlled, observer-blinded study evaluated the safety and immunogenicity of an enveloped virus-like particle (eVLP) vaccine expressing a modified form of the CMV glycoprotein B (gB). METHODS Healthy CMV-seronegative 18 to 40-year-olds at 3 Canadian study sites were randomized to one of 4 dose formulations (0.5 µg, 1 µg, or 2 µg gB content with alum) or 1 µg gB without alum, or placebo, given intramuscularly on days 0, 56 and 168. Outcome measures were solicited and unsolicited adverse events (AE), severe AE, gB and AD-2 epitope binding antibody titers and avidity, and neutralizing antibody (nAb) titers to CMV measured in fibroblast and epithelial cell infection assays. RESULTS Among 125 participants, the most common solicited local and general AEs were pain and headache, respectively. A dose-dependent increase in gB binding, avidity and nAb titers was observed after doses 2 and 3, with the highest titers in the alum-adjuvanted 2.0 µg dose recipients after the third dose; in the latter 24 % had responses to the broadly neutralizing AD-2 epitope. Neutralizing activity to CMV infection of fibroblasts was seen in 100 % of 2.0 µg alum-adjuvanted dose recipients, and to epithelial cell infection in 31 %. Epithelial cell nAb titers were positively correlated with higher geometric mean CMV gB binding titers. CONCLUSIONS An eVLP CMV vaccine was immunogenic in healthy CMV-seronegative adults and no safety signals were seen. Alum adjuvantation increased immunogenicity as did higher antigen content and a three dose schedule. This phase 1 trial supports further development of this eVLP CMV vaccine candidate.
Collapse
Affiliation(s)
- Joanne M Langley
- Canadian Center for Vaccinology, (Dalhousie University, IWK Health Centre and the Nova Scotia Health Authority), Canada; Departments of Pediatrics, Dalhousie University, Nova Scotia, Canada; Community Health and Epidemiology, Dalhousie University, Nova Scotia, Canada.
| | - Soren Gantt
- CHU Sainte-Justine Research Centre and the Departments of Microbiology and Pediatrics, University of Montreal (formerly at the Vaccine Evaluation Center, BC Children's Hospital Research Institute and the University of British Columbia, Vancouver BC at the time of the study), Canada
| | - Scott A Halperin
- Canadian Center for Vaccinology, (Dalhousie University, IWK Health Centre and the Nova Scotia Health Authority), Canada; Departments of Pediatrics, Dalhousie University, Nova Scotia, Canada; Microbiology and Immunology, Dalhousie University, Nova Scotia, Canada
| | - Brian Ward
- McGill University Health Centre Vaccine Study Centre, Montreal, PQ, Canada
| | - Shelly McNeil
- Canadian Center for Vaccinology, (Dalhousie University, IWK Health Centre and the Nova Scotia Health Authority), Canada; Departments of Pediatrics, Dalhousie University, Nova Scotia, Canada; Community Health and Epidemiology, Dalhousie University, Nova Scotia, Canada; Department of Medicine, Dalhousie University, Nova Scotia, Canada
| | - Lingyun Ye
- Canadian Center for Vaccinology, (Dalhousie University, IWK Health Centre and the Nova Scotia Health Authority), Canada
| | - Yun Cai
- Canadian Center for Vaccinology, (Dalhousie University, IWK Health Centre and the Nova Scotia Health Authority), Canada
| | - Bruce Smith
- Canadian Center for Vaccinology, (Dalhousie University, IWK Health Centre and the Nova Scotia Health Authority), Canada
| | | | | |
Collapse
|
3
|
Characterization of the Second Apoptosis Inhibitor Encoded by Guinea Pig Cytomegalovirus. J Virol 2022; 96:e0162222. [PMID: 36472439 PMCID: PMC9769370 DOI: 10.1128/jvi.01622-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Despite the usefulness of guinea pig cytomegalovirus (GPCMV) for studies on congenital CMV infection, its viral mechanisms for the evasion of host defense strategies have not been fully elucidated. We reported previously that GPCMV gp38.1 functions as a viral mitochondria-localized inhibitor of apoptosis-like function, and its weak activity suggested the presence of an additional inhibitory molecule(s). Here, we identified gp38.3-2, a 42-amino-acid (aa) reading frame embedded within the gp38.3 gene that encodes a positional homolog of murine CMV (MCMV) m41. Characterization of gp38.3-2 resulted in the following findings: (i) the aa sequence of gp38.3-2 shows some similarity to that of MCMV m41.1, a viral inhibitor of oligomerization of a member of Bcl-2 family protein BAK, but there is no correspondence in their predicted secondary structures; (ii) gp38.3-2, but not gp38.3, showed inhibitory activities against staurosporine-induced apoptosis; (iii) three-dimensional protein complex prediction suggests that the N-terminal α-helix of gp38.3-2 interacts with residues in the BH3 and BH1 motifs of BAK, and analysis of gp38.3-2 and BAK mutants supported this model; (iv) guinea pig fibroblast cells infected with gp38.3-2-deficient GPCMV strain Δ38.3-2 died earlier than cells infected with rescued strain r38.3-2, resulting in lower yields of Δ38.3-2; (v) Δ38.3-2 exhibited a partial but significant decrease in monocyte and macrophage infection in comparison with r38.3-2; and, however, (vi) little difference in the viral infection of guinea pigs was observed between these two strains. Therefore, we hypothesize that gp38.3-2 contributes little to the evasion of host defense mechanisms under the experimental conditions used. IMPORTANCE Although GPCMV provides a useful animal model for studies on the pathogenesis of congenital CMV infection and the development of CMV vaccine strategies, our understanding of the viral mechanisms by which it evades apoptosis of infected cells has been limited in comparison with those of murine and human CMVs. Here, we report a second GPCMV apoptosis inhibitor (42 amino acids in length) that interacts with BAK, a Bcl-2 family proapoptotic protein. Three-dimensional structural prediction indicated a unique BAK recognition by gp38.3-2 via the BH3 and BH1 motif sequences. Our findings suggest the potential development of BH3 mimetics that can regulate inhibition or induction of apoptosis based on short ~40-amino-acid peptide molecules as with GPCMV.
Collapse
|
4
|
Ligat G, Alain S, Hantz S. Towards a Prophylactic Vaccine for the Prevention of HCMV Infection. Vaccines (Basel) 2021; 9:vaccines9090968. [PMID: 34579205 PMCID: PMC8472991 DOI: 10.3390/vaccines9090968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 08/28/2021] [Indexed: 11/21/2022] Open
Affiliation(s)
- Gaëtan Ligat
- Institut de Recherche sur les Maladies Virales et Hépatiques, Université de Strasbourg, 67000 Strasbourg, France
- Correspondence:
| | - Sophie Alain
- INSERM, CHU Limoges, University of Limoges, RESINFIT, U1092, 87000 Limoges, France; (S.A.); (S.H.)
- CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses (NRCHV), 87000 Limoges, France
| | - Sébastien Hantz
- INSERM, CHU Limoges, University of Limoges, RESINFIT, U1092, 87000 Limoges, France; (S.A.); (S.H.)
- CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses (NRCHV), 87000 Limoges, France
| |
Collapse
|
5
|
Sweet C. Lessons from studies with murine cytomegalovirus that could lead to a safe live attenuated vaccine for human cytomegalovirus. Access Microbiol 2020; 2:acmi000147. [PMID: 33195979 PMCID: PMC7656186 DOI: 10.1099/acmi.0.000147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 06/03/2020] [Indexed: 11/29/2022] Open
Abstract
Studies with a murine cytomegalovirus mutant tsm5 suggested two possible approaches to producing a live attenuated human cytomegalovirus vaccine. One approach would be to use a combination of five to six mutants where an attenuating mutation in the gene of one mutant is compensated by the wild-type version in a second mutant, which in turn has a mutation in a different gene compensated by the wild-type version in a third mutant, etc. Important genes in this approach could include those involved in DNA replication. The importance of the carboxy terminase of the primase gene (M70/UL70) for its function suggested a second approach where some of the natural codons in this region could be substituted with synonymous non-preferred (minor) codons that would reduce the replication fitness of the mutant.
Collapse
Affiliation(s)
- Clive Sweet
- School of Biosciences, University of Birmingham, Birmingham, UK
| |
Collapse
|
6
|
A disclosure of hidden secrets in human cytomegalovirus: An in-silico study of identification of novel genes and their analysis for vaccine development. Meta Gene 2020. [DOI: 10.1016/j.mgene.2020.100754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
7
|
Okumura M, Matsuura-Miura M, Makino R, Miura T, Noguchi K, Majima R, Koshizuka T, Inoue N. Enhancement of guinea pig cytomegalovirus infection by two endogenously expressed components of the pentameric glycoprotein complex in epithelial cells. Sci Rep 2020; 10:8530. [PMID: 32444790 PMCID: PMC7244513 DOI: 10.1038/s41598-020-65545-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 05/06/2020] [Indexed: 11/09/2022] Open
Abstract
A better understanding of the mechanisms underlying cell tropisms and the efficiency of viral infection is critical for the development of vaccines and antiviral drugs for viral diseases. In this study, we worked on the entry mechanisms of guinea pig cytomegalovirus and found that endogenous expression of a combination of two components (GP131 and GP133) of the pentameric glycoprotein complex, which is required for non-fibroblast cell tropisms, enhanced viral infection more than 10-fold. In addition, D138A alteration in GP131 increased this enhancement by an additional 10-fold. Although differences in the efficiency of viral infection among various cell types are usually explained by differences in viral entry or traffic processes, our experimental evidences dismissed such possibilities. Instead, our findings that i) endogenous expression of GP131 and GP133 after nuclear delivery of viral DNA still enhanced infection and ii) an HDAC inhibitor overcame the need of the endogenous expression led us to hypothesize a novel mechanism that controls the efficiency of viral infection through the activation of gene expression from viral DNA delivered to the nuclei. Further studies of this unexpected phenomena warrant to understand novel but also general mechanisms for cell tropisms of viral infection and determinants that control infection efficiency.
Collapse
Affiliation(s)
- Misaki Okumura
- Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan
| | - Miku Matsuura-Miura
- Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan.,Akashi City Hall, Hyogo, Japan
| | - Reina Makino
- Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan
| | - Takuya Miura
- Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan.,JCR Pharmaceuticals Co., Ltd., Hyogo, Japan
| | - Kazuma Noguchi
- Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan
| | - Ryuichi Majima
- Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan
| | - Tetsuo Koshizuka
- Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan
| | - Naoki Inoue
- Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan.
| |
Collapse
|
8
|
Roark HK, Jenks JA, Permar SR, Schleiss MR. Animal Models of Congenital Cytomegalovirus Transmission: Implications for Vaccine Development. J Infect Dis 2020; 221:S60-S73. [PMID: 32134481 PMCID: PMC7057791 DOI: 10.1093/infdis/jiz484] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Although cytomegaloviruses (CMVs) are species-specific, the study of nonhuman CMVs in animal models can help to inform and direct research aimed at developing a human CMV (HCMV) vaccine. Because the driving force behind the development of HCMV vaccines is to prevent congenital infection, the animal model in question must be one in which vertical transmission of virus occurs to the fetus. Fortunately, two such animal models-the rhesus macaque CMV and guinea pig CMV-are characterized by congenital infection. Hence, each model can be evaluated in "proof-of-concept" studies of preconception vaccination aimed at blocking transplacental transmission. This review focuses on similarities and differences in the respective model systems, and it discusses key insights from each model germane to the study of HCMV vaccines.
Collapse
Affiliation(s)
- Hunter K Roark
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, North Carolina, USA
| | - Jennifer A Jenks
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, North Carolina, USA
| | - Sallie R Permar
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, North Carolina, USA
| | - Mark R Schleiss
- Center for Infectious Diseases and Microbiology Translational Research, University of Minnesota Medical School, Department of Pediatrics, Division of Pediatric Infectious Diseases and Immunology, Minneapolis, Minnesota, USA
| |
Collapse
|
9
|
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.
Collapse
|
10
|
Human Cytomegalovirus Compromises Development of Cerebral Organoids. J Virol 2019; 93:JVI.00957-19. [PMID: 31217239 DOI: 10.1128/jvi.00957-19] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Accepted: 06/11/2019] [Indexed: 12/24/2022] Open
Abstract
Congenital human cytomegalovirus (HCMV) infection causes a broad spectrum of central and peripheral nervous system disorders, ranging from microcephaly to hearing loss. These ramifications mandate the study of virus-host interactions in neural cells. Neural progenitor cells are permissive for lytic infection. We infected two induced pluripotent stem cell (iPSC) lines and found these more primitive cells to be susceptible to infection but not permissive. Differentiation of infected iPSCs induced de novo expression of viral antigens. iPSCs can be cultured in three dimensions to generate cerebral organoids, closely mimicking in vivo development. Mock- or HCMV-infected iPSCs were subjected to a cerebral organoid generation protocol. HCMV IE1 protein was detected in virus-infected organoids at 52 days postinfection. Absent a significant effect on organoid size, infection induced regions of necrosis and the presence of large vacuoles and cysts. Perhaps more in parallel with the subtler manifestations of HCMV-induced birth defects, infection dramatically altered neurological development of organoids, decreasing the number of developing and fully formed cortical structure sites, with associated changes in the architectural organization and depth of lamination within these structures, and manifesting aberrant expression of the neural marker β-tubulin III. Our observations parallel published descriptions of infected clinical samples, which often contain only sparse antigen-positive foci yet display areas of focal necrosis and cellular loss, delayed maturation, and abnormal cortical lamination. The parallels between pathologies present in clinical specimens and the highly tractable three-dimensional (3D) organoid system demonstrate the utility of this system in modeling host-virus interactions and HCMV-induced birth defects.IMPORTANCE Human cytomegalovirus (HCMV) is a leading cause of central nervous system birth defects, ranging from microcephaly to hearing impairment. Recent literature has provided descriptions of delayed and abnormal maturation of developing cortical tissue in infected clinical specimens. We have found that infected induced pluripotent stem cells can be differentiated into three-dimensional, viral protein-expressing cerebral organoids. Virus-infected organoids displayed dramatic alterations in development compared to those of mock-infected controls. Development in these organoids closely paralleled observations in HCMV-infected clinical samples. Infection induced regions of necrosis, the presence of larger vacuoles and cysts, changes in the architectural organization of cortical structures, aberrant expression of the neural marker β-tubulin III, and an overall reduction in numbers of cortical structure sites. We found clear parallels between the pathologies of clinical specimens and virus-infected organoids, demonstrating the utility of this highly tractable system for future investigations of HCMV-induced birth defects.
Collapse
|
11
|
Denner J. Reduction of the survival time of pig xenotransplants by porcine cytomegalovirus. Virol J 2018; 15:171. [PMID: 30409210 PMCID: PMC6225623 DOI: 10.1186/s12985-018-1088-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 10/28/2018] [Indexed: 02/06/2023] Open
Abstract
Background Xenotransplantation using pig cells, tissues and organs may help to overcome the shortage of human tissues and organs for the treatment of tissue and organ failure. Progress in the prevention of immunological rejection using genetically modified pigs and new, more effective, immunosuppression regimens will allow clinical application of xenotransplantation in near future. However, xenotransplantation may be associated with the transmission of potentially zoonotic porcine microorganisms. Until now the only xenotransplantation-associated transmission was the transmission of the porcine cytomegalovirus (PCMV) into non-human primates. PCMV caused a significant reduction of the survival time of the pig transplant. Main body of the abstract Here the available publications were analysed in order to establish the mechanism how PCMV shortened the survival time of xenotransplants. PCMV is a herpesvirus related to the human cytomegalovirus and the human herpesviruses 6 and 7. These three human herpesviruses can cause serious disease among immunocompromised human individuals, including transplant recipients. It was shown that PCMV predominantly contributes to the reduction of transplant survival in non-human primates by disruption of the coagulation system and by suppression and exhaustion of the immune system. Conclusion Although it is still unknown whether PCMV infects primate cells including human cells, indirect mechanism of the virus infection may cause reduction of the xenotransplant survival in future clinical trials and therefore PCMV has to be eliminated from donor pigs.
Collapse
Affiliation(s)
- Joachim Denner
- Robert Koch Fellow, Robert Koch Institute, Nordufer 20, 13353, Berlin, Germany.
| |
Collapse
|
12
|
Miura T, Makino R, Yamada K, Matsuura M, Okumura M, Yamada S, Watanabe S, Inoue N. Differences in the effects of mutations in GP131, a guinea pig cytomegalovirus homologue of pentameric complex component UL130, on macrophage and epithelial cell infection. J Gen Virol 2018; 99:1425-1431. [PMID: 30113297 DOI: 10.1099/jgv.0.001137] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
As congenital cytomegalovirus (CMV) infection is the major cause of developmental abnormalities in children, the development of effective vaccines is critical to public health. Recent studies have demonstrated that the pentameric complex (Pentamer) of glycoproteins, which is required for human CMV infection of endothelial and epithelial cells, could be a potent vaccine antigen. As guinea pig CMV (GPCMV) infects congenitally and encodes homologues of all Pentamer components, GPCMV models are considered to be useful for the development of vaccine strategies. Here, to clarify the precise requirement of GP131, one of the GPCMV Pentamer components, for the infection of epithelial cells and macrophages, we prepared several mutants with a charged amino acid-to-alanine alteration in GP131 and found some differences in the effects of the mutations on the infection of the two cell types, suggesting the existence of cell type-dependent recognition or function of Pentamer in GPCMV infection.
Collapse
Affiliation(s)
- Takuya Miura
- 1Laboratory of Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan.,†Present address: JCR Pharmaceuticals, Hyogo, Japan
| | - Reina Makino
- 1Laboratory of Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan
| | - Kouhei Yamada
- 1Laboratory of Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan.,‡Present address: Nagoya City Hall, Aichi, Japan
| | - Miku Matsuura
- 1Laboratory of Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan.,§Present address: Hanshin Dispensing Pharmacy, Hyogo, Japan
| | - Misaki Okumura
- 1Laboratory of Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan
| | - Souichi Yamada
- 2Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Shinji Watanabe
- 1Laboratory of Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan.,¶Present address: Eiken Chemical, Tochigi, Japan
| | - Naoki Inoue
- 1Laboratory of Microbiology and Immunology, Gifu Pharmaceutical University, Gifu, Japan
| |
Collapse
|
13
|
Advancing Our Understanding of Protective Maternal Immunity as a Guide for Development of Vaccines To Reduce Congenital Cytomegalovirus Infections. J Virol 2018; 92:JVI.00030-18. [PMID: 29343580 DOI: 10.1128/jvi.00030-18] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Human cytomegalovirus (HCMV) is the most common congenitally transmitted pathogen worldwide, impacting an estimated 1 million newborns annually. Congenital HCMV (cCMV) infection is a major global contributor to long-term neurologic deficits, including deafness, microcephaly, and neurodevelopmental delay, as well as to fetal loss and occasional infant mortality. Accordingly, design of a maternal vaccine to prevent cCMV continues to be a top public health priority. Nevertheless, we remain without a licensed vaccine. Maternal immunity provides partial protection, as the risk of vertical HCMV transmission from chronically infected mothers is reduced compared to settings in which the mother is newly infected during pregnancy. Therefore, an understanding of the maternal immune correlates of protection against cCMV is critical to informing design of an efficacious maternal vaccine. Although vaccine development is being assiduously pursued by a large number of pharmaceutical manufacturers, biotechnology organizations, and academic researchers, some pessimism has been expressed regarding the issue of whether a vaccine to protect against cCMV is possible. This pessimism is based on observations that natural immunity is not completely protective against maternal reinfection and congenital transmission. However, we assert that optimism regarding vaccine development is indeed justified, on the basis of accruing evidence of immune correlates of protection-readily achievable by vaccination-that are associated with reduced transmission of HCMV to the fetus in seronegative women. In light of the substantial burden on society conferred by cCMV infection, even a modest reduction in the occurrence of this fetal disease is an important public health goal and justifies aggressive clinical evaluation of vaccines currently in the pipeline.
Collapse
|
14
|
Antibody Cross-Reactivity between Porcine Cytomegalovirus (PCMV) and Human Herpesvirus-6 (HHV-6). Viruses 2017; 9:v9110317. [PMID: 29143761 PMCID: PMC5707524 DOI: 10.3390/v9110317] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 10/10/2017] [Accepted: 10/19/2017] [Indexed: 01/16/2023] Open
Abstract
Porcine cytomegalovirus (PCMV) infection is widely prevalent among pigs, and PCMV is one of the viruses which may be transmitted during xenotransplantation using pig cells, tissues, or organs. While human cytomegalovirus (HCMV) is a major risk factor for allotransplantation, it is still unclear whether PCMV is able to infect human cells or pose a risk for xenotransplantation. Previously, it was shown that transmission of PCMV after pig kidney to non-human primate transplantations resulted in a significantly reduced survival time of the transplanted organ. To detect PCMV, PCR-based and immunological methods were used. Screening of pigs by Western blot analyses using recombinant viral proteins revealed up to 100% of the tested animals to be infected. When the same method was applied to screen human sera for PCMV-reactive antibodies, positive Western blot results were obtained in butchers and workers in the meat industry as well as in normal blood donors. To exclude an infection of humans with PCMV, the sera were further investigated. PCMV is closely related to human herpesvirus-6 (HHV-6) and human herpesvirus-7 (HHV-7), and a sequence alignment of glycoprotein B suggests that the antibodies may cross-react with identical epitope sequences. HCMV is not related with PCMV, and no correlation between antibody reactivity against PCMV and HCMV was detected. These data indicate that antibodies against PCMV found in humans are cross-reactive antibodies against HHV-6.
Collapse
|
15
|
Pontejo SM, Murphy PM. Chemokines encoded by herpesviruses. J Leukoc Biol 2017; 102:1199-1217. [PMID: 28848041 DOI: 10.1189/jlb.4ru0417-145rr] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 07/25/2017] [Accepted: 07/26/2017] [Indexed: 12/15/2022] Open
Abstract
Viruses use diverse strategies to elude the immune system, including copying and repurposing host cytokine and cytokine receptor genes. For herpesviruses, the chemokine system of chemotactic cytokines and receptors is a common source of copied genes. Here, we review the current state of knowledge about herpesvirus-encoded chemokines and discuss their possible roles in viral pathogenesis, as well as their clinical potential as novel anti-inflammatory agents or targets for new antiviral strategies.
Collapse
Affiliation(s)
- Sergio M Pontejo
- Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Philip M Murphy
- Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| |
Collapse
|
16
|
Korver AMH, Smith RJH, Van Camp G, Schleiss MR, Bitner-Glindzicz MAK, Lustig LR, Usami SI, Boudewyns AN. Congenital hearing loss. Nat Rev Dis Primers 2017; 3:16094. [PMID: 28079113 PMCID: PMC5675031 DOI: 10.1038/nrdp.2016.94] [Citation(s) in RCA: 267] [Impact Index Per Article: 38.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Congenital hearing loss (hearing loss that is present at birth) is one of the most prevalent chronic conditions in children. In the majority of developed countries, neonatal hearing screening programmes enable early detection; early intervention will prevent delays in speech and language development and has long-lasting beneficial effects on social and emotional development and quality of life. A diagnosis of hearing loss is usually followed by a search for an underlying aetiology. Congenital hearing loss might be attributed to environmental and prenatal factors, which prevail in low-income settings; congenital infections, particularly cytomegalovirus infection, are also a common risk factor for hearing loss. Genetic causes probably account for the majority of cases in developed countries; mutations can affect any component of the hearing pathway, in particular, inner ear homeostasis (endolymph production and maintenance) and mechano-electrical transduction (the conversion of a mechanical stimulus into electrochemical activity). Once the underlying cause of hearing loss is established, it might direct therapeutic decision making and guide prevention and (genetic) counselling. Management options include specific antimicrobial therapies, surgical treatment of craniofacial abnormalities and implantable or non-implantable hearing devices. An improved understanding of the pathophysiology and molecular mechanisms that underlie hearing loss and increased awareness of recent advances in genetic testing will promote the development of new treatment and screening strategies.
Collapse
Affiliation(s)
- Anna M H Korver
- Department of Pediatrics, St Antonius Hospital, PO BOX 2500, 3430 EM Nieuwegein, The Netherlands
| | - Richard J H Smith
- Molecular Otolaryngology and Renal Research Laboratories and the Genetics PhD Program, University of Iowa, Iowa City, Iowa, USA
| | - Guy Van Camp
- Department of Medical Genetics, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Mark R Schleiss
- Division of Pediatric Infectious Diseases and Immunology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Maria A K Bitner-Glindzicz
- Genetics and Genomic Medicine Programme, University College London Great Ormond Street Institute of Child Health, London, UK
| | - Lawrence R Lustig
- Department of Otolaryngology-Head and Neck Surgery, Columbia University Medical Center, New York, New York, USA
| | - Shin-Ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
| | - An N Boudewyns
- Department of Otorhinolaryngology, Head and Neck Surgery, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| |
Collapse
|
17
|
Additive Protection against Congenital Cytomegalovirus Conferred by Combined Glycoprotein B/pp65 Vaccination Using a Lymphocytic Choriomeningitis Virus Vector. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2017; 24:CVI.00300-16. [PMID: 27795301 DOI: 10.1128/cvi.00300-16] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 10/10/2016] [Indexed: 12/12/2022]
Abstract
Subunit vaccines for prevention of congenital cytomegalovirus (CMV) infection based on glycoprotein B (gB) and pp65 are in clinical trials, but it is unclear whether simultaneous vaccination with both antigens enhances protection. We undertook evaluation of a novel bivalent vaccine based on nonreplicating lymphocytic choriomeningitis virus (rLCMV) vectors expressing a cytoplasmic tail-deleted gB [gB(dCt)] and full-length pp65 from human CMV in mice. Immunization with the gB(dCt) vector alone elicited a comparable gB-binding antibody response and a superior neutralizing response to that elicited by adjuvanted subunit gB. Immunization with the pp65 vector alone elicited robust T cell responses. Comparable immunogenicity of the combined gB(dCt) and pp65 vectors with the individual monovalent formulations was demonstrated. To demonstrate proof of principle for a bivalent rLCMV-based HCMV vaccine, the congenital guinea pig cytomegalovirus (GPCMV) infection model was used to compare rLCMV vectors encoding homologs of pp65 (GP83) and gB(dCt), alone and in combination versus Freund's adjuvanted recombinant gB. Both vectors elicited significant immune responses, and no loss of gB immunogenicity was noted with the bivalent formulation. Combined vaccination with rLCMV-vectored GPCMV gB(dCt) and pp65 (GP83) conferred better protection against maternal viremia than subunit or either monovalent rLCMV vaccine. The bivalent vaccine also was significantly more effective in reducing pup mortality than the monovalent vaccines. In summary, bivalent vaccines with rLCMV vectors expressing gB and pp65 elicited potent humoral and cellular responses and conferred protection in the GPCMV model. Further clinical trials of LCMV-vectored HCMV vaccines are warranted.
Collapse
|
18
|
Núñez-Batalla F, Jáudenes-Casaubón C, Sequí-Canet JM, Vivanco-Allende A, Zubicaray-Ugarteche J, Cabanillas-Farpón R. Aetiological Diagnosis of Child Deafness: CODEPEH Recommendations. ACTA OTORRINOLARINGOLOGICA ESPANOLA 2017. [DOI: 10.1016/j.otoeng.2016.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
19
|
Aetiological diagnosis of child deafness: CODEPEH recommendations. ACTA OTORRINOLARINGOLOGICA ESPANOLA 2016; 68:43-55. [PMID: 27644946 DOI: 10.1016/j.otorri.2016.05.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 05/19/2016] [Indexed: 12/18/2022]
Abstract
Important progress in the fields of molecular genetics (principally) and diagnostic imaging, together with the lack of a consensus protocol for guiding the diagnostic process after confirming deafness by neonatal screening, have led to this new work document drafted by the Spanish Commission for the Early Detection of Child Deafness (Spanish acronym: CODEPEH). This 2015 Recommendations Document, which is based on the most recent scientific evidence, provides guidance to professionals to support them in making decisions regarding aetiological diagnosis. Such diagnosis should be performed without delay and without impeding early intervention. Early identification of the causes of deafness offers many advantages: it prevents unnecessary trouble for the families, reduces health system expenses caused by performing different tests, and provides prognostic information that may guide therapeutic actions.
Collapse
|
20
|
|
21
|
Repair of a Mutation Disrupting the Guinea Pig Cytomegalovirus Pentameric Complex Acquired during Fibroblast Passage Restores Pathogenesis in Immune-Suppressed Guinea Pigs and in the Context of Congenital Infection. J Virol 2016; 90:7715-27. [PMID: 27307567 DOI: 10.1128/jvi.00320-16] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 06/09/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Guinea pig cytomegalovirus (GPCMV) provides a valuable model for congenital cytomegalovirus transmission. Salivary gland (SG)-passaged stocks of GPCMV are pathogenic, while tissue culture (TC) passage in fibroblasts results in attenuation. Nonpathogenic TC-derived virus N13R10 (cloned as a bacterial artificial chromosome [BAC]) has a 4-bp deletion that disrupts GP129, which encodes a subunit of the GPCMV pentameric complex (PC) believed to govern viral entry into select cell types, and GP130, an overlapping open reading frame (ORF) of unknown function. To determine if this deletion contributes to attenuation of N13R10, markerless gene transfer in Escherichia coli was used to construct virus r129, a variant of N13R10 in which the 4-bp deletion is repaired. Virions from r129 were found to contain GP129 as well as two other PC subunit proteins, GP131 and GP133, whereas these three PC subunits were absent from N13R10 virions. Replication of r129 in fibroblasts appeared unaltered compared to that of N13R10. However, following experimental challenge of immunocompromised guinea pigs, r129 induced significant weight loss, longer duration of viremia, and dramatically higher (up to 1.5 × 10(6)-fold) viral loads in blood and end organs compared to N13R10. In pregnant guinea pigs, challenge with doses of r129 virus of ≥5 × 10(6) PFU resulted in levels of maternal viremia, congenital transmission, pup viral loads, intrauterine growth restriction, and pup mortality comparable to that induced by pathogenic SG virus, although higher doses of r129 were required. These results suggest that the GP129-GP130 mutation is a significant contributor to attenuation of N13R10, likely by abrogating expression of a functional PC. IMPORTANCE Tissue culture adaptation of cytomegaloviruses rapidly selects for mutations, deletions, and rearrangements in the genome, particularly for viruses passaged in fibroblast cells. Some of these mutations are focused in the region of the genome encoding components of the pentameric complex (PC), in particular homologs of human cytomegalovirus (HCMV) proteins UL128, UL130, and UL131A. These mutations can attenuate the course of infection when the virus is reintroduced into animals for vaccine and pathogenesis studies. This study demonstrates that a deletion that arose during the process of tissue culture passage can be repaired, with subsequent restoration of pathogenicity, using BAC-based mutagenesis. Restoration of pathogenicity by repair of a frameshift mutation in GPCMV gene GP129 using this approach provides a valuable genetic platform for future studies using the guinea pig model of congenital CMV infection.
Collapse
|
22
|
Plotzki E, Keller M, Ivanusic D, Denner J. A new Western blot assay for the detection of porcine cytomegalovirus (PCMV). J Immunol Methods 2016; 437:37-42. [PMID: 27498035 DOI: 10.1016/j.jim.2016.08.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 08/02/2016] [Accepted: 08/02/2016] [Indexed: 10/21/2022]
Abstract
Porcine cytomegalovirus (PCMV) may be harmful for human recipients if xenotransplantation using pig cell, tissue or organ will be performed transmitting the virus from donor pigs to human recipients. PCMV is widespread in pigs and closely related to human pathogenic herpesviruses, however there are no data concerning infection of humans. In contrast, recently it had been shown that transplantation of organs from pigs infected with PCMV into non-human primate recipients resulted in a significant reduction of the survival time compared with the transplantation of organs from uninfected pigs. To prevent transmission of PCMV in future pig to human xenotransplantations, sensitive and specific detection methods should be used. Here a new Western blot assay using recombinant proteins corresponding to two domains of the glycoprotein gB of PCMV is described. With this assay, the presence of PCMV-specific antibodies in different pig breeds was analysed. Antibodies were detected in a high percentage of animals, in one breed up to 85%.
Collapse
Affiliation(s)
- Elena Plotzki
- HIV and Other Retroviruses, Robert Koch Institute, Nordufer 20, 13353 Berlin, Germany.
| | - Martina Keller
- HIV and Other Retroviruses, Robert Koch Institute, Nordufer 20, 13353 Berlin, Germany.
| | - Daniel Ivanusic
- HIV and Other Retroviruses, Robert Koch Institute, Nordufer 20, 13353 Berlin, Germany.
| | - Joachim Denner
- HIV and Other Retroviruses, Robert Koch Institute, Nordufer 20, 13353 Berlin, Germany.
| |
Collapse
|
23
|
Denner J. Xenotransplantation and porcine cytomegalovirus. Xenotransplantation 2016; 22:329-35. [PMID: 26381491 DOI: 10.1111/xen.12180] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 06/19/2015] [Indexed: 11/29/2022]
Abstract
Porcine microorganisms may be transmitted to the human recipient when xenotransplantation with pig cells, tissues, and organs will be performed. Most of such microorganisms can be eliminated from the donor pig by specified or designated pathogen-free production of the animals. As human cytomegalovirus causes severe transplant rejection in allotransplantation, considerable concern is warranted on the potential pathogenicity of porcine cytomegalovirus (PCMV) in the setting of xenotransplantation. On the other hand, despite having a similar name, PCMV is different from HCMV. The impact of PCMV infection on pigs is known; however, the influence of PCMV on the human transplant recipient is unclear. However, first transplantations of pig organs infected with PCMV into non-human primates were associated with a significant reduction of the survival time of the transplants. Sensitive detection methods and strategies for elimination of PCMV from donor herds are required.
Collapse
|
24
|
Russell JNH, Marsh AK, Willer DO, Ambagala APN, Dzamba M, Chan JK, Pilon R, Fournier J, Brudno M, Antony JM, Sandstrom P, Evans BJ, MacDonald KS. A novel strain of cynomolgus macaque cytomegalovirus: implications for host-virus co-evolution. BMC Genomics 2016; 17:277. [PMID: 27044312 PMCID: PMC4820910 DOI: 10.1186/s12864-016-2588-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 03/14/2016] [Indexed: 12/20/2022] Open
Abstract
Background Cytomegaloviruses belong to a large, ancient, genus of DNA viruses comprised of a wide array of species-specific strains that occur in diverse array of hosts. Methods In this study we sequenced the ~217 Kb genome of a cytomegalovirus isolated from a Mauritius cynomolgus macaque, CyCMV Mauritius, and compared it to previously sequenced cytomegaloviruses from a cynomolgus macaque of Filipino origin (CyCMV Ottawa) and two from Indian rhesus macaques (RhCMV 180.92 and RhCMV 68–1). Results Though more closely related to CyCMV Ottawa, CyCMV Mauritius is less genetically distant from both RhCMV strains than is CyCMV Ottawa. Several individual genes, including homologues of CMV genes RL11B, UL123, UL83b, UL84 and a homologue of mammalian COX-2, show a closer relationship between homologues of CyCMV Mauritius and the RhCMVs than between homologues of CyCMV Mauritius and CyCMV Ottawa. A broader phylogenetic analysis of 12 CMV strains from eight species recovers evolutionary relationships among viral strains that mirror those amongst the host species, further demonstrating co-evolution of host and virus. Conclusions Phylogenetic analyses of rhesus and cynomolgus macaque CMV genome sequences demonstrate co-speciation of the virus and host. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2588-3) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
| | - Angie K Marsh
- Department of Immunology, University of Toronto, Toronto, M5S 1A8, ON, Canada
| | - David O Willer
- Department of Medicine, University of Toronto, Toronto, M5S 1A8, ON, Canada.,Department of Microbiology, Mount Sinai Hospital, Toronto, M5G 1X5, ON, Canada
| | - Aruna P N Ambagala
- Department of Medicine, University of Toronto, Toronto, M5S 1A8, ON, Canada.,Department of Microbiology, Mount Sinai Hospital, Toronto, M5G 1X5, ON, Canada.,Present Address: Canadian Science Centre for Human and Animal Health, National Centre for Foreign Animal Disease, 1015 Arlington Street, Winnipeg, R3E 3M4, MB, Canada
| | - Misko Dzamba
- Department of Computer Science, University of Toronto, Toronto, M5S 1A8, ON, Canada
| | - Jacqueline K Chan
- Department of Medicine, University of Toronto, Toronto, M5S 1A8, ON, Canada.,Department of Microbiology, Mount Sinai Hospital, Toronto, M5G 1X5, ON, Canada
| | - Richard Pilon
- National HIV & Retrovirology Laboratories, Public Health Agency of Canada, Ottawa, K1A 0K9, ON, Canada
| | - Jocelyn Fournier
- Scientific Services Division, Health Products & Food Branch, Health Canada, Ottawa, K1A 0L2, ON, Canada
| | - Michael Brudno
- Department of Computer Science, University of Toronto, Toronto, M5S 1A8, ON, Canada
| | - Joseph M Antony
- Department of Medicine, University of Toronto, Toronto, M5S 1A8, ON, Canada.,Department of Microbiology, Mount Sinai Hospital, Toronto, M5G 1X5, ON, Canada
| | - Paul Sandstrom
- National HIV & Retrovirology Laboratories, Public Health Agency of Canada, Ottawa, K1A 0K9, ON, Canada
| | - Ben J Evans
- Biology Department, McMaster University, Life Sciences Building, 1280 Main Street West, Hamilton, L8S 4K1, ON, Canada
| | - Kelly S MacDonald
- Department of Immunology, University of Toronto, Toronto, M5S 1A8, ON, Canada. .,Department of Medicine, University of Toronto, Toronto, M5S 1A8, ON, Canada. .,Department of Microbiology, Mount Sinai Hospital, Toronto, M5G 1X5, ON, Canada. .,Section of Infectious Diseases, Department of Internal Medicine, University of Manitoba, 745 Bannatyne Ave, Winnipeg, R3E 0J9, MB, Canada. .,Present Address: University of Manitoba, Basic Medical Sciences Building, Room 501, 745 Bannatyne Ave., Winnipeg, R3E 0J9, MB, Canada.
| |
Collapse
|
25
|
Immunological methods for the detection of porcine lymphotropic herpesviruses (PLHV). J Virol Methods 2016; 233:72-7. [PMID: 27036503 DOI: 10.1016/j.jviromet.2016.02.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 02/18/2016] [Indexed: 01/14/2023]
Abstract
Porcine lymphotropic herpesviruses (PLHV-1, -2, and -3) are widespread in pigs and closely related to the human pathogenic gammaherpesviruses Epstein-Barr virus (human herpesvirus 4, HHV-4) and Kaposi sarcoma herpesvirus (HHV-8). In minipigs, PLHV-1 causes a porcine post-transplantation lymphoproliferative disorder (PTLD) after experimental transplantations. Porcine PTLD comes with clinical symptoms similar to those of human PTLD, a serious complication of solid organ and allogeneic bone marrow transplantation linked to HHV-4. Since PLHVs may be transmitted from donor pigs to the human recipient of xenotransplants (pig cells, tissues or organs), sensitive and specific methods should be developed to detect and eliminate PLHVs. Here we describe an ELISA and a Western blot assay using recombinant glycoprotein B of PLHV-1. Using both assays, the presence of specific antibodies in different pig breeds as well as in German slaughterhouse workers was analysed. Antibodies were detected in some animals, but not in human subjects.
Collapse
|
26
|
Schleiss MR. Preventing Congenital Cytomegalovirus Infection: Protection to a 'T'. Trends Microbiol 2016; 24:170-172. [PMID: 26857178 DOI: 10.1016/j.tim.2016.01.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 01/22/2016] [Indexed: 11/24/2022]
Abstract
A lack of knowledge about the correlates of maternal immunity required for protection of the placenta and fetus against congenital cytomegalovirus (CMV) transmission has complicated vaccine development. New work from Bialas and colleagues demonstrates a critical role for maternal CD4(+) T cells in controlling viremia and preventing CMV-associated fetal disease.
Collapse
Affiliation(s)
- Mark R Schleiss
- Center for Infectious Diseases and Microbiology Translational Research, Division of Pediatric Infectious Diseases and Immunology, University of Minnesota Medical School, 2001 6(th) Street SE, Minneapolis, MN 55455, USA.
| |
Collapse
|
27
|
Quinn M, Erkes DA, Snyder CM. Cytomegalovirus and immunotherapy: opportunistic pathogen, novel target for cancer and a promising vaccine vector. Immunotherapy 2016; 8:211-21. [PMID: 26786895 DOI: 10.2217/imt.15.110] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Cytomegalovirus (CMV) is a β-herpesvirus that infects most people in the world and is almost always asymptomatic in the healthy host. However, CMV persists for life, requiring continuous immune surveillance to prevent disease and thus, CMV is a frequent complication in immune compromised patients. Many groups have been exploring the potential for adoptive T-cell therapies to control CMV reactivation as well as the progression of solid tumors harboring CMV. In addition, CMV itself is being explored as a vaccine vector for eliciting potent T-cell responses. This review will discuss key features of the basic biology of CMV-specific T cells as well as highlighting unanswered questions and ongoing work in the development of T-cell-based immunotherapies to target CMV.
Collapse
Affiliation(s)
- Michael Quinn
- Department of Microbiology & Immunology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Dan A Erkes
- Department of Microbiology & Immunology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Christopher M Snyder
- Department of Microbiology & Immunology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| |
Collapse
|
28
|
Denner J, Mueller NJ. Preventing transfer of infectious agents. Int J Surg 2015; 23:306-311. [PMID: 26316157 PMCID: PMC7185644 DOI: 10.1016/j.ijsu.2015.08.032] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 07/27/2015] [Accepted: 08/04/2015] [Indexed: 12/13/2022]
Abstract
Xenotransplantation using pig cells, tissues and organs may be associated with the transfer of porcine infectious agents, which may infect the human recipient and in the worst case induce a disease (zoonosis). To prevent this, a broad screening program of the donor animals for putative zoonotic microorganisms, including bacteria, viruses, fungi and others, using sensitive and specific detection methods has to be performed. As long as it is still unknown, which microorganism represents a real risk for the recipient, experience from allotransplantation should be brought in. Due to the fact that pigs can be screened long before the date of transplantation, xenotransplantation will become eventually safer compared with allotransplantation. Screening and selection of animals free of potential zoonotic microorganisms, Caesarean section, vaccination and/or treatment with chemotherapeutics are the strategies of choice to obtain donor animals not transmitting microorganisms. In the case of porcine endogenous retroviruses (PERVs) which are integrated in the genome of all pigs and which cannot be eliminated this way, selection of animals with low virus expression and generation of genetically modified pigs suppressing PERV expressions may be performed.
Collapse
Affiliation(s)
| | - Nicolas J Mueller
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, Switzerland
| |
Collapse
|
29
|
Riese P, Trittel S, Schulze K, Guzmán CA. Rodents as pre-clinical models for predicting vaccine performance in humans. Expert Rev Vaccines 2015. [DOI: 10.1586/14760584.2015.1074043] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
| | - Stephanie Trittel
- Department of Vaccinology and Applied Microbiology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Kai Schulze
- Department of Vaccinology and Applied Microbiology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Carlos A Guzmán
- Department of Vaccinology and Applied Microbiology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| |
Collapse
|
30
|
Kumar A, Herbein G. Epigenetic regulation of human cytomegalovirus latency: an update. Epigenomics 2015; 6:533-46. [PMID: 25431945 DOI: 10.2217/epi.14.41] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Human cytomegalovirus (HCMV) is a ubiquitous virus which infects 50-90% of the population worldwide. In immunocompetent hosts, HCMV either remains unnoticed or causes mild symptoms. Upon primary infection it establishes latent infection in a few cells. However, in certain situations where immunity is either immature or compromised, HCMV may reactivate and cause mortality and morbidity. Therefore, it is utmost important to understand how HCMV establishes latent infection and associated mechanisms responsible for its reactivation. Several mechanisms are involved in the regulation of latency including chromatin remodeling by an array of enzymes and microRNAs. Here we will describe the epigenetic regulation of HCMV latency. Further we will discuss the unique HCMV latency signature and patho-physiological relevance of latent HCMV infection.
Collapse
Affiliation(s)
- Amit Kumar
- Department of Virology, University of Franche-Comte, CHRU Besançon, UPRES EA4266 Pathogens & Inflammation Department, SFR FED 4234, F-25030 Besançon, France
| | | |
Collapse
|
31
|
Vaccination with a Live Attenuated Cytomegalovirus Devoid of a Protein Kinase R Inhibitory Gene Results in Reduced Maternal Viremia and Improved Pregnancy Outcome in a Guinea Pig Congenital Infection Model. J Virol 2015; 89:9727-38. [PMID: 26178990 DOI: 10.1128/jvi.01419-15] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 07/08/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Development of a vaccine to prevent congenital cytomegalovirus infection is a major public health priority. Live vaccines attenuated through mutations targeting viral mechanisms responsible for evasion of host defense may be both safe and efficacious. Safety and vaccine efficacy were evaluated using a guinea pig cytomegalovirus (GPCMV) model. Recombinant GPCMV with a targeted deletion of gp145 (designated Δ145), a viral protein kinase R (PKR) inhibitor, was generated. Attenuation was evaluated following inoculation of 10(7) PFU of Δ145 or parental virus into guinea pigs immunosuppressed with cyclophosphamide. Efficacy was evaluated by immunizing GPCMV-naive guinea pigs twice with either 10(5) or 10(6) PFU of Δ145, establishing pregnancy, and challenging the guinea pigs with salivary gland-adapted GPCMV. The immune response, maternal viral load, pup mortality, and congenital infection rates in the vaccine and control groups were compared. Δ145 was substantially attenuated for replication in immunocompromised guinea pigs. Vaccination with Δ145 induced enzyme-linked immunosorbent assay (ELISA) and neutralizing antibody levels comparable to those achieved in natural infection. In the higher- and lower-dose vaccine groups, pup mortality was reduced to 1/24 (4%) and 4/29 (14%) pups, respectively, whereas it was 26/31 (81%) in unvaccinated control pups (P < 0.0001 for both groups versus the control group). Congenital infection occurred in 20/31 (65%) control pups but only 8/24 (33%) pups in the group vaccinated with 10(6) PFU (P < 0.05). Significant reductions in the magnitude of maternal DNAemia and pup viral load were noted in the vaccine groups compared to those in the controls. Deletion of a GPCMV genome-encoded PKR inhibitor results in a highly attenuated virus that is immunogenic and protective as a vaccine against transplacental infection. IMPORTANCE Previous attempts to develop successful immunization against cytomegalovirus have largely centered on subunit vaccination against virion proteins but have yielded disappointing results. The advent of bacterial artificial chromosome technologies has enabled engineering of recombinant cytomegaloviruses (CMVs) from which virus genome-encoded immune modulation genes have been deleted, toward the goal of developing a safe and potentially more efficacious live attenuated vaccine. Here we report the findings of studies of such a vaccine against congenital CMV infection based on a virus with a targeted deletion in gp145, a virus genome-encoded inhibitor of protein kinase R, using the guinea pig model of vertical CMV transmission. The deletion virus was attenuated for dissemination in immunocompromised guinea pigs but elicited ELISA and neutralizing responses. The vaccine conferred protection against maternal DNAemia and congenital transmission and resulted in reduced viral loads in newborn guinea pigs. These results provide support for future studies of attenuated CMV vaccines.
Collapse
|
32
|
Swanson EC, Gillis P, Hernandez-Alvarado N, Fernández-Alarcón C, Schmit M, Zabeli JC, Wussow F, Diamond DJ, Schleiss MR. Comparison of monovalent glycoprotein B with bivalent gB/pp65 (GP83) vaccine for congenital cytomegalovirus infection in a guinea pig model: Inclusion of GP83 reduces gB antibody response but both vaccine approaches provide equivalent protection against pup mortality. Vaccine 2015; 33:4013-8. [PMID: 26079615 DOI: 10.1016/j.vaccine.2015.06.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 05/26/2015] [Accepted: 06/02/2015] [Indexed: 01/06/2023]
Abstract
Cytomegalovirus (CMV) subunit vaccine candidates include glycoprotein B (gB), and phosphoprotein ppUL83 (pp65). Using a guinea pig cytomegalovirus (GPCMV) model, this study compared immunogenicity, pregnancy outcome, and congenital viral infection following pre-pregnancy immunization with a three-dose series of modified vaccinia virus Ankara (MVA)-vectored vaccines consisting either of gB administered alone, or simultaneously with a pp65 homolog (GP83)-expressing vaccine. Vaccinated and control dams were challenged at midgestation with salivary gland-adapted GPCMV. Comparisons included ELISA and neutralizing antibody responses, maternal viral load, pup mortality, and congenital infection rates. Strikingly, ELISA and neutralization titers were significantly lower in the gB/GP83 combined vaccine group than in the gB group. However, both vaccines protected against pup mortality (63.2% in controls vs. 11.4% and 13.9% in gB and gB/GP83 combination groups, respectively; p<0.0001). Reductions in pup viral load were noted for both vaccine groups compared to control, but preconception vaccination resulted in a significant reduction in GPCMV transmission only in the monovalent gB group (26/44, 59% v. 27/34, 79% in controls; p<0.05). We conclude that, using the MVA platform, the addition of GP83 to a gB subunit vaccine interferes with antibody responses and diminishes protection against congenital GPCMV infection, but does not decrease protection against pup mortality.
Collapse
Affiliation(s)
- Elizabeth C Swanson
- University of Minnesota Medical School, Department of Pediatrics, Center for Infectious Diseases and Microbiology Translational Research, 2001 6th Street SE, Minneapolis, MN 55455, United States
| | - Pete Gillis
- University of Minnesota Medical School, Department of Pediatrics, Center for Infectious Diseases and Microbiology Translational Research, 2001 6th Street SE, Minneapolis, MN 55455, United States
| | - Nelmary Hernandez-Alvarado
- University of Minnesota Medical School, Department of Pediatrics, Center for Infectious Diseases and Microbiology Translational Research, 2001 6th Street SE, Minneapolis, MN 55455, United States
| | - Claudia Fernández-Alarcón
- University of Minnesota Medical School, Department of Pediatrics, Center for Infectious Diseases and Microbiology Translational Research, 2001 6th Street SE, Minneapolis, MN 55455, United States
| | - Megan Schmit
- University of Minnesota Medical School, Department of Pediatrics, Center for Infectious Diseases and Microbiology Translational Research, 2001 6th Street SE, Minneapolis, MN 55455, United States
| | - Jason C Zabeli
- University of Minnesota Medical School, Department of Pediatrics, Center for Infectious Diseases and Microbiology Translational Research, 2001 6th Street SE, Minneapolis, MN 55455, United States
| | - Felix Wussow
- Department of Virology, Beckman Research Institute of City of Hope, 1500 E. Duarte Rd, Duarte, CA 91010, United States
| | - Don J Diamond
- Department of Virology, Beckman Research Institute of City of Hope, 1500 E. Duarte Rd, Duarte, CA 91010, United States
| | - Mark R Schleiss
- University of Minnesota Medical School, Department of Pediatrics, Center for Infectious Diseases and Microbiology Translational Research, 2001 6th Street SE, Minneapolis, MN 55455, United States.
| |
Collapse
|
33
|
Plotzki E, Wolf-van Buerck L, Knauf Y, Becker T, Maetz-Rensing K, Schuster M, Baehr A, Klymiuk N, Wolf E, Seissler J, Denner J. Virus safety of islet cell transplantation from transgenic pigs to marmosets. Virus Res 2015; 204:95-102. [PMID: 25956348 DOI: 10.1016/j.virusres.2015.04.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 04/15/2015] [Accepted: 04/16/2015] [Indexed: 12/16/2022]
Abstract
Transplantation of pig islet cells for the treatment of diabetes may be a more effective approach compared with the application of insulin. However, before introduction into the clinic, efficacy and safety of this treatment have to be shown. Non-human primate models may be used for this, despite the fact that they are characterised by several limitations. Here we investigate the prevalence of porcine endogenous retroviruses (PERVs), which are present in the genome of all pigs and which may infect human cells, as well as of porcine herpes viruses in donor pigs and their potential transmission to non-human primate recipients. Despite the fact that all three subtypes of PERV were present in all and porcine cytomegalovirus (PCMV) was found in some of the pigs, neither PERVs nor PCMV were found in the recipient animals under the experimental conditions applied. Porcine lymphotropic herpes viruses (PLHV) were not found in the donor pigs, hepatitis E virus (HEV) was not found in the recipients.
Collapse
Affiliation(s)
- Elena Plotzki
- Robert Koch Institute, HIV and Other Retroviruses, Nordufer 20, 13353 Berlin, Germany.
| | - Lelia Wolf-van Buerck
- Medizinische Klinik und Poliklinik IV, Diabeteszentrum, Ludwig-Maximilians-Universität, München, Ziemssenstraße 1, 80336 München, Germany.
| | - Yvonne Knauf
- German Primate Center, Leibniz-Institute, Pathology Unit, Kellnerweg 4, 37077 Göttingen, Germany.
| | - Tamara Becker
- German Primate Center, Leibniz-Institute, Pathology Unit, Kellnerweg 4, 37077 Göttingen, Germany.
| | - Kerstin Maetz-Rensing
- German Primate Center, Leibniz-Institute, Pathology Unit, Kellnerweg 4, 37077 Göttingen, Germany.
| | - Marion Schuster
- Medizinische Klinik und Poliklinik IV, Diabeteszentrum, Ludwig-Maximilians-Universität, München, Ziemssenstraße 1, 80336 München, Germany.
| | - Andrea Baehr
- Chair for Molecular Animal Breeding and Biotechnology and Laboratory for Functional Genome Analysis (LAFUGA), Gene Center, Ludwig-Maximilians-Universität München, Hackerstraße 27, 85764 Oberschleißheim, Germany.
| | - Nikolai Klymiuk
- Chair for Molecular Animal Breeding and Biotechnology and Laboratory for Functional Genome Analysis (LAFUGA), Gene Center, Ludwig-Maximilians-Universität München, Hackerstraße 27, 85764 Oberschleißheim, Germany.
| | - Eckhard Wolf
- Chair for Molecular Animal Breeding and Biotechnology and Laboratory for Functional Genome Analysis (LAFUGA), Gene Center, Ludwig-Maximilians-Universität München, Hackerstraße 27, 85764 Oberschleißheim, Germany.
| | - Jochen Seissler
- Medizinische Klinik und Poliklinik IV, Diabeteszentrum, Ludwig-Maximilians-Universität, München, Ziemssenstraße 1, 80336 München, Germany.
| | - Joachim Denner
- Robert Koch Institute, HIV and Other Retroviruses, Nordufer 20, 13353 Berlin, Germany.
| |
Collapse
|
34
|
Gaska JM, Ploss A. Study of viral pathogenesis in humanized mice. Curr Opin Virol 2015; 11:14-20. [PMID: 25618248 PMCID: PMC4456257 DOI: 10.1016/j.coviro.2015.01.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 01/06/2015] [Indexed: 12/28/2022]
Abstract
Many of the viral pathogens that cause infectious diseases in humans have a highly restricted species tropism, making the study of their pathogenesis and the development of clinical therapies difficult. The improvement of humanized mouse models over the past 30 years has greatly facilitated researchers' abilities to study host responses to viral infections in a cost effective and ethical manner. From HIV to hepatotropic viruses to Middle East Respiratory Syndrome coronavirus, humanized mice have led to the identification of factors crucial to the viral life cycle, served as an outlet for testing candidate therapies, and improved our abilities to analyze human immune responses to infection. In tackling both new and old viruses as they emerge, humanized mice will continue to be an indispensable tool.
Collapse
Affiliation(s)
- Jenna M Gaska
- Department of Molecular Biology, Princeton University, 110 Lewis Thomas Laboratory, Washington Road, Princeton, NJ 08544-1014, USA
| | - Alexander Ploss
- Department of Molecular Biology, Princeton University, 110 Lewis Thomas Laboratory, Washington Road, Princeton, NJ 08544-1014, USA.
| |
Collapse
|
35
|
Farrell H. Animal models of human cytomegalovirus congenital infection. MICROBIOLOGY AUSTRALIA 2015. [DOI: 10.1071/ma15068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Human cytomegalovirus (HCMV) infection is highly species-specific, which means that it is unable to productively infect laboratory animals. Despite this caveat, studies of animal CMV counterparts in their natural hosts have revealed significant correlations with observed neuropathological effects of congenital HCMV infection and have improved our understanding of host responses to vaccination. The biological relatedness between human and animal CMVs has been confirmed by phylogenetic analyses; the conservation of ‘core' genes that are essential for virus replication as well as genes that contribute similar mechanisms for virus persistence in their respective host species. The common animal models of HCMV congenital infection include Rhesus CMV (RhCMV), guinea-pig CMV (GPCMV) and mouse CMV (MCMV). Whilst animal models of CMV do not fully recapitulate HCMV infection, they each offer specific advantages in understanding HCMV congenital/perinatal infection (summarised in Table 1).
Collapse
|
36
|
Wiegers AK, Sticht H, Winkler TH, Britt WJ, Mach M. Identification of a neutralizing epitope within antigenic domain 5 of glycoprotein B of human cytomegalovirus. J Virol 2015; 89:361-72. [PMID: 25320309 PMCID: PMC4301166 DOI: 10.1128/jvi.02393-14] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 10/07/2014] [Indexed: 01/19/2023] Open
Abstract
UNLABELLED Human cytomegalovirus (HCMV) is an important, ubiquitous pathogen that causes severe clinical disease in immunocompromised individuals, such as organ transplant recipients and infants infected in utero. The envelope glycoprotein B (gB) of HCMV is a major antigen for the induction of virus-neutralizing antibodies. We have begun to define target structures within gB that are recognized by virus-neutralizing antibodies. Antigenic domain 5 (AD-5) of gB has been identified as an important target for neutralizing antibodies in studies using human monoclonal antibodies (MAbs). Anti-AD-5 MAbs share a target site on gB, despite originating from different, healthy, HCMV-infected donors. Mutational analysis of AD-5 identified tyrosine 280 in combination with other surface-exposed residues (the YNND epitope) as critical for antibody binding. The YNND epitope is strictly conserved among different HCMV strains. Recombinant viruses carrying YNND mutations in AD-5 were resistant to virus-neutralizing MAbs. Competition enzyme-linked immunosorbent assays (ELISAs) with human HCMV-convalescent-phase sera from unselected donors confirmed the conserved antibody response for the YNND epitope in HCMV-infected individuals and, because a significant fraction of the gB AD-5 response was directed against the YNND epitope, further argued that this epitope is a major target of anti-AD-5 antibody responses. In addition, affinity-purified polyclonal anti-AD-5 antibodies prepared from individual sera showed reactivity to AD-5 and neutralization activity toward gB mutant viruses that were similar to those of AD-5-specific MAbs. Taken together, our data indicate that the YNND epitope represents an important target for anti-gB antibody responses as well as for anti-AD-5 virus-neutralizing antibodies. IMPORTANCE HCMV is a major global health concern, and a vaccine to prevent HCMV disease is a widely recognized medical need. Glycoprotein B of HCMV is an important target for neutralizing antibodies and hence an interesting molecule for intervention strategies, e.g., vaccination. Mapping the target structures of neutralizing antibodies induced by naturally occurring HCMV infection can aid in defining the properties required for a protective capacity of vaccine antigens. The data presented here extend our knowledge of neutralizing epitopes within gB to include AD-5. Collectively, our data will contribute to optimal vaccine design and development of antibody-based therapies.
Collapse
Affiliation(s)
- Anna-Katharina Wiegers
- Institut für Klinische und Molekulare Virologie, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Heinrich Sticht
- Institut für Biochemie, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Thomas H Winkler
- Nikolaus-Fiebiger-Zentrum für Molekulare Medizin, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
| | - William J Britt
- Department of Pediatrics, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Michael Mach
- Institut für Klinische und Molekulare Virologie, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
| |
Collapse
|
37
|
McCormick AL, Mocarski ES. The immunological underpinnings of vaccinations to prevent cytomegalovirus disease. Cell Mol Immunol 2014; 12:170-9. [PMID: 25544503 DOI: 10.1038/cmi.2014.120] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 11/10/2014] [Indexed: 01/03/2023] Open
Abstract
A universal cytomegalovirus (CMV) vaccination promises to reduce the burden of the developmental damage that afflicts up to 0.5% of live births worldwide. An effective vaccination that prevents transplacental transmission would reduce CMV congenital disease and CMV-associated still births and leave populations less susceptible to opportunistic CMV disease. Thus, a vaccination against this virus has long been recognized for the potential of enormous health-care savings because congenital damage is life-long and existing anti-viral options are limited. Vaccine researchers, industry leaders, and regulatory representatives have discussed the challenges posed by clinical efficacy trials that would lead to a universal CMV vaccine, reviewing the links between infection and disease, and identifying settings where disrupting viral transmission might provide a surrogate endpoint for disease prevention. Reducing the complexity of such trials would facilitate vaccine development. Children and adolescents are the targets for universal vaccination, with the expectation of protecting the offspring of immunized women. Given that a majority of females worldwide experience CMV infection during childhood, a universal vaccine must boost natural immunity and reduce transmission due to reactivation and re-infection as well as primary infection during pregnancy. Although current vaccine strategies recognize the value of humoral and cellular immunity, the precise mechanisms that act at the placental interface remain elusive. Immunity resulting from natural infection appears to limit rather than prevent reactivation of latent viruses and susceptibility to re-infection, leaving a challenge for universal vaccination to improve upon natural immunity levels. Despite these hurdles, early phase clinical trials have achieved primary end points in CMV seronegative subjects. Efficacy studies must be expanded to mixed populations of CMV-naive and naturally infected subjects to understand the overall efficacy and potential. Together with CMV vaccine candidates currently in clinical development, additional promising preclinical strategies continue to come forward; however, these face limitations due to the insufficient understanding of host defense mechanisms that prevent transmission, as well as the age-old challenges of reaching the appropriate threshold of immunogenicity, efficacy, durability and potency. This review focuses on the current understanding of natural and CMV vaccine-induced protective immunity.
Collapse
Affiliation(s)
- A Louise McCormick
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University, Atlanta, GA, USA
| | - Edward S Mocarski
- Department of Microbiology and Immunology and Emory Vaccine Center, Emory University, Atlanta, GA, USA
| |
Collapse
|