1
|
Hilt ZT, Charles W, Cheng KE, Tabilas C, Steinhilber M, Wesnak SP, Smith NL, Schaffer CB, Rudd BD. Cutting Edge: CCR9 Promotes CD8+ T Cell Recruitment to the Brain during Congenital Cytomegalovirus Infection. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 209:2281-2286. [PMID: 36469843 PMCID: PMC9886274 DOI: 10.4049/jimmunol.2200578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 10/20/2022] [Indexed: 01/04/2023]
Abstract
CD8+ T lymphocytes infiltrate the brain during congenital CMV infection and promote viral clearance. However, the mechanisms by which CD8+ T cells are recruited to the brain remain unclear. Using a mouse model of congenital CMV, we found a gut-homing chemokine receptor (CCR9) was preferentially expressed in CD8+ T cells localized in the brain postinfection. In the absence of CCR9 or CCL25 (CCR9's ligand) expression, CD8+ T cells failed to migrate to key sites of infection in the brain and protect the host from severe forms of disease. Interestingly, we found that expression of CCR9 on CD8+ T cells was also responsible for spatial temporal positioning of T cells in the brain. Collectively, our data demonstrate that the CMV-infected brain uses a similar mechanism for CD8+ T cell homing as the small intestine.
Collapse
Affiliation(s)
- Zachary T. Hilt
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
| | - Wisler Charles
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
| | - Katarina E. Cheng
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
| | - Cybelle Tabilas
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
| | - Megan Steinhilber
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
| | - Samantha P. Wesnak
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
| | - Norah L. Smith
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
| | - Chris B. Schaffer
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | - Brian D. Rudd
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
| |
Collapse
|
2
|
Braxton AM, Chalmin AL, Najarro KM, Brockhurst JK, Johnson KT, Lyons CE, Daly B, Cryer CG, Vijay S, Cyphers G, Guerrero-Martin SM, Aston SA, McGee K, Su YP, Arav-Boger R, Metcalf Pate KA. Platelet-endothelial associations may promote cytomegalovirus replication in the salivary gland in mice. Platelets 2020; 31:860-868. [PMID: 31726921 PMCID: PMC7220825 DOI: 10.1080/09537104.2019.1689383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 10/24/2019] [Accepted: 10/31/2019] [Indexed: 10/25/2022]
Abstract
Platelet decline is a feature of many acute viral infections, including cytomegalovirus (CMV) infection in humans and mice. Platelet sequestration in association with other cells, including endothelium and circulating leukocytes, can contribute to this decline and influence the immune response to and pathogenesis of viral infection. We sought to determine if platelet-endothelial associations (PEAs) contribute to platelet decline during acute murine CMV (mCMV) infection, and if these associations affect viral load and production. Male BALB/c mice were infected with mCMV (Smith strain), euthanized at timepoints throughout acute infection and compared to uninfected controls. An increase in PEA formation was confirmed in the salivary gland at all post-inoculation timepoints using immunohistochemistry for CD41+ platelets co-localizing with CD34+ vessels. Platelet depletion did not change amount of viral DNA or timecourse of infection, as measured by qPCR. However, platelet depletion reduced viral titer of mCMV in the salivary glands while undepleted controls demonstrated robust replication in the tissue by plaque assay. Thus, platelet associations with endothelium may enhance the ability of mCMV to replicate within the salivary gland. Further work is needed to determine the mechanisms behind this effect and if pharmacologic inhibition of PEAs may reduce CMV production in acutely infected patients.
Collapse
Affiliation(s)
- Alicia M. Braxton
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Alyssa L. Chalmin
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Kevin M. Najarro
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Jacqueline K. Brockhurst
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
- University of Pennsylvania School of Veterinary Medicine, Philadelphia, USA
| | - Karl T. Johnson
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Claire E. Lyons
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Brenna Daly
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
- Cummings School of Veterinary Medicine, Tufts University, North Grafton, USA
| | - Catherine G. Cryer
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
- University of Pennsylvania School of Veterinary Medicine, Philadelphia, USA
| | - Shefali Vijay
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Griffin Cyphers
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Selena M. Guerrero-Martin
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - S. Andrew Aston
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
- Department of Psychiatry of Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Kirstin McGee
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Yu-Pin Su
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Ravit Arav-Boger
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, USA
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, USA
| | - Kelly A. Metcalf Pate
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, USA
| |
Collapse
|
3
|
The Human Cytomegalovirus Chemokine vCXCL-1 Modulates Normal Dissemination Kinetics of Murine Cytomegalovirus In Vivo. mBio 2019; 10:mBio.01289-19. [PMID: 31239384 PMCID: PMC6593410 DOI: 10.1128/mbio.01289-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
An adequate in vivo analysis of HCMV’s viral chemokine vCXCL-1 has been lacking. Here we generate recombinant MCMVs expressing vCXCL-1 to study vCXCL-1 function in vivo using MCMV as a surrogate. We demonstrate that vCXCL-1 increases MCMV dissemination kinetics for both primary and secondary dissemination. Additionally, we provide evidence, that the murine neutrophil is largely a bystander in the mouse’s response to vCXCL-1. We confirm the hypothesis that vCXCL-1 is a HCMV virulence factor. Infection of severely immunocompromised mice with MCMVs expressing vCXCL-1 was lethal in more than 50% of infected animals, while all animals infected with parental virus survived during a 12-day period. This work provides needed insights into vCXCL-1 function in vivo. Human cytomegalovirus (HCMV) is a betaherpesvirus that is a significant pathogen within newborn and immunocompromised populations. Morbidity associated with HCMV infection is the consequence of viral dissemination. HCMV has evolved to manipulate the host immune system to enhance viral dissemination and ensure long-term survival within the host. The immunomodulatory protein vCXCL-1, a viral chemokine functioning primarily through the CXCR2 chemokine receptor, is hypothesized to attract CXCR2+ neutrophils to infection sites, aiding viral dissemination. Neutrophils harbor HCMV in vivo; however, the interaction between vCXCL-1 and the neutrophil has not been evaluated in vivo. Using the mouse model and mouse cytomegalovirus (MCMV) infection, we show that murine neutrophils harbor and transfer infectious MCMV and that virus replication initiates within this cell type. Utilizing recombinant MCMVs expressing vCXCL-1 from the HCMV strain (Toledo), we demonstrated that vCXCL-1 significantly enhances MCMV dissemination kinetics. Through cellular depletion experiments, we observe that neutrophils impact dissemination but that overall dissemination is largely neutrophil independent. This work adds neutrophils to the list of innate cells (i.e., dendritic and macrophages/monocytes) that contribute to MCMV dissemination but refutes the hypothesis that neutrophils are the primary cell responding to vCXCL-1.
Collapse
|
4
|
Diagnosis and Management of CMV Endotheliitis. CURRENT OPHTHALMOLOGY REPORTS 2019. [DOI: 10.1007/s40135-019-00205-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
5
|
Alston CI, Dix RD. SOCS and Herpesviruses, With Emphasis on Cytomegalovirus Retinitis. Front Immunol 2019; 10:732. [PMID: 31031749 PMCID: PMC6470272 DOI: 10.3389/fimmu.2019.00732] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 03/19/2019] [Indexed: 01/08/2023] Open
Abstract
Suppressor of cytokine signaling (SOCS) proteins provide selective negative feedback to prevent pathogeneses caused by overstimulation of the immune system. Of the eight known SOCS proteins, SOCS1 and SOCS3 are the best studied, and systemic deletion of either gene causes early lethality in mice. Many viruses, including herpesviruses such as herpes simplex virus and cytomegalovirus, can manipulate expression of these host proteins, with overstimulation of SOCS1 and/or SOCS3 putatively facilitating viral evasion of immune surveillance, and SOCS suppression generally exacerbating immunopathogenesis. This is particularly poignant within the eye, which contains a diverse assortment of specialized cell types working together in a tightly controlled microenvironment of immune privilege. When the immune privilege of the ocular compartment fails, inflammation causing severe immunopathogenesis and permanent, sight-threatening damage may occur, as in the case of AIDS-related human cytomegalovirus (HCMV) retinitis. Herein we review how SOCS1 and SOCS3 impact the virologic, immunologic, and/or pathologic outcomes of herpesvirus infection with particular emphasis on retinitis caused by HCMV or its mouse model experimental counterpart, murine cytomegalovirus (MCMV). The accumulated data suggests that SOCS1 and/or SOCS3 can differentially affect the severity of viral diseases in a highly cell-type-specific manner, reflecting the diversity and complexity of herpesvirus infection and the ocular compartment.
Collapse
Affiliation(s)
- Christine I Alston
- Department of Biology, Viral Immunology Center, Georgia State University, Atlanta, GA, United States.,Department of Ophthalmology, Emory University School of Medicine, Atlanta, GA, United States
| | - Richard D Dix
- Department of Biology, Viral Immunology Center, Georgia State University, Atlanta, GA, United States.,Department of Ophthalmology, Emory University School of Medicine, Atlanta, GA, United States
| |
Collapse
|
6
|
Suppressor of Cytokine Signaling 1 (SOCS1) and SOCS3 Are Stimulated within the Eye during Experimental Murine Cytomegalovirus Retinitis in Mice with Retrovirus-Induced Immunosuppression. J Virol 2018; 92:JVI.00526-18. [PMID: 29976680 DOI: 10.1128/jvi.00526-18] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 06/15/2018] [Indexed: 11/20/2022] Open
Abstract
AIDS-related human cytomegalovirus retinitis remains the leading cause of blindness among untreated HIV/AIDS patients worldwide. To study mechanisms of this disease, we used a clinically relevant animal model of murine cytomegalovirus (MCMV) retinitis with retrovirus-induced murine AIDS (MAIDS) that mimics the progression of AIDS in humans. We found in this model that MCMV infection significantly stimulates ocular suppressor of cytokine signaling 1 (SOCS1) and SOCS3, host proteins which hinder immune-related signaling by cytokines, including antiviral type I and type II interferons. The present study demonstrates that in the absence of retinal disease, systemic MCMV infection of mice without MAIDS, but not in mice with MAIDS, leads to mild stimulation of splenic SOCS1 mRNA. In sharp contrast, when MCMV is directly inoculated into the eyes of retinitis-susceptible MAIDS mice, high levels of intraocular SOCS1 and SOCS3 mRNA and protein are produced which are associated with significant intraocular upregulation of gamma interferon (IFN-γ) and interleukin-6 (IL-6) mRNA expression. We also show that infiltrating macrophages, granulocytes, and resident retinal cells are sources of intraocular SOCS1 and SOCS3 protein production during development of MAIDS-related MCMV retinitis, and SOCS1 and SOCS3 mRNA transcripts are detected in retinal areas histologically characteristic of MCMV retinitis. Furthermore, SOCS1 and SOCS3 are found in both MCMV-infected cells and uninfected cells, suggesting that these SOCS proteins are stimulated via a bystander mechanism during MCMV retinitis. Taken together, our findings suggest a role for MCMV-related stimulation of SOCS1 and SOCS3 in the progression of retinal disease during ocular, but not systemic, MCMV infection.IMPORTANCE Cytomegalovirus infection frequently causes blindness in untreated HIV/AIDS patients. This virus manipulates host cells to dysregulate immune functions and drive disease. Here, we use an animal model of this disease to demonstrate that cytomegalovirus infection within eyes during retinitis causes massive upregulation of immunosuppressive host proteins called SOCS. As viral overexpression of SOCS proteins exacerbates infection with other viruses, they may also enhance cytomegalovirus infection. Alternatively, the immunosuppressive effect of SOCS proteins may be protective against immunopathology during cytomegalovirus retinitis, and in such a case SOCS mimetics or overexpression treatment strategies might be used to combat this disease. The results of this work therefore provide crucial basic knowledge that contributes to our understanding of the mechanisms of AIDS-related cytomegalovirus retinitis and, together with future studies, may contribute to the development of novel therapeutic targets that could improve the treatment or management of this sight-threatening disease.
Collapse
|
7
|
Jackson JW, Sparer T. There Is Always Another Way! Cytomegalovirus' Multifaceted Dissemination Schemes. Viruses 2018; 10:v10070383. [PMID: 30037007 PMCID: PMC6071125 DOI: 10.3390/v10070383] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 07/17/2018] [Accepted: 07/18/2018] [Indexed: 12/12/2022] Open
Abstract
Human cytomegalovirus (HCMV) is a β-herpes virus that is a significant pathogen within immune compromised populations. HCMV morbidity is induced through viral dissemination and inflammation. Typically, viral dissemination is thought to follow Fenner's hypothesis where virus replicates at the site of infection, followed by replication in the draining lymph nodes, and eventually replicating within blood filtering organs. Although CMVs somewhat follow Fenner's hypothesis, they deviate from it by spreading primarily through innate immune cells as opposed to cell-free virus. Also, in vivo CMVs infect new cells via cell-to-cell spread and disseminate directly to secondary organs through novel mechanisms. We review the historic and recent literature pointing to CMV's direct dissemination to secondary organs and the genes that it has evolved for increasing its ability to disseminate. We also highlight aspects of CMV infection for studying viral dissemination when using in vivo animal models.
Collapse
Affiliation(s)
- Joseph W Jackson
- Department of Microbiology, University of Tennessee Knoxville, Knoxville, TN 37996, USA.
| | - Tim Sparer
- Department of Microbiology, University of Tennessee Knoxville, Knoxville, TN 37996, USA.
| |
Collapse
|
8
|
Čížková D, Baird SJE, Těšíková J, Voigt S, Ľudovít Ď, Piálek J, Goüy de Bellocq J. Host subspecific viral strains in European house mice: Murine cytomegalovirus in the Eastern (Mus musculus musculus) and Western house mouse (Mus musculus domesticus). Virology 2018; 521:92-98. [PMID: 29894896 DOI: 10.1016/j.virol.2018.05.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 05/27/2018] [Accepted: 05/28/2018] [Indexed: 01/14/2023]
Abstract
Murine cytomegalovirus (MCMV) has been reported from house mice (Mus musculus) worldwide, but only recently from Eastern house mice (M. m. musculus), of particular interest because they form a semi-permeable species barrier in Europe with Western house mice, M. m. domesticus. Here we report genome sequences of EastMCMV (from Eastern mice), and set these in the context of MCMV genomes from genus Mus hosts. We show EastMCMV and WestMCMV are genetically distinct. Phylogeny splitting analyses show a genome wide (94%) pattern consistent with no West-East introgression, the major exception (3.8%) being a genome-terminal region of duplicated genes involved in host immune system evasion. As expected from its function, this is a region of maintenance of ancestral polymorphism: The lack of clear splitting signal cannot be interpreted as evidence of introgression. The EastMCMV genome sequences reported here can therefore serve as a well-described resource for exploration of murid MCMV diversity.
Collapse
Affiliation(s)
- Dagmar Čížková
- Institute of Vertebrate Biology of the Czech Academy of Sciences, Brno, Czech Republic.
| | - Stuart J E Baird
- Institute of Vertebrate Biology of the Czech Academy of Sciences, Brno, Czech Republic
| | - Jana Těšíková
- Institute of Vertebrate Biology of the Czech Academy of Sciences, Brno, Czech Republic; Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Sebastian Voigt
- Department of Pediatric Oncology/Hematology/Stem Cell Transplantation, Charité-Universitätsmedizin, Berlin, Germany; Department of Infectious Diseases, Robert Koch Institute, Berlin, Germany
| | - Ďureje Ľudovít
- Institute of Vertebrate Biology of the Czech Academy of Sciences, Brno, Czech Republic
| | - Jaroslav Piálek
- Institute of Vertebrate Biology of the Czech Academy of Sciences, Brno, Czech Republic
| | | |
Collapse
|
9
|
Li W, Sheng J, Xu M, Vu GP, Yang Z, Liu Y, Sun X, Trang P, Lu S, Liu F. Inhibition of Murine Cytomegalovirus Infection in Animals by RNase P-Associated External Guide Sequences. MOLECULAR THERAPY. NUCLEIC ACIDS 2017; 9:322-332. [PMID: 29246310 PMCID: PMC5684469 DOI: 10.1016/j.omtn.2017.10.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 10/12/2017] [Accepted: 10/12/2017] [Indexed: 11/21/2022]
Abstract
External guide sequence (EGS) RNAs are associated with ribonuclease P (RNase P), a tRNA processing enzyme, and represent promising agents for gene-targeting applications as they can direct RNase-P-mediated cleavage of a target mRNA. Using murine cytomegalovirus (MCMV) as a model system, we examined the antiviral effects of an EGS variant, which was engineered using in vitro selection procedures. EGSs were used to target the shared mRNA region of MCMV capsid scaffolding protein (mCSP) and assemblin. In vitro, the EGS variant was 60 times more active in directing RNase P cleavage of the target mRNA than the EGS originating from a natural tRNA. In MCMV-infected cells, the variant reduced mCSP expression by 92% and inhibited viral growth by 8,000-fold. In MCMV-infected mice hydrodynamically transfected with EGS-expressing constructs, the EGS variant was more effective in reducing mCSP expression, decreasing viral production, and enhancing animal survival than the EGS originating from a natural tRNA. These results provide direct evidence that engineered EGS variants with higher targeting activity in vitro are also more effective in reducing gene expression in animals. Furthermore, our findings imply the possibility of engineering potent EGS variants for therapy of viral infections.
Collapse
Affiliation(s)
- Wei Li
- Department of Biotechnology, College of Life Science and Technology, Jinan University, Guangzhou, Guangdong 510632, China
| | - Jingxue Sheng
- Program in Comparative Biochemistry, University of California, Berkeley, Berkeley, CA 94720, USA; School of Public Health, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Mengqiong Xu
- Department of Biotechnology, College of Life Science and Technology, Jinan University, Guangzhou, Guangdong 510632, China
| | - Gia-Phong Vu
- School of Public Health, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Zhu Yang
- Jiangsu Affynigen Biotechnolgies, Inc., Taizhou, Jiangsu 225300, China; Guangzhou Qinheli Biotechnolgies, Inc., Guangzhou, Guangdong 510600, China
| | - Yujun Liu
- Department of Biotechnology, College of Life Science and Technology, Jinan University, Guangzhou, Guangdong 510632, China; School of Medicine, St. George's University, Grenada, West Indies; School of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan, Shandong 250355, China
| | - Xu Sun
- Department of Biotechnology, College of Life Science and Technology, Jinan University, Guangzhou, Guangdong 510632, China; Guangzhou Qinheli Biotechnolgies, Inc., Guangzhou, Guangdong 510600, China
| | - Phong Trang
- Program in Comparative Biochemistry, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Sangwei Lu
- Program in Comparative Biochemistry, University of California, Berkeley, Berkeley, CA 94720, USA; School of Public Health, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Fenyong Liu
- Department of Biotechnology, College of Life Science and Technology, Jinan University, Guangzhou, Guangdong 510632, China; Program in Comparative Biochemistry, University of California, Berkeley, Berkeley, CA 94720, USA; School of Public Health, University of California, Berkeley, Berkeley, CA 94720, USA.
| |
Collapse
|
10
|
Dogra P, Miller-Kittrell M, Pitt E, Jackson JW, Masi T, Copeland C, Wu S, Miller WE, Sparer T. A little cooperation helps murine cytomegalovirus (MCMV) go a long way: MCMV co-infection rescues a chemokine salivary gland defect. J Gen Virol 2016; 97:2957-2972. [PMID: 27638684 DOI: 10.1099/jgv.0.000603] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Cytomegaloviruses (CMVs) produce chemokines (vCXCLs) that have both sequence and functional homology to host chemokines. Assessment of vCXCL-1's role in CMV infection is limited to in vitro and in silico analysis due to CMVs species specificity. In this study, we used the murine CMV (MCMV) mouse model to evaluate the function of vCXCL-1 in vivo. Recombinant MCMVs expressing chimpanzee CMV vCXCL-1 (vCXCL-1CCMV) or host chemokine, mCXCL1, underwent primary dissemination to the popliteal lymph node, spleen and lung similar to the parental MCMV. However, neither of the recombinants expressing chemokines was recovered from the salivary gland (SG) at any time post-infection although viral DNA was detected. This implies that the virus does not grow in the SG or the overexpressed chemokine induces an immune response that leads to suppressed growth. Pointing to immune suppression of virus replication, recombinant viruses were isolated from the SG following infection of immune-ablated mice [i.e. SCID (severe combined immunodeficiency), NSG (non-obese diabetic SCID gamma) or cyclophosphamide treated]. Depletion of neutrophils or NK cells does not rescue the recovery of chemokine-expressing recombinants in the SG. Surprisingly we found that co-infection of parental virus and chemokine-expressing virus leads to the recovery of the recombinants in the SG. We suggest that parental virus reduces the levels of chemokine expression leading to a decrease in inflammatory monocytes and subsequent SG growth. Therefore, aberrant expression of the chemokines induces cells of the innate and adaptive immune system that curtail the growth and dissemination of the recombinants in the SG.
Collapse
Affiliation(s)
- Pranay Dogra
- Department of Microbiology, University of Tennessee, 1414 Cumberland Avenue, Knoxville, TN 37996, USA
| | - Mindy Miller-Kittrell
- Department of Microbiology, University of Tennessee, 1414 Cumberland Avenue, Knoxville, TN 37996, USA
| | - Elisabeth Pitt
- Department of Microbiology, University of Tennessee, 1414 Cumberland Avenue, Knoxville, TN 37996, USA
| | - Joseph W Jackson
- Department of Microbiology, University of Tennessee, 1414 Cumberland Avenue, Knoxville, TN 37996, USA
| | - Tom Masi
- Department of Microbiology, University of Tennessee, 1414 Cumberland Avenue, Knoxville, TN 37996, USA
| | - Courtney Copeland
- Department of Microbiology, University of Tennessee, 1414 Cumberland Avenue, Knoxville, TN 37996, USA
| | - Shuen Wu
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati College of Medicine, 231 Albert Sabin Way, Cincinnati, OH 45267-0524, USA
| | - William E Miller
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati College of Medicine, 231 Albert Sabin Way, Cincinnati, OH 45267-0524, USA
| | - Tim Sparer
- Department of Microbiology, University of Tennessee, 1414 Cumberland Avenue, Knoxville, TN 37996, USA
| |
Collapse
|
11
|
Smee DF, Pease A, Burger RA, Huffman JH, Morrey JD, Okleberry KM, Noble RL, Sidwell RW. Ganciclovir Treatment of Murine Cytomegalovirus Infection in Mice Immunosuppressed by Prior Infection with Friend Leukaemia Virus. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/095632029200300602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Since many of the severe cytomegalovirus infections in humans occur in individuals immunosuppressed by the human immunodeficiency virus, we developed an analogous murine model for studying this disease. BALB/c mice infected with the Friend retrovirus complex (FV) were immunosuppressed (i.e., exhibited reduced spleen-cell mitogenic responses and natural killer cell activity) by 21 days after FV inoculation. Challenge with murine cytomegalovirus (MCMV) at that time led to mortality at doses generally non-lethal to normal mice. Superinfection of FV-infected mice with MCMV reduced spleen cell FV infectious centres and splenomegaly, and extended the lives of mice surviving the MCMV infection. Once-daily ganciclovir treatments of 12.5,25, and 50 mg kg−1 given to dually-infected mice for 5 days starting 24 h after MCMV inoculation resulted in 90–100% survival at 14 days (relative to MCMV inoculation) compared to 15% survival in the placebo group. By 70 days, survival in the drug-treated and placebo groups were 0–5%, these deaths being attributed to FV disease. Ganciclovir treatments reduced MCMV titres in spleen, liver, and kidney during treatment (day 4 of the infection), but lung and salivary gland titres rose between days 7 and 13 in surviving animals. Improved concanavalin A-induced mitogenic responses were noted on day 4 in mice treated with 25 and 50 mg kg−1. These results indicate that the FV/MCMV dual infection in mice can be used as a model for evaluating antiviral agents. Because of the complex nature of the interaction between FV and MCMV, the model may be more appropriate for advanced studies of well-defined viral inhibitors than for routine screening of potential new compounds.
Collapse
Affiliation(s)
- D. F. Smee
- Antiviral Programme, Utah State University, Logan, UT 84322-5600, USA
| | - A. Pease
- Antiviral Programme, Utah State University, Logan, UT 84322-5600, USA
| | - R. A. Burger
- Antiviral Programme, Utah State University, Logan, UT 84322-5600, USA
| | - J. H. Huffman
- Antiviral Programme, Utah State University, Logan, UT 84322-5600, USA
| | - J. D. Morrey
- Antiviral Programme, Utah State University, Logan, UT 84322-5600, USA
| | - K. M. Okleberry
- Antiviral Programme, Utah State University, Logan, UT 84322-5600, USA
| | - R. L. Noble
- Muncie Center for Medical Education, Ball State University, Muncie, IN 47306, USA
| | - R. W. Sidwell
- Antiviral Programme, Utah State University, Logan, UT 84322-5600, USA
| |
Collapse
|
12
|
Spiess K, Jakobsen MH, Kledal TN, Rosenkilde MM. The future of antiviral immunotoxins. J Leukoc Biol 2016; 99:911-25. [PMID: 26729815 DOI: 10.1189/jlb.2mr1015-468r] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 12/03/2015] [Indexed: 01/06/2023] Open
Abstract
There is a constant need for new therapeutic interventions in a wide range of infectious diseases. Over the past few years, the immunotoxins have entered the stage as promising antiviral treatments. Immunotoxins have been extensively explored in cancer treatment and have achieved FDA approval in several cases. Indeed, the design of new anticancer immunotoxins is a rapidly developing field. However, at present, several immunotoxins have been developed targeting a variety of different viruses with high specificity and efficacy. Rather than blocking a viral or cellular pathway needed for virus replication and dissemination, immunotoxins exert their effect by killing and eradicating the pool of infected cells. By targeting a virus-encoded target molecule, it is possible to obtain superior selectivity and drastically limit the side effects, which is an immunotoxin-related challenge that has hindered the success of immunotoxins in cancer treatment. Therefore, it seems beneficial to use immunotoxins for the treatment of virus infections. One recent example showed that targeting of virus-encoded 7 transmembrane (7TM) receptors by immunotoxins could be a future strategy for designing ultraspecific antiviral treatment, ensuring efficient internalization and hence efficient eradication of the pool of infected cells, both in vitro and in vivo. In this review, we provide an overview of the mechanisms of action of immunotoxins and highlight the advantages of immunotoxins as future anti-viral therapies.
Collapse
Affiliation(s)
- Katja Spiess
- Laboratory for Molecular Pharmacology, Department of Neuroscience and Pharmacology, Faculty of Health and Medical Science, University of Copenhagen, Denmark; and
| | - Mette Høy Jakobsen
- Laboratory for Molecular Pharmacology, Department of Neuroscience and Pharmacology, Faculty of Health and Medical Science, University of Copenhagen, Denmark; and
| | - Thomas N Kledal
- Section for Virology, Veterinary Institute, The Danish Technical University, Denmark
| | - Mette M Rosenkilde
- Laboratory for Molecular Pharmacology, Department of Neuroscience and Pharmacology, Faculty of Health and Medical Science, University of Copenhagen, Denmark; and
| |
Collapse
|
13
|
Zhang S, Xiang J, Desmarets LMB, Nauwynck HJ. Pattern of circulation of MCMV mimicking natural infection upon oronasal inoculation. Virus Res 2015; 215:114-20. [PMID: 26732487 DOI: 10.1016/j.virusres.2015.12.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 12/17/2015] [Accepted: 12/21/2015] [Indexed: 01/30/2023]
Abstract
Cytomegaloviruses may infect mammals via oronasal route. However, up till now it remains unclear how this exposure leads to a general infection and shedding. To address this issue, BALB/c female mice were oronasally inoculated with either the highly passaged murine cytomegalovirus (MCMV) Smith or the low passaged MCMV HaNa1. Virus titration showed a productive virus replication of both strains in the nasal mucosa from 1 dpi until the end of the experiment (14 dpi), in lungs from 5 until 14 dpi, and in submandibular glands from 7 until 14 dpi. In contrast to MCMV HaNa1, MCMV Smith also established a low level productive infection in abdominal organs (spleen, liver and kidneys) from 5 dpi (spleen), 7 dpi (liver), and 10 dpi (kidneys) until the end of the experiment. Co-culture showed that for both strains, cell-associated virus was detected in a non-infectious form in nasopharynx-associated lymphoid tissues (NALT) from 1 until 14 dpi, in submandibular lymph nodes from 3 until 5 dpi, in deep cervical lymph nodes from 3 until 14 dpi, in mediastinal lymph nodes from 7 until 14 dpi, in spleen from 5 until at least 10 dpi and in the peripheral blood mononuclear cells (PBMC) at 7 and 10 dpi. The present study shows that upon oronasal exposure, MCMV first enters the nasal mucosa and NALT, from where the virus disseminates to the spleen possibly via the draining lymphatic system and blood; a subsequent cell-associated viremia transports MCMV to submandibular glands and for MCMV Smith also to liver and kidneys, where a second productive replication starts.
Collapse
Affiliation(s)
- Shunchuan Zhang
- Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Jun Xiang
- Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Lowiese M B Desmarets
- Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Hans J Nauwynck
- Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| |
Collapse
|
14
|
Xiang J, Zhang S, Nauwynck H. Infections of neonatal and adult mice with murine CMV HaNa1 strain upon oronasal inoculation: New insights in the pathogenesis of natural primary CMV infections. Virus Res 2015; 211:96-102. [PMID: 26474525 DOI: 10.1016/j.virusres.2015.10.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 10/08/2015] [Accepted: 10/08/2015] [Indexed: 12/17/2022]
Abstract
In healthy individuals, naturally acquired infections of human cytomegalovirus (HCMV) are generally asymptomatic. Animal models mimicking the natural primary HCMV infections in infants and adults are scarce. Here, neonatal and adult BALB/c mice were inoculated oronasally with a Belgian isolate HaNa1 of murine cytomegalovirus (MCMV). None of the mice showed clinical symptoms. In neonatal mice, a typical systemic infection occurred. In adult mice, viral replication was restricted to the nasal mucosa and submandibular glands. Infectious virus was not detected in trachea, oral mucosa, pharynx, esophagus, small intestines of both neonatal and adult mice at all time points. Nose was demonstrated to be the entry site. Double immunofluorescence staining showed that in nose infected cells were olfactory neurons and sustentacular cells in olfactory epithelium and were macrophages and dendritic cells in nasopharynx-associated lymphoid tissues (NALT). Neonatal and adult mice developed similar antibody response pattern, though former magnitude was lower. In summary, we have established intranasal (without anesthesia) infections of neonatal and adult mice with murine CMV HaNa1 strain, which mimic the range and extent of virus replication during natural primary HCMV infections in healthy infants and adults. These findings might bring new insights in the pathogenesis of natural primary CMV infections.
Collapse
Affiliation(s)
- Jun Xiang
- Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Shunchuan Zhang
- Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Hans Nauwynck
- Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| |
Collapse
|
15
|
Zhang S, Xiang J, Van Doorsselaere J, Nauwynck HJ. Comparison of the pathogenesis of the highly passaged MCMV Smith strain with that of the low passaged MCMV HaNa1 isolate in BALB/c mice upon oronasal inoculation. Vet Res 2015; 46:94. [PMID: 26340811 PMCID: PMC4560884 DOI: 10.1186/s13567-015-0228-6] [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: 02/21/2015] [Accepted: 07/29/2015] [Indexed: 11/16/2022] Open
Abstract
Murine cytomegalovirus (MCMV) Smith strain is widely used in mouse models to study HCMV infections. Due to high serial passages, MCMV Smith has acquired genetic and biological changes. Therefore, a low passaged strain would be more relevant to develop mouse models. Here, the pathogenesis of an infection with MCMV Smith was compared with that of an infection with a low passaged Belgian MCMV isolate HaNa1 in BALB/c adult mice following oronasal inoculation with either a low (104 TCID50/mouse) or high (106 TCID50/mouse) inoculation dose. Both strains were mainly replicating in nasal mucosa and submandibular glands for one to two months. In nasal mucosa, MCMV was detected earlier and longer (1–49 days post inoculation (dpi)) and reached higher titers with the high inoculation dose compared to the low inoculation dose (14–35 dpi). In submandibular glands, a similar finding was observed (high dose: 7–49 dpi; low dose: 14–42 dpi). In lungs, both strains showed a restricted replication. In spleen, liver and kidneys, only the Smith strain established a productive infection. The infected cells were identified as olfactory neurons and sustentacular cells in olfactory epithelium, macrophages and dendritic cells in NALT, acinar cells in submandibular glands, and macrophages and epithelial cells in lungs for both strains. Antibody analysis demonstrated for both strains that IgG2a was the main detectable antibody subclass. Overall, our results show that significant phenotypic differences exist between the two strains. MCMV HaNa1 has been shown to be interesting for use in mouse models in order to get better insights for HCMV infections in immunocompetent humans.
Collapse
Affiliation(s)
- Shunchuan Zhang
- Laboratory of Virology, Department of Virology, Parasitology, and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Jun Xiang
- Laboratory of Virology, Department of Virology, Parasitology, and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Jan Van Doorsselaere
- Higher Institute for Nursing and Biotechnology, VIVES University College, Roeselare, Belgium.
| | - Hans J Nauwynck
- Laboratory of Virology, Department of Virology, Parasitology, and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| |
Collapse
|
16
|
Marshall B, Mo J, Covar J, Atherton SS, Zhang M. Decrease of murine cytomegalovirus-induced retinitis by intravenous delivery of immediate early protein-3-specific siRNA. Invest Ophthalmol Vis Sci 2014; 55:4151-7. [PMID: 24906861 DOI: 10.1167/iovs.14-14375] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Retinitis induced by both human and murine cytomegaloviruses following immunosuppression is characterized by progressive loss of retinal architecture, due to necrosis of virus-infected cells as well as widespread apoptosis of uninfected bystander cells. Because small inhibitory RNA molecules (siRNA) can reduce murine cytomegalovirus (MCMV) gene expression and thereby inhibit virus replication in vitro, we tested siRNAs directed against MCMV immediate early protein-3 (IE-3) to determine if MCMV-induced retinitis could be alleviated in vivo. METHODS Immunosuppressed Balb/c mice (2.0 mg methylprednisolone acetate every 3 days beginning on day -2) were infected with 5 × 10(3) pfu of the K181 strain of MCMV via the supraciliary route. At day 2 post infection, mice were treated with various doses of IE-3-specific siRNA ranging from 0.1 nmol to 10 nmol, in a volume of 20 μL PBS via tail vein injection. Injected eyes were collected at various times post inoculation and subjected to plaque assay for virus titer, MCMV antigen staining, H&E staining, TUNEL assay, and Western blot for MCMV IE-3 protein. RESULTS Small but significant amounts of fluorescently labeled IE-3-specific siRNA localized to the RPE layer 48 hours after intravenous injection. IE-3-specific siRNA significantly reduced virus titers at all concentrations tested (ranging from 0.1 nmol to 10 nmol), but the most potent effect of siRNA was observed at a dose of 1 nmol. We also observed that IE-3-specific siRNA produced a substantial decrease in MCMV titers and a substantial reduction in bystander cell apoptosis over the time course of virus infection. CONCLUSIONS Systemic administration of IE-3-specific siRNA could alleviate MCMV retinitis by inhibiting virus replication and subsequent death of uninfected retinal cells.
Collapse
Affiliation(s)
- Brendan Marshall
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta, Georgia, United States
| | - Juan Mo
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta, Georgia, United States
| | - Jason Covar
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta, Georgia, United States
| | - Sally S Atherton
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta, Georgia, United States
| | - Ming Zhang
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta, Georgia, United States
| |
Collapse
|
17
|
Abstract
Although human cytomegalovirus (HCMV) primary infection is generally asymptomatic, in immune-compromised patients HCMV increases morbidity and mortality. As a member of the betaherpesvirus family, in vivo studies of HCMV are limited due to its species specificity. CMVs from other species are often used as surrogates to express HCMV genes/proteins or used as models for inferring HCMV protein function in humans. Using innovative experiments, these animal models have answered important questions about CMV's life cycle, dissemination, pathogenesis, immune evasion, and host immune response. This chapter provides CMV biologists with an overview of the insights gained using these animal models. Subsequent chapters will provide details of the specifics of the experimental methods developed for each of the animal models discussed here.
Collapse
Affiliation(s)
- Pranay Dogra
- Department of Microbiology, University of Tennessee, Knoxville, TN, USA
| | | |
Collapse
|
18
|
Stahl FR, Heller K, Halle S, Keyser KA, Busche A, Marquardt A, Wagner K, Boelter J, Bischoff Y, Kremmer E, Arens R, Messerle M, Förster R. Nodular inflammatory foci are sites of T cell priming and control of murine cytomegalovirus infection in the neonatal lung. PLoS Pathog 2013; 9:e1003828. [PMID: 24348257 PMCID: PMC3861546 DOI: 10.1371/journal.ppat.1003828] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 10/28/2013] [Indexed: 02/01/2023] Open
Abstract
Neonates, including mice and humans, are highly susceptible to cytomegalovirus (CMV) infection. However, many aspects of neonatal CMV infections such as viral cell tropism, spatio-temporal distribution of the pathogen as well as genesis of antiviral immunity are unknown. With the use of reporter mutants of the murine cytomegalovirus (MCMV) we identified the lung as a primary target of mucosal infection in neonatal mice. Comparative analysis of neonatal and adult mice revealed a delayed control of virus replication in the neonatal lung mucosa explaining the pronounced systemic infection and disease in neonates. This phenomenon was supplemented by a delayed expansion of CD8+ T cell clones recognizing the viral protein M45 in neonates. We detected viral infection at the single-cell level and observed myeloid cells forming “nodular inflammatory foci” (NIF) in the neonatal lung. Co-localization of infected cells within NIFs was associated with their disruption and clearance of the infection. By 2-photon microscopy, we characterized how neonatal antigen-presenting cells (APC) interacted with T cells and induced mature adaptive immune responses within such NIFs. We thus define NIFs of the neonatal lung as niches for prolonged MCMV replication and T cell priming but also as sites of infection control. Neonates are highly susceptible to a number of infections that usually cause disease only in immunocompromised individuals, most likely because of their incompletely developed immune system. Although this phenomenon has been frequently observed, immune responses of neonates remain largely undefined upon infections with viruses. There is lack of knowledge about the spatio-temporal dynamics of host-virus interaction, especially in comparative infection models of neonates and adults. In this study, with the use of virus reporter mutants, we provide elaborate insight into these aspects in the mouse model of CMV infection. We define hallmarks of virus tropism, early cellular immune responses and general infection dynamics, findings that are fundamental to understand neonatal antiviral immunity. Furthermore, we found that neonatal APCs induce T cell responses in nodular inflammatory foci of the lung, a process which was supposed to be restricted to lymphoid organs. However, the MCMV-specific T cell response was qualitatively different in neonates from that in adults, possibly explaining - in part - the higher susceptibility of newborns. These observations expand our understanding of where adaptive immunity can be initiated, highlights the importance of early local cellular immune responses and sheds more light on neonatal antiviral immunity.
Collapse
Affiliation(s)
- Felix R. Stahl
- Institute of Immunology, Hannover Medical School, Hannover, Germany
- * E-mail: (FRS); (RF)
| | - Katrin Heller
- Institute of Immunology, Hannover Medical School, Hannover, Germany
| | - Stephan Halle
- Institute of Immunology, Hannover Medical School, Hannover, Germany
| | | | - Andreas Busche
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Anja Marquardt
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Karen Wagner
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Jasmin Boelter
- Institute of Immunology, Hannover Medical School, Hannover, Germany
| | - Yvonne Bischoff
- Institute of Immunology, Hannover Medical School, Hannover, Germany
| | - Elisabeth Kremmer
- Helmholtz Zentrum München, Institut für Molekulare Immunologie, München, Germany
| | - Ramon Arens
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Martin Messerle
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Reinhold Förster
- Institute of Immunology, Hannover Medical School, Hannover, Germany
- * E-mail: (FRS); (RF)
| |
Collapse
|
19
|
Liu LL, Li XF, Qin WQ, Liu XL, Li G, Shu SN, Fang F. Is IL-17 an accomplice contributing to salivary gland damage during CMV infection? Future Virol 2013. [DOI: 10.2217/fvl.13.78] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aim: This study aimed to explore the potential role of IL-17 in the pathological damage to the salivary gland during CMV infection. Materials & methods: For all studies, 4-week-old female BALB/c mice were used. Mouse embryo fibroblast cells were isolated from embryos of pregnant mice. The Smith murine CMV (MCMV) strain was propagated and obtained from homogenates of the salivary glands. BALB/c mice were randomly divided into two groups. Mice in one group were infected with Smith MCMV to establish disseminated infection; mice in the other group were controls. Four mice of each group were randomly chosen to be harvested on days 3, 7, 14 and 28. Viral titers in salivary gland tissues were determined using a standard plaque assay; IL-17+ T cells in the spleen were analyzed by flow cytometry; the expressions of IL-17 and IL-17 receptor (IL-17R) mRNA was measured by reverse transcription PCR; and the pathology of the salivary glands in infected mice were assessed by hematoxylin and eosin staining. Results: The viral titers in salivary gland tissues, which were much higher than those of other organs, elevated on day 7 and peaked on day 14, then gradually declined on day 28. The percentages of CD4+IL-17+ T cells were increased in MCMV-infected mice compared with controls, with the main increase of CD4+IL-17+ T cells being Th17 cells (p < 0.05). In salivary gland tissues, the expression of IL-17 and IL-17R mRNA increased significantly and achieved the highest level on day 14, which was significantly higher than that of the controls (p < 0.05). Compared with controls, serious inflammatory cellular infiltrates in the salivary glands were present on day 7 after MCMV infection, and on day 14, many of the cellular infiltrate became larger and coalesced with neighboring foci. We found that IL-17 and IL-17R were enriched in the salivary glands when the tissues were mainly injured. Conclusion: The results illustrated that the inflammatory factors, IL-17 and IL-17R, possibly contributed to the process of viral infection and played a part in inducing pathological damage of the salivary gland.
Collapse
Affiliation(s)
- Ling-ling Liu
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China
| | - Xu-fang Li
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China
| | - Wen-qing Qin
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China
| | - Xing-lou Liu
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China
| | - Ge Li
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China
| | - Sai-nan Shu
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China
| | - Feng Fang
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China
| |
Collapse
|
20
|
VIPhyb, an antagonist of vasoactive intestinal peptide receptor, enhances cellular antiviral immunity in murine cytomegalovirus infected mice. PLoS One 2013; 8:e63381. [PMID: 23723978 PMCID: PMC3664580 DOI: 10.1371/journal.pone.0063381] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 04/03/2013] [Indexed: 12/22/2022] Open
Abstract
Vasoactive intestinal peptide (VIP) is a neuropeptide hormone that suppresses Th1-mediated cellular immunity. We previously reported that VIP-knockout (VIP-KO) mice have enhanced cellular immune responses and increased survival following murine cytomegalovirus (mCMV) infection in C57BL/6 mice. In this study, we tested whether treatment with a VIP receptor antagonistic peptide protects C57BL/6 and BALB/c mice from mCMV-infection. One week of daily subcutaneous injections of VIPhyb was non-toxic and did not alter frequencies of immune cell subsets in non-infected mice. VIPhyb administration to mCMV-infected C57BL/6 and BALB/c mice markedly enhanced survival, viral clearance, and reduced liver and lung pathology compared with saline-treated controls. The numbers of effector/memory CD8+ T-cells and mature NK cells were increased in VIPhyb-treated mice compared with PBS-treated groups. Pharmacological blockade of VIP-receptor binding or genetic blockade of VIP-signaling prevented the up-regulation of PD-L1 and PD-1 expression on DC and activated CD8+ T-cells, respectively, in mCMV-infected mice, and enhanced CD80, CD86, and MHC-II expression on conventional and plasmacytoid DC. VIPhyb-treatment increased type-I IFN synthesis, numbers of IFN-γ- and TNF-α-expressing NK cells and T-cells, and the numbers of mCMV-M45 epitope-peptide-MHC-I tetramer CD8+ T-cells following mCMV infection. VIP-treatment lowered the percentage of Treg cells in spleens compared with PBS-treated WT mice following mCMV infection, while significantly decreasing levels of serum VEGF induced by mCMV-infection. The mice in all treated groups exhibited similar levels of anti-mCMV antibody titers. Short-term administration of a VIP-receptor antagonist represents a novel approach to enhance innate and adaptive cellular immunity in a murine model of CMV infection.
Collapse
|
21
|
Abstract
As intracellular parasites, viruses rely on many host cell functions to ensure their replication. The early induction of programmed cell death (PCD) in infected cells constitutes an effective antiviral host mechanism to restrict viral spread within an organism. As a countermeasure, viruses have evolved numerous strategies to interfere with the induction or execution of PCD. Slowly replicating viruses such as the cytomegaloviruses (CMVs) are particularly dependent on sustained cell viability. To preserve viability, the CMVs encode several viral cell death inhibitors that target different key regulators of the extrinsic and intrinsic apoptosis pathways. The best-characterized CMV-encoded inhibitors are the viral inhibitor of caspase-8-induced apoptosis (vICA), viral mitochondrial inhibitor of apoptosis (vMIA), and viral inhibitor of Bak oligomerization (vIBO). Moreover, a viral inhibitor of RIP-mediated signaling (vIRS) that blocks programmed necrosis has been identified in the genome of murine CMV (MCMV), indicating that this cell death mode is a particularly important part of the antiviral host response. This review provides an overview of the known cell death suppressors encoded by CMVs and their mechanisms of action.
Collapse
|
22
|
Handke W, Krause E, Brune W. Live or let die: manipulation of cellular suicide programs by murine cytomegalovirus. Med Microbiol Immunol 2012; 201:475-86. [PMID: 22965170 DOI: 10.1007/s00430-012-0264-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Accepted: 08/24/2012] [Indexed: 11/30/2022]
Abstract
Cytomegaloviruses (CMVs) are large double-stranded DNA viruses that replicate slowly and cause life-long persisting infections in their hosts. To achieve this, the CMVs had to evolve numerous countermeasures against innate and adaptive immune responses. Induction of programmed cell death is one important host defense mechanism against intracellular pathogens such as viruses. For a multicellular organism, it is advantageous to let infected cells die in order to thwart viral replication and dissemination. For a virus, by contrast, it is better to inhibit cell death and keep infected cells alive until the viral replication cycle has been completed. As a matter of fact, the CMVs encode a number of proteins devoted to interfering with different forms of programmed cell death: apoptosis and necroptosis. In this review, we summarize the known functions of the four best characterized cell death inhibitors of murine cytomegalovirus (MCMV), which are encoded by open reading frames, M36, m38.5, m41.1, and M45. The viral proteins interact with key molecules within different cell death pathways, namely caspase-8, Bax, Bak, and RIP1/RIP3. In addition, we discuss which events during MCMV infection might trigger apoptosis or necrosis and how MCMV's countermeasures compare to those of other herpesviruses. Since both, MCMV and its natural host, are amenable to genetic manipulation, the mouse model for CMV infection provides a particularly suitable system to study mechanisms of cell death induction and inhibition.
Collapse
Affiliation(s)
- Wiebke Handke
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Martinistr. 52, 20251 Hamburg, Germany
| | | | | |
Collapse
|
23
|
Li JM, Southerland L, Hossain MS, Giver CR, Wang Y, Darlak K, Harris W, Waschek J, Waller EK. Absence of vasoactive intestinal peptide expression in hematopoietic cells enhances Th1 polarization and antiviral immunity in mice. THE JOURNAL OF IMMUNOLOGY 2011; 187:1057-65. [PMID: 21677142 DOI: 10.4049/jimmunol.1100686] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Vasoactive intestinal peptide (VIP) induces regulatory dendritic cells (DC) in vitro that inhibit cellular immune responses. We tested the role of physiological levels of VIP on immune responses to murine CMV (mCMV) using VIP-knockout (VIP-KO) mice and radiation chimeras engrafted with syngenic VIP-KO hematopoietic cells. VIP-KO mice had less weight loss and better survival following mCMV infection compared with wild-type (WT) littermates. mCMV-infected VIP-KO mice had lower viral loads, faster clearance of virus, with increased numbers of IFN-γ(+) NK and NKT cells, and enhanced cytolytic activity of NK cells. Adaptive antiviral cellular immunity was increased in mCMV-infected VIP-KO mice compared with WT mice, with more Th1/Tc1-polarized T cells, fewer IL-10(+) T cells, and more mCMV-M45 epitope peptide MHC class I tetramer(+) CD8(+) T cells (tetramer(+) CD8 T cells). mCMV-immune VIP-KO mice had enhanced ability to clear mCMV peptide-pulsed target cells in vivo. Enhanced antiviral immunity was also seen in WT transplant recipients engrafted with VIP-KO hematopoietic cells, indicating that VIP synthesized by neuronal cells did not suppress immune responses. Following mCMV infection there was a marked upregulation of MHC-II and CD80 costimulatory molecule expression on DC from VIP-KO mice compared with DC from WT mice, whereas programmed death-1 and programmed death ligand-1 expression were upregulated in activated CD8(+) T cells and DC, respectively, in WT mice, but not in VIP-KO mice. Because the absence of VIP in immune cells increased innate and adaptive antiviral immunity by altering costimulatory and coinhibitory pathways, selective targeting of VIP signaling represents an attractive therapeutic target to enhance antiviral immunity.
Collapse
Affiliation(s)
- Jian-Ming Li
- Department of Hematology/Oncology, Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Abstract
The use of RNase P ribozyme (M1GS catalytic RNA) for inhibition of murine cytomegalovirus (MCMV) propagation in mice is described in this chapter. General information about RNase P based technology is included and followed by detailed protocols focused on (1) construction and in vitro cleavage assay of the customized M1GS ribozyme, (2) stable expression of the M1GS RNA and evaluation of its activity in inhibition of viral gene expression and growth in cultured cells, and (3) investigation of M1GS-mediated inhibition of viral infection and pathogenesis in animals. Using these methods, we have successfully constructed catalytic M1-1 RNA against the MCMV assembly protein (mAP) and M80 mRNA. Our recent study has demonstrated that an 80% reduction in the expression of mAP and M80 and a 2,000-fold reduction in viral growth were observed in cells expressing the ribozyme. Furthermore, after the functional ribozyme-expressing constructs were delivered into MCMV-infected SCID mice, a significant reduction of viral gene expression and infection was detected, and the survival of the infected animals was significantly improved. Collectively, our data demonstrate the feasibility of the use of RNase P ribozyme for inhibition of viral gene expression in animals and support the utility of RNase P ribozyme for gene-targeting applications in vivo.
Collapse
Affiliation(s)
- Yong Bai
- Program in Comparative Biochemistry, University of California, Berkeley, CA, USA
| | | | | |
Collapse
|
25
|
Cardin RD, Bravo FJ, Sewell AP, Cummins J, Flamand L, Juteau JM, Bernstein DI, Vaillant A. Amphipathic DNA polymers exhibit antiviral activity against systemic murine Cytomegalovirus infection. Virol J 2009; 6:214. [PMID: 19954538 PMCID: PMC2794273 DOI: 10.1186/1743-422x-6-214] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2009] [Accepted: 12/02/2009] [Indexed: 12/25/2022] Open
Abstract
Background Phosphorothioated oligonucleotides (PS-ONs) have a sequence-independent, broad spectrum antiviral activity as amphipathic polymers (APs) and exhibit potent in vitro antiviral activity against a broad spectrum of herpesviruses: HSV-1, HSV-2, HCMV, VZV, EBV, and HHV-6A/B, and in vivo activity in a murine microbiocide model of genital HSV-2 infection. The activity of these agents against animal cytomegalovirus (CMV) infections in vitro and in vivo was therefore investigated. Results In vitro, a 40 mer degenerate AP (REP 9) inhibited both murine CMV (MCMV) and guinea pig CMV (GPCMV) with an IC50 of 0.045 μM and 0.16 μM, respectively, and a 40 mer poly C AP (REP 9C) inhibited MCMV with an IC50 of 0.05 μM. Addition of REP 9 to plaque assays during the first two hours of infection inhibited 78% of plaque formation whereas addition of REP 9 after 10 hours of infection did not significantly reduce the number of plaques, indicating that REP 9 antiviral activity against MCMV occurs at early times after infection. In a murine model of CMV infection, systemic treatment for 5 days significantly reduced virus replication in the spleens and livers of infected mice compared to saline-treated control mice. REP 9 and REP 9C were administered intraperitoneally for 5 consecutive days at 10 mg/kg, starting 2 days prior to MCMV infection. Splenomegaly was observed in infected mice treated with REP 9 but not in control mice or in REP 9 treated, uninfected mice, consistent with mild CpG-like activity. When REP 9C (which lacks CpG motifs) was compared to REP 9, it exhibited comparable antiviral activity as REP 9 but was not associated with splenomegaly. This suggests that the direct antiviral activity of APs is the predominant therapeutic mechanism in vivo. Moreover, REP 9C, which is acid stable, was effective when administered orally in combination with known permeation enhancers. Conclusion These studies indicate that APs exhibit potent, well tolerated antiviral activity against CMV infection in vivo and represent a new class of broad spectrum anti-herpetic agents.
Collapse
Affiliation(s)
- Rhonda D Cardin
- Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA.
| | | | | | | | | | | | | | | |
Collapse
|
26
|
The M33 chemokine receptor homolog of murine cytomegalovirus exhibits a differential tissue-specific role during in vivo replication and latency. J Virol 2009; 83:7590-601. [PMID: 19439478 DOI: 10.1128/jvi.00386-09] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
M33, encoded by murine cytomegalovirus (MCMV), is a member of the UL33 homolog G-protein-coupled receptor (GPCR) family and is conserved across all the betaherpesviruses. Infection of mice with recombinant viruses lacking M33 or containing specific signaling domain mutations in M33 results in significantly diminished MCMV infection of the salivary glands. To determine the role of M33 in viral dissemination and/or infection in other tissues, viral infection with wild-type K181 virus and an M33 mutant virus, DeltaM33B(T2), was characterized using two different routes of inoculation. Following both intraperitoneal (i.p.) and intranasal (i.n.) inoculation, M33 was attenuated for infection of the spleen and pancreas as early as 7 days after infection. Following i.p. inoculation, DeltaM33B(T2) exhibited a severe defect in latency as measured by a diminished capacity to reactivate from spleens and lungs in reactivation assays (P < 0.001). Subsequent PCR analysis revealed markedly reduced DeltaM33B(T2) viral DNA levels in the latently infected spleens, lungs, and bone marrow. Following i.n. inoculation, latent DeltaM33B(T2) viral DNA was significantly reduced in the spleen and, in agreement with results from i.p. inoculation, did not reactivate from the spleen (P < 0.001). Furthermore, in vivo complementation of DeltaM33B(T2) virus replication and/or dissemination to the salivary glands and pancreas was achieved by coinfection with wild-type virus. Overall, our data suggest a critical tissue-specific role for M33 during infection in the salivary glands, spleen, and pancreas but not the lungs. Our data suggest that M33 contributes to the efficient establishment or maintenance of long-term latent MCMV infection.
Collapse
|
27
|
Cekinović D, Golemac M, Pugel EP, Tomac J, Cicin-Sain L, Slavuljica I, Bradford R, Misch S, Winkler TH, Mach M, Britt WJ, Jonjić S. Passive immunization reduces murine cytomegalovirus-induced brain pathology in newborn mice. J Virol 2008; 82:12172-80. [PMID: 18842707 PMCID: PMC2593357 DOI: 10.1128/jvi.01214-08] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Accepted: 09/25/2008] [Indexed: 12/18/2022] Open
Abstract
Human cytomegalovirus (HCMV) is the most frequent cause of congenital viral infections in humans and frequently leads to long-term central nervous system (CNS) abnormalities that include learning disabilities, microcephaly, and hearing loss. The pathogenesis of the CNS infection has not been fully elucidated and may arise as a result of direct damage of CMV-infected neurons or indirectly secondary to inflammatory response to infection. We used a recently established model of mouse CMV (MCMV) infection in newborn mice to analyze the contribution of humoral immunity to virus clearance from the brain. In brains of MCMV-infected newborn mice treated with immune serum, the titer of infectious virus was reduced below detection limit, whereas in the brains of mice receiving control (nonimmune) serum significant amounts of virus were recovered. Moreover, histopathological and immunohistological analyses revealed significantly less CNS inflammation in mice treated with immune serum. Treatment with MCMV-specific monoclonal antibodies also resulted in the reduction of virus titer in the brain. Recipients of control serum or irrelevant antibodies had more viral foci, marked mononuclear cell infiltrates, and prominent glial nodules in their brains than mice treated with immune serum or MCMV-specific antibodies. In conclusion, our data indicate that virus-specific antibodies have a protective role in the development of CNS pathology in MCMV-infected newborn mice, suggesting that antiviral antibodies may be an important component of protective immunological responses during CMV infection of the developing CNS.
Collapse
Affiliation(s)
- Durdica Cekinović
- Department of Histology and Embryology, Faculty of Medicine, University of Rijeka, B Branchetta 20, Rijeka 51000, Croatia
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Effective inhibition in animals of viral pathogenesis by a ribozyme derived from RNase P catalytic RNA. Proc Natl Acad Sci U S A 2008; 105:10919-24. [PMID: 18663226 DOI: 10.1073/pnas.0804922105] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A functional RNase P ribozyme (M1GS RNA) was constructed to target the overlapping mRNA region of two murine cytomegalovirus (MCMV) capsid proteins essential for viral replication: the assembly protein (mAP) and M80. The customized ribozyme efficiently cleaved the target mRNA sequence in vitro. Moreover, 80% reduction in the expression of mAP and M80 and a 2,000-fold reduction in viral growth were observed in cells expressing the ribozyme. In contrast, there was no significant reduction in viral gene expression and growth in cells that either did not express the ribozyme or produced a "disabled" ribozyme carrying mutations that abolished its catalytic activity. When the ribozyme-expressing constructs were delivered into MCMV-infected SCID mice via a modified "hydrodynamic transfection" procedure, expression of ribozymes was observed in the livers and spleens. Compared with the control animals that did not receive any M1GS constructs or received the disabled ribozyme construct, animals receiving the functional ribozyme construct exhibited a significant reduction of viral gene expression and infection. Viral titers in the spleens, livers, lungs, and salivary glands of the functional ribozyme-treated SCID mice at 21 days after infection were 200- to 2,000-fold lower than those in the control animals. Moreover, survival of the infected animals significantly improved upon receiving the functional ribozyme construct. Our study examines the use of M1GS ribozymes for inhibition of gene expression in animals and demonstrates the utility of RNase P ribozymes for gene targeting applications in vivo.
Collapse
|
29
|
Baluchova K, Kirby M, Ahasan MM, Sweet C. Preliminary characterization of murine cytomegaloviruses with insertional and deletional mutations in the M34 open reading frame. J Med Virol 2008; 80:1233-42. [PMID: 18461610 DOI: 10.1002/jmv.21211] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A viable virus could not be recovered from a mutant murine cytomegalovirus (MCMV) BAC in which the M34 ORF had been deleted (BACDeltaM34). In contrast, an M34 mutant virus (RcM34), in which the M34 ORF was interrupted by transposon insertion at nt 44,827 of the Smith MCMV BAC, was attenuated in replication both in tissue culture and in SCID mice. Similarly, mutant virus Rc3'DeltaM34, in which the 3'-end was deleted from nt 44,724 to nt 45,647, produced similar replication kinetics in tissue culture to RcM34 while BAC5'DeltaM34, in which the 5'-end from nt 43,083 up to nt 44,896 was deleted, was non-viable like BACDeltaM34. A transcript analysis of wt and RcM34 virus-infected cells showed that a truncated transcript encoding a putative protein of 624 amino acids was produced by RcM34, of which the amino terminal 582 amino acids would be identical to the predicted wt 854 amino acids product. Recent, re-annotations of the MCMV genome have identified three putative M34 overlapping ORFs (m33.1, m34.1, and m34.2) that may be interrupted in the above mutants. All three were transcribed in RcM34 virus-infected cells confirming that the RcM34 virus phenotype was probably due to interruption of the M34 ORF. These results suggest that M34, like human CMV UL34, is an essential gene.
Collapse
Affiliation(s)
- Katarina Baluchova
- School of Biosciences, University of Birmingham, Birmingham, United Kingdom
| | | | | | | |
Collapse
|
30
|
Abstract
Human CMV is the predominant infectious cause of congenital birth defects and an opportunistic pathogen in immunosuppressed individuals, including AIDS patients. Most individuals are infected early during their life followed by life-long latent infection. During this latent phase, frequent reactivation and antigen production continue to stimulate the immune system. While the immune response is able to control the virus, it is unable to eradicate it. Moreover, super-infection by different CMV strains has been observed despite a strong immune response. Long-term immune stimulation by CMV has also been implicated in immune senescence and chronic conditions such as atherosclerosis. CMVs are highly species-specific and the relatedness of CMV genomes exactly mirrors the relatedness of their hosts. Thus, each CMV species is highly adapted to its respective host species, but is unable to infect other, even closely related hosts. While fascinating from an evolutionary perspective, this host restriction prevents studying HCMV in experimental animals. Exceptions are severely immunocompromised mice, e.g. SCID mice, or SCID/NOD mice, which might allow partial reconstitution of CMV infection in rodents. More practical however, is to study CMVs in their natural host, e.g. murine, rat or guinea pig CMVs. However, while these small animal models have many advantages, such as the availability of inbred animals as well as lower cost, the limited homology of the viral genomes with HCMV limits the functional analysis of homologous gene products. The closest relative to HCMV is chimpanzee CMV (CCMV), but this is not a practical animal model since chimps are a protected species, extremely expensive and of very limited availability. In contrast, rhesus macaques are a more widely used experimental animal species and, while more distant than CCMV, rhesus CMV (RhCMV) contains most of the HCMV gene families thus allowing the study of their role in acute and latent CMV infection. In this review we will discuss the current state of developing RhCMV as a model for HCMV.
Collapse
|
31
|
Broxmeyer HE, Dent A, Cooper S, Hangoc G, Wang ZY, Du W, Gervay-Haque J, Sriram V, Renukaradhya GJ, Brutkiewicz RR. A role for natural killer T cells and CD1d molecules in counteracting suppression of hematopoiesis in mice induced by infection with murine cytomegalovirus. Exp Hematol 2007; 35:87-93. [PMID: 17379092 DOI: 10.1016/j.exphem.2007.01.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
OBJECTIVE Infection of immunocompromised patients with cytomegalovirus (CMV), such as that occurring in patients undergoing hematopoietic stem cell transplantation, is a serious clinical problem. CMV infection has been reported to suppress hematopoiesis. In immunocompetent hosts CMV is controlled initially by the innate immune system, with CD1d molecules and natural killer T (NKT) cells playing a role in the antiviral immune response in several model systems. We hypothesized that CD1d and NKT cells are involved in protection of the hematopoietic modulating effects of CMV, and that adoptive transfer of NKT cells would protect against these infection-induced effects. METHODS To address our hypothesis, we used a murine CMV (MCMV) infection model in CD1d(-/-), Jalpha18(-/-), and wild-type (WT) control mice of two different genetic strains each. RESULTS Infection with MCMV was associated with significant suppression of absolute numbers and cell cycling status of myeloid progenitor cells (CFU-GM, BFU-E, CFU-GEMM) in the marrow and spleen, especially in CD1d(-/-) (lack both CD1d and NKT cells), and Jalpha18(-/-) (express CD1d but lack NKT cells) mice. Adoptive transfer of NKT cells into WT and Jalpha18(-/-) mice shortly before infection with MCMV counteracted myelosuppression. CONCLUSIONS The results implicate NKT cells, and also likely CD1d, in protection of progenitor cells from MCMV-induced suppression and suggest that NKT cells may be of value in an adoptive transfer setting to treat CMV-induced perturbations of hematopoiesis in immunocompromised individuals. However, further studies are required to better understand the full consequences of adoptive transfer in these settings.
Collapse
Affiliation(s)
- Hal E Broxmeyer
- Department of Microbiology and Immunology and the Walther Oncology Center, Indiana University School of Medicine, and the Walther Cancer Institute, Indianapolis, IN 46202, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Adam SG, Caraux A, Fodil-Cornu N, Loredo-Osti JC, Lesjean-Pottier S, Jaubert J, Bubic I, Jonjic S, Guénet JL, Vidal SM, Colucci F. Cmv4, a New Locus Linked to the NK Cell Gene Complex, Controls Innate Resistance to Cytomegalovirus in Wild-Derived Mice. THE JOURNAL OF IMMUNOLOGY 2006; 176:5478-85. [PMID: 16622016 DOI: 10.4049/jimmunol.176.9.5478] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
CMV can cause life-threatening disease in immunodeficient hosts. Experimental infection in mice has revealed that the genetically determined natural resistance to murine CMV (MCMV) may be mediated either by direct recognition between the NK receptor Ly49H and the pathogen-encoded glycoprotein m157 or by epistatic interaction between Ly49P and the host MHC H-2D(k). Using stocks of wild-derived inbred mice as a source of genetic diversity, we found that PWK/Pas (PWK) mice were naturally resistant to MCMV. Depletion of NK cells subverted the resistance. Analysis of backcrosses to susceptible BALB/c mice revealed that the phenotype was controlled by a major dominant locus effect linked to the NK gene complex. Haplotype analysis of 41 polymorphic markers in the Ly49h region suggested that PWK mice may share a common ancestral origin with C57BL/6 mice; in the latter, MCMV resistance is dependent on Ly49H-m157 interactions. Nevertheless, PWK mice retained viral resistance against m157-defective mutant MCMV. These results demonstrate the presence of yet another NK cell-dependent viral resistance mechanism, named Cmv4, which most likely encodes for a new NK activating receptor. Identification of Cmv4 will expand our understanding of the specificity of the innate recognition of infection by NK cells.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- Antigens, Ly/chemistry
- Antigens, Ly/genetics
- Cytomegalovirus/classification
- Cytomegalovirus/physiology
- Cytomegalovirus Infections/immunology
- Cytomegalovirus Infections/metabolism
- Female
- Haplotypes/genetics
- Immunity, Innate/immunology
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Lectins, C-Type/chemistry
- Lectins, C-Type/genetics
- Ligands
- Male
- Mice
- Molecular Sequence Data
- Multigene Family
- NK Cell Lectin-Like Receptor Subfamily A
- Receptors, Immunologic/metabolism
- Receptors, NK Cell Lectin-Like
- Receptors, Natural Killer Cell
- Receptors, Virus/classification
- Receptors, Virus/metabolism
- Sequence Alignment
Collapse
Affiliation(s)
- Sonia Girard Adam
- Department of Human Genetics, McGill Center for Host Resistance, McGill University, Montreal, Quebec, Canada
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Strobl B, Bubic I, Bruns U, Steinborn R, Lajko R, Kolbe T, Karaghiosoff M, Kalinke U, Jonjic S, Müller M. Novel Functions of Tyrosine Kinase 2 in the Antiviral Defense against Murine Cytomegalovirus. THE JOURNAL OF IMMUNOLOGY 2005; 175:4000-8. [PMID: 16148148 DOI: 10.4049/jimmunol.175.6.4000] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We have recently reported that tyrosine kinase 2 (Tyk2)-deficient mice have a selective defect in the in vivo defense against certain viruses. In our current study we show that Tyk2 is essential for the defense against murine CMV (MCMV). In vivo challenges with MCMV revealed impaired clearance of virus from organs and decreased survival of mice in the absence of Tyk2. Our in vitro studies demonstrate that MCMV replicates to dramatically higher titers in Tyk2-deficient macrophages compared with wild-type cells. We show an essential role of type I IFN (IFN-alphabeta) in the control of MCMV replication, with a prominent role of IFN-beta. MCMV infection leads to the activation of STAT1 and STAT2 in an IFN-alphabeta receptor 1-dependent manner. Consistent with the role of Tyk2 in IFN-alphabeta signaling, activation of STAT1 and STAT2 is reduced in Tyk2-deficient cells. However, lack of Tyk2 results in impaired MCMV-mediated gene induction of only a subset of MCMV-induced IFN-alphabeta-responsive genes. Taken together, our data demonstrate a requirement for Tyk2 in the in vitro and in vivo antiviral defense against MCMV infection. In addition to the established role of Tyk2 as an amplifier of Jak/Stat signaling upon IFN-alphabeta stimulation, we provide evidence for a novel role of Tyk2 as a modifier of host responses.
Collapse
Affiliation(s)
- Birgit Strobl
- Institute of Animal Breeding and Genetics, Veterinary University of Vienna, Vienna, Austria.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Scott GM, Ng HL, Morton CJ, Parker MW, Rawlinson WD. Murine cytomegalovirus resistant to antivirals has genetic correlates with human cytomegalovirus. J Gen Virol 2005; 86:2141-2151. [PMID: 16033961 DOI: 10.1099/vir.0.80910-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Human cytomegalovirus (HCMV) resistance to antivirals is a significant clinical problem. Murine cytomegalovirus (MCMV) infection of mice is a well-described animal model for in vivo studies of CMV pathogenesis, although the mechanisms of MCMV antiviral susceptibility need elucidation. Mutants resistant to nucleoside analogues aciclovir, adefovir, cidofovir, ganciclovir, penciclovir and valaciclovir, and the pyrophosphate analogue foscarnet were generated by in vitro passage of MCMV (Smith) in increasing concentrations of antiviral. All MCMV antiviral resistant mutants contained DNA polymerase mutations identical or similar to HCMV DNA polymerase mutations known to confer antiviral resistance. Mapping of the mutations onto an MCMV DNA polymerase three-dimensional model generated using the Thermococcus gorgonarius Tgo polymerase crystal structure showed that the DNA polymerase mutations potentially confer resistance through changes in regions surrounding a catalytic aspartate triad. The ganciclovir-, penciclovir- and valaciclovir-resistant isolates also contained mutations within MCMV M97 identical or similar to recognized GCV-resistant mutations of HCMV UL97 protein kinase, and demonstrated cross-resistance to antivirals of the same class. This strongly suggests that MCMV M97 has a similar role to HCMV UL97 in the phosphorylation of nucleoside analogue antivirals. All MCMV mutants demonstrated replication-impaired phenotypes, with the lowest titre and plaque size observed for isolates containing mutations in both DNA polymerase and M97. These findings indicate DNA polymerase and protein kinase regions of potential importance for antiviral susceptibility and replication. The similarities between MCMV and HCMV mutations that arise under antiviral selective pressure increase the utility of MCMV as a model for in vivo studies of CMV antiviral resistance.
Collapse
Affiliation(s)
- G M Scott
- School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Kensington 2052, Australia
- School of Medical Sciences, Faculty of Medicine, University of New South Wales, Kensington 2052, Australia
- Virology Division, Department of Microbiology, SEALS, Prince of Wales Hospital, Avoca Street, Randwick 2031, Australia
| | - H-L Ng
- Biota Structural Biology Laboratory, St Vincent's Institute, Fitzroy, Victoria 3065, Australia
| | - C J Morton
- Biota Structural Biology Laboratory, St Vincent's Institute, Fitzroy, Victoria 3065, Australia
| | - M W Parker
- Biota Structural Biology Laboratory, St Vincent's Institute, Fitzroy, Victoria 3065, Australia
| | - W D Rawlinson
- School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Kensington 2052, Australia
- School of Medical Sciences, Faculty of Medicine, University of New South Wales, Kensington 2052, Australia
- Virology Division, Department of Microbiology, SEALS, Prince of Wales Hospital, Avoca Street, Randwick 2031, Australia
| |
Collapse
|
35
|
Brocchieri L, Kledal TN, Karlin S, Mocarski ES. Predicting coding potential from genome sequence: application to betaherpesviruses infecting rats and mice. J Virol 2005; 79:7570-96. [PMID: 15919911 PMCID: PMC1143683 DOI: 10.1128/jvi.79.12.7570-7596.2005] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Prediction of protein-coding regions and other features of primary DNA sequence have greatly contributed to experimental biology. Significant challenges remain in genome annotation methods, including the identification of small or overlapping genes and the assessment of mRNA splicing or unconventional translation signals in expression. We have employed a combined analysis of compositional biases and conservation together with frame-specific G+C representation to reevaluate and annotate the genome sequences of mouse and rat cytomegaloviruses. Our analysis predicts that there are at least 34 protein-coding regions in these genomes that were not apparent in earlier annotation efforts. These include 17 single-exon genes, three new exons of previously identified genes, a newly identified four-exon gene for a lectin-like protein (in rat cytomegalovirus), and 10 probable frameshift extensions of previously annotated genes. This expanded set of candidate genes provides an additional basis for investigation in cytomegalovirus biology and pathogenesis.
Collapse
Affiliation(s)
- Luciano Brocchieri
- Department of Mathematics, Stanford University, Stanford, CA 94305-2125, USA.
| | | | | | | |
Collapse
|
36
|
Deyde V, Rizvanov A, Otteson E, Brandt S, Bego M, Pari G, Kozel T, St Jeor S. Identification of a monoclonal antibody from Peromyscus maniculatus (deer mouse) cytomegalovirus (PCMV) which binds to a protein with homology to the human CMV matrix protein HCMV pp71. J Virol Methods 2004; 123:9-15. [PMID: 15582693 DOI: 10.1016/j.jviromet.2004.08.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2004] [Accepted: 08/16/2004] [Indexed: 11/20/2022]
Abstract
In this study we identified and characterized a monoclonal antibody against the matrix protein of a cytomegalovirus isolated from the common deer mouse (Peromyscus maniculatus) (PCMV). The monoclonal antibody was isolated using previously described technology which could be applied to the production of monoclonal antibodies against zoonotic disease. The antibody was found to react with a protein homologous to the human cytomegalovirus (HCMV) matrix protein (pp71), the product of the UL82 open reading frame (ORF). mAbs were generated from heterologous fusion of spleen cells from PCMV-positive mice and Balb/C P3X63-Ag8.653 myeloma cells. Using this approach, four monoclonal antibodies: B8C4, C12E8, G6A2 and P4E5 were generated. Antibody G6A2 reacted strongly with PCMV-infected cells as well as purified virions on ELISA and immunofluorescence. Western blot analysis, using sucrose gradient-purified virions, demonstrated that this mAb reacted specifically to a single protein with an apparent molecular weight of 71 kDa. The protein band was excised from the gel, purified and subjected to trypsin digestion followed by mass spectrometry. The protein sequences obtained were found to have identity to HCMV UL82 gene product. Sequence analysis indicated that it is the putative HCMV pp71 protein homolog of PCMV. G6A2 mAb did not cross-react with either human or murine recombinant pp71 proteins expressed in mammalian cells.
Collapse
Affiliation(s)
- Varough Deyde
- Cell and Molecular Biology Program, University of Nevada-Reno 1664, North Virginia St., Reno, NV 89557, USA
| | | | | | | | | | | | | | | |
Collapse
|
37
|
Abenes G, Chan K, Lee M, Haghjoo E, Zhu J, Zhou T, Zhan X, Liu F. Murine cytomegalovirus with a transposon insertional mutation at open reading frame m155 is deficient in growth and virulence in mice. J Virol 2004; 78:6891-9. [PMID: 15194765 PMCID: PMC421665 DOI: 10.1128/jvi.78.13.6891-6899.2004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
A pool of murine cytomegalovirus (MCMV) mutants was previously generated by using a Tn3-based transposon mutagenesis approach (X. Zhan, M. Lee, J. Xiao, and F. Liu, J. Virol. 74:7411-7421, 2000). In this study, one of the MCMV mutants, Rvm155, which contained the transposon insertion in open reading frame m155, was characterized in vitro for its replication in tissue culture and in vivo for its growth and virulence in immunodeficient SCID mice. Compared to the wild-type strain and a rescued virus that restored the m155 region, the mutant is significantly deficient in growth in many organs of the infected animals. At 21 days postinfection the titers of Rvm155 in the salivary glands, lungs, spleens, livers, and kidneys of the intraperitoneally infected SCID mice were lower than the titers of the wild-type virus and the rescued virus by 50-, 1,000-, 500-, 100-, and 500-fold, respectively. Moreover, the viral mutant was attenuated in killing the SCID mice, as none of the SCID mice that were intraperitoneally infected with Rvm155 died until 38 days postinfection while all the animals infected with the wild-type and rescued viruses died at 27 days postinfection. Our results provide the first direct evidence that a disruption of m155 expression leads to attenuation of viral virulence and growth in animals. Moreover, these results suggest that m155 is a viral determinant for optimal MCMV growth and virulence in vivo.
Collapse
Affiliation(s)
- Gerardo Abenes
- Division of Infectious Diseases, School of Public Health, University of California, Berkeley, 94720, USA
| | | | | | | | | | | | | | | |
Collapse
|
38
|
Tam A, Zhu J, Hai R, Haghjoo E, Tong T, Zhan X, Lu S, Liu F. Murine cytomegalovirus with a transposon insertional mutation at open reading frame M35 is defective in growth in vivo. J Virol 2003; 77:7746-55. [PMID: 12829814 PMCID: PMC161956 DOI: 10.1128/jvi.77.14.7746-7755.2003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We had previously constructed a pool of murine cytomegalovirus (MCMV) mutants that contained a Tn3-based transposon sequence randomly inserted in the viral genome. In the study reported here, one of the mutants, RvM35, which contains the transposon insertion at open reading frame M35, was characterized both in vitro in tissue cultures and in immunocompetent Balb/c and immunodeficient SCID mice. Our results provide the first direct evidence to suggest that M35 is not essential for viral replication in vitro in NIH 3T3 cells. Compared to the wild-type strain and a rescued virus that restored the M35 region, the viral mutant was attenuated in growth in both the intraperitoneally infected Balb/c and SCID mice. At 21 days postinfection, the titers of the mutant in the salivary glands, lungs, spleens, livers, and kidneys of the SCID mice were lower than the titers of the wild-type Smith strain and the rescued virus by 50,000-, 100-, 10-, 100-, and 50-fold, respectively. Moreover, the growth of RvM35 is severely attenuated in the salivary glands. The virulence of the mutant virus also appears to be attenuated, because no death was observed in SCID mice infected with RvM35 until 35 days postinfection, while all the animals infected with the wild-type and rescued viruses died 27 days postinfection. Our results suggest that M35 is important for MCMV virulence in killing SCID mice and is required for optimal viral growth in vivo, including in the salivary glands.
Collapse
Affiliation(s)
- Ada Tam
- Division of Infectious Diseases, School of Public Health, University of California-Berkeley, Berkeley, CA 94720, USA
| | | | | | | | | | | | | | | |
Collapse
|
39
|
Zhu J, Chen J, Hai R, Tong T, Xiao J, Zhan X, Lu S, Liu F. In vitro and in vivo characterization of a murine cytomegalovirus with a mutation at open reading frame m166. J Virol 2003; 77:2882-91. [PMID: 12584312 PMCID: PMC149767 DOI: 10.1128/jvi.77.5.2882-2891.2003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have recently generated a pool of murine cytomegalovirus (MCMV) mutants by using a Tn3-based transposon mutagenesis approach. In this study, one of the mutants, Rvm166, which contained the transposon sequence at open reading frame m166, was characterized both in tissue culture and in immunocompetent BALB/c mice and immunodeficient SCID mice. The viral mutant replicated as well as the wild-type Smith strain in vitro in NIH 3T3 cells, whereas the transposon insertion precluded the expression of >65% of the m166 open reading frame. Compared to the wild-type strain and a rescued virus that restored the m166 region, the viral mutant was significantly attenuated in growth in both BALB/c and SCID mice that were intraperitoneally infected with the viruses. At 21 days postinfection, the titers of the viral mutant in the salivary glands, lungs, spleens, livers, and kidneys of the infected SCID mice were lower than the titers of the Smith strain and the rescued virus by about 30000-, 10000-, 1000-, 300-, and 800-fold, respectively. Moreover, the virulence of the mutant virus appears to be severely attenuated because no death was found in SCID mice infected with the viral mutant up to 90 days postinfection, whereas all of the animals infected with the wild-type and rescued viruses died at 27 days postinfection. Our results suggest that m166 probably encodes a virulence factor and is required for MCMV virulence in killing SCID mice and for optimal viral growth in vivo.
Collapse
Affiliation(s)
- Jiaming Zhu
- Division of Infectious Diseases, School of Public Health, University of California, Berkeley, California 94720, USA
| | | | | | | | | | | | | | | |
Collapse
|
40
|
Lee M, Abenes G, Zhan X, Dunn W, Haghjoo E, Tong T, Tam A, Chan K, Liu F. Genetic analyses of gene function and pathogenesis of murine cytomegalovirus by transposon-mediated mutagenesis. J Clin Virol 2002; 25 Suppl 2:S111-22. [PMID: 12361762 DOI: 10.1016/s1386-6532(02)00096-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Murine cytomegalovirus (MCMV) has a linear genome of 230 kb and encodes more than 170 genes, many of which have not been extensively studied for their functions in pathogenesis in vivo. A Tn3-based transposon was constructed and used to generate MCMV mutants by disrupting viral gene targets. The functions of the mutated genes were investigated by studying the viral mutants in cultured cells and in immunocompetent Balb/c and immunodeficient SCID mice. A pool of MCMV mutants that contained the transposon sequence randomly inserted at the viral genome was generated. Studies of several mutants (e.g. a viral mutant with the transposon inserted at open reading frame m09) in cultured cells and in mice indicate that the presence of the transposon sequence per se in the viral genome does not significantly affect viral growth in vitro and in vivo. Moreover, the genome structures of the viral mutants, including the transposon insertion regions, were stable during replication in cultured cells and in animals. Several viral mutants (e.g. a viral mutant with the transposon at M27) that are attenuated in growth and virulence in animals were identified. These results suggest that the genes mutated in these viral mutants may be important for viral virulence and pathogenesis. The Tn3-based system may be a useful tool for the systematic construction of CMV mutants and for studies of CMV gene functions in viral replication in vitro and in pathogenesis in vivo.
Collapse
Affiliation(s)
- Manfred Lee
- Division of Infectious Diseases, School of Public Health, University of California, Berkeley, CA 94720, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Wu CA, Puddington L, Whiteley HE, Yiamouyiannis CA, Schramm CM, Mohammadu F, Thrall RS. Murine cytomegalovirus infection alters Th1/Th2 cytokine expression, decreases airway eosinophilia, and enhances mucus production in allergic airway disease. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:2798-807. [PMID: 11509625 DOI: 10.4049/jimmunol.167.5.2798] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Concomitant infection of murine CMV (MCMV), an opportunistic respiratory pathogen, altered Th1/Th2 cytokine expression, decreased bronchoalveolar lavage (BAL) fluid eosinophilia, and increased mucus production in a murine model of OVA-induced allergic airway disease. Although no change in the total number of leukocytes infiltrating the lung was observed between challenged and MCMV/challenged mice, the cellular profile differed dramatically. After 10 days of OVA-aerosol challenge, eosinophils comprised 64% of the total leukocyte population in BAL fluid from challenged mice compared with 11% in MCMV/challenged mice. Lymphocytes increased from 11% in challenged mice to 30% in MCMV/challenged mice, and this increase corresponded with an increase in the ratio of CD8(+) to CD4(+)TCRalphabeta lymphocytes. The decline in BAL fluid eosinophilia was associated with a change in local Th1/Th2 cytokine profiles. Enhanced levels of IL-4, IL-5, IL-10, and IL-13 were detected in lung tissue from challenged mice by RNase protection assays. In contrast, MCMV/challenged mice transiently expressed elevated levels of IFN-gamma and IL-10 mRNAs, as well as decreased levels of IL-4, IL-5, and IL-13 mRNAs. Elevated levels of IFN-gamma and reduced levels of IL-5 were also demonstrated in BAL fluid from MCMV/challenged mice. Histological evaluation of lung sections revealed extensive mucus plugging and epithelial cell hypertrophy/hyperplasia only in MCMV/challenged mice. Interestingly, the development of airway hyperresponsiveness was observed in challenged mice, not MCMV/challenged mice. Thus, MCMV infection can modulate allergic airway inflammation, and these findings suggest that enhanced mucus production may occur independently of BAL fluid eosinophilia.
Collapse
Affiliation(s)
- C A Wu
- Department of Medicine, University of Connecticut School of Medicine, Farmington, CT 06030, USA.
| | | | | | | | | | | | | |
Collapse
|
42
|
Noda S, Tanaka K, Sawamura S, Sasaki M, Matsumoto T, Mikami K, Aiba Y, Hasegawa H, Kawabe N, Koga Y. Role of nitric oxide synthase type 2 in acute infection with murine cytomegalovirus. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:3533-41. [PMID: 11207313 DOI: 10.4049/jimmunol.166.5.3533] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Whether or not NO plays a critical role in murine CMV (MCMV) infection has yet to be elucidated. In this study, we examined the role of NO in acute infection with MCMV using NO synthase type 2 (NOS2)-deficient mice. NOS2(-/-) mice were more susceptible to lethal infection with MCMV than NOS2(+/+) mice and generated a much higher peak virus titer in the salivary gland after acute infection. A moderate increase in the MCMV titer was also observed in other organs of NOS2(-/-) mice such as the spleen, lung, and liver. The immune responses to MCMV infection including NK cell cytotoxicity and CTL response in NOS2(-/-) mice were comparable with those of NOS2(+/+) mice. Moreover, the ability to produce IFN-gamma is not impaired in NOS2(-/-) mice after MCMV infection. The peritoneal macrophages from NOS2(-/-) mice, however, exhibited a lower antiviral activity than those from NOS2(+/+) mice, resulting in an enhanced viral replication in macrophages themselves. Treatment of these cells from NOS2(+/+) mice with a selective NOS2 inhibitor decreased the antiviral activity to a level below that obtained with NOS2(-/-) mice. In addition, the absence of NOS2 and NOS2-mediated antiviral activity of macrophages resulted in not only an enhanced MCMV replication and a high mortality but also a consequent risk of the latency. It was thus concluded that the NOS2-mediated antiviral activity of macrophages via NO plays a protective role against MCMV infection at an early and late stage of the infection.
Collapse
MESH Headings
- Acute Disease
- Animals
- Cytotoxicity, Immunologic/genetics
- Herpesviridae Infections/enzymology
- Herpesviridae Infections/genetics
- Herpesviridae Infections/immunology
- Herpesviridae Infections/mortality
- Interferon-gamma/biosynthesis
- Killer Cells, Natural/enzymology
- Killer Cells, Natural/immunology
- Killer Cells, Natural/virology
- Macrophages, Peritoneal/enzymology
- Macrophages, Peritoneal/immunology
- Macrophages, Peritoneal/virology
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Muromegalovirus/growth & development
- Muromegalovirus/immunology
- Nitric Oxide Synthase/deficiency
- Nitric Oxide Synthase/genetics
- Nitric Oxide Synthase/physiology
- Nitric Oxide Synthase Type II
- Survival Rate
- T-Lymphocytes, Cytotoxic/enzymology
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/virology
- Viral Load
- Viral Plaque Assay
- Virus Latency/immunology
- Virus Replication/immunology
Collapse
Affiliation(s)
- S Noda
- Department of Infectious Diseases, Tokai University School of Medicine, Isehara, Kanagawa, Japan.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Abenes G, Lee M, Haghjoo E, Tong T, Zhan X, Liu F. Murine cytomegalovirus open reading frame M27 plays an important role in growth and virulence in mice. J Virol 2001; 75:1697-707. [PMID: 11160668 PMCID: PMC114079 DOI: 10.1128/jvi.75.4.1697-1707.2001] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Using a Tn3-based transposon mutagenesis approach, we have generated a pool of murine cytomegalovirus (MCMV) mutants. In this study, one of the mutants, RvM27, which contained the transposon sequence at open reading frame M27, was characterized both in tissue culture and in immunocompetent BALB/c mice and immunodeficient SCID mice. Our results suggest that the M27 carboxyl-terminal sequence is dispensable for viral replication in vitro. Compared to the wild-type strain and a rescued virus that restored the M27 region, RvM27 was attenuated in growth in both BALB/c and SCID mice that were intraperitoneally infected with the viruses. Specifically, the titers of RvM27 in the salivary glands, lungs, spleens, livers, and kidneys of the infected SCID mice at 21 days postinfection were 50- to 500-fold lower than those of the wild-type virus and the rescued virus. Moreover, the virulence of the mutant virus appeared to be attenuated, because no deaths occurred among SCID mice infected with RvM27 for up to 37 days postinfection, while all the animals infected with the wild-type and rescued viruses died within 27 days postinfection. Our observations provide the first direct evidence to suggest that a disruption of M27 expression results in reduced viral growth and attenuated viral virulence in vivo in infected animals. Moreover, these results suggest that M27 is a viral determinant required for optimal MCMV growth and virulence in vivo and provide insight into the functions of the M27 homologues found in other animal and human CMVs as well as in other betaherpesviruses.
Collapse
Affiliation(s)
- G Abenes
- Program in Infectious Diseases and Immunity, School of Public Health, University of California, Berkeley, California 94720, USA
| | | | | | | | | | | |
Collapse
|
44
|
Lee M, Xiao J, Haghjoo E, Zhan X, Abenes G, Tuong T, Dunn W, Liu F. Murine cytomegalovirus containing a mutation at open reading frame M37 is severely attenuated in growth and virulence in vivo. J Virol 2000; 74:11099-107. [PMID: 11070005 PMCID: PMC113190 DOI: 10.1128/jvi.74.23.11099-11107.2000] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A pool of murine cytomegalovirus (MCMV) mutants was generated by using a Tn3-based transposon mutagenesis procedure. One of the mutants, RvM37, which contained the transposon sequence at open reading frame M37, was characterized both in tissue culture and in immunocompetent BALB/c and immunodeficient SCID mice. Our results provide the first direct evidence to suggest that M37 is not essential for viral replication in vitro in NIH 3T3 cells. Compared to the wild-type strain and a rescued virus that restored the M37 region, the viral mutant was severely attenuated in growth in both BALB/c and SCID mice after intraperitoneal infection. Specifically, titers of the Smith strain and rescued virus in the salivary glands, lungs, spleens, livers, and kidneys of the SCID mice at 21 days postinfection were about 5 x 10(5), 2 x 10(5), 5 x 10(4), 5 x 10(3), and 1 x 10(4) PFU/ml of organ homogenate, respectively; in contrast, titers of RvM37 in these organs were less than 10(2) PFU/ml of organ homogenate. Moreover, the virulence of the mutant virus appeared to be significantly attenuated because none of the SCID mice infected with RvM37 had died by 120 days postinfection, while all animals infected with the wild-type and rescued viruses had died by 26 days postinfection. Our results suggest that M37 probably encodes a virulence factor and is required for MCMV virulence in SCID mice and for optimal viral growth in vivo.
Collapse
Affiliation(s)
- M Lee
- Program in Infectious Diseases and Immunity, School of Public Health, University of California, Berkeley, California 94720, USA
| | | | | | | | | | | | | | | |
Collapse
|
45
|
Xiao J, Tong T, Zhan X, Haghjoo E, Liu F. In vitro and in vivo characterization of a murine cytomegalovirus with a transposon insertional mutation at open reading frame M43. J Virol 2000; 74:9488-97. [PMID: 11000218 PMCID: PMC112378 DOI: 10.1128/jvi.74.20.9488-9497.2000] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have recently generated a pool of murine cytomegalovirus (MCMV) mutants by using a Tn3-based transposon mutagenesis approach. In this study, one of the MCMV mutants, RvM43, which contained the transposon inserted in open reading frame M43, was characterized. Our results provide the first direct evidence to suggest that M43 is not essential for viral replication in vitro in NIH 3T3 cells. Moreover, RvM43 exhibited a titer similar to that of the wild-type virus in the lungs, livers, spleens, and kidneys of both BALB/c and SCID mice and was as virulent as the wild-type virus in killing SCID mice that had been intraperitoneally infected with the viruses. In contrast, titers of the mutant virus in the salivary glands of the infected animals at 21 days postinfection were significantly (100 to 1,000-fold) lower than those of the wild-type virus and a rescued virus that restored the M43 region and its expression. Thus, M43 appears to be not essential for viral growth in vivo in the lungs, livers, spleens, and kidneys of infected animals and is also dispensable for virulence in killing SCID mice. Moreover, our results suggest that M43 is an MCMV determinant for growth in the salivary glands. Studies of viral genes required for replication in the salivary glands are important in understanding the mechanism of viral tropism for the salivary glands and shedding in saliva, which is believed to be one of the major routes of CMV transmission among healthy human populations.
Collapse
Affiliation(s)
- J Xiao
- Program in Infectious Diseases and Immunity, School of Public Health, University of California, Berkeley, California 94720, USA
| | | | | | | | | |
Collapse
|
46
|
Abstract
Five temperature-sensitive mutants (tsm9, tsm13, tsm20, tsm22, tsm30) of murine cytomegalovirus have been shown previously not to produce infectious virus in mice. In the present study, the stage at which these mutants are blocked in their replication in vitro was examined by transcriptional analysis of 4 temporally regulated marker genes (IE-1, E-1, gB and gH) using a semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) coupled with an electron microscopic analysis of infected cells incubated at permissive (33 degrees C) and non-permissive (39 and/or 40 degrees C) temperatures. Replication of tsm13 appeared to be blocked at a late phase of replication after capsid formation while the block appeared to be as early as the immediate-early phase in tsm22- infected cells. In contrast, mutants tsm9, tsm20 and tsm30 were blocked at a maturation step, probably of capsid formation, as gene transcription of all 4 marker genes occurred, albeit at reduced level, at 39 and 40 degrees C but no capsids or virions were produced at 40 degrees C. Replication and transcription of mutants tsm13, tsm20 and tsm30 were also examined in infected mice. Mutant tsm13 showed no gene expression or infectious virus while mutants tsm20 and tsm30 produced no infectious virus from days 3-60 post infection, except unusually for a low titre of tsm30 (2.3 x 10(3) pfu/ml) in salivary glands 21 days post infection. Gene transcription of all 4 marker genes was observed in one or more tissues (salivary glands, spleen, kidneys, liver, thymus, heart, lungs) at one or more time points (3, 7, 10, 14, 21 days post-infection) with both mutants. Mice became infected latently with tsm20 but not tsm30, and mice previously infected with tsm20 or tsm30 were protected against a sub-lethal challenge with virulent parental virus; tsm30 also protected against a lethal challenge. This suggests that these two mutants may be good model vaccines for further studies on the mechanism of protection induced and for identification of the ts genes.
Collapse
Affiliation(s)
- T A Gill
- Microbial Molecular Genetics and Cell Biology research Group, School of Biosciences, The University of Birmingham, Birmingham, B15 2TT
| | | | | |
Collapse
|
47
|
Zhan X, Lee M, Xiao J, Liu F. Construction and characterization of murine cytomegaloviruses that contain transposon insertions at open reading frames m09 and M83. J Virol 2000; 74:7411-21. [PMID: 10906194 PMCID: PMC112261 DOI: 10.1128/jvi.74.16.7411-7421.2000] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A transposon derived from Escherichia coli Tn3 was introduced into the genome of murine cytomegalovirus (MCMV) to generate a pool of viral mutants, including two recombinant viruses that contained the transposon sequence within open reading frames m09 and M83. Our studies provide the first direct evidence to suggest that m09 is not essential for viral replication in mouse NIH 3T3 cells. Studies in cultured cells and in both BALB/c-Byj and CB17 severe combined immunodeficient (SCID) mice indicated that the transposon insertion is stable during viral propagation both in vitro and in vivo. Moreover, the virus that contained the insertion mutation in m09 exhibited a titer similar to that of the wild-type virus in the salivary glands, lungs, livers, spleens, and kidneys of both the BALB/c and SCID mice and was as virulent as the wild-type virus in killing the SCID mice when these animals were intraperitoneally infected with these viruses. These results suggest that m09 is dispensable for viral growth in these organs and that the presence of the transposon sequence in the viral genome does not significantly affect viral replication in vivo. In contrast, the virus that contained the insertion mutation in M83 exhibited a titer of at least 60-fold lower than that of the wild-type virus in the organs of the SCID mice and was attenuated in killing the SCID mice. These results demonstrate the utility of using the Tn3-based system as a mutagenesis approach for studying the function of MCMV genes in both immunocompetent and immunodeficient animals.
Collapse
Affiliation(s)
- X Zhan
- Program in Infectious Diseases and Immunity, School of Public Health, University of California, Berkeley, California 94720, USA
| | | | | | | |
Collapse
|
48
|
Zhan X, Lee M, Abenes G, Von Reis I, Kittinunvorakoon C, Ross-Macdonald P, Snyder M, Liu F. Mutagenesis of murine cytomegalovirus using a Tn3-based transposon. Virology 2000; 266:264-74. [PMID: 10639313 DOI: 10.1006/viro.1999.0089] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A transposon derived from Escherichia coli Tn3 was introduced into the genome of murine cytomegalovirus (MCMV) to generate a pool of viral mutants. We analyzed three of the constructed recombinant viruses that contained the transposon within the M25, M27, and m155 open reading frames. Our studies provide the first direct evidence to suggest that M25 and M27 are not essential for viral replication in mouse NIH 3T3 cells. Studies in cultured cells and Balb/c mice indicated that the transposon insertion is stable during viral propagation both in vitro and in vivo. Moreover the virus that contained the insertion mutation in M25 exhibited a titer similar to that of the wild-type virus in the salivary glands, lungs, livers, spleens, and kidneys of the Balb/c mice that were intraperitoneally infected with these viruses. These results suggest that M25 is dispensable for viral growth in these organs and the presence of the transposon sequence in the viral genome does not significantly affect viral replication in vivo. The Tn3-based system can be used as a mutagenesis approach for studying the function of MCMV genes in both tissue culture and in animals.
Collapse
Affiliation(s)
- X Zhan
- Program in Infectious Diseases and Immunity, School of Public Health, University of California, 140 Warren Hall, Berkeley, California, 94720, USA
| | | | | | | | | | | | | | | |
Collapse
|
49
|
Wagner M, Jonjic S, Koszinowski UH, Messerle M. Systematic excision of vector sequences from the BAC-cloned herpesvirus genome during virus reconstitution. J Virol 1999; 73:7056-60. [PMID: 10400809 PMCID: PMC112796 DOI: 10.1128/jvi.73.8.7056-7060.1999] [Citation(s) in RCA: 269] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recently the mouse cytomegalovirus (MCMV) genome was cloned as an infectious bacterial artificial chromosome (BAC) (M. Messerle, I. Crnkovic, W. Hammerschmidt, H. Ziegler, and U. H. Koszinowski, Proc. Natl. Acad. Sci. USA 94:14759-14763, 1997). The virus obtained from this construct is attenuated in vivo due to deletion of viral sequences and insertion of the BAC vector. We reconstituted the full-length MCMV genome and flanked the BAC vector with identical viral sequences. This new construct represents a versatile basis for construction of MCMV mutants since virus generated from the construct loses the bacterial sequences and acquires wild-type properties.
Collapse
Affiliation(s)
- M Wagner
- Max von Pettenkofer-Institut für Hygiene und Medizinische Mikrobiologie, Ludwig-Maximilians-Universität München, D-81377 Munich, Germany
| | | | | | | |
Collapse
|
50
|
Bosio E, Beilharz MW, Watson MW, Lawson CM. Efficacy of low-dose oral use of type I interferon in cytomegalovirus infections in vivo. J Interferon Cytokine Res 1999; 19:869-76. [PMID: 10476931 DOI: 10.1089/107999099313389] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Oral administration of type I interferons (IFNs; murine IFN-alpha and IFN-beta) reduces early replication of murine cytomegalovirus (MCMV) in both the spleen and liver of MCMV-infected BALB/c mice. Examination of a range of doses of IFN (1 to 1000 IU) showed that 10 IU administered daily for 1 week prior to virus infection was optimal for inhibition of MCMV replication. Furthermore, low-dose orally administered IFN (10 IU/day) was effective in mice challenged with lethal and sublethal virus inocula. The antiviral efficacy of low-dose orally administered IFN was not restricted by either the route of virus inoculation or the mouse genotype. Analysis by immunohistochemistry of IFN-alpha receptor-bearing cells of the gastrointestinal tract revealed predominant staining of perivascular smooth muscle and the lamina propria of the anterior tongue, small intestine and rectum. These tissues, dense in IFN-alpha receptor-bearing cells, are likely to be the sites of interaction of the orally administered IFNs with the mucosal immune system. In conclusion, we propose that low-dose oral use of type I IFN therapy may have broad applications in the treatment of CMV infections.
Collapse
Affiliation(s)
- E Bosio
- Department of Microbiology, University of Western Australia, Nedlands, Perth
| | | | | | | |
Collapse
|