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Bender M, Abicht JM, Reichart B, Neumann E, Radan J, Mokelke M, Buttgereit I, Leuschen M, Wall F, Michel S, Ellgass R, Steen S, Paskevicius A, Lange A, Kessler B, Kemter E, Klymiuk N, Denner J, Godehardt AW, Tönjes RR, Burgmann JM, Figueiredo C, Milusev A, Zollet V, Salimi-Afjani N, Despont A, Rieben R, Ledderose S, Walz C, Hagl C, Ayares D, Wolf E, Schmoeckel M, Brenner P, Binder U, Gebauer M, Skerra A, Längin M. Combination of Anti-CD40 and Anti-CD40L Antibodies as Co-Stimulation Blockade in Preclinical Cardiac Xenotransplantation. Biomedicines 2024; 12:1927. [PMID: 39200391 PMCID: PMC11351779 DOI: 10.3390/biomedicines12081927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2024] [Revised: 08/08/2024] [Accepted: 08/09/2024] [Indexed: 09/02/2024] Open
Abstract
The blockade of the CD40/CD40L immune checkpoint is considered essential for cardiac xenotransplantation. However, it is still unclear which single antibody directed against CD40 or CD40L (CD154), or which combination of antibodies, is better at preventing organ rejection. For example, the high doses of antibody administered in previous experiments might not be feasible for the treatment of humans, while thrombotic side effects were described for first-generation anti-CD40L antibodies. To address these issues, we conducted six orthotopic pig-to-baboon cardiac xenotransplantation experiments, combining a chimeric anti-CD40 antibody with an investigational long-acting PASylated anti-CD40L Fab fragment. The combination therapy effectively resulted in animal survival with a rate comparable to a previous study that utilized anti-CD40 monotherapy. Importantly, no incidence of thromboembolic events associated with the administration of the anti-CD40L PAS-Fab was observed. Two experiments failed early because of technical reasons, two were terminated deliberately after 90 days with the baboons in excellent condition and two were extended to 120 and 170 days, respectively. Unexpectedly, and despite the absence of any clinical signs, histopathology revealed fungal infections in all four recipients. This study provides, for the first time, insights into a combination therapy with anti-CD40/anti-CD40L antibodies to block this immune checkpoint.
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Affiliation(s)
- Martin Bender
- Department of Anaesthesiology, University Hospital, LMU Munich, 81377 Munich, Germany
| | - Jan-Michael Abicht
- Department of Anaesthesiology, University Hospital, LMU Munich, 81377 Munich, Germany
| | - Bruno Reichart
- Transregional Collaborative Research Center 127, Walter Brendel Centre of Experimental Medicine, LMU Munich, 81377 Munich, Germany
| | - Elisabeth Neumann
- Transregional Collaborative Research Center 127, Walter Brendel Centre of Experimental Medicine, LMU Munich, 81377 Munich, Germany
| | - Julia Radan
- Transregional Collaborative Research Center 127, Walter Brendel Centre of Experimental Medicine, LMU Munich, 81377 Munich, Germany
| | - Maren Mokelke
- Transregional Collaborative Research Center 127, Walter Brendel Centre of Experimental Medicine, LMU Munich, 81377 Munich, Germany
| | - Ines Buttgereit
- Department of Anaesthesiology, University Hospital, LMU Munich, 81377 Munich, Germany
| | - Maria Leuschen
- Transregional Collaborative Research Center 127, Walter Brendel Centre of Experimental Medicine, LMU Munich, 81377 Munich, Germany
| | - Felicia Wall
- Transregional Collaborative Research Center 127, Walter Brendel Centre of Experimental Medicine, LMU Munich, 81377 Munich, Germany
| | - Sebastian Michel
- Department of Cardiac Surgery, University Hospital, LMU Munich, 81377 Munich, Germany
- Munich Heart Alliance, German Center for Cardiovascular Research (DZHK), 81377 Munich, Germany
| | - Reinhard Ellgass
- Department of Cardiac Surgery, University Hospital, LMU Munich, 81377 Munich, Germany
| | - Stig Steen
- Department of Cardiothoracic Surgery, Lund University and Skåne University Hospital, 22242 Lund, Sweden
| | - Audrius Paskevicius
- Department of Cardiothoracic Surgery, Lund University and Skåne University Hospital, 22242 Lund, Sweden
| | - Andreas Lange
- Institute of Molecular Animal Breeding and Biotechnology, Gene Center, and Department of Veterinary Sciences, LMU Munich, 81377 Munich, Germany
| | - Barbara Kessler
- Institute of Molecular Animal Breeding and Biotechnology, Gene Center, and Department of Veterinary Sciences, LMU Munich, 81377 Munich, Germany
| | - Elisabeth Kemter
- Institute of Molecular Animal Breeding and Biotechnology, Gene Center, and Department of Veterinary Sciences, LMU Munich, 81377 Munich, Germany
| | - Nikolai Klymiuk
- Institute of Molecular Animal Breeding and Biotechnology, Gene Center, and Department of Veterinary Sciences, LMU Munich, 81377 Munich, Germany
| | - Joachim Denner
- Institute of Virology, Free University Berlin, 14163 Berlin, Germany
| | - Antonia W. Godehardt
- Division of Haematology, Cell and Gene Therapy, Paul-Ehrlich-Institut, 63225 Langen, Germany
| | - Ralf R. Tönjes
- Division of Haematology, Cell and Gene Therapy, Paul-Ehrlich-Institut, 63225 Langen, Germany
| | - Jonathan M. Burgmann
- Institute of Transfusion Medicine and Transplant Engineering, Hannover Medical School, 30625 Hannover, Germany
| | - Constança Figueiredo
- Institute of Transfusion Medicine and Transplant Engineering, Hannover Medical School, 30625 Hannover, Germany
| | - Anastasia Milusev
- Department for BioMedical Research (DBMR), University of Bern, 3008 Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, 3008 Bern, Switzerland
| | - Valentina Zollet
- Department for BioMedical Research (DBMR), University of Bern, 3008 Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, 3008 Bern, Switzerland
| | - Neda Salimi-Afjani
- Department for BioMedical Research (DBMR), University of Bern, 3008 Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, 3008 Bern, Switzerland
| | - Alain Despont
- Department for BioMedical Research (DBMR), University of Bern, 3008 Bern, Switzerland
| | - Robert Rieben
- Department for BioMedical Research (DBMR), University of Bern, 3008 Bern, Switzerland
| | - Stephan Ledderose
- Institute of Pathology, Faculty of Medicine, LMU Munich, 81377 Munich, Germany
| | - Christoph Walz
- Institute of Pathology, Faculty of Medicine, LMU Munich, 81377 Munich, Germany
| | - Christian Hagl
- Department of Cardiac Surgery, University Hospital, LMU Munich, 81377 Munich, Germany
- Munich Heart Alliance, German Center for Cardiovascular Research (DZHK), 81377 Munich, Germany
| | | | - Eckhard Wolf
- Institute of Molecular Animal Breeding and Biotechnology, Gene Center, and Department of Veterinary Sciences, LMU Munich, 81377 Munich, Germany
- Center for Innovative Medical Models (CiMM), LMU Munich, 81377 Munich, Germany
- Interfaculty Center for Endocrine and Cardiovascular Disease Network Modelling and Clinical Transfer (ICONLMU), LMU Munich, 81377 Munich, Germany
| | - Michael Schmoeckel
- Department of Cardiac Surgery, University Hospital, LMU Munich, 81377 Munich, Germany
| | - Paolo Brenner
- Department of Cardiac Surgery, University Hospital, LMU Munich, 81377 Munich, Germany
| | - Uli Binder
- XL-protein GmbH, 85354 Freising, Germany
| | | | - Arne Skerra
- Chair of Biological Chemistry, School of Life Sciences, Technical University of Munich, 85354 Freising, Germany
| | - Matthias Längin
- Department of Anaesthesiology, University Hospital, LMU Munich, 81377 Munich, Germany
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Jhelum H, Kaufer B, Denner J. Application of Methods Detecting Xenotransplantation-Relevant Viruses for Screening German Slaughterhouse Pigs. Viruses 2024; 16:1119. [PMID: 39066281 PMCID: PMC11281539 DOI: 10.3390/v16071119] [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: 06/21/2024] [Revised: 07/09/2024] [Accepted: 07/10/2024] [Indexed: 07/28/2024] Open
Abstract
Detection methods have been developed to prevent transmission of zoonotic or xenozoonotic porcine viruses after transplantation of pig organs or cells to the recipient (xenotransplantation). Eleven xenotransplantation-relevant viruses, including porcine cytomegalovirus, porcine roseolovirus (PCMV/PRV), porcine lymphotropic herpesviruses -1, -2, -3 (PLHV-1, 2, 3), porcine parvovirus (PPV), porcine circovirus 2, 3, 4 (PCV2, 3, 4), hepatitis E virus genotype 3 (HEV3), porcine endogenous retrovirus-C (PERV-C), and recombinant PERV-A/C have been selected. In the past, several pig breeds, minipigs, and genetically modified pigs generated for xenotransplantation had been analyzed using these methods. Here, spleen, liver, and blood samples from 10 German slaughterhouse pigs were screened using both PCR-based and immunological assays. Five viruses: PCMV/PRV, PLHV-1, PLHV-3, and PERV-C, were found in all animals, and PCV3 in one animal. Some animals were latently infected with PCMV/PRV, as only virus-specific antibodies were detected. Others were also PCR positive in the spleen and/or liver, indicative of an ongoing infection. These results provide important information on the viruses that infect German slaughterhouse pigs, and together with the results of previous studies, they reveal that the methods and test strategies efficiently work under field conditions.
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Affiliation(s)
| | | | - Joachim Denner
- Institute of Virology, Free University Berlin, 14163 Berlin, Germany; (H.J.); (B.K.)
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3
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Jezdimirović N, Savić B, Milovanović B, Glišić D, Ninković M, Kureljušić J, Maletić J, Aleksić Radojković J, Kasagić D, Milićević V. Molecular Detection of Porcine Cytomegalovirus, Porcine Parvovirus, Aujeszky Disease Virus and Porcine Reproductive and Respiratory Syndrome Virus in Wild Boars Hunted in Serbia during 2023. Vet Sci 2024; 11:249. [PMID: 38921996 PMCID: PMC11209600 DOI: 10.3390/vetsci11060249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 05/17/2024] [Accepted: 05/21/2024] [Indexed: 06/27/2024] Open
Abstract
Porcine cytomegalovirus (PCMV) infection is widespread worldwide and has a high prevalence in swine herds, especially in countries with intensive swine production. PCMV is zoonotic and can impact xenotransplants. It is the third swine virus known to be zoonotic, following swine influenza virus (influenza A) and hepatitis E virus genotype 3 (HEVgt3 or HEV-3). Wild boars, serving as reservoirs for various pathogens, including PCMV, pose a risk to both the pig industry and public health. This study aimed to investigate PCMV infection in Serbian wild boars using real-time PCR and assess other viral infections. We also tested samples for the presence of other viral infections: Aujeszky disease virus (ADV), Porcine parvovirus (PPV) and Porcine reproductive respiratory syndrome (PRRSV). Samples from 50 wild boars across 3 districts were tested. Results showed 8% positivity for PCMV DNA, with females showing higher infection rates. Porcine parvovirus (PPV) was detected in 56% of samples, while Porcine reproductive respiratory syndrome virus (PRRSV) was absent. ADV was found in 18% of samples, primarily in younger animals. This research contributes to understanding PCMV prevalence in Serbian wild boars and emphasizes the importance of monitoring viral infections in wild populations, considering the potential zoonotic and economic implications.
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Affiliation(s)
- Nemanja Jezdimirović
- Scientific Institute of Veterinary Medicine of Serbia, Janisa Janulisa 14, 11000 Belgrade, Serbia
| | - Božidar Savić
- Scientific Institute of Veterinary Medicine of Serbia, Janisa Janulisa 14, 11000 Belgrade, Serbia
| | - Bojan Milovanović
- Scientific Institute of Veterinary Medicine of Serbia, Janisa Janulisa 14, 11000 Belgrade, Serbia
| | - Dimitrije Glišić
- Scientific Institute of Veterinary Medicine of Serbia, Janisa Janulisa 14, 11000 Belgrade, Serbia
| | - Milan Ninković
- Scientific Institute of Veterinary Medicine of Serbia, Janisa Janulisa 14, 11000 Belgrade, Serbia
| | - Jasna Kureljušić
- Scientific Institute of Veterinary Medicine of Serbia, Janisa Janulisa 14, 11000 Belgrade, Serbia
| | - Jelena Maletić
- Scientific Institute of Veterinary Medicine of Serbia, Janisa Janulisa 14, 11000 Belgrade, Serbia
| | - Jelena Aleksić Radojković
- Forensic Veterinary Medicine, Faculty of Veterinary Medicine, University of Belgrade, Bulevar Oslobođenja 18, 11000 Belgrade, Serbia
| | - Dragan Kasagić
- PI Veterinary Institute of the Republic of Srpska “Dr. Vaso Butozan” Banja Luka, Branka Radičevića 18, 78000 Banja Luka, Republic of Srpska, Bosnia and Herzegovina
| | - Vesna Milićević
- Scientific Institute of Veterinary Medicine of Serbia, Janisa Janulisa 14, 11000 Belgrade, Serbia
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Zhou Y, Zhou S, Wang Q, Zhang B. Mitigating Cross-Species Viral Infections in Xenotransplantation: Progress, Strategies, and Clinical Outlook. Cell Transplant 2024; 33:9636897241226849. [PMID: 38258759 PMCID: PMC10807386 DOI: 10.1177/09636897241226849] [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: 09/24/2023] [Revised: 01/02/2024] [Accepted: 01/03/2024] [Indexed: 01/24/2024] Open
Abstract
Xenotransplantation holds great promise as a solution to address the critical shortage of organs, but it raises concerns regarding the potential transmission of porcine viruses to recipients, leading to infections and even zoonotic diseases. Data used in this review were mainly from literature of Pubmed database. Keywords included xenotransplantation, infection, virus, and epidemiology. The original articles and critical reviews selected were relevant to this review's theme. We review the major viral infections of concern in xenotransplantation, their risk of transmission, diagnosis, treatment, and ways to prevent infection. Then, we pivot to a comprehensive overview of the current status of xenotransplantation. In addition, we offer our own insights and recommendations for propelling xenotransplantation forward, transitioning from preclinical experiments to the critical phase of clinical trials. Viral infections pose considerable safety concerns within xenotransplantation, particularly with the possibility of emerging or currently unidentified viruses. Clinical trials serve as a crucial platform to progress the safety standards of xenotransplantation. However, further studies and dedicated efforts are required to effectively translate findings into practical applications that can improve safety measures in this field.
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Affiliation(s)
- Yenong Zhou
- Department of Cardiovascular Surgery, Xijing Hospital, Air Force Medical University, Xi’an, China
| | - Shuyu Zhou
- Inner Mongolia Autonomous Region Hospital of Traditional Chinese Medicine, Hohhot, China
| | - Qian Wang
- Nutriology Department, Qingdao Special Servicemen Recuperation Center of PLA Navy, Qingdao, China
| | - Bing Zhang
- Department of Cardiovascular Surgery, Xijing Hospital, Air Force Medical University, Xi’an, China
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5
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Halecker S, Hansen S, Krabben L, Ebner F, Kaufer B, Denner J. How, where and when to screen for porcine cytomegalovirus (PCMV) in donor pigs for xenotransplantation. Sci Rep 2022; 12:21545. [PMID: 36513687 PMCID: PMC9747970 DOI: 10.1038/s41598-022-25624-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 12/01/2022] [Indexed: 12/14/2022] Open
Abstract
Porcine cytomegalovirus (PCMV), that is actually a porcine roseolovirus (PRV), is a common herpesvirus in domestic pigs and wild boars. In xenotransplantation, PCMV/PRV has been shown to significantly reduce the survival time of pig kidneys and hearts in preclinical trials with different non-human primates. Furthermore, PCMV/PRV has been transmitted in the first pig to human heart xenotransplantation and contributed to the death of the patient. Although transmitted to the recipient, there is no evidence that PCMV/PRV can infect primate cells including human cells. PCMV/PRV is closely related to the human herpesviruses 6 and 7, and only distantly related to the human CMV (HCMV). Antiviral drugs used for the treatment of HCMV are less effective against PCMV/PRV. However, there are well described strategies to eliminate the virus from pig facilities. In order to detect the virus and to eliminate it, highly sensitive detection methods and the knowledge of how, where and when to screen the donor pigs is required. Here, a comparative testing of organs from pigs of different ages using polymerase chain reaction (PCR)-based and immunological methods was performed. Testing young piglets, PCMV/PRV was detected effectively by PCR in blood, bronchoalveolar lavage fluid, tonsils and heart. In adult animals, detection by PCR was not successful in most cases, because the virus load was below the detection limit or the virus was in its latent stage. Therefore, detection of antibodies against selected recombinant proteins corresponding to epitopes detected by nearly all infected animals in a Western blot assay is advantageous. By contrast, immunological testing is not beneficial in young animals as piglets might have PCMV/PRV-specific antibodies obtained from their infected mother via the colostrum. Using a thoughtful combination of PCR-based and immunological methods, detection of PCMV/PRV in donor pigs for xenotransplantation is feasible and a controlled elimination of the virus by early weaning or other methods is possible.
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Affiliation(s)
- S Halecker
- Institute of Virology, Free University, Berlin, Germany
| | - S Hansen
- Institute of Virology, Free University, Berlin, Germany
| | - L Krabben
- Institute of Virology, Free University, Berlin, Germany
| | - F Ebner
- Institute of Immunology, Free University, Berlin, Germany
| | - B Kaufer
- Institute of Virology, Free University, Berlin, Germany
| | - J Denner
- Institute of Virology, Free University, Berlin, Germany.
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6
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Denner J, Bigley TM, Phan TL, Zimmermann C, Zhou X, Kaufer BB. Comparative Analysis of Roseoloviruses in Humans, Pigs, Mice, and Other Species. Viruses 2019; 11:E1108. [PMID: 31801268 PMCID: PMC6949924 DOI: 10.3390/v11121108] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 11/13/2019] [Accepted: 11/27/2019] [Indexed: 12/11/2022] Open
Abstract
Viruses of the genus Roseolovirus belong to the subfamily Betaherpesvirinae, family Herpesviridae. Roseoloviruses have been studied in humans, mice and pigs, but they are likely also present in other species. This is the first comparative analysis of roseoloviruses in humans and animals. The human roseoloviruses human herpesvirus 6A (HHV-6A), 6B (HHV-6B), and 7 (HHV-7) are relatively well characterized. In contrast, little is known about the murine roseolovirus (MRV), also known as murine thymic virus (MTV) or murine thymic lymphotrophic virus (MTLV), and the porcine roseolovirus (PRV), initially incorrectly named porcine cytomegalovirus (PCMV). Human roseoloviruses have gained attention because they can cause severe diseases including encephalitis in immunocompromised transplant and AIDS patients and febrile seizures in infants. They have been linked to a number of neurological diseases in the immunocompetent including multiple sclerosis (MS) and Alzheimer's. However, to prove the causality in the latter disease associations is challenging due to the high prevalence of these viruses in the human population. PCMV/PRV has attracted attention because it may be transmitted and pose a risk in xenotransplantation, e.g., the transplantation of pig organs into humans. Most importantly, all roseoloviruses are immunosuppressive, the humoral and cellular immune responses against these viruses are not well studied and vaccines as well as effective antivirals are not available.
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Affiliation(s)
- Joachim Denner
- Robert Koch Institute, Robert Koch Fellow, 13352 Berlin, Germany
| | - Tarin M. Bigley
- Division of Rheumatology, Department. of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA;
| | - Tuan L. Phan
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA 70118, USA;
- HHV-6 Foundation, Santa Barbara, CA 93108, USA
| | - Cosima Zimmermann
- Institute of Virology, Freie Universität Berlin, 14163 Berlin, Germany;
| | - Xiaofeng Zhou
- Division of Pulmonary and Critical Care Medicine, Department. of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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Goecke NB, Hjulsager CK, Krog JS, Skovgaard K, Larsen LE. Development of a high-throughput real-time PCR system for detection of enzootic pathogens in pigs. J Vet Diagn Invest 2019; 32:51-64. [PMID: 31752620 DOI: 10.1177/1040638719890863] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Respiratory and intestinal diseases in pigs can have significant negative influence on productivity and animal welfare. A wide range of real-time PCR (rtPCR) assays are used in our laboratory (National Veterinary Institute, Technical University of Denmark) for pathogen detection, and PCR analyses are performed on traditional rtPCR platforms in which a limited number of samples can be analyzed per day given limitations in equipment and personnel. To mitigate these restrictions, rtPCR assays have been optimized for the high-throughput rtPCR BioMark platform (Fluidigm). Using this platform, we developed a high-throughput detection system that can be used for simultaneous examination of 48 samples with detection specificity for 18 selected respiratory and enteric viral and bacterial pathogens of high importance to Danish pig production. The rtPCR assays were validated and optimized to run under the same reaction conditions using a BioMark 48.48 dynamic array (DA) integrated fluidic circuit chip, and the sensitivity and specificity were assessed by testing known positive samples. Performance of the 48.48DA was similar to traditional rtPCR analysis, and the specificity of the 48.48DA was high. Application of the high-throughput platform has resulted in a significant reduction in cost and working hours and has provided production herds with a new innovative service with the potential to facilitate the optimal choice of disease control strategies such as vaccination and treatment.
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Affiliation(s)
- Nicole B Goecke
- Division for Diagnostics & Scientific Advice, National Veterinary Institute, Technical University of Denmark, Lyngby, Denmark (Goecke, Hjulsager, Krog, Skovgaard, Larsen)
| | - Charlotte K Hjulsager
- Division for Diagnostics & Scientific Advice, National Veterinary Institute, Technical University of Denmark, Lyngby, Denmark (Goecke, Hjulsager, Krog, Skovgaard, Larsen)
| | - Jesper S Krog
- Division for Diagnostics & Scientific Advice, National Veterinary Institute, Technical University of Denmark, Lyngby, Denmark (Goecke, Hjulsager, Krog, Skovgaard, Larsen)
| | - Kerstin Skovgaard
- Division for Diagnostics & Scientific Advice, National Veterinary Institute, Technical University of Denmark, Lyngby, Denmark (Goecke, Hjulsager, Krog, Skovgaard, Larsen)
| | - Lars E Larsen
- Division for Diagnostics & Scientific Advice, National Veterinary Institute, Technical University of Denmark, Lyngby, Denmark (Goecke, Hjulsager, Krog, Skovgaard, Larsen)
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Egerer S, Fiebig U, Kessler B, Zakhartchenko V, Kurome M, Reichart B, Kupatt C, Klymiuk N, Wolf E, Denner J, Bähr A. Early weaning completely eliminates porcine cytomegalovirus from a newly established pig donor facility for xenotransplantation. Xenotransplantation 2019; 25:e12449. [PMID: 30264883 DOI: 10.1111/xen.12449] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 06/27/2018] [Accepted: 07/10/2018] [Indexed: 01/02/2023]
Abstract
For clinical xenotransplantation, transplants must be free of porcine cytomegalovirus (PCMV). Piglets become infected primarily in the perinatal period by the mother sow. While individual donor animals can be protected from infection by isolation husbandry, success is not guaranteed and this strategy poses the risk of undetected infections and raises animal welfare questions. Here, we present the establishment of a completely PCMV-negative pig herd for breeding donor animals for xenotransplantation. Eleven pregnant DanAvl Basic hybrid sows were purchased from a designated pathogen-free (DPF), PCMV-positive colony and transferred to a new pig facility at the Centre for Innovative Medical Models (CiMM) 4 weeks prior to farrowing. At the age of 24 hours, piglets were early-weaned and transferred to a commercially available Rescue Deck system dedicated to motherless rearing of piglets. Sows were removed from the facility. The PCMV status of F1-generation animals was determined at regular intervals over a period of 14 months by a sensitive real-time PCR-based detection method testing blood, nasal swabs and cultured peripheral blood mononuclear cells (PBMCs). F1 sows were used as recipients of genetically modified embryos to generate a xenotransplant donor herd. Offspring were tested for PCMV accordingly. All offspring have remained PCMV negative over the whole observation period of 14 months. A completely PCMV-negative pig herd for xenotransplantation has thus been successfully established.
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Affiliation(s)
- Stefanie Egerer
- Center for Innovative Medical Models (CiMM), Institute for Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany
| | | | - Barbara Kessler
- Center for Innovative Medical Models (CiMM), Institute for Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany
| | - Valeri Zakhartchenko
- Center for Innovative Medical Models (CiMM), Institute for Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany
| | - Mayuko Kurome
- Center for Innovative Medical Models (CiMM), Institute for Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany
| | - Bruno Reichart
- Transregional Collaborative Research Center 127, Walter Brendel Centre of Experimental Medicine, LMU Munich, Munich, Germany
| | - Christian Kupatt
- Klinikum Rechts der Isar, Innere Medizin I, TU Munich, Munich, Germany
| | - Nikolai Klymiuk
- Center for Innovative Medical Models (CiMM), Institute for Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany
| | - Eckhard Wolf
- Center for Innovative Medical Models (CiMM), Institute for Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany
| | | | - Andrea Bähr
- Center for Innovative Medical Models (CiMM), Institute for Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany.,Klinikum Rechts der Isar, Innere Medizin I, TU Munich, Munich, Germany
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10
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Denner J. Reduction of the survival time of pig xenotransplants by porcine cytomegalovirus. Virol J 2018; 15:171. [PMID: 30409210 PMCID: PMC6225623 DOI: 10.1186/s12985-018-1088-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 10/28/2018] [Indexed: 02/06/2023] Open
Abstract
Background Xenotransplantation using pig cells, tissues and organs may help to overcome the shortage of human tissues and organs for the treatment of tissue and organ failure. Progress in the prevention of immunological rejection using genetically modified pigs and new, more effective, immunosuppression regimens will allow clinical application of xenotransplantation in near future. However, xenotransplantation may be associated with the transmission of potentially zoonotic porcine microorganisms. Until now the only xenotransplantation-associated transmission was the transmission of the porcine cytomegalovirus (PCMV) into non-human primates. PCMV caused a significant reduction of the survival time of the pig transplant. Main body of the abstract Here the available publications were analysed in order to establish the mechanism how PCMV shortened the survival time of xenotransplants. PCMV is a herpesvirus related to the human cytomegalovirus and the human herpesviruses 6 and 7. These three human herpesviruses can cause serious disease among immunocompromised human individuals, including transplant recipients. It was shown that PCMV predominantly contributes to the reduction of transplant survival in non-human primates by disruption of the coagulation system and by suppression and exhaustion of the immune system. Conclusion Although it is still unknown whether PCMV infects primate cells including human cells, indirect mechanism of the virus infection may cause reduction of the xenotransplant survival in future clinical trials and therefore PCMV has to be eliminated from donor pigs.
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Affiliation(s)
- Joachim Denner
- Robert Koch Fellow, Robert Koch Institute, Nordufer 20, 13353, Berlin, Germany.
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11
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Monocyte derived macrophages as an appropriate model for porcine cytomegalovirus immunobiology studies. Vet Immunol Immunopathol 2018; 197:58-62. [PMID: 29475507 DOI: 10.1016/j.vetimm.2018.01.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 12/21/2017] [Accepted: 01/13/2018] [Indexed: 11/22/2022]
Abstract
Porcine cytomegalovirus (PCMV) causes lifelong latent infections in swine. The pathogen is occasionally associated with inclusion body rhinitis and pneumonia in piglets, reproductive disorders in pregnant sows and respiratory disease complex in older pigs. Immunosuppressive potential of PCMV infection is discussed. Macrophages were recognised as one of target cell types where propagation of virus occurs. The aim of present study was to set up model PCMV infection of monocyte derived macrophages (MDMs) in vitro for PCMV immunobiology research. Obtained results showed that PCMV is able to infect and propagate in MDMs. Possible immunosuppressive effect of PCMV on infected macrophages was evaluated by measurement of immune relevant gene expression in MDMs. Infection decreased expression of IL-8 and TNF-α (pro-inflammatory cytokines) and increased expression of IL-10 (anti-inflammatory cytokine) on mRNA transcription level. Obtained data support hypothesis that higher sensitivity of animals to coinfection with other swine pathogens and its more severe clinical manifestations could potentially be the consequence of PCMV infection.
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Antibody Cross-Reactivity between Porcine Cytomegalovirus (PCMV) and Human Herpesvirus-6 (HHV-6). Viruses 2017; 9:v9110317. [PMID: 29143761 PMCID: PMC5707524 DOI: 10.3390/v9110317] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 10/10/2017] [Accepted: 10/19/2017] [Indexed: 01/16/2023] Open
Abstract
Porcine cytomegalovirus (PCMV) infection is widely prevalent among pigs, and PCMV is one of the viruses which may be transmitted during xenotransplantation using pig cells, tissues, or organs. While human cytomegalovirus (HCMV) is a major risk factor for allotransplantation, it is still unclear whether PCMV is able to infect human cells or pose a risk for xenotransplantation. Previously, it was shown that transmission of PCMV after pig kidney to non-human primate transplantations resulted in a significantly reduced survival time of the transplanted organ. To detect PCMV, PCR-based and immunological methods were used. Screening of pigs by Western blot analyses using recombinant viral proteins revealed up to 100% of the tested animals to be infected. When the same method was applied to screen human sera for PCMV-reactive antibodies, positive Western blot results were obtained in butchers and workers in the meat industry as well as in normal blood donors. To exclude an infection of humans with PCMV, the sera were further investigated. PCMV is closely related to human herpesvirus-6 (HHV-6) and human herpesvirus-7 (HHV-7), and a sequence alignment of glycoprotein B suggests that the antibodies may cross-react with identical epitope sequences. HCMV is not related with PCMV, and no correlation between antibody reactivity against PCMV and HCMV was detected. These data indicate that antibodies against PCMV found in humans are cross-reactive antibodies against HHV-6.
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Denner J. Xenotransplantation and porcine cytomegalovirus. Xenotransplantation 2016; 22:329-35. [PMID: 26381491 DOI: 10.1111/xen.12180] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 06/19/2015] [Indexed: 11/29/2022]
Abstract
Porcine microorganisms may be transmitted to the human recipient when xenotransplantation with pig cells, tissues, and organs will be performed. Most of such microorganisms can be eliminated from the donor pig by specified or designated pathogen-free production of the animals. As human cytomegalovirus causes severe transplant rejection in allotransplantation, considerable concern is warranted on the potential pathogenicity of porcine cytomegalovirus (PCMV) in the setting of xenotransplantation. On the other hand, despite having a similar name, PCMV is different from HCMV. The impact of PCMV infection on pigs is known; however, the influence of PCMV on the human transplant recipient is unclear. However, first transplantations of pig organs infected with PCMV into non-human primates were associated with a significant reduction of the survival time of the transplants. Sensitive detection methods and strategies for elimination of PCMV from donor herds are required.
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New PCR diagnostic systems for the detection and quantification of porcine cytomegalovirus (PCMV). Arch Virol 2016; 161:1159-68. [DOI: 10.1007/s00705-016-2765-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 01/19/2016] [Indexed: 10/22/2022]
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Schleiss MR. Developing a Vaccine against Congenital Cytomegalovirus (CMV) Infection: What Have We Learned from Animal Models? Where Should We Go Next? Future Virol 2013; 8:1161-1182. [PMID: 24523827 DOI: 10.2217/fvl.13.106] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Congenital human cytomegalovirus (HCMV) infection can lead to long-term neurodevelopmental sequelae, including mental retardation and sensorineural hearing loss. Unfortunately, CMVs are highly adapted to their specific species, precluding the evaluation of HCMV vaccines in animal models prior to clinical trials. Several species-specific CMVs have been characterized and developed in models of pathogenesis and vaccine-mediated protection against disease. These include the murine CMV (MCMV), the porcine CMV (PCMV), the rhesus macaque CMV (RhCMV), the rat CMV (RCMV), and the guinea pig CMV (GPCMV). Because of the propensity of the GPCMV to cross the placenta, infecting the fetus in utero, it has emerged as a model of particular interest in studying vaccine-mediated protection of the fetus. In this paper, a review of these various models, with particular emphasis on the value of the model in the testing and evaluation of vaccines against congenital CMV, is provided. Recent exciting developments and advances in these various models are summarized, and recommendations offered for high-priority areas for future study.
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Affiliation(s)
- Mark R Schleiss
- University of Minnesota Medical School Center for Infectious Diseases and Microbiology Translational Research Department of Pediatrics Division of Pediatric Infectious Diseases and Immunology 2001 6 Street SE Minneapolis, MN 55455-3007
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Yang JL, Zhang SH, Liu ZH, Yang R, Huang Y, Wen M. Development and evaluation of a loop-mediated isothermal amplification assay for the rapid detection of porcine cytomegalovirus under field conditions. Virol J 2012; 9:321. [PMID: 23272902 PMCID: PMC3552788 DOI: 10.1186/1743-422x-9-321] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2012] [Accepted: 12/21/2012] [Indexed: 11/15/2022] Open
Abstract
Background Porcine cytomegalovirus (PCMV) induces silent infection in adult pigs but more frequently causes fatal, generalized infection in newborn piglets. This study aimed to develop a new loop-mediated isothermal amplification (LAMP) method for the sensitive, rapid, and inexpensive detection of PCMV under field conditions. Methods Tissue obtained from nine-week-old PCMV-free Landrace pigs or pig samples from postmortem examinations were analyzed. The samples were found to have clinical signs and lesions consistent with inclusion body rhinitis. Six specific primers were designed by targeting the PCMV DNA polymerase (DPOL) DNA. The LAMP reaction was optimized in a water bath. The sensitivity and specificity of LAMP and polymerase chain reaction (PCR) were compared. Results PCMV DNA was amplified at 65°C, and the result could be detected as early as 30 min into the reaction. Positive reactions could be visualized by the naked eye as a color change brought on by the addition of SYBR Green. The sensitivity and specificity of LAMP were found to be similar to those of the PCR. Conclusions LAMP is a high-throughput technique for the detection of PCMV and has a high specificity, sensitivity and simplicity; these factors make it suitable for detection of PCMV under field conditions.
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Affiliation(s)
- Jin-Long Yang
- Animal Science College of Guizhou University, Guiyang, Guizhou, China.
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Sekiguchi M, Shibahara T, Miyazaki A, Tajima T, Shimizu S, Kabali E, Takano Y, Sasaki Y, Kubo M. In situ hybridization and immunohistochemistry for the detection of porcine cytomegalovirus. J Virol Methods 2011; 179:272-5. [PMID: 22008295 DOI: 10.1016/j.jviromet.2011.10.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Revised: 09/27/2011] [Accepted: 10/03/2011] [Indexed: 11/26/2022]
Abstract
To establish in situ hybridization and immunohistochemistry based-assays for the detection of porcine cytomegalovirus, routinely processed renal tissue sections from 34 diseased piglets suspected of having the infection were obtained and examined. Using hematoxylin and eosin, porcine cytomegalovirus inclusion bodies were found in the nucleus of renal epithelial cells and capillary endothelial cells in the renal medulla in 30 cases. Inclusion bodies corresponding to porcine cytomegalovirus mRNA after in situ hybridization or porcine cytomegalovirus antigens after immunohistochemistry were easily determined. The cells were characterized by cytomegaly and basophilic intranuclear inclusion bodies. Using in situ hybridization, porcine cytomegalovirus mRNA were clearly detected in the nucleus and cytoplasm of the cells in 28 of the 30 (93.3%) cases. Using immunohistochemistry, porcine cytomegalovirus antigens were clearly detected in the cytoplasm of the cells in 21 of the 30 (70.0%) cases. Higher specificities and increased intensity of staining was observed with minimal background using in situ hybridization and immunohistochemistry compared with hematoxylin and eosin. Thus, the two established methods are useful and helpful tools for detecting the presence of a porcine cytomegalovirus infection.
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Affiliation(s)
- Maki Sekiguchi
- Chuou Livestock Hygiene Service Center, 497 Iwatomi, Sakura, Chiba 285-0072, Japan
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Neuropathogenesis of congenital cytomegalovirus infection: disease mechanisms and prospects for intervention. Clin Microbiol Rev 2009; 22:99-126, Table of Contents. [PMID: 19136436 DOI: 10.1128/cmr.00023-08] [Citation(s) in RCA: 323] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Congenital cytomegalovirus (CMV) infection is the leading infectious cause of mental retardation and hearing loss in the developed world. In recent years, there has been an improved understanding of the epidemiology, pathogenesis, and long-term disabilities associated with CMV infection. In this review, current concepts regarding the pathogenesis of neurological injury caused by CMV infections acquired by the developing fetus are summarized. The pathogenesis of CMV-induced disabilities is considered in the context of the epidemiology of CMV infection in pregnant women and newborn infants, and the clinical manifestations of brain injury are reviewed. The prospects for intervention, including antiviral therapies and vaccines, are summarized. Priorities for future research are suggested to improve the understanding of this common and disabling illness of infancy.
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Thumbi DK, Arif BM, Krell PJ. Susceptibility of Autographa californica multiple nucleopolyhedrovirus to inhibitors of DNA replication. J Virol Methods 2007; 146:209-17. [PMID: 17706798 DOI: 10.1016/j.jviromet.2007.07.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2007] [Revised: 06/26/2007] [Accepted: 07/04/2007] [Indexed: 10/22/2022]
Abstract
The objectives of this study were to develop methods to evaluate the susceptibility of the type baculovirus AcMNPV to various antiviral compounds and to select potential inhibitors for investigating baculovirus DNA replication. In concert with the classical cytopathic effects (CPE) and cytotoxicity inhibition assays, two approaches, which could be amenable for high throughput application for evaluating several classes of known antiviral compounds were developed. (i) An indirect approach based on spectrofluorimetric analysis of EGFP expression in Sf21 cells infected with a recombinant AcMNPV (AcEGFP) and (ii) a direct DNA quantitative assay based on quantitative real time PCR (qPCR). Initial CPE results suggested that of 21 compounds tested, aphidicolin, abacavir, camptothecin, (E)-5-(2-bromovinyl)-2'-deoxyuridine (BVDU), l-mimosine, hydroxyurea and phosphonoacetic acid (PAA) were selective inhibitors of AcMNPV replication. Consistent with the CPE results, the EGFP fluorescence and the qPCR of viral DNA accumulation exhibited a dose dependent depression of EGFP expression and DNA accumulation, respectively, in infected cells exposed to them. The inhibitory effects of aphidicolin, abacavir, l-mimosine and hydroxyurea on AcMNPV DNA replication were reversible. Taken together, both spectrofluorimetric and qPCR assays are suitable and rapid quantitative approaches to investigate inhibitors of baculovirus DNA replication in infected cells.
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Affiliation(s)
- David K Thumbi
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ont. N1G 2W1, Canada
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Schleiss MR. Nonprimate models of congenital cytomegalovirus (CMV) infection: gaining insight into pathogenesis and prevention of disease in newborns. ILAR J 2006; 47:65-72. [PMID: 16391432 DOI: 10.1093/ilar.47.1.65] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Congenital and perinatal infections with cytomegalovirus (CMV) are responsible for considerable short- and long- term morbidity in infants. CMV is the most common congenital viral infection in the developed world, and is a common cause of neurodevelopmental injury, including mental retardation and sensorineural hearing loss (SNHL). Antiviral therapy has been shown to be valuable in ameliorating the severity of SNHL, but CMV disease control in newborns ultimately depends on successful development of a vaccine. Because CMVs are extremely species specific, preclinical evaluation of vaccines must be performed in animal models using the appropriate CMV of the animal being studied. Several small animal models available for CMV vaccine and pathogenesis research are described. The discussion focuses on the guinea pig model because guinea pig cytomegalovirus (GPCMV), which crosses the placenta and causes infection in utero, is uniquely useful. Examination of vaccines in the GPCMV and other nonprimate models should provide insights into the determinants of the host response that protect the fetus, and may help to prioritize potential vaccine strategies for use in human clinical trials related to this important public health problem.
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Affiliation(s)
- Mark R Schleiss
- Division of Pediatric Infectious Diseases, University of Minnesota Children's Hospital, and School of Medicine, Department of Pediatrics, Minneapolis, MN, USA
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Griffiths PD. Antivirals in the transplant setting. Antiviral Res 2006; 71:192-200. [PMID: 16793148 DOI: 10.1016/j.antiviral.2006.04.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2006] [Revised: 04/27/2006] [Accepted: 04/28/2006] [Indexed: 12/12/2022]
Abstract
Over the past quarter of a century, antiviral drugs have moved from an experimental adventure in transplant patients to a situation where they are used routinely to prevent diseases caused by several viruses. Furthermore, they have significantly reduced several medical complications of transplantation, such as graft rejection, thereby implicating viruses as components of their pathogenesis. By controlling these major complication, the development of these antiviral drugs and their prodrugs, has therefore greatly facilitated the clinical expansion of transplantation, allowing life saving procedures to be offered to more patients who could potentially benefit. This article will briefly summaries which viruses are important following transplantation and outline the evidence-base from randomized controlled clinical trails for the deployment of antiviral drugs to prevent viral diseases.
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Affiliation(s)
- Paul D Griffiths
- Centre for Virology, Department of Infection, Royal Free and University College Medical School, Rowland Hill Street, London NW3 2PF, United Kingdom.
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Abstract
Infectious risk remains an important consideration in the clinical application of xenotransplantation. Vascularized xenografts create unique immunological niches in which bidirectional transmission of pathogens between donor and recipient may occur. Enhanced replication of many pathogens is stimulated by the immune responses induced by transplantation and by the immune suppression used to prevent graft rejection. Herpesviruses are the prototype viruses that are activated during immunosuppression. Quantitative diagnostic molecular assays have been developed for the known herpesviruses causing infection in pigs. Recent data suggest that some herpesviral infections, such as porcine cytomegalovirus, may be excluded from swine used as source animals by careful breeding, while others will require novel strategies for control. This review focuses on porcine and baboon herpesviruses in pig-to-non-human primate solid organ xenotransplantation including direct effects (tissue damage), indirect effects (coagulopathy, rejection), and possible approaches to these infections.
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Affiliation(s)
- Nicolas J Mueller
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zürich, CH-8091 Zürich, Switzerland.
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Buhler LH. Xenotransplantation literature update may-june 2004. Xenotransplantation 2004; 11:476-8. [PMID: 15303985 DOI: 10.1111/j.1399-3089.2004.00164.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Leo H Buhler
- Xenotransplantation, Department of Surgery, University Hospital Geneva, Geneva, Switzerland.
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