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Otabi H, Miura H, Uryu H, Kobayashi-Harada R, Abe K, Nakano K, Umeyama K, Hasegawa K, Tsukahara T, Nagashima H, Inoue R. Development of a panel for detection of pathogens in xenotransplantation donor pigs. Xenotransplantation 2023; 30:e12825. [PMID: 37771249 DOI: 10.1111/xen.12825] [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: 05/01/2023] [Revised: 08/11/2023] [Accepted: 08/29/2023] [Indexed: 09/30/2023]
Abstract
There have been high expectations in recent years of using xenotransplantation and regenerative medicine to treat humans, and pigs have been utilized as the donor model. Pigs used for these clinical applications must be microbiologically safe, that is, free of infectious pathogens, to prevent infections not only in livestock, but also in humans. Currently, however, the full spectrum of pathogens that can infect to the human host or cause disease in transplanted porcine organs/cells has not been fully defined. In the present study, we thus aimed to develop a larger panel for the detection of pathogens that could potentially infect xenotransplantation donor pigs. Our newly developed panel, which consisted of 76 highly sensitive PCR detection assays, was able to detect 41 viruses, 1 protozoa, and a broad range of bacteria (by use of universal 16S rRNA primers). The applicability of this panel was validated using blood samples from uterectomy-born piglets, and pathogens suspected to be vertically transmitted from sows to piglets were successfully detected. We estimate that, at least for viruses and bacteria, the number of target pathogens detected by the developed screening panel should suffice to meet the microbiological safety levels required worldwide for xenotransplantation and/or regenerative therapy. This panel provides greater diagnosis options to produce donor pigs so that it would render unnecessary to screen for all pathogens listed. Instead, the new panel could be utilized to detect only required pathogens within a given geographic range where the donor pigs for xenotransplantation have been and/or are being developed.
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Affiliation(s)
- Hikari Otabi
- Laboratory of Animal Science, Department of Applied Biological Sciences, Faculty of Agriculture, Setsunan University, Osaka, Japan
| | - Hiroto Miura
- Laboratory of Animal Science, Department of Applied Biological Sciences, Faculty of Agriculture, Setsunan University, Osaka, Japan
| | - Haruka Uryu
- Laboratory of Animal Science, Department of Applied Biological Sciences, Faculty of Agriculture, Setsunan University, Osaka, Japan
- Laboratory of Animal Science, Kyoto Prefectural University, Kyoto, Japan
| | | | - Kanako Abe
- Laboratory of Animal Science, Department of Applied Biological Sciences, Faculty of Agriculture, Setsunan University, Osaka, Japan
| | - Kazuaki Nakano
- Meiji University International Institute for Bio-Resource Research, Kawasaki, Japan
| | - Kazuhiro Umeyama
- Meiji University International Institute for Bio-Resource Research, Kawasaki, Japan
| | - Koki Hasegawa
- Laboratory of Medical Bioengineering, Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki, Japan
| | | | - Hiroshi Nagashima
- Meiji University International Institute for Bio-Resource Research, Kawasaki, Japan
- Laboratory of Medical Bioengineering, Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki, Japan
| | - Ryo Inoue
- Laboratory of Animal Science, Department of Applied Biological Sciences, Faculty of Agriculture, Setsunan University, Osaka, Japan
- Laboratory of Animal Science, Kyoto Prefectural University, Kyoto, Japan
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2
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Groenendaal H, Costard S, Ballard R, Bienhoff S, Challen DC, Dominguez BJ, Kern DR, Miller D, Noordergraaf J, Rudenko L, Schuurman HJ, Spizzo T, Sturos M, Zollers B, Fishman JA. Expert opinion on the identification, risk assessment, and mitigation of microorganisms and parasites relevant to xenotransplantation products from pigs. Xenotransplantation 2023; 30:e12815. [PMID: 37616183 DOI: 10.1111/xen.12815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 05/18/2023] [Accepted: 07/13/2023] [Indexed: 08/26/2023]
Abstract
Xenotransplantation has the potential to address shortages of organs available for clinical transplantation, but concerns exist regarding potential risks posed by porcine microorganisms and parasites (MP) to the health of human recipients. In this study, a risk-based framework was developed, and expert opinion was elicited to evaluate porcine MP based on swine exposure and risk to human health. Experts identified 255 MP to include in the risk assessment. These were rated by experts for five criteria regarding potential swine exposure in the USA and human health risks. MP were subsequently categorized into three risk mitigation groups according to pre-defined rules: disqualifying porcine MP (due to their pathogenic potential, n = 130); non-disqualifying porcine MP (still relevant to consider for biosecurity or monitoring efforts, n = 40); and alert/watch list (not reported in the USA or MP not in swine, n = 85). Most disqualifying (n = 126) and non-disqualifying (n = 36) porcine MP can effectively be eliminated with high biosecurity programs. This approach supports surveillance and risk mitigation strategies for porcine MP in swine produced for xenotransplantation, such as documentation of freedom from porcine MP, or use of porcine MP screening, monitoring, or elimination options. To the authors' knowledge, this is the first effort to comprehensively identify all relevant porcine MP systematically and transparently evaluate the risk of infection of both donor animals and immunosuppressed human recipients, and the potential health impacts for immunosuppressed human recipients from infected xenotransplantation products from pigs.
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Affiliation(s)
| | | | - Reid Ballard
- Colorado State University, Fort Collins, Colorado, USA
| | | | | | | | | | - Dan Miller
- Excorp Biomedical International Pte. Ltd., Singapore
| | | | - Larisa Rudenko
- BioPolicy Solutions, LLC, Ventura, California, USA; Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | | | - Tom Spizzo
- Spring Point Project, Minneapolis, Minnesota, USA
| | - Matthew Sturos
- Veterinary Diagnostic Laboratory, University of Minnesota, St. Paul, Minnesota, USA
| | - Bill Zollers
- Argenta Clinical US, New Brunswick, New Jersey, USA
| | - Jay A Fishman
- Transplant Center and Division of Infectious Diseases, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
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Rivera NT, Baran DA. Expanding heart transplantation in 2022 and beyond. Curr Opin Cardiol 2023; 38:130-135. [PMID: 36598449 DOI: 10.1097/hco.0000000000001023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
PURPOSE OF REVIEW Despite advances in the technology of mechanical circulatory support, the need for heart transplantation continues to grow. The longevity of heart transplants continues to be superior to mechanical solutions, though the short-term differences are shrinking. In this review, we cover three timely developments and summarize the recent literature. RECENT FINDINGS After stagnant rates of heart transplant activity for some years, recently, transplant volume has increased. The developments that have ignited interest have been the use of hepatitis C infected donors, which can now be safely transplanted with the advent of curative oral regimens, and the worldwide use of donors following withdrawal of life support as opposed to traditional brain death donors. In addition, the recent experience of human cardiac xenotransplantation has been very exciting, and though it is not of clinical utility yet, it holds the promise for a virtually unlimited supply of organs at some time in the future. SUMMARY Much work remains to be done, but together, all three of these developments are exciting and important to be aware of in the future. Each will contribute to additional donors for human heart transplantation and hopefully will alleviate suffering and death on the waiting list.
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Denner J. Xenotransplantation of pig islet cells: Potential adverse impact of virus infections on their functionality and insulin production. Xenotransplantation 2022; 30:e12789. [PMID: 36495163 DOI: 10.1111/xen.12789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 09/09/2022] [Accepted: 10/26/2022] [Indexed: 12/14/2022]
Affiliation(s)
- Joachim Denner
- Institute of Virology Free University Berlin Berlin Germany
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5
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Virus Safety of Xenotransplantation. Viruses 2022; 14:v14091926. [PMID: 36146732 PMCID: PMC9503113 DOI: 10.3390/v14091926] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 08/29/2022] [Accepted: 08/29/2022] [Indexed: 01/06/2023] Open
Abstract
The practice of xenotransplantation using pig islet cells or organs is under development to alleviate the shortage of human donor islet cells or organs for the treatment of diabetes or organ failure. Multiple genetically modified pigs were generated to prevent rejection. Xenotransplantation may be associated with the transmission of potentially zoonotic porcine viruses. In order to prevent this, we developed highly sensitive PCR-based, immunologicals and other methods for the detection of numerous xenotransplantation-relevant viruses. These methods were used for the screening of donor pigs and xenotransplant recipients. Of special interest are the porcine endogenous retroviruses (PERVs) that are integrated in the genome of all pigs, which are able to infect human cells, and that cannot be eliminated by methods that other viruses can. We showed, using droplet digital PCR, that the number of PERV proviruses is different in different pigs (usually around 60). Furthermore, the copy number is different in different organs of a single pig, indicating that PERVs are active in the living animals. We showed that in the first clinical trials treating diabetic patients with pig islet cells, no porcine viruses were transmitted. However, in preclinical trials transplanting pig hearts orthotopically into baboons, porcine cytomegalovirus (PCMV), a porcine roseolovirus (PCMV/PRV), and porcine circovirus 3 (PCV3), but no PERVs, were transmitted. PCMV/PRV transmission resulted in a significant reduction of the survival time of the xenotransplant. PCMV/PRV was also transmitted in the first pig heart transplantation to a human patient and possibly contributed to the death of the patient. Transmission means that the virus was detected in the recipient, however it remains unclear whether it can infect primate cells, including human cells. We showed previously that PCMV/PRV can be eliminated from donor pigs by early weaning. PERVs were also not transmitted by inoculation of human cell-adapted PERV into small animals, rhesus monkey, baboons and cynomolgus monkeys, even when pharmaceutical immunosuppression was applied. Since PERVs were not transmitted in clinical, preclinical, or infection experiments, it remains unclear whether they should be inactivated in the pig genome by CRISPR/Cas. In summary, by using our sensitive methods, the safety of xenotransplantation can be ensured.
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Holdcraft RW, Graham MJ, Bemrose MA, Mutch LA, Martis PC, Janecek JL, Hall RD, Smith BH, Gazda LS. Long-term efficacy and safety of porcine islet macrobeads in nonimmunosuppressed diabetic cynomolgus macaques. Xenotransplantation 2022; 29:e12747. [PMID: 35384085 DOI: 10.1111/xen.12747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 10/05/2021] [Accepted: 03/10/2022] [Indexed: 11/26/2022]
Abstract
Although human islet transplantation has proven to provide clinical benefits, especially the near complete amelioration of hypoglycemia, the supply of human islets is limited and insufficient to meet the needs of all people that could benefit from islet transplantation. Porcine islets, secreting insulin nearly identical to that of human insulin, have been proposed as a viable supply of unlimited islets. Further, encapsulation of the porcine islets has been shown to reduce or eliminate the use of immunosuppressive therapy that would be required to prevent rejection of the foreign islet tissue. The goal of the current study was to determine the long-term safety and efficacy of agarose encapsulated porcine islets (macrobeads) in diabetic cynomolgus macaques, in a study emulating a proposed IND trial in which daily exogenous insulin therapy would be reduced by 50% with no loss of glucose regulation. Four of six animals implanted with macrobeads demonstrated ≥ 30% reduction in insulin requirements in year 1 of follow-up. Animals were followed for 2, 3.5, and 7.4 years with no serious adverse events, mortality or evidence of pathogen transmission. This study supports the continued pursuit of encapsulated porcine islet therapy as a promising treatment option for diabetes mellitus.
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Affiliation(s)
| | - Melanie J Graham
- Preclinical Research Center, University of Minnesota, St. Paul, Minnesota, USA
| | | | - Lucas A Mutch
- Preclinical Research Center, University of Minnesota, St. Paul, Minnesota, USA
| | | | - Jody L Janecek
- Preclinical Research Center, University of Minnesota, St. Paul, Minnesota, USA
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7
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Halecker S, Metzger J, Strube C, Krabben L, Kaufer B, Denner J. Virological and Parasitological Characterization of Mini-LEWE Minipigs Using Improved Screening Methods and an Overview of Data on Various Minipig Breeds. Microorganisms 2021; 9:microorganisms9122617. [PMID: 34946218 PMCID: PMC8706741 DOI: 10.3390/microorganisms9122617] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/13/2021] [Accepted: 12/15/2021] [Indexed: 01/04/2023] Open
Abstract
Minipigs play an important role in biomedical research and have also been used as donor animals in xenotransplantation. To serve as a donor in xenotransplantation, the animals must be free of potential zoonotic viruses, bacteria and parasites. Porcine endogenous retroviruses (PERVs) are integrated in the genome of all pigs and cannot be eliminated as most of the other pig viruses can. PERV-A and PERV-B infect human cells in cell culture and are integrated in all pigs, whereas PERV-C infects only pig cells and it is found in many, but not all pigs. Minipigs are known for a high prevalence of recombinant PERV-A/C viruses able to infect human cells (Denner and Schuurman, Viruses, 2021;13:1869). Here, Mini-LEWE minipigs are screened for the first time for pig viruses including PERV. Peripheral blood mononuclear cells (PBMCs) from 10 animals were screened using PCR-based methods (PCR, RT-PCR, and real-time PCR). In comparison with our previous screening assays, numerous improvements were introduced, e.g., the usage of gene blocks as a PCR standard and foreign RNA to control reverse transcription in RT-PCR. Using these improved detection methods, Mini-LEWE pigs were found to be negative for porcine cytomegalovirus (PCMV), porcine lymphotropic herpesviruses (PLHV-1, -2 and -3), porcine circoviruses (PCV1, 2, 3 and 4), porcine parvovirus (PPV) and hepatitis E virus (HEV). All animals carried PERV-A, PERV-B and PERV-C in their genome. PERV-A/C was not found. In contrast to all other minipig breeds (Göttingen minipigs, Aachen minipigs, Yucatan micropig, Massachusetts General Hospital miniature pigs), Mini-LEWE minipigs have less viruses and no PERV-A/C. Parasitological screening showed that none of the Mini-LEWE minipigs harbored ecto- and gastrointestinal parasites, but at least one animal tested positive for anti-Toxoplasma gondii antibodies.
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Affiliation(s)
- Sabrina Halecker
- Institute of Virology, Freie Universität Berlin, 14163 Berlin, Germany; (S.H.); (L.K.); (B.K.)
| | - Julia Metzger
- Research Group Veterinary Functional Genomics, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany;
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Hannover, 30559 Hannover, Germany
| | - Christina Strube
- Institute for Parasitology, Centre for Infection Medicine, University of Veterinary Medicine Hannover, 30559 Hannover, Germany;
| | - Ludwig Krabben
- Institute of Virology, Freie Universität Berlin, 14163 Berlin, Germany; (S.H.); (L.K.); (B.K.)
| | - Benedikt Kaufer
- Institute of Virology, Freie Universität Berlin, 14163 Berlin, Germany; (S.H.); (L.K.); (B.K.)
| | - Joachim Denner
- Institute of Virology, Freie Universität Berlin, 14163 Berlin, Germany; (S.H.); (L.K.); (B.K.)
- Correspondence: ; Tel.: +49-30-8386-3059
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8
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Denner J. Porcine Endogenous Retroviruses and Xenotransplantation, 2021. Viruses 2021; 13:v13112156. [PMID: 34834962 PMCID: PMC8625113 DOI: 10.3390/v13112156] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/06/2021] [Accepted: 10/20/2021] [Indexed: 12/25/2022] Open
Abstract
Porcine endogenous retroviruses (PERVs) are integrated in the genome of all pigs, and some of them are able to infect human cells. Therefore, PERVs pose a risk for xenotransplantation, the transplantation of pig cells, tissues, or organ to humans in order to alleviate the shortage of human donor organs. Up to 2021, a huge body of knowledge about PERVs has been accumulated regarding their biology, including replication, recombination, origin, host range, and immunosuppressive properties. Until now, no PERV transmission has been observed in clinical trials transplanting pig islet cells into diabetic humans, in preclinical trials transplanting pig cells and organs into nonhuman primates with remarkable long survival times of the transplant, and in infection experiments with several animal species. Nevertheless, in order to prevent virus transmission to the recipient, numerous strategies have been developed, including selection of PERV-C-free animals, RNA interference, antiviral drugs, vaccination, and genome editing. Furthermore, at present there are no more experimental approaches to evaluate the full risk until we move to the clinic.
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Affiliation(s)
- Joachim Denner
- Department of Veterinary Medicine, Institute of Virology, Free University Berlin, 14163 Berlin, Germany
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9
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High Prevalence of Recombinant Porcine Endogenous Retroviruses (PERV-A/Cs) in Minipigs: A Review on Origin and Presence. Viruses 2021; 13:v13091869. [PMID: 34578447 PMCID: PMC8473008 DOI: 10.3390/v13091869] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/14/2021] [Accepted: 09/15/2021] [Indexed: 12/17/2022] Open
Abstract
Minipigs play an important role in biomedical research and they have also been used as donor animals for preclinical xenotransplantations. Since zoonotic microorganisms including viruses can be transmitted when pig cells, tissues or organs are transplanted, virus safety is an important feature in xenotransplantation. Whereas most porcine viruses can be eliminated from pig herds by different strategies, this is not possible for porcine endogenous retroviruses (PERVs). PERVs are integrated in the genome of pigs and some of them release infectious particles able to infect human cells. Whereas PERV-A and PERV-B are present in all pigs and can infect cells from humans and other species, PERV-C is present in most, but not all pigs and infects only pig cells. Recombinant viruses between PERV-A and PERV-C have been found in some pigs; these recombinants infect human cells and are characterized by high replication rates. PERV-A/C recombinants have been found mainly in minipigs of different origin. The possible reasons of this high prevalence of PERV-A/C in minipigs, including inbreeding and higher numbers and expression of replication-competent PERV-C in these animals, are discussed in this review. Based on these data, it is highly recommended to use only pig donors in clinical xenotransplantation that are negative for PERV-C.
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10
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Reichart B, Längin M, Denner J, Schwinzer R, Cowan PJ, Wolf E. Pathways to Clinical Cardiac Xenotransplantation. Transplantation 2021; 105:1930-1943. [PMID: 33350675 DOI: 10.1097/tp.0000000000003588] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Heart transplantation is the only long-lasting lifesaving option for patients with terminal cardiac failure. The number of available human organs is however far below the actual need, resulting in substantial mortality of patients while waiting for a human heart. Mechanical assist devices are used to support cardiac function but are associated with a high risk of severe complications and poor quality of life for the patients. Consistent success in orthotopic transplantation of genetically modified pig hearts into baboons indicates that cardiac xenotransplantation may become a clinically applicable option for heart failure patients who cannot get a human heart transplant. In this overview, we project potential paths to clinical cardiac xenotransplantation, including the choice of genetically modified source pigs; associated requirements of microbiological, including virological, safety; optimized matching of source pig and recipient; and specific treatments of the donor heart after explantation and of the recipients. Moreover, selection of patients and the regulatory framework will be discussed.
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Affiliation(s)
- Bruno Reichart
- Walter Brendel Center for Experimental Medicine, LMU Munich, Munich, Germany
| | - Matthias Längin
- Department of Anaesthesiology, University Hospital, LMU Munich, Munich, Germany
| | - Joachim Denner
- Institute of Virology, Free University Berlin, Berlin, Germany
| | - Reinhard Schwinzer
- Department of General-, Visceral-, and Transplantation Surgery, Transplant Laboratory, Hannover Medical School, Hannover, Germany
| | - Peter J Cowan
- Immunology Research Centre, St. Vincent's Hospital Melbourne, Victoria, Australia
- Department of Medicine, University of Melbourne, VIC, Australia
| | - Eckhard Wolf
- Institute of Molecular Animal Breeding and Biotechnology, Gene Center, LMU Munich, Munich, Germany
- Department of Veterinary Sciences, and Center for Innovative Medical Models (CiMM), LMU Munich, Munich, Germany
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11
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Denner J. Porcine Lymphotropic Herpesviruses (PLHVs) and Xenotranplantation. Viruses 2021; 13:1072. [PMID: 34199939 PMCID: PMC8229715 DOI: 10.3390/v13061072] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/01/2021] [Accepted: 06/03/2021] [Indexed: 12/23/2022] Open
Abstract
Porcine lymphotropic herpesviruses -1, -2 and -3 (PLHV-1, PLHV-2 and PLHV-3) are gammaherpesviruses which are widespread in pigs. They are closely related to the Epstein-Barr virus (EBV) and Kaposi sarcoma herpesvirus, both of which cause severe diseases in humans. PLHVs are also related to bovine and ovine gammaherpesviruses, which are apathogenic in the natural host, but cause severe diseases after transmission into other species. Until now, no association between PLHVs and any pig diseases had been described. However, PLHV-1 causes a post-transplantation lymphoproliferative disorder (PTLD) after experimental transplantations in minipigs. This disorder is similar to human PTLD, a serious complication of solid human organ transplantation linked to EBV. Xenotransplantation using pig cells, tissues and organs is under development in order to alleviate the shortage of human transplants. Meanwhile, remarkable survival times of pig xenotransplants in non-human primates have been achieved. In these preclinical trials, another pig herpesvirus, the porcine cytomegalovirus (PCMV), a roseolovirus, was shown to significantly reduce the survival time of pig xenotransplants in baboons and other non-human primates. Although PLHV-1 was found in genetically modified donor pigs used in preclinical xenotransplantation, it was, in contrast to PCMV, not transmitted to the recipient. Nevertheless, it seems important to use PLHV-free donor pigs in order to achieve safe xenotransplantation.
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Affiliation(s)
- Joachim Denner
- Institute of Virology, Free University, 14163 Berlin, Germany
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12
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Niu D, Ma X, Yuan T, Niu Y, Xu Y, Sun Z, Ping Y, Li W, Zhang J, Wang T, Church GM. Porcine genome engineering for xenotransplantation. Adv Drug Deliv Rev 2021; 168:229-245. [PMID: 32275950 DOI: 10.1016/j.addr.2020.04.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 03/28/2020] [Accepted: 04/06/2020] [Indexed: 02/06/2023]
Abstract
The extreme shortage of human donor organs for treatment of patients with end-stage organ failures is well known. Xenotransplantation, which might provide unlimited organ supply, is a most promising strategy to solve this problem. Domestic pigs are regarded as ideal organ-source animals owing to similarity in anatomy, physiology and organ size to humans as well as high reproductive capacity and low maintenance cost. However, several barriers, which include immune rejection, inflammation and coagulative dysfunctions, as well as the cross-species transmission risk of porcine endogenous retrovirus, blocked the pig-to-human xenotransplantation. With the rapid development of genome engineering technologies and the potent immunosuppressive medications in recent years, these barriers could be eliminated through genetic modification of pig genome together with the administration of effective immunosuppressants. A number of candidate genes involved in the regulation of immune response, inflammation and coagulation have been explored to optimize porcine xenograft survival in non-human primate recipients. PERV inactivation in pigs has also been accomplished to firmly address the safety issue in pig-to-human xenotransplantation. Many encouraging preclinical milestones have been achieved with some organs surviving for years. Therefore, the clinical trials of some promising organs, such as islet, kidney and heart, are aimed to be launched in the near future.
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Affiliation(s)
- Dong Niu
- Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, College of Animal Science and Technology & College of Veterinary Medicine of Zhejiang A&F University, Hangzhou, P.R. China
| | - Xiang Ma
- Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, College of Animal Science and Technology & College of Veterinary Medicine of Zhejiang A&F University, Hangzhou, P.R. China
| | - Taoyan Yuan
- Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang 310021, China
| | - Yifan Niu
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, Jiangsu 211300, China
| | - Yibin Xu
- College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Zhongxin Sun
- Cosmetic & Plastic Surgery Department, Hangzhou First People's Hospital, Hangzhou, Zhejiang 310006, China
| | - Yuan Ping
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Weifen Li
- College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jufang Zhang
- Cosmetic & Plastic Surgery Department, Hangzhou First People's Hospital, Hangzhou, Zhejiang 310006, China.
| | - Tao Wang
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, Jiangsu 211300, China.
| | - George M Church
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA 02138, USA.
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13
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Matsumoto S, Wynyard S, Giovannangelo M, Hemdev SL, Abalovich A, Carulla ME, Wechsler CJ. Long-term follow-up for the microbiological safety of clinical microencapsulated neonatal porcine islet transplantation. Xenotransplantation 2020; 27:e12631. [PMID: 32691966 DOI: 10.1111/xen.12631] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/28/2020] [Accepted: 06/29/2020] [Indexed: 12/13/2022]
Abstract
Enrollment in three clinical trials for microencapsulated neonatal porcine islet xenotransplantation to treat unstable type 1 diabetic patients concluded in November 2014. In this study, we report a long-term follow-up assessment of microbiological safety for these trials. Thirty-eight type 1 diabetic patients received microencapsulated neonatal porcine islet transplants. Islets were isolated and prepared from the pancreata of New Zealand (NZ) based designated pathogen-free (DPF) pigs under GMP conditions. Blood samples of thirty-six patients were collected from 5 to 7 years post-first transplant and were tested by real-time PCR for porcine circovirus-1 (PCV1), porcine circovirus-2 (PCV2), porcine lymphotropic herpesvirus 1 (PLHV1), porcine lymphotropic herpesvirus 2 (PLHV2), and porcine cytomegalovirus (PCMV). To detect porcine endogenous retrovirus (PERV), specific real-time PCR and product enhanced reserve transcriptase (PERT) assays were performed. PCV1, PCV2, PLHV1, PLHV2, PCMV, PERV, and reverse transcriptase (RT) activity remained undetected in all tested samples indicating no viral transmission. Except for one patient that died due to complications unrelated to the transplant, there were no significant adverse events. Microbiological safety was demonstrated for microencapsulated neonatal porcine islet xenotransplantation from 5-7 years post-transplantation consistent with earlier reports.
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Affiliation(s)
- Shinichi Matsumoto
- Diatranz Otsuka Ltd, Auckland, New Zealand.,Otsuka Pharmaceutical Factory Inc., Naruto, Japan
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14
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Wynyard S. Challenges and practical realities of long‐term patient follow‐up in three xeno‐islet clinical trials: The experience in pig islet xenotransplantation trials in New Zealand and Argentina. Xenotransplantation 2020; 27:e12605. [DOI: 10.1111/xen.12605] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 04/24/2020] [Indexed: 12/14/2022]
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15
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Schuurman H, Hoogendoorn K. Solid organ xenotransplantation at the interface between research and clinical development: Regulatory aspects. Xenotransplantation 2020; 27:e12608. [DOI: 10.1111/xen.12608] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 05/04/2020] [Indexed: 12/20/2022]
Affiliation(s)
| | - Karin Hoogendoorn
- Interdivisional GMP Facility Hospital Pharmacy Leiden University Medical Center Leiden The Netherlands
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16
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Denner J. By definition…. Xenotransplantation 2020; 27:e12599. [PMID: 32347614 DOI: 10.1111/xen.12599] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 02/21/2020] [Accepted: 03/04/2020] [Indexed: 11/29/2022]
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17
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Denner J. Sensitive detection systems for infectious agents in xenotransplantation. Xenotransplantation 2020:e12594. [PMID: 32304138 DOI: 10.1111/xen.12594] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 03/25/2020] [Indexed: 12/18/2022]
Abstract
Xenotransplantation of pig cells, tissues, or organs may be associated with transmission of porcine microorganisms, first of all of viruses, to the transplant recipient, potentially inducing a disease (zoonosis). I would like to define detection systems as the complex of sample generation, sample preparation, sample origin, time of sampling, and the necessary negative and positive controls along with the specific detection methods, either PCR-based, cell-based, or immunological methods. Some xenotransplantation-relevant viruses have already been defined; others are still unknown. The PCR-based methods include PCR and real-time PCR for DNA viruses, and RT-PCR and real-time RT-PCR for RNA viruses as well as for virus expression studies at the RNA level. Furthermore, droplet digital PCR (ddPCR) can be used for the determination of virus and provirus copies. To detect expression at the protein level, immunofluorescence, immunohistochemistry, and Western blot analyses can be used. To detect virus production and to detect infectious viruses, electron microscopy and infection assays can be used. Furthermore, immunological methods such as Western blot analysis or ELISA can be used to detect virus-specific antibodies. Detection of antiviral antibodies is a reliable and sensitive indirect detection method. For these immunological methods, purified viruses, recombinant viral proteins, or synthetic peptides are used as antigens and control sera and control antigens are needed. All these methods have been used in the past for the characterization of different pig breeds including genetically modified pigs generated for xenotransplantation and for the screening of recipients in preclinical and clinical xenotransplantations. Whereas in preclinical trials a few porcine viruses have been transmitted to the non-human primate recipients, in first clinical trials no such transmissions to humans were observed. Further improvement of the detection systems and their application in virus elimination programs will lead to clean donor animals and a safe xenotransplantation.
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18
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Toda S, Fattah A, Asawa K, Nakamura N, N. Ekdahl K, Nilsson B, Teramura Y. Optimization of Islet Microencapsulation with Thin Polymer Membranes for Long-Term Stability. MICROMACHINES 2019; 10:mi10110755. [PMID: 31698737 PMCID: PMC6915491 DOI: 10.3390/mi10110755] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Revised: 10/30/2019] [Accepted: 11/04/2019] [Indexed: 12/23/2022]
Abstract
Microencapsulation of islets can protect against immune reactions from the host immune system after transplantation. However, sufficient numbers of islets cannot be transplanted due to the increase of the size and total volume. Therefore, thin and stable polymer membranes are required for the microencapsulation. Here, we undertook the cell microencapsulation using poly(ethylene glycol)-conjugated phospholipid (PEG-lipid) and layer-by-layer membrane of multiple-arm PEG. In order to examine the membrane stability, we used different molecular weights of 4-arm PEG (10k, 20k and 40k)-Mal to examine the influence on the polymer membrane stability. We found that the polymer membrane made of 4-arm PEG(40k)-Mal showed the highest stability on the cell surface. Also, the polymer membrane did not disturb the insulin secretion from beta cells.
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Affiliation(s)
- Shota Toda
- Department of Bioscience and Engineering, College of Systems Engineering and Science, Shibaura Institute of Technology, Saitama 337-8570, Japan; (S.T.); (N.N.)
| | - Artin Fattah
- Department of Immunology, Genetics and Pathology (IGP), Uppsala University, Dag Hammarskjölds väg 20, SE-751 85 Uppsala, Sweden; (A.F.); (K.N.E.); (B.N.)
| | - Kenta Asawa
- Department of Bioengineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan;
| | - Naoko Nakamura
- Department of Bioscience and Engineering, College of Systems Engineering and Science, Shibaura Institute of Technology, Saitama 337-8570, Japan; (S.T.); (N.N.)
| | - Kristina N. Ekdahl
- Department of Immunology, Genetics and Pathology (IGP), Uppsala University, Dag Hammarskjölds väg 20, SE-751 85 Uppsala, Sweden; (A.F.); (K.N.E.); (B.N.)
- Linnaeus Center of Biomaterials Chemistry, Linnaeus University, SE-391 82 Kalmar, Sweden
| | - Bo Nilsson
- Department of Immunology, Genetics and Pathology (IGP), Uppsala University, Dag Hammarskjölds väg 20, SE-751 85 Uppsala, Sweden; (A.F.); (K.N.E.); (B.N.)
| | - Yuji Teramura
- Department of Immunology, Genetics and Pathology (IGP), Uppsala University, Dag Hammarskjölds väg 20, SE-751 85 Uppsala, Sweden; (A.F.); (K.N.E.); (B.N.)
- Department of Bioengineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan;
- Correspondence: ; Tel.: +81-3-5841-1174
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19
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Paving the way for successful islet encapsulation. Drug Discov Today 2019; 24:737-748. [PMID: 30738185 DOI: 10.1016/j.drudis.2019.01.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 12/13/2018] [Accepted: 01/29/2019] [Indexed: 01/02/2023]
Abstract
Type 1 diabetes mellitus (T1DM) is a disorder that decimates pancreatic β-cells which produce insulin. Direct pancreatic islet transplantation cannot serve as a widespread therapeutic modality owing to the need for lifelong immunosuppression and donor shortage. Therefore, several encapsulation techniques have been developed to enclose the islets in semipermeable vehicles that will allow oxygen and nutrient input as well as insulin, other metabolites and waste output, while accomplishing immunoisolation. Although encapsulation technology continues to face significant obstacles, recent advances in material science, stem cell biology and immunology potentially serve as pathways to success. This review summarizes the accomplishments of the past 5 years.
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20
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Farina M, Alexander JF, Thekkedath U, Ferrari M, Grattoni A. Cell encapsulation: Overcoming barriers in cell transplantation in diabetes and beyond. Adv Drug Deliv Rev 2019; 139:92-115. [PMID: 29719210 DOI: 10.1016/j.addr.2018.04.018] [Citation(s) in RCA: 112] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/19/2018] [Accepted: 04/25/2018] [Indexed: 02/07/2023]
Abstract
Cell-based therapy is emerging as a promising strategy for treating a wide range of human diseases, such as diabetes, blood disorders, acute liver failure, spinal cord injury, and several types of cancer. Pancreatic islets, blood cells, hepatocytes, and stem cells are among the many cell types currently used for this strategy. The encapsulation of these "therapeutic" cells is under intense investigation to not only prevent immune rejection but also provide a controlled and supportive environment so they can function effectively. Some of the advanced encapsulation systems provide active agents to the cells and enable a complete retrieval of the graft in the case of an adverse body reaction. Here, we review various encapsulation strategies developed in academic and industrial settings, including the state-of-the-art technologies in advanced preclinical phases as well as those undergoing clinical trials, and assess their advantages and challenges. We also emphasize the importance of stimulus-responsive encapsulated cell systems that provide a "smart and live" therapeutic delivery to overcome barriers in cell transplantation as well as their use in patients.
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21
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Hartline CB, Conner RL, James SH, Potter J, Gray E, Estrada J, Tector M, Tector AJ, Prichard MN. Xenotransplantation panel for the detection of infectious agents in pigs. Xenotransplantation 2019; 25:e12427. [PMID: 30264882 PMCID: PMC6166664 DOI: 10.1111/xen.12427] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 05/18/2018] [Accepted: 05/25/2018] [Indexed: 01/04/2023]
Abstract
Background Recent advances in xenotransplantation have produced organs from pigs that are well tolerated in primate models because of genetic changes engineered to delete major antigens from donor animals. To ensure the safety of human transplant recipients, it will be essential to understand both the spectrum of infectious agents in donor pigs and their potential to be transmitted to immunocompromised transplant recipients. Equally important will be the development of new highly sensitive diagnostic methods for use in the detection of these agents in donor animals and for the monitoring of transplant recipients. Methods Herein, we report the development of a panel of 30 quantitative polymerase chain reaction (qPCR) assays for infectious agents with the potential to be transmitted to the human host. The reproducibility, sensitivity and specificity of each assay were evaluated and were found to exhibit analytic sensitivity that was similar to that of quantitative assays used to perform viral load testing of human viruses in clinical laboratories. Results This analytical approach was used to detect nucleic acids of infectious agents present in specimens from 9 sows and 22 piglets derived by caesarean section. The most commonly detected targets in adult animals were Mycoplasma species and two distinct herpesviruses, porcine lymphotrophic herpesvirus 2 and 3. A total of 14 piglets were derived from three sows infected with either or both herpesviruses, yet none tested positive for the viruses indicating that vertical transmission of these viruses is inefficient. Conclusions The data presented demonstrate that procedures in place are highly sensitive and can specifically detect nucleic acids from target organisms in the panel, thus ensuring the safety of organs for transplantation as well as the monitoring of patients potentially receiving them.
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Affiliation(s)
- Caroll B Hartline
- Department of Pediatrics, University of Alabama School of Medicine, Birmingham, AL, USA
| | - Ra'Shun L Conner
- Department of Pediatrics, University of Alabama School of Medicine, Birmingham, AL, USA
| | - Scott H James
- Department of Pediatrics, University of Alabama School of Medicine, Birmingham, AL, USA
| | - Jennifer Potter
- Department of Pediatrics, University of Alabama School of Medicine, Birmingham, AL, USA
| | - Edward Gray
- Department of Surgery, University of Alabama School of Medicine, Birmingham, AL, USA
| | - Jose Estrada
- Department of Surgery, University of Alabama School of Medicine, Birmingham, AL, USA
| | - Mathew Tector
- Department of Surgery, University of Alabama School of Medicine, Birmingham, AL, USA
| | - A Joseph Tector
- Department of Surgery, University of Alabama School of Medicine, Birmingham, AL, USA
| | - Mark N Prichard
- Department of Pediatrics, University of Alabama School of Medicine, Birmingham, AL, USA
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22
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Scobie L, Crossan C, Mourad NI, Galli C, Perota A, Gianello P. Viral pathogens: What are they and do they matter? Xenotransplantation 2018; 25:e12412. [PMID: 29913035 DOI: 10.1111/xen.12412] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 04/24/2018] [Accepted: 05/02/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Linda Scobie
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, UK
| | - Claire Crossan
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, UK
| | - Nizar I Mourad
- Laboratoire de Chirurgie Expérimentale et Transplantation, Université Catholique de Louvain, Brussels, Belgium
| | | | | | - Pierre Gianello
- Laboratoire de Chirurgie Expérimentale et Transplantation, Université Catholique de Louvain, Brussels, Belgium
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23
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Holdcraft RW, Dumpala PR, Smith BH, Gazda LS. A model for determining an effective in vivo dose of transplanted islets based on in vitro insulin secretion. Xenotransplantation 2018; 25:e12443. [PMID: 30054944 DOI: 10.1111/xen.12443] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 04/20/2018] [Accepted: 06/11/2018] [Indexed: 11/29/2022]
Abstract
BACKGROUND Allogeneic islet transplantation for the treatment of type 1 diabetes often requires multiple implant procedures, from as many as several human pancreas donors, to achieve lasting clinical benefit. Given the limited availability of human pancreases for islet isolation, porcine islets have long been considered a potential option for clinical use. Agarose-encapsulated porcine islets (macrobeads) permit long-term culture and thus a thorough evaluation of microbiological safety and daily insulin secretory capacity, prior to implantation. The goal of this study was the development of a method for determining an effective dose of encapsulated islets based on their measured in vitro insulin secretion in a preclinical model of type 1 diabetes. METHODS Spontaneously diabetic BioBreeding diabetes-prone rats were implanted with osmotic insulin pumps in combination with continuous glucose monitoring to establish the daily insulin dose required to achieve continuous euglycaemia in individual animals. Rats were then implanted with a 1×, 2× or 3× dose (defined as the ratio of macrobead in vitro insulin secretion per 24 hours to the recipient animal's total daily insulin requirement) of porcine islet macrobeads, in the absence of immunosuppression. In vivo macrobead function was assessed by recipient non-fasted morning blood glucose values, continuous glucose monitoring and the presence of peritoneal porcine C-peptide. At the end of the study, the implanted macrobeads were removed and returned to in vitro culture for the evaluation of insulin secretion. RESULTS Diabetic rats receiving a 2× macrobead implant exhibited significantly improved blood glucose regulation compared to that of rats receiving a 1× dose during a 30-day pilot study. In a 3-month follow-up study, 2× and 3× macrobead doses initially controlled blood glucose levels equally well, although several animals receiving a 3× dose maintained euglycaemia throughout the study, compared to none of the 2× animals. The presence of porcine C-peptide in rat peritoneal fluid 3 months post-implant and the recurrence of hyperglycaemia following macrobead removal, along with the finding of persistent in vitro insulin secretion from retrieved macrobeads, confirmed long-term graft function. CONCLUSIONS Increasing dosages of islet macrobeads transplanted into diabetic rats, based on multiples of in vitro insulin secretion matched to the recipient's exogenous insulin requirements, correlated with improved blood glucose regulation and increased duration of graft function. These results demonstrate the usefulness of a standardized model for the evaluation of the functional effectiveness of islets intended for transplantation, in this case using intraperitoneally implanted agarose macrobeads, in diabetic rats. The results suggest that some features of this islet-dosing methodology may be applicable, and indeed necessary, to clinical allogeneic and xenogeneic islet transplantation.
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Affiliation(s)
| | | | - Barry H Smith
- The Rogosin Institute, New York, New York.,NewYork Presbyterian - Weill Cornell Medical Center, New York, New York
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24
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Karuppannan AK, Opriessnig T. Possible risks posed by single-stranded DNA viruses of pigs associated with xenotransplantation. Xenotransplantation 2018; 25:e12453. [PMID: 30264878 PMCID: PMC6120555 DOI: 10.1111/xen.12453] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/12/2018] [Accepted: 07/20/2018] [Indexed: 12/11/2022]
Abstract
Routine large-scale xenotransplantation from pigs to humans is getting closer to clinical reality owing to several state-of-the-art technologies, especially the ability to rapidly engineer genetically defined pigs. However, using pig organs in humans poses risks including unwanted cross-species transfer of viruses and adaption of these pig viruses to the human organ recipient. Recent developments in the field of virology, including the advent of metagenomic techniques to characterize entire viromes, have led to the identification of a plethora of viruses in many niches. Single-stranded DNA (ssDNA) viruses are the largest group prevalent in virome studies in mammals. Specifically, the ssDNA viral genomes are characterized by a high rate of nucleotide substitution, which confers a proclivity to adapt to new hosts and cross-species barriers. Pig-associated ssDNA viruses include torque teno sus viruses (TTSuV) in the Anelloviridae family, porcine parvoviruses (PPV), and porcine bocaviruses (PBoV) both in the family of Parvoviridae, and porcine circoviruses (PCV) in the Circoviridae family, some of which have been confirmed to be pathogenic to pigs. The risks of these viruses for the human recipient during xenotransplantation procedures are relatively unknown. Based on the scant knowledge available on the prevalence, predilection, and pathogenicity of pig-associated ssDNA viruses, careful screening and monitoring are required. In the case of positive identification, risk assessments and strategies to eliminate these viruses in xenotransplantation pig stock may be needed.
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Affiliation(s)
- Anbu K. Karuppannan
- Department of Veterinary Diagnostic and Production Animal MedicineCollege of Veterinary MedicineIowa State UniversityAmesIowa
| | - Tanja Opriessnig
- Department of Veterinary Diagnostic and Production Animal MedicineCollege of Veterinary MedicineIowa State UniversityAmesIowa
- The Roslin Institute and The Royal (Dick) School of Veterinary StudiesUniversity of EdinburghRoslinMidlothianUK
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25
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Cowan PJ. The 2017 IXA Presidential Lecture: Recent developments in xenotransplantation. Xenotransplantation 2018; 25:e12416. [DOI: 10.1111/xen.12416] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 05/03/2018] [Indexed: 01/22/2023]
Affiliation(s)
- Peter J. Cowan
- Immunology Research Centre; St Vincent’s Hospital Melbourne; Department of Medicine; University of Melbourne; Melbourne Vic. Australia
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26
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The Origin, Dynamic Morphology, and PI4P-Independent Formation of Encephalomyocarditis Virus Replication Organelles. mBio 2018; 9:mBio.00420-18. [PMID: 29666283 PMCID: PMC5904412 DOI: 10.1128/mbio.00420-18] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Picornaviruses induce dramatic rearrangements of endomembranes in the cells that they infect to produce dedicated platforms for viral replication. These structures, termed replication organelles (ROs), have been well characterized for the Enterovirus genus of the Picornaviridae However, it is unknown whether the diverse RO morphologies associated with enterovirus infection are conserved among other picornaviruses. Here, we use serial electron tomography at different stages of infection to assess the three-dimensional architecture of ROs induced by encephalomyocarditis virus (EMCV), a member of the Cardiovirus genus of the family of picornaviruses that is distantly related. Ultrastructural analyses revealed connections between early single-membrane EMCV ROs and the endoplasmic reticulum (ER), establishing the ER as a likely donor organelle for their formation. These early single-membrane ROs appear to transform into double-membrane vesicles (DMVs) as infection progresses. Both single- and double-membrane structures were found to support viral RNA synthesis, and progeny viruses accumulated in close proximity, suggesting a spatial association between RNA synthesis and virus assembly. Further, we explored the role of phosphatidylinositol 4-phosphate (PI4P), a critical host factor for both enterovirus and cardiovirus replication that has been recently found to expedite enterovirus RO formation rather than being strictly required. By exploiting an EMCV escape mutant, we found that low-PI4P conditions could also be overcome for the formation of cardiovirus ROs. Collectively, our data show that despite differences in the membrane source, there are striking similarities in the biogenesis, morphology, and transformation of cardiovirus and enterovirus ROs, which may well extend to other picornaviruses.IMPORTANCE Like all positive-sense RNA viruses, picornaviruses induce the rearrangement of host cell membranes to form unique structures, or replication organelles (ROs), that support viral RNA synthesis. Here, we investigate the architecture and biogenesis of cardiovirus ROs and compare them with those induced by enteroviruses, members of the well-characterized picornavirus genus Enterovirus The origins and dynamic morphologies of cardiovirus ROs are revealed using electron tomography, which points to the endoplasmic reticulum as the donor organelle usurped to produce single-membrane tubules and vesicles that transform into double-membrane vesicles. We show that PI4P, a critical lipid for cardiovirus and enterovirus replication, is not strictly required for the formation of cardiovirus ROs, as functional ROs with typical morphologies are formed under phosphatidylinositol 4-kinase type III alpha (PI4KA) inhibition in cells infected with an escape mutant. Our data show that the transformation from single-membrane structures to double-membrane vesicles is a conserved feature of cardiovirus and enterovirus infections that likely extends to other picornavirus genera.
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27
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Denner J. Why was PERV not transmitted during preclinical and clinical xenotransplantation trials and after inoculation of animals? Retrovirology 2018; 15:28. [PMID: 29609635 PMCID: PMC5879552 DOI: 10.1186/s12977-018-0411-8] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 03/22/2018] [Indexed: 01/27/2023] Open
Abstract
Porcine endogenous retroviruses (PERVs) are present in the genome of all pigs, they infect certain human cells and therefore pose a special risk for xenotransplantation using pig cells, tissues and organs. Xenotransplantation is being developed in order to alleviate the reduced availability of human organs. Despite the fact that PERVs are able to infect certain human cells and cells from other species, transmission of PERVs has not been observed when animals (including non-human primates) were inoculated with PERV preparations or during preclinical xenotransplantations. The data indicate that PERVs were not transmitted because they were not released from the transplant or were inhibited by intracellular restriction factors and innate immunity in the recipient. In a single study in guinea pigs, a transient PERV infection and anti-PERV antibodies were described, indicating that in this case at least, the immune system may also have been involved.
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Affiliation(s)
- Joachim Denner
- Robert Koch Institute, Nordufer 20, 13353, Berlin, Germany.
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28
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Abstract
PURPOSE OF REVIEW To review the progress in the field of xenotransplantation with special attention to most recent encouraging findings which will eventually bring xenotransplantation to the clinic in the near future. RECENT FINDINGS Starting from early 2000, with the introduction of galactose-α1,3-galactose (Gal)-knockout pigs, prolonged survival especially in heart and kidney xenotransplantation was recorded. However, remaining antibody barriers to non-Gal antigens continue to be the hurdle to overcome. The production of genetically engineered pigs was difficult requiring prolonged time. However, advances in gene editing, such as zinc finger nucleases, transcription activator-like effector nucleases, and most recently clustered regularly interspaced short palindromic repeats (CRISPR) technology made the production of genetically engineered pigs easier and available to more researchers. Today, the survival of pig-to-nonhuman primate heterotopic heart, kidney, and islet xenotransplantation reached more than 900, more than 400, and more than 600 days, respectively. The availability of multiple-gene pigs (five or six genetic modifications) and/or newer costimulation blockade agents significantly contributed to this success. Now, the field is getting ready for clinical trials with an international consensus. SUMMARY Clinical trials in cellular or solid organ xenotransplantation are getting closer with convincing preclinical data from many centers. The next decade will show us new achievements and additional barriers in clinical xenotransplantation.
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29
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Zarrintaj P, Manouchehri S, Ahmadi Z, Saeb MR, Urbanska AM, Kaplan DL, Mozafari M. Agarose-based biomaterials for tissue engineering. Carbohydr Polym 2018; 187:66-84. [PMID: 29486846 DOI: 10.1016/j.carbpol.2018.01.060] [Citation(s) in RCA: 305] [Impact Index Per Article: 50.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 12/28/2017] [Accepted: 01/18/2018] [Indexed: 01/08/2023]
Abstract
Agarose is a natural polysaccharide polymer having unique characteristics that give reason to consider it for tissue engineering applications. Special characteristics of agarose such as its excellent biocompatibility, thermo-reversible gelation behavior and physiochemical features support its use as a biomaterial for cell growth and/or controlled/localized drug delivery. The resemblance of this natural carbohydrate polymer to the extracellular matrix results in attractive features that bring about a strong interest in its usage in the field. The scope of this review is to summarize the extensive researches addressing agarose-based biomaterials in order to provide an in-depth understanding of its tissue engineering-related applications.
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Affiliation(s)
- Payam Zarrintaj
- School of Chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Saeed Manouchehri
- School of Chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Zahed Ahmadi
- Department of Chemistry, Amirkabir University of Technology, Tehran, Iran
| | - Mohammad Reza Saeb
- Department of Resin and Additives, Institute for Color Science and Technology, P.O. Box: 16765-654, Tehran, Iran.
| | | | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA
| | - Masoud Mozafari
- Bioengineering Research Group, Nanotechnology and Advanced Materials Department, Materials and Energy Research Center (MERC), Tehran, Iran; Cellular and Molecular Research Center, Iran University of Medical Sciences (IUMS), Tehran, Iran; Department of Tissue Engineering & Regenerative Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences (IUMS), Tehran, Iran.
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30
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Stehlik J, Kobashigawa J, Hunt SA, Reichenspurner H, Kirklin JK. Honoring 50 Years of Clinical Heart Transplantation in
Circulation. Circulation 2018; 137:71-87. [DOI: 10.1161/circulationaha.117.029753] [Citation(s) in RCA: 104] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Heart transplantation has become a standard therapy option for advanced heart failure. The translation of heart transplantation from innovative experiments to long-term clinical success has married prescient insights with discipline and organization in the domains of surgical techniques, organ preservation, immunosuppression, organ donation and transplantation logistics, infection control, and long-term graft surveillance. This review explores the key milestones of the past 50 years of heart transplantation and discusses current challenges and promising innovations on the clinical horizon.
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Affiliation(s)
- Josef Stehlik
- Division of Cardiovascular Medicine, University of Utah School of Medicine, Salt Lake City (J.S.)
| | | | - Sharon A. Hunt
- Division of Cardiovascular Medicine, Stanford University, CA (S.A.H.)
| | | | - James K. Kirklin
- Division of Cardiothoracic Surgery, University of Alabama at Birmingham (J.K.K.)
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31
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Cooper DKC, Cowan P, Fishman JA, Hering BJ, Mohiuddin MM, Pierson RN, Sachs DH, Schuurman HJ, Dennis JU, Tönjes RR. Joint FDA‐IXA Symposium, September 20, 2017. Xenotransplantation 2017; 24. [PMID: 29193342 DOI: 10.1111/xen.12365] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- David K C Cooper
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Peter Cowan
- Immunology Research Centre, St Vincent's Hospital, Melbourne, Victoria, Australia
| | - Jay A Fishman
- Infectious Disease Division and MGH Transplant Center, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Bernhard J Hering
- Department of Surgery, University of Minnesota, Minneapolis, MN, USA
| | - Muhammad M Mohiuddin
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Richard N Pierson
- Department of Surgery, University of Maryland School of Medicine, Baltimore VA Medical Center, Baltimore, MD, USA
| | - David H Sachs
- Columbia University Medical Center, New York City, NY, USA.,Harvard Medical School and Massachusetts General Hospital, Boston, MA, USA
| | | | - John U Dennis
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Ralf R Tönjes
- Paul-Ehrlich-Institut, Federal Institute for Vaccines and Biomedicines, Division of Medical Biotechnology, Langen, Germany
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Güell M, Niu D, Kan Y, George H, Wang T, Lee IH, Wang G, Church G, Yang L. PERV inactivation is necessary to guarantee absence of pig-to-patient PERVs transmission in xenotransplantation. Xenotransplantation 2017; 24. [PMID: 29171094 DOI: 10.1111/xen.12366] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 10/30/2017] [Indexed: 01/27/2023]
Affiliation(s)
| | - Dong Niu
- eGenesis Inc., Boston, MA, USA.,College of Animal Sciences, Zhejiang University, Hangzhou, China
| | | | | | | | | | | | - George Church
- Department of Genetics, Harvard Medical School, Boston, MA, USA
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Cowan PJ, Tector AJ. The Resurgence of Xenotransplantation. Am J Transplant 2017; 17:2531-2536. [PMID: 28397351 DOI: 10.1111/ajt.14311] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 03/21/2017] [Accepted: 04/01/2017] [Indexed: 01/25/2023]
Abstract
There has been an upsurge of interest in xenotransplantation in recent years. This resurgence can attributed to a combination of factors. First, there has been a dramatic improvement in efficacy in several preclinical models, with maximum xenograft survival times increasing to 950 days for islets, 945 days for hearts, and 310 days for kidneys. Second, the rapid development of genome editing technology (particularly the advent of clustered regularly interspaced short palindromic repeats/Cas9) has revolutionized the capacity to generate new donor pigs with multiple protective genetic modifications; what once took many years to achieve can now be performed in months, with much greater precision and scope. Third, the specter of porcine endogenous retrovirus (PERV) has receded significantly. There has been no evidence of PERV transmission in clinical trials and preclinical models, and improved screening methods and new options for the treatment or even elimination of PERV are now available. Balancing these positive developments are several remaining challenges, notably the heavy and often clinically inapplicable immunosuppression required to prevent xenograft rejection. Nonetheless, the potential for xenotransplantation as a solution to the shortage of human organs and tissues for transplantation continues to grow.
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Affiliation(s)
- P J Cowan
- Immunology Research Centre, St Vincent's Hospital Melbourne, Victoria, Australia.,Department of Medicine, University of Melbourne, Victoria, Australia
| | - A J Tector
- School of Medicine, University of Alabama, Birmingham, AL
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Mourad NI, Crossan C, Cruikshank V, Scobie L, Gianello P. Characterization of porcine endogenous retrovirus expression in neonatal and adult pig pancreatic islets. Xenotransplantation 2017; 24. [DOI: 10.1111/xen.12311] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 03/29/2017] [Accepted: 04/01/2017] [Indexed: 01/14/2023]
Affiliation(s)
- Nizar I. Mourad
- Pôle de chirurgie expérimentale et transplantation; Université catholique de Louvain; Brussels Belgium
| | - Claire Crossan
- School of Health and Life Sciences; Glasgow Caledonian University; Glasgow Scotland
| | - Victoria Cruikshank
- School of Health and Life Sciences; Glasgow Caledonian University; Glasgow Scotland
| | - Linda Scobie
- School of Health and Life Sciences; Glasgow Caledonian University; Glasgow Scotland
| | - Pierre Gianello
- Pôle de chirurgie expérimentale et transplantation; Université catholique de Louvain; Brussels Belgium
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Denner J. Sensitive methods and improved screening strategies are needed for the detection of pig viruses. Xenotransplantation 2017; 24. [PMID: 28432699 DOI: 10.1111/xen.12303] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 03/03/2017] [Accepted: 03/09/2017] [Indexed: 01/23/2023]
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Denner J, Mankertz A. Porcine Circoviruses and Xenotransplantation. Viruses 2017; 9:v9040083. [PMID: 28425928 PMCID: PMC5408689 DOI: 10.3390/v9040083] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 04/06/2017] [Accepted: 04/12/2017] [Indexed: 02/07/2023] Open
Abstract
Allotransplantation and xenotransplantation may be associated with the transmission of pathogens from the donor to the recipient. Whereas in the case of allotransplantation the transmitted microorganisms and their pathogenic effect are well characterized, the possible influence of porcine microorganisms on humans is mostly unknown. Porcine circoviruses (PCVs) are common in pig breeds and they belong to porcine microorganisms that still have not been fully addressed in terms of evaluating the potential risk of xenotransplantation using pig cells, tissues, and organs. Two types of PCVs are known: porcine circovirus (PCV) 1 and PCV2. Whereas PCV1 is apathogenic in pigs, PCV2 may induce severe pig diseases. Although most pigs are subclinically infected, we do not know whether this infection impairs pig transplant functionality, particularly because PCV2 is immunosuppressive. In addition, vaccination against PCV2 is able to prevent diseases, but in most cases not transmission of the virus. Therefore, PCV2 has to be eliminated to obtain xenotransplants from uninfected healthy animals. Although there is evidence that PCV2 does not infect—at least immunocompetent—humans, animals should be screened using sensitive methods to ensure virus elimination by selection, Cesarean delivery, vaccination, or embryo transfer.
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Affiliation(s)
- Joachim Denner
- Robert Koch Institute, Nordufer 20, 13353 Berlin, Germany.
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Steinhoff M, Naqvi R, Burlak C. Xenotransplantation literature update, November/December 2016. Xenotransplantation 2017; 24. [PMID: 28160329 DOI: 10.1111/xen.12290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2017] [Accepted: 01/18/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Magie Steinhoff
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota School of Medicine, Minneapolis, MN, USA
| | - Raza Naqvi
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota School of Medicine, Minneapolis, MN, USA
| | - Christopher Burlak
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota School of Medicine, Minneapolis, MN, USA
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Schuurman HJ. Microbiological safety of clinical xenotransplantation products: monitoring strategies and regulatory aspects. A commentary. Xenotransplantation 2016; 23:440-443. [PMID: 27859642 DOI: 10.1111/xen.12280] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 10/07/2016] [Indexed: 01/17/2023]
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Gazda LS, Collins J, Lovatt A, Holdcraft RW, Morin MJ, Galbraith D, Graham M, Laramore MA, Maclean C, Black J, Milne EW, Marthaler DG, Vinerean HV, Michalak MM, Hoffer D, Richter S, Hall RD, Smith BH. A comprehensive microbiological safety approach for agarose encapsulated porcine islets intended for clinical trials. Xenotransplantation 2016; 23:444-463. [PMID: 27862363 PMCID: PMC7169751 DOI: 10.1111/xen.12277] [Citation(s) in RCA: 38] [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: 03/08/2016] [Revised: 09/06/2016] [Accepted: 09/22/2016] [Indexed: 12/15/2022]
Abstract
BACKGROUND The use of porcine islets to replace insulin-producing islet β-cells, destroyed during the diabetogenic disease process, presents distinct challenges if this option is to become a therapeutic reality for the treatment of type 1 diabetes. These challenges include a thorough evaluation of the microbiological safety of the islets. In this study, we describe a robust porcine islet-screening program that provides a high level of confidence in the microbiological safety of porcine islets suitable for clinical trials. METHODS A four-checkpoint program systematically screens the donor herd (Large White - Yorkshire × Landrace F1 hybrid animals), individual sentinel and pancreas donor animals and, critically, the islet macrobeads themselves. Molecular assays screen for more than 30 known viruses, while electron microscopy and in vitro studies are employed to screen for potential new or divergent (emergent) viruses. RESULTS Of 1207 monthly samples taken from random animals over a 2-year period, only a single positive result for Transmissible gastroenteritis virus was observed, demonstrating the high level of biosecurity maintained in the source herd. Given the lack of clinical signs, positive antibody titers for Porcine reproductive and respiratory syndrome virus, Porcine parvovirus, and Influenza A confirm the efficacy of the herd vaccination program. Porcine respiratory coronavirus was found to be present in the herd, as expected for domestic swine. Tissue homogenate samples from six sentinel and 11 donor animals, over the same 2-year period, were negative for the presence of viruses when co-cultured with six different cell lines from four species. The absence of adventitious viruses in separate islet macrobead preparations produced from 12 individual pancreas donor animals was confirmed using validated molecular (n = 32 viruses), in vitro culture (cells from four species), and transmission electron microscopy assays (200 cell profiles per donor animal) over the same 2-year period. There has been no evidence of viral transmission following the implantation of these same encapsulated and functional porcine islets into non-immunosuppressed diabetic cynomolgus macaques for up to 4 years. Isolated peripheral blood mononuclear cells from all time points were negative for PCV (Type 2), PLHV, PRRSV, PCMV, and PERV-A, PERV-B, and PERV-C by PCR analysis in all six recipient animals. CONCLUSION The four-checkpoint program is a robust and reliable method for characterization of the microbiological safety of encapsulated porcine islets intended for clinical trials.
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Affiliation(s)
| | - James Collins
- Veterinary Diagnostic LaboratoryUniversity of MinnesotaSaint PaulMNUSA
| | | | | | | | | | - Melanie Graham
- Department of SurgeryUniversity of MinnesotaSaint PaulMNUSA
- Department of Veterinary Population MedicineUniversity of MinnesotaSaint PaulMNUSA
| | | | | | | | | | - Douglas G. Marthaler
- Veterinary Diagnostic LaboratoryUniversity of MinnesotaSaint PaulMNUSA
- Department of Veterinary Population MedicineUniversity of MinnesotaSaint PaulMNUSA
| | - Horatiu V. Vinerean
- Office of Laboratory Animal ResearchFlorida International UniversityMiamiFLUSA
- Department of SurgeryHerbert Wertheim College of MedicineMiamiFLUSA
| | | | | | | | | | - Barry H. Smith
- Department of SurgeryWeill Medical College of Cornell University and NewYork‐Presbyterian HospitalNew YorkNYUSA
- The Rogosin InstituteNew YorkNYUSA
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Retention of gene expression in porcine islets after agarose encapsulation and long-term culture. Biochem Biophys Res Commun 2016; 476:580-585. [DOI: 10.1016/j.bbrc.2016.05.165] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 05/30/2016] [Indexed: 12/21/2022]
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