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Liu Y, Niu Y, Ma X, Xiang Y, Wu D, Li W, Wang T, Niu D. Porcine endogenous retrovirus: classification, molecular structure, regulation, function, and potential risk in xenotransplantation. Funct Integr Genomics 2023; 23:60. [PMID: 36790562 DOI: 10.1007/s10142-023-00984-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 02/04/2023] [Accepted: 02/06/2023] [Indexed: 02/16/2023]
Abstract
Xenotransplantation with porcine organs has been recognized as a promising solution to alleviate the shortage of organs for human transplantation. Porcine endogenous retrovirus (PERV), whose proviral DNAs are integrated in the genome of all pig breeds, is a main microbiological risk for xenotransplantation. Over the last decades, some advances on PERVs' studies have been achieved. Here, we reviewed the current progress of PERVs including the classification, molecular structure, regulation, function in immune system, and potential risk in xenotransplantation. We also discussed the problem of insufficient study on PERVs as well as the questions need to be answered in the future work.
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Affiliation(s)
- Yu Liu
- College of Animal Science and Technology & College of Veterinary Medicine, Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, Provincial Engineering Research Center for Animal Health Diagnostics & Advanced Technology, Zhejiang International Science and Technology Cooperation Base for Veterinary Medicine and Health Management, China Australia Joint Laboratory for Animal Health Big Data Analytics, Zhejiang A&F University, Hangzhou, Zhejiang, 311300, China
| | - Yifan Niu
- College of Animal Science and Technology & College of Veterinary Medicine, Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, Provincial Engineering Research Center for Animal Health Diagnostics & Advanced Technology, Zhejiang International Science and Technology Cooperation Base for Veterinary Medicine and Health Management, China Australia Joint Laboratory for Animal Health Big Data Analytics, Zhejiang A&F University, Hangzhou, Zhejiang, 311300, China
| | - Xiang Ma
- College of Animal Science and Technology & College of Veterinary Medicine, Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, Provincial Engineering Research Center for Animal Health Diagnostics & Advanced Technology, Zhejiang International Science and Technology Cooperation Base for Veterinary Medicine and Health Management, China Australia Joint Laboratory for Animal Health Big Data Analytics, Zhejiang A&F University, Hangzhou, Zhejiang, 311300, China.,College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, 310058, China.,Jinhua Jinfan Feed Co., Ltd, Jinhua, Zhejiang, 321000, China
| | - Yun Xiang
- Jinhua Academy of Agricultural Sciences, Jinhua, Zhejiang, 321000, China
| | - De Wu
- Postdoctoral Research Station, Jinhua Development Zone, Jinhua, Zhejiang, 321000, China
| | - Weifen Li
- College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
| | - Tao Wang
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, Jiangsu, 211300, China.
| | - Dong Niu
- College of Animal Science and Technology & College of Veterinary Medicine, Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, Provincial Engineering Research Center for Animal Health Diagnostics & Advanced Technology, Zhejiang International Science and Technology Cooperation Base for Veterinary Medicine and Health Management, China Australia Joint Laboratory for Animal Health Big Data Analytics, Zhejiang A&F University, Hangzhou, Zhejiang, 311300, China.
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Identification of DNA methylation regulated novel host genes relevant to inhibition of virus replication in porcine PK15 cell using double stranded RNA mimics and DNA methyltransferase inhibitor. Genomics 2018; 111:1464-1473. [PMID: 30315899 PMCID: PMC7125705 DOI: 10.1016/j.ygeno.2018.09.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 09/27/2018] [Accepted: 09/28/2018] [Indexed: 12/24/2022]
Abstract
During RNA viruses's replication, double-stranded RNA (dsRNA) is normally produced and induce host innate immune response. Most of gene activation due cytokine mediated but which are due to methylation mediated is still unknown. In the study, DNA methylome was integrated with our previous transcriptome data to investigate the differentially methylated regions and genes using MeDIP-chip technology. We found that the transcriptional expressions of 15, 37 and 18 genes were negatively related with their promoter DNA methylation levels in the cells treated by PolyI:C, Aza-CdR, as well as PolyI:C plus Aza-CdR, respectively, compared with the untreated cells. GO analysis revealed hypo-methylated genes (BNIP3L and CDK9) and a hyper-methylated gene (ZC3HAV1) involved in the host response to viral replication. Our results suggest that these novel genes targeted by DNA methylation can be potential markers relevant to virus replication and host innate immune response to set up a medical model of infectious diseases.
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3
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Łopata K, Wojdas E, Nowak R, Łopata P, Mazurek U. Porcine Endogenous Retrovirus (PERV) - Molecular Structure and Replication Strategy in the Context of Retroviral Infection Risk of Human Cells. Front Microbiol 2018; 9:730. [PMID: 29755422 PMCID: PMC5932395 DOI: 10.3389/fmicb.2018.00730] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Accepted: 03/28/2018] [Indexed: 12/28/2022] Open
Abstract
The xenotransplantation of porcine tissues may help overcome the shortage of human organs for transplantation. However, there are some concerns about recipient safety because the risk of porcine endogenous retrovirus (PERV) transmission to human cells remains unknown. Although, to date, no PERV infections have been noted in vivo, the possibility of such infections has been confirmed in vitro. Better understanding of the structure and replication cycle of PERVs is a prerequisite for determining the risk of infection and planning PERV-detection strategies. This review presents the current state of knowledge about the structure and replication cycle of PERVs in the context of retroviral infection risk.
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Affiliation(s)
- Krzysztof Łopata
- Department of Molecular Biology, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Emilia Wojdas
- Department of Molecular Biology, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland.,Department of Instrumental Analysis, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Roman Nowak
- Department of Molecular Biology, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Paweł Łopata
- Department of Molecular Biology, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Urszula Mazurek
- Department of Molecular Biology, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland
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Greenwood AD, Ishida Y, O'Brien SP, Roca AL, Eiden MV. Transmission, Evolution, and Endogenization: Lessons Learned from Recent Retroviral Invasions. Microbiol Mol Biol Rev 2018; 82:e00044-17. [PMID: 29237726 PMCID: PMC5813887 DOI: 10.1128/mmbr.00044-17] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Viruses of the subfamily Orthoretrovirinae are defined by the ability to reverse transcribe an RNA genome into DNA that integrates into the host cell genome during the intracellular virus life cycle. Exogenous retroviruses (XRVs) are horizontally transmitted between host individuals, with disease outcome depending on interactions between the retrovirus and the host organism. When retroviruses infect germ line cells of the host, they may become endogenous retroviruses (ERVs), which are permanent elements in the host germ line that are subject to vertical transmission. These ERVs sometimes remain infectious and can themselves give rise to XRVs. This review integrates recent developments in the phylogenetic classification of retroviruses and the identification of retroviral receptors to elucidate the origins and evolution of XRVs and ERVs. We consider whether ERVs may recurrently pressure XRVs to shift receptor usage to sidestep ERV interference. We discuss how related retroviruses undergo alternative fates in different host lineages after endogenization, with koala retrovirus (KoRV) receiving notable interest as a recent invader of its host germ line. KoRV is heritable but also infectious, which provides insights into the early stages of germ line invasions as well as XRV generation from ERVs. The relationship of KoRV to primate and other retroviruses is placed in the context of host biogeography and the potential role of bats and rodents as vectors for interspecies viral transmission. Combining studies of extant XRVs and "fossil" endogenous retroviruses in koalas and other Australasian species has broadened our understanding of the evolution of retroviruses and host-retrovirus interactions.
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Affiliation(s)
- Alex D Greenwood
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research (IZW) in the Forschungsverbund Berlin e.V., Berlin, Germany
| | - Yasuko Ishida
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Sean P O'Brien
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Alfred L Roca
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Maribeth V Eiden
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research (IZW) in the Forschungsverbund Berlin e.V., Berlin, Germany
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Deng J, Qu X, Lu P, Yang X, Zhu Y, Ji H, Wang Y, Jiang Z, Li X, Zhong Y, Yang H, Pan H, Young WB, Zhu H. Specific and Stable Suppression of HIV Provirus Expression In Vitro by Chimeric Zinc Finger DNA Methyltransferase 1. MOLECULAR THERAPY. NUCLEIC ACIDS 2017; 6:233-242. [PMID: 28325289 PMCID: PMC5363508 DOI: 10.1016/j.omtn.2017.01.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 12/20/2016] [Accepted: 01/09/2017] [Indexed: 12/25/2022]
Abstract
HIV-1 inserts its proviral DNA into the infected host cells, by which HIV proviral DNA can then be duplicated along with each cell division. Thus, provirus cannot be eradicated completely by current antiretroviral therapy. We have developed an innovative strategy to silence the HIV provirus by targeted DNA methylation on the HIV promoter region. We genetically engineered a chimeric DNA methyltransferase 1 composed of designed zinc-finger proteins to become ZF2 DNMT1. After transient transfection of the molecular clone encoding this chimeric protein into HIV-1 infected or latently infected cells, efficient suppression of HIV-1 expression by the methylation of CpG islands in 5′-LTR was observed and quantified. The effective suppression of HIV in latently infected cells by ZF2-DNMT1 is stable and can last through about 40 cell passages. Cytotoxic caused by ZF2-DNMT1 was only observed during cellular proliferation. Taken together, our results demonstrate the potential of this novel approach for anti-HIV-1 therapy.
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Affiliation(s)
- Junxiao Deng
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xiying Qu
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Panpan Lu
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xinyi Yang
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Yuqi Zhu
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Haiyan Ji
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Yanan Wang
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Zhengtao Jiang
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xian Li
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Yangcheng Zhong
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - He Yang
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Hanyu Pan
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Won-Bin Young
- Department of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15219, USA
| | - Huanzhang Zhu
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200438, China.
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Spizzo T, Denner J, Gazda L, Martin M, Nathu D, Scobie L, Takeuchi Y. First update of the International Xenotransplantation Association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes-Chapter 2a: source pigs-preventing xenozoonoses. Xenotransplantation 2016; 23:25-31. [DOI: 10.1111/xen.12223] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 02/08/2016] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | | | | | - Linda Scobie
- School of Health and Life Sciences; Glasgow Caledonian University; Glasgow Scotland
| | - Yasuhiro Takeuchi
- Division of Infection and Immunity; Wohl Virion Centre; University College London; London UK
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Weber S, Jung S, Doerfler W. DNA methylation and transcription in HERV (K, W, E) and LINE sequences remain unchanged upon foreign DNA insertions. Epigenomics 2016; 8:157-65. [DOI: 10.2217/epi.15.109] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Aim: DNA methylation and transcriptional profiles were determined in the regulatory sequences of the human endogenous retroviral (HERV-K, -W, -E) and LINE-1.2 elements and were compared between non-transgenomic and plasmid-transgenomic cells. Methods: DNA methylation profiles in the HERV (K, W, E) and LINE sequences were determined by bisulfite genomic sequencing. The transcription of these genome segments was assessed by quantitative real-time PCR. Results: In HERV-K, HERV-W and LINE-1.2 the levels of DNA methylation ranged between 75 and 98%, while in HERV-E they were around 60%. Nevertheless, the HERV and LINE-1.2 sequences were actively transcribed. No differences were found in comparisons of HERV and LINE-1.2 CpG methylation and transcription patterns between non-transgenomic and plasmid-transgenomic HCT116 cells. Conclusion: The insertion of a 5.6 kbp plasmid into the HCT116 genome had no effect on the HERV and LINE-1.2 methylation and transcription profiles, although other parts of the HCT116 genome had shown marked changes. These repetitive sequences are transcribed, probably because the large number of HERV and LINE-1.2 elements harbor copies with non- or hypo-methylated long terminal repeat sequences.
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Affiliation(s)
- Stefanie Weber
- Institute of Clinical & Molecular Virology, University Erlangen-Nürnberg Medical School, 91054 Erlangen, Germany
| | - Susan Jung
- Pediatric Research Center, University Erlangen-Nürnberg, 91052 Erlangen, Germany
| | - Walter Doerfler
- Institute of Clinical & Molecular Virology, University Erlangen-Nürnberg Medical School, 91054 Erlangen, Germany
- Institute of Genetics, University of Cologne, 50674 Cologne, Germany
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Garcia-Etxebarria K, Sistiaga-Poveda M, Jugo BM. Endogenous retroviruses in domestic animals. Curr Genomics 2014; 15:256-65. [PMID: 25132796 PMCID: PMC4133949 DOI: 10.2174/1389202915666140520003503] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 05/14/2014] [Accepted: 05/16/2014] [Indexed: 01/15/2023] Open
Abstract
Endogenous retroviruses (ERVs) are genomic elements that are present in a wide range of vertebrates. Although the study of ERVs has been carried out mainly in humans and model organisms, recently, domestic animals have become important, and some species have begun to be analyzed to gain further insight into ERVs. Due to the availability of complete genomes and the development of new computer tools, ERVs can now be analyzed from a genome-wide viewpoint. In addition, more experimental work is being carried out to analyze the distribution, expression and interplay of ERVs within a host genome. Cats, cattle, chicken, dogs, horses, pigs and sheep have been scrutinized in this manner, all of which are interesting species in health and economic terms. Furthermore, several studies have noted differences in the number of endogenous retroviruses and in the variability of these elements among different breeds, as well as their expression in different tissues and the effects of their locations, which, in some cases, are near genes. These findings suggest a complex, intriguing relationship between ERVs and host genomes. In this review, we summarize the most important in silico and experimental findings, discuss their implications and attempt to predict future directions for the study of these genomic elements.
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Affiliation(s)
- Koldo Garcia-Etxebarria
- Genetika, Antropologia Fisikoa eta Animalien Fisiologia Saila. Zientzia eta Teknologia Fakultatea. Euskal Herriko Unibertsitatea (UPV/EHU). 644 Postakutxa , E-48080 Bilbao, Spain
| | - Maialen Sistiaga-Poveda
- Genetika, Antropologia Fisikoa eta Animalien Fisiologia Saila. Zientzia eta Teknologia Fakultatea. Euskal Herriko Unibertsitatea (UPV/EHU). 644 Postakutxa , E-48080 Bilbao, Spain
| | - Begoña Marina Jugo
- Genetika, Antropologia Fisikoa eta Animalien Fisiologia Saila. Zientzia eta Teknologia Fakultatea. Euskal Herriko Unibertsitatea (UPV/EHU). 644 Postakutxa , E-48080 Bilbao, Spain
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Porcine endogenous retroviruses in xenotransplantation--molecular aspects. Viruses 2014; 6:2062-83. [PMID: 24828841 PMCID: PMC4036542 DOI: 10.3390/v6052062] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 04/15/2014] [Accepted: 04/26/2014] [Indexed: 02/06/2023] Open
Abstract
In the context of the shortage of organs and other tissues for use in human transplantation, xenotransplantation procedures with material taken from pigs have come under increased consideration. However, there are unclear consequences of the potential transmission of porcine pathogens to humans. Of particular concern are porcine endogenous retroviruses (PERVs). Three subtypes of PERV have been identified, of which PERV-A and PERV-B have the ability to infect human cells in vitro. The PERV-C subtype does not show this ability but recombinant PERV-A/C forms have demonstrated infectivity in human cells. In view of the risk presented by these observations, the International Xenotransplantation Association recently indicated the existence of four strategies to prevent transmission of PERVs. This article focuses on the molecular aspects of PERV infection in xenotransplantation and reviews the techniques available for the detection of PERV DNA, RNA, reverse transcriptase activity and proteins, and anti-PERV antibodies to enable carrying out these recommendations. These methods could be used to evaluate the risk of PERV transmission in human recipients, enhance the effectiveness and reliability of monitoring procedures, and stimulate discussion on the development of improved, more sensitive methods for the detection of PERVs in the future.
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Gola J, Mazurek U. Detection of porcine endogenous retrovirus in xenotransplantation. Reprod Biol 2014; 14:68-73. [PMID: 24607257 DOI: 10.1016/j.repbio.2014.01.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 01/22/2014] [Accepted: 01/23/2014] [Indexed: 10/25/2022]
Abstract
Xenotransplantation can provide a virtually limitless supply of cells, tissues and organs for a variety of therapeutic procedures. Cells and tissues for use in human transplantation procedures could be supplied using material taken from pigs. However, there is a potential risk of transmission of porcine infectious agents, including porcine endogenous retroviruses (PERVs), to a novel human host, with as yet unknown consequences. Three subtypes of PERV have been identified, of which both PERV-A and PERV-B have the ability to infect human cells in vitro. The third subtype, PERV-C, does not show this ability. Recombinant PERV-A/C forms have demonstrated infectivity in human cell culture. Monitoring in xenotransplantation should comprise screening of the source pig herd (PERV-A and PERV-B level expression assessment, PERV-C detection) and screening of recipients (differentiation between PERV transmission and chimerism). The detection of PERVs includes analyses of both DNA and RNA (PCR and RT-PCR), quantitative determination of the level of PERV nucleic acids (real-time PCR and real-time RT-PCR), assessment of reverse transcriptase (RT) activity (RT assays) and viral and recipient protein detection (immunological methods). In summary, all available methods should be used in monitoring of PERVs in xenotransplantation, and caution should be exercised at all stages of monitoring. Such monitoring has enormous significance for eliminating the possibility of transmission of PERV infection, thus contributing to higher levels of safety in xenotransplantation.
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Affiliation(s)
- Joanna Gola
- Department of Molecular Biology, Medical University of Silesia, Jednosci 8, 41-200 Sosnowiec, Poland.
| | - Urszula Mazurek
- Department of Molecular Biology, Medical University of Silesia, Jednosci 8, 41-200 Sosnowiec, Poland.
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Schneider MKJ, Seebach JD. Xenotransplantation literature update, November-December 2013. Xenotransplantation 2014; 21:91-5. [PMID: 24444051 DOI: 10.1111/xen.12084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 12/23/2013] [Indexed: 11/29/2022]
Affiliation(s)
- Mårten K J Schneider
- Laboratory of Vascular Immunology, Division of Internal Medicine, University Hospital Zurich, Switzerland
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