1
|
Stockdale SR, Blanchard AM, Nayak A, Husain A, Nashine R, Dudani H, McClure CP, Tarr AW, Nag A, Meena E, Sinha V, Shrivastava SK, Hill C, Singer AC, Gomes RL, Acheampong E, Chidambaram SB, Bhatnagar T, Vetrivel U, Arora S, Kashyap RS, Monaghan TM. RNA-Seq of untreated wastewater to assess COVID-19 and emerging and endemic viruses for public health surveillance. THE LANCET REGIONAL HEALTH. SOUTHEAST ASIA 2023; 14:100205. [PMID: 37193348 PMCID: PMC10150210 DOI: 10.1016/j.lansea.2023.100205] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 04/10/2023] [Accepted: 04/24/2023] [Indexed: 05/18/2023]
Abstract
Background The COVID-19 pandemic showcased the power of genomic sequencing to tackle the emergence and spread of infectious diseases. However, metagenomic sequencing of total microbial RNAs in wastewater has the potential to assess multiple infectious diseases simultaneously and has yet to be explored. Methods A retrospective RNA-Seq epidemiological survey of 140 untreated composite wastewater samples was performed across urban (n = 112) and rural (n = 28) areas of Nagpur, Central India. Composite wastewater samples were prepared by pooling 422 individual grab samples collected prospectively from sewer lines of urban municipality zones and open drains of rural areas from 3rd February to 3rd April 2021, during the second COVID-19 wave in India. Samples were pre-processed and total RNA was extracted prior to genomic sequencing. Findings This is the first study that has utilised culture and/or probe-independent unbiased RNA-Seq to examine Indian wastewater samples. Our findings reveal the detection of zoonotic viruses including chikungunya, Jingmen tick and rabies viruses, which have not previously been reported in wastewater. SARS-CoV-2 was detectable in 83 locations (59%), with stark abundance variations observed between sampling sites. Hepatitis C virus was the most frequently detected infectious virus, identified in 113 locations and co-occurring 77 times with SARS-CoV-2; and both were more abundantly detected in rural areas than urban zones. Concurrent identification of segmented virus genomic fragments of influenza A virus, norovirus, and rotavirus was observed. Geographical differences were also observed for astrovirus, saffold virus, husavirus, and aichi virus that were more prevalent in urban samples, while the zoonotic viruses chikungunya and rabies, were more abundant in rural environments. Interpretation RNA-Seq can effectively detect multiple infectious diseases simultaneously, facilitating geographical and epidemiological surveys of endemic viruses that could help direct healthcare interventions against emergent and pre-existent infectious diseases as well as cost-effectively and qualitatively characterising the health status of the population over time. Funding UK Research and Innovation (UKRI) Global Challenges Research Fund (GCRF) grant number H54810, as supported by Research England.
Collapse
Affiliation(s)
| | - Adam M. Blanchard
- School of Veterinary Medicine and Science, University of Nottingham, Nottingham, United Kingdom
| | - Amit Nayak
- Research Centre, Dr G.M. Taori Central India Institute of Medical Sciences (CIIMS), Nagpur, Maharashtra, India
| | - Aliabbas Husain
- Research Centre, Dr G.M. Taori Central India Institute of Medical Sciences (CIIMS), Nagpur, Maharashtra, India
| | - Rupam Nashine
- Research Centre, Dr G.M. Taori Central India Institute of Medical Sciences (CIIMS), Nagpur, Maharashtra, India
| | - Hemanshi Dudani
- Research Centre, Dr G.M. Taori Central India Institute of Medical Sciences (CIIMS), Nagpur, Maharashtra, India
| | - C. Patrick McClure
- National Institute for Health Research Nottingham Biomedical Research Centre, Nottingham University Hospitals National Health Service Trust, Nottingham, United Kingdom
- Wolfson Centre for Global Virus Research, University of Nottingham, Nottingham, United Kingdom
| | - Alexander W. Tarr
- National Institute for Health Research Nottingham Biomedical Research Centre, Nottingham University Hospitals National Health Service Trust, Nottingham, United Kingdom
- Wolfson Centre for Global Virus Research, University of Nottingham, Nottingham, United Kingdom
- Queen's Medical Centre, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Aditi Nag
- Dr. B. Lal Institute of Biotechnology, 6-E, Malviya Industrial Area, Malviya Nagar, Jaipur, India
| | - Ekta Meena
- Dr. B. Lal Institute of Biotechnology, 6-E, Malviya Industrial Area, Malviya Nagar, Jaipur, India
| | - Vikky Sinha
- Dr. B. Lal Institute of Biotechnology, 6-E, Malviya Industrial Area, Malviya Nagar, Jaipur, India
| | - Sandeep K. Shrivastava
- Centre for Innovation, Research & Development, Dr. B. Lal Clinical Laboratory Pvt. Ltd., Malviya Industrial Area, Malviya Nagar, Jaipur, India
| | - Colin Hill
- APC Microbiome Ireland, University College Cork, Co. Cork, Ireland
| | - Andrew C. Singer
- UK Centre for Ecology and Hydrology, Wallingford, United Kingdom
| | - Rachel L. Gomes
- Food Water Waste Research Group, Faculty of Engineering, University of Nottingham, United Kingdom
| | - Edward Acheampong
- Food Water Waste Research Group, Faculty of Engineering, University of Nottingham, United Kingdom
- Department of Statistics and Actuarial Science, University of Ghana, P.O. Box, LG 115, Legon, Ghana
| | - Saravana B. Chidambaram
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru, 570015, KA, India
| | - Tarun Bhatnagar
- ICMR-National Institute of Epidemiology, Chennai, Tamil Nadu, India
| | - Umashankar Vetrivel
- National Institute of Traditional Medicine, Indian Council of Medical Research, Belagavi, 590010, India
- Virology and Biotechnology Division, ICMR-National Institute for Research in Tuberculosis, Chennai, 600031, India
| | - Sudipti Arora
- Dr. B. Lal Institute of Biotechnology, 6-E, Malviya Industrial Area, Malviya Nagar, Jaipur, India
| | - Rajpal Singh Kashyap
- Research Centre, Dr G.M. Taori Central India Institute of Medical Sciences (CIIMS), Nagpur, Maharashtra, India
| | - Tanya M. Monaghan
- National Institute for Health Research Nottingham Biomedical Research Centre, Nottingham University Hospitals National Health Service Trust, Nottingham, United Kingdom
- Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| |
Collapse
|
2
|
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.
Collapse
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.
| |
Collapse
|
3
|
Arabi TZ, Sabbah BN, Lerman A, Zhu XY, Lerman LO. Xenotransplantation: Current Challenges and Emerging Solutions. Cell Transplant 2023; 32:9636897221148771. [PMID: 36644844 PMCID: PMC9846288 DOI: 10.1177/09636897221148771] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
To address the ongoing shortage of organs available for replacement, xenotransplantation of hearts, corneas, skin, and kidneys has been attempted. However, a major obstacle facing xenotransplants is rejection due to a cycle of immune reactions to the graft. Both adaptive and innate immune systems contribute to this cycle, in which natural killer cells, macrophages, and T-cells play a significant role. While advancements in the field of genetic editing can circumvent some of these obstacles, biomarkers to identify and predict xenograft rejection remain to be standardized. Several T-cell markers, such as CD3, CD4, and CD8, are useful in both the diagnosis and prediction of xenograft rejection. Furthermore, an increase in the levels of various circulating DNA markers and microRNAs is also predictive of xenograft rejection. In this review, we summarize recent findings on the advancements in xenotransplantation, with a focus on pig-to-human, the role of immunity in xenograft rejection, and its biomarkers.
Collapse
Affiliation(s)
- Tarek Ziad Arabi
- Division of Nephrology and
Hypertension, Mayo Clinic, Rochester, MN, USA,College of Medicine, Alfaisal
University, Riyadh, Saudi Arabia
| | - Belal Nedal Sabbah
- College of Medicine, Alfaisal
University, Riyadh, Saudi Arabia,Department of Urology, Mayo Clinic,
Rochester, MN, USA
| | - Amir Lerman
- Department of Cardiology, Mayo Clinic,
Rochester, MN, USA
| | - Xiang-Yang Zhu
- Division of Nephrology and
Hypertension, Mayo Clinic, Rochester, MN, USA,Xiang-Yang Zhu, Division of Nephrology and
Hypertension, Mayo Clinic, 200 First Street SW., Rochester, MN 55905, USA.
| | - Lilach O. Lerman
- Division of Nephrology and
Hypertension, Mayo Clinic, Rochester, MN, USA
| |
Collapse
|
4
|
Denner J. Virus Safety of Xenotransplantation. Viruses 2022; 14:1926. [PMID: 36146732 PMCID: PMC9503113 DOI: 10.3390/v14091926] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [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.
Collapse
Affiliation(s)
- Joachim Denner
- Institute of Virology, Free University Berlin, 14163 Berlin, Germany
| |
Collapse
|
5
|
Wadiwala IJ, Garg P, Yazji JH, Alamouti-fard E, Alomari M, Hussain MWA, Elawady MS, Jacob S. Evolution of Xenotransplantation as an Alternative to Shortage of Donors in Heart Transplantation. Cureus 2022; 14:e26284. [PMID: 35754438 PMCID: PMC9230910 DOI: 10.7759/cureus.26284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/23/2022] [Indexed: 12/03/2022] Open
Abstract
This review aims to show and illustrate the history, current, ethical considerations, and limitations concerning xenotransplantation. Due to the current shortage of available donor organs for transplantation, many alternative sources are being examined to solve the donor shortage. One of them is xenotransplantation which refers to the transplantation of organs from one species to another. Compared to other nonhuman primates (NHP), pigs are ideal species for organ harvesting as they rapidly grow to human size in a handful of months. There is much advancement in the genetic engineering of pigs, which have hearts structurally and functionally similar to the human heart. The role of genetic engineering is to overcome the immune barriers in xenotransplantation and can be used in hyperacute rejection and T cell-mediated rejection. It is technically difficult to use large animal models for orthotopic, life-sustaining heart transplantation. Despite the fact that some religious traditions, such as Jewish and Muslim, prohibit the ingestion of pork products, few religious leaders consider that donating porcine organs is ethical because it saves human life. Although recent technologies have lowered the risk of a xenograft producing a novel virus that causes an epidemic, the risk still exists. It has major implications for the informed consent procedure connected with clinical research on heart xenotransplantation.
Collapse
|
6
|
Chen JQ, Zhang MP, Tong XK, Li JQ, Zhang Z, Huang F, Du HP, Zhou M, Ai HS, Huang LS. Scan of the endogenous retrovirus sequences across the swine genome and survey of their copy number variation and sequence diversity among various Chinese and Western pig breeds. Zool Res 2022; 43:423-441. [PMID: 35437972 PMCID: PMC9113972 DOI: 10.24272/j.issn.2095-8137.2021.379] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Accepted: 04/12/2022] [Indexed: 11/21/2022] Open
Abstract
In pig-to-human xenotransplantation, the transmission risk of porcine endogenous retroviruses (PERVs) is of great concern. However, the distribution of PERVs in pig genomes, their genetic variation among Eurasian pigs, and their evolutionary history remain unclear. We scanned PERVs in the current pig reference genome (assembly Build 11.1), and identified 36 long complete or near-complete PERVs (lcPERVs) and 23 short incomplete PERVs (siPERVs). Besides three known PERVs (PERV-A, -B, and -C), four novel types (PERV-JX1, -JX2, -JX3, and -JX4) were detected in this study. According to evolutionary analyses, the newly discovered PERVs were more ancient, and PERV-Bs probably experienced a bottleneck ~0.5 million years ago (Ma). By analyzing 63 high-quality porcine whole-genome resequencing data, we found that the PERV copy numbers in Chinese pigs were lower (32.0±4.0) than in Western pigs (49.1±6.5). Additionally, the PERV sequence diversity was lower in Chinese pigs than in Western pigs. Regarding the lcPERV copy numbers, PERV-A and -JX2 in Western pigs were higher than in Chinese pigs. Notably, Bama Xiang (BMX) pigs had the lowest PERV copy number (27.8±5.1), and a BMX individual had no PERV-C and the lowest PERV copy number (23), suggesting that BMX pigs were more suitable for screening and/or modification as xenograft donors. Furthermore, we identified 451 PERV transposon insertion polymorphisms (TIPs), of which 86 were shared by all 10 Chinese and Western pig breeds. Our findings provide systematic insights into the genomic distribution, variation, evolution, and possible biological function of PERVs.
Collapse
Affiliation(s)
- Jia-Qi Chen
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, China
| | - Ming-Peng Zhang
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, China
| | - Xin-Kai Tong
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, China
| | - Jing-Quan Li
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, China
| | - Zhou Zhang
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, China
| | - Fei Huang
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, China
| | - Hui-Peng Du
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, China
| | - Meng Zhou
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, China
| | - Hua-Shui Ai
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, China. E-mail:
| | - Lu-Sheng Huang
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, China. E-mail:
| |
Collapse
|
7
|
Denner J. Porcine Endogenous Retroviruses and Xenotransplantation, 2021. Viruses 2021; 13:v13112156. [PMID: 34834962 PMCID: PMC8625113 DOI: 10.3390/v13112156] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [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.
Collapse
Affiliation(s)
- Joachim Denner
- Department of Veterinary Medicine, Institute of Virology, Free University Berlin, 14163 Berlin, Germany
| |
Collapse
|
8
|
Yoon CH, Choi HJ, Kim MK. Corneal xenotransplantation: Where are we standing? Prog Retin Eye Res 2021; 80:100876. [PMID: 32755676 PMCID: PMC7396149 DOI: 10.1016/j.preteyeres.2020.100876] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 05/23/2020] [Accepted: 06/04/2020] [Indexed: 02/08/2023]
Abstract
The search for alternatives to allotransplants is driven by the shortage of corneal donors and is demanding because of the limitations of the alternatives. Indeed, current progress in genetically engineered (GE) pigs, the introduction of gene-editing technology by clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9, and advanced immunosuppressants have made xenotransplantation a possible option for a human trial. Porcine corneal xenotransplantation is considered applicable because the eye is regarded as an immune-privileged site. Furthermore, recent non-human primate studies have shown long-term survival of porcine xenotransplants in keratoplasty. Herein, corneal immune privilege is briefly introduced, and xenogeneic reactions are compared with allogeneic reactions in corneal transplantation. This review describes the current knowledge on special issues of xenotransplantation, xenogeneic rejection mechanisms, current immunosuppressive regimens of corneal xenotransplantation, preclinical efficacy and safety data of corneal xenotransplantation, and updates of the regulatory framework to conduct a clinical trial on corneal xenotransplantation. We also discuss barriers that might prevent xenotransplantation from becoming common practice, such as ethical dilemmas, public concerns on xenotransplantation, and the possible risk of xenozoonosis. Given that the legal definition of decellularized porcine cornea (DPC) lies somewhere between a medical device and a xenotransplant, the preclinical efficacy and clinical trial data using DPC are included. The review finally provides perspectives on the current standpoint of corneal xenotransplantation in the fields of regenerative medicine.
Collapse
Affiliation(s)
- Chang Ho Yoon
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Republic of Korea; Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Republic of Korea
| | - Hyuk Jin Choi
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Republic of Korea; Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Republic of Korea; Department of Ophthalmology, Seoul National University Hospital Healthcare System Gangnam Center, Seoul, Republic of Korea
| | - Mee Kum Kim
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Republic of Korea; Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Republic of Korea.
| |
Collapse
|
9
|
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: 23] [Impact Index Per Article: 7.7] [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.
Collapse
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.
| |
Collapse
|
10
|
Kono K, Kataoka K, Yuan Y, Yusa K, Uchida K, Sato Y. A highly sensitive method for the detection of recombinant PERV-A/C env RNA using next generation sequencing technologies. Sci Rep 2020; 10:21935. [PMID: 33318655 PMCID: PMC7736861 DOI: 10.1038/s41598-020-78890-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 11/30/2020] [Indexed: 12/27/2022] Open
Abstract
Several xenogenic cell-based therapeutic products are currently under development around the world for the treatment of human diseases. Porcine islet cell products for treating human diabetes are a typical example. Since porcine cells possess endogenous retrovirus (PERV), which can replicate in human cells in vitro, the potential transmission of PERV has raised concerns in the development of these products. Four subgroups of infectious PERV have been identified, namely PERV-A, -B, -C, and recombinant PERV-A/C. Among them, PERV-A/C shows a high titre and there was a paper reported that an incidence of PERV-A/C viremia was increased in diseased pigs; thus, it would be important to monitor the emergence of PERV-A/C after transplantation of porcine products. In this study, we developed a highly sensitive method for the detection of PERV-A/C using next generation sequencing (NGS) technologies. A model PERV-C spiked with various doses of PERV-A/C were amplified by RT-PCR and the amplicons were analysed by NGS. We found that the NGS analysis allowed the detection of PERV-A/C at the abundance ratios of 1% and 0.1% with true positive rates of 100% and 57%, respectively, indicating that it would be useful for the rapid detection of PERV-A/C emergence after transplantation of porcine products.
Collapse
Affiliation(s)
- Ken Kono
- Division of Cell-Based Therapeutic Products, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki Ward, Kawasaki City, Kanagawa, 210-9501, Japan
| | - Kiyoko Kataoka
- Division of Cell-Based Therapeutic Products, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki Ward, Kawasaki City, Kanagawa, 210-9501, Japan
| | - Yuzhe Yuan
- Graduate School of Science, Technology and Innovation, Kobe University, Hyogo, Japan
| | - Keisuke Yusa
- Graduate School of Science, Technology and Innovation, Kobe University, Hyogo, Japan
| | - Kazuhisa Uchida
- Graduate School of Science, Technology and Innovation, Kobe University, Hyogo, Japan
| | - Yoji Sato
- Division of Cell-Based Therapeutic Products, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki Ward, Kawasaki City, Kanagawa, 210-9501, Japan. .,Department of Translational Pharmaceutical Sciences, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan. .,Department of Cellular and Gene Therapy Products, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan.
| |
Collapse
|
11
|
Chen Y, Chen M, Duan X, Cui J. Ancient origin and complex evolution of porcine endogenous retroviruses. BIOSAFETY AND HEALTH 2020. [DOI: 10.1016/j.bsheal.2020.03.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
|
12
|
Krüger L, Stillfried M, Prinz C, Schröder V, Neubert LK, Denner J. Copy Number and Prevalence of Porcine Endogenous Retroviruses (PERVs) in German Wild Boars. Viruses 2020; 12:v12040419. [PMID: 32276520 PMCID: PMC7232352 DOI: 10.3390/v12040419] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/02/2020] [Accepted: 04/04/2020] [Indexed: 01/25/2023] Open
Abstract
Porcine endogenous retroviruses (PERVs) are integrated in the genome of pigs and are transmitted like cellular genes from parents to the offspring. Whereas PERV-A and PERV-B are present in all pigs, PERV-C was found to be in many, but not all pigs. When PERV-C is present, recombination with PERV-A may happen and the PERV-A/C recombinants are characterized by a high replication rate. Until now, nothing has been known about the copy number of PERVs in wild boars and little is known about the prevalence of the phylogenetically youngest PERV-C in ancient wild boars. Here we investigated for the first time the copy number of PERVs in different populations of wild boars in and around Berlin using droplet digital PCR. Copy numbers between 3 and 69 per genome have been measured. A lower number but a higher variability was found compared to domestic pigs, including minipigs reported earlier (Fiebig et al., Xenotransplantation, 2018). The wild boar populations differed genetically and had been isolated during the existence of the Berlin wall. Despite this, the variations in copy number were larger in a single population compared to the differences between the populations. PERV-C was found in all 92 analyzed animals. Differences in the copy number of PERV in different organs of a single wild boar indicate that PERVs are also active in wild boars, replicating and infecting new cells as has been shown in domestic pigs.
Collapse
Affiliation(s)
- Luise Krüger
- Robert Koch Fellow, Robert Koch Institute, 13353 Berlin, Germany; (L.K.); (C.P.); (V.S.); (L.K.N.)
| | - Milena Stillfried
- Department of Ecological Dynamics, Leibniz Institute for Zoo and Wildlife Research, 10315 Berlin, Germany;
| | - Carolin Prinz
- Robert Koch Fellow, Robert Koch Institute, 13353 Berlin, Germany; (L.K.); (C.P.); (V.S.); (L.K.N.)
| | - Vanessa Schröder
- Robert Koch Fellow, Robert Koch Institute, 13353 Berlin, Germany; (L.K.); (C.P.); (V.S.); (L.K.N.)
| | - Lena Katharina Neubert
- Robert Koch Fellow, Robert Koch Institute, 13353 Berlin, Germany; (L.K.); (C.P.); (V.S.); (L.K.N.)
| | - Joachim Denner
- Robert Koch Fellow, Robert Koch Institute, 13353 Berlin, Germany; (L.K.); (C.P.); (V.S.); (L.K.N.)
- Correspondence: ; Tel.: +49-30-18754-2800
| |
Collapse
|
13
|
Lu T, Yang B, Wang R, Qin C. Xenotransplantation: Current Status in Preclinical Research. Front Immunol 2020; 10:3060. [PMID: 32038617 PMCID: PMC6989439 DOI: 10.3389/fimmu.2019.03060] [Citation(s) in RCA: 116] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 12/16/2019] [Indexed: 12/13/2022] Open
Abstract
The increasing life expectancy of humans has led to a growing numbers of patients with chronic diseases and end-stage organ failure. Transplantation is an effective approach for the treatment of end-stage organ failure; however, the imbalance between organ supply and the demand for human organs is a bottleneck for clinical transplantation. Therefore, xenotransplantation might be a promising alternative approach to bridge the gap between the supply and demand of organs, tissues, and cells; however, immunological barriers are limiting factors in clinical xenotransplantation. Thanks to advances in gene-editing tools and immunosuppressive therapy as well as the prolonged xenograft survival time in pig-to-non-human primate models, clinical xenotransplantation has become more viable. In this review, we focus on the evolution and current status of xenotransplantation research, including our current understanding of the immunological mechanisms involved in xenograft rejection, genetically modified pigs used for xenotransplantation, and progress that has been made in developing pig-to-pig-to-non-human primate models. Three main types of rejection can occur after xenotransplantation, which we discuss in detail: (1) hyperacute xenograft rejection, (2) acute humoral xenograft rejection, and (3) acute cellular rejection. Furthermore, in studies on immunological rejection, genetically modified pigs have been generated to bridge cross-species molecular incompatibilities; in the last decade, most advances made in the field of xenotransplantation have resulted from the production of genetically engineered pigs; accordingly, we summarize the genetically modified pigs that are currently available for xenotransplantation. Next, we summarize the longest survival time of solid organs in preclinical models in recent years, including heart, liver, kidney, and lung xenotransplantation. Overall, we conclude that recent achievements and the accumulation of experience in xenotransplantation mean that the first-in-human clinical trial could be possible in the near future. Furthermore, we hope that xenotransplantation and various approaches will be able to collectively solve the problem of human organ shortage.
Collapse
Affiliation(s)
- Tianyu Lu
- Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China.,NHC Key Laboratory of Human Disease Comparative Medicine, The Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.,Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, Beijing, China
| | - Bochao Yang
- Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China.,NHC Key Laboratory of Human Disease Comparative Medicine, The Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.,Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, Beijing, China
| | - Ruolin Wang
- Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China.,NHC Key Laboratory of Human Disease Comparative Medicine, The Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.,Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, Beijing, China
| | - Chuan Qin
- Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China.,NHC Key Laboratory of Human Disease Comparative Medicine, The Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.,Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, Beijing, China
| |
Collapse
|
14
|
Chung HC, Nguyen VG, Moon HJ, Park YH, Park BK. Regulation of porcine endogenous retrovirus by dual LTR1+2 (Long Terminal Region) miRNA in primary porcine kidney cells. J Vet Sci 2020; 20:e50. [PMID: 31565893 PMCID: PMC6769330 DOI: 10.4142/jvs.2019.20.e50] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 06/18/2019] [Accepted: 08/05/2019] [Indexed: 11/20/2022] Open
Abstract
Porcine endogenous retroviruses (PERVs) integrate into germline DNA as proviral genome that enables vertical transmission from parents to their offspring. The provirus usually survives as part of the host genome rather than as an infectious agent, but may become pathogenic if it crosses species barriers. Therefore, replication-competent PERV should be controlled through selective breeding or knockout technologies. Two microRNAs (miRNAs), dual LTR1 and LTR2, were selected to inhibit the expression of PERV in primary porcine kidney cells. The inhibition efficiency of the miRNAs was compared based on their inhibition of different PERV regions, specifically long terminal repeats (LTRs), gag, pol, and env. Gene expression was quantified using real-time polymerase chain reaction and the C-type reverse transcriptase (RT) activity was determined. The messenger RNA (mRNA) expression of the PERV LTR and env regions was determined in HeLa cells co-cultured with primary porcine kidney cells. The mRNA expression of the LTR, gag, pol, and env regions of PERV was dramatically inhibited by dual miRNA from 24 to 144 h after transfection, with the highest inhibition observed for the LTR and pol regions at 120 h. Additionally, the RT activity of PERV in the co-culture experiment of porcine and human cells was reduced by 84.4% at the sixth passage. The dual LTR 1+2 miRNA efficiently silences PERV in primary porcine kidney cells.
Collapse
Affiliation(s)
- Hee Chun Chung
- Department of Veterinary Medicine Virology Lab, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea
| | - Van Giap Nguyen
- Department of Veterinary Microbiology and Infectious Diseases, Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Hanoi 100000, Vietnam
| | - Hyung Joon Moon
- Research Unit, Green Cross Veterinary Products, Yongin 17066, Korea
| | - Yong Ho Park
- Department of Veterinary Microbiology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea.
| | - Bong Kyun Park
- Department of Veterinary Medicine Virology Lab, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Korea.
| |
Collapse
|
15
|
Zhang Y, Xing X, Huang L, Wu Y, Li P, Li R, Liu G. Screening pigs for xenotransplantation in China: investigation of porcine endogenous retrovirus in Diannan small-eared pigs. Virus Genes 2020; 56:202-208. [PMID: 31916138 DOI: 10.1007/s11262-019-01722-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 12/12/2019] [Indexed: 12/28/2022]
Abstract
Porcine endogenous retrovirus (PERV), which integrates as a provirus into the genome of pig cells, is an important biosafety issue in xenotransplantation. Screening and analyzing the presence and expression of PERV will provide essential parameters for assessing the biosafety of donor sources. In the present study, we investigated the prevalence of PERV in Diannan small-eared pigs, a unique closed colony that is distributed in southern Yunnan Province in southwestern China. PCR was performed to amplify env-A, env-B, env-C, pol, gag, and mtDNA in peripheral blood samples. The results revealed that PERV env-A, env-B, pol, and gag were detected in all individuals, but env-C was deficient in most pigs, suggesting that the main subtypes of PERVs in Diannan small-eared pigs are PERV-A and PERV-B. Furthermore, PERV pol and the porcine housekeeping gene GAPDH were detected by RT-PCR in all peripheral blood samples, indicating that PERV had transcriptional activity. Finally, the consensus sequences of PERV-A and PERV-B were amplified and digested with KpnI and MboI. Interestingly, a total of seven digestion patterns were obtained, which is less than that observed in other pig breeds. The PCR products were cloned into the pUCm-T vector and sequenced. The results showed that all of the inserts were highly homologous to either PERV-A or PERV-B, and the ratios of PERV-A and PERV-B were 21.1% and 78.9%, respectively. These data suggest that Diannan small-eared pigs may be a candidate donor source for xenotransplantation.
Collapse
Affiliation(s)
- Yunfei Zhang
- Center for Medical Experiments, The Third Xiangya Hospital, Central South University, Changsha, 410013, Hunan, China
| | - Xiaowei Xing
- Center for Medical Experiments, The Third Xiangya Hospital, Central South University, Changsha, 410013, Hunan, China
| | - Lihua Huang
- Center for Medical Experiments, The Third Xiangya Hospital, Central South University, Changsha, 410013, Hunan, China
| | - Yong Wu
- Clinical Laboratory, The Third Xiangya Hospital, Central South University, Changsha, 410013, Hunan, China
| | - Peng Li
- Department of General Surgery, Yanan Hospital Affiliated to Kunming Medical University, Kunming, 650051, Yunnan, China
| | - Ruhong Li
- Department of General Surgery, Yanan Hospital Affiliated to Kunming Medical University, Kunming, 650051, Yunnan, China.
| | - Gang Liu
- The Institute of Reproduction and Stem Cell Engineering, Central South University, Changsha, 410078, Hunan, China.
| |
Collapse
|
16
|
Development of conventional and real time PCR assays for rapid species authentication of mammalian cell lines commonly used in veterinary diagnostic laboratories. Res Vet Sci 2019; 126:170-177. [PMID: 31505453 DOI: 10.1016/j.rvsc.2019.08.029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 08/21/2019] [Accepted: 08/27/2019] [Indexed: 12/19/2022]
Abstract
Mammalian cell lines are valuable tools in biomedical fields, with applications ranging from disease diagnosis to the production of biological reagents and vaccines. Here we report the development of new conventional (cPCR) and real time PCR (qPCR) assays for species identification of several mammalian kidney cell lines originated from swine, green monkey, hamster and bovine tissues that are extensively used in veterinary diagnostic laboratories. The PCR primers and probes were selected from highly conserved mitochondrial genes and analyzed in silico by nucleotide BLAST in the National Center for Biotechnology Information (NCBI) website to ensure target specificity. The assays were highly species-specific and had no cross-reactivity against other tested cell lines originated from different mammalian species. Assay sensitivity (limit of detection; LOD) was determined using serial dilutions of cell line DNA as template. The estimated LODs were between 2.95 and 48 pg (picogram) DNA/assay for cPCR, and between 1.5 × 10-3 and 4.8 × 10-2 pg DNA/assay for qPCR. Multiplex qPCR assays were developed for simultaneous detection of up to three species in a single assay. The multiplex qPCR assays exhibited the same sensitivity as the corresponding singleplex assays with the exception of the green monkey species that demonstrated a 10-100 fold decline in the sensitivity. Contamination of swine cells was detected in one of the rabbit cell lines. The contamination was further confirmed by Sanger and Next-Generation sequencing.
Collapse
|
17
|
Fiebig U, Fischer K, Bähr A, Runge C, Schnieke A, Wolf E, Denner J. Porcine endogenous retroviruses: Quantification of the copy number in cell lines, pig breeds, and organs. Xenotransplantation 2018; 25:e12445. [DOI: 10.1111/xen.12445] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 06/07/2018] [Accepted: 06/26/2018] [Indexed: 12/12/2022]
Affiliation(s)
| | - Konrad Fischer
- School of Life Sciences Weihenstephan; Technische Universität München; Freising Germany
| | - Andrea Bähr
- Molecular Animal Breeding and Biotechnology; Gene Center; Ludwig-Maximilians-Universität München; Oberschleißheim Germany
| | | | - Angelika Schnieke
- School of Life Sciences Weihenstephan; Technische Universität München; Freising Germany
| | - Eckhard Wolf
- Molecular Animal Breeding and Biotechnology; Gene Center; Ludwig-Maximilians-Universität München; Oberschleißheim Germany
| | | |
Collapse
|
18
|
Abstract
The growing shortage of available organs is a major problem in transplantology. Thus, new and alternative sources of organs need to be found. One promising solution could be xenotransplantation, i.e., the use of animal cells, tissues and organs. The domestic pig is the optimum donor for such transplants. However, xenogeneic transplantation from pigs to humans involves high immune incompatibility and a complex rejection process. The rapid development of genetic engineering techniques enables genome modifications in pigs that reduce the cross-species immune barrier.
Collapse
|
19
|
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: 15] [Impact Index Per Article: 2.5] [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.
Collapse
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
| |
Collapse
|
20
|
Matczyńska D, Sypniewski D, Gałka S, Sołtysik D, Loch T, Nowak E, Smorąg Z, Bednarek I. Analysis of swine leukocyte antigen class I gene profiles and porcine endogenous retrovirus viremia level in a transgenic porcine herd inbred for xenotransplantation research. J Vet Sci 2018; 19:384-392. [PMID: 29366300 PMCID: PMC5974520 DOI: 10.4142/jvs.2018.19.3.384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 12/29/2017] [Accepted: 01/20/2018] [Indexed: 11/26/2022] Open
Abstract
Molecular characterization of swine leukocyte antigen (SLA) genes is important for elucidating the immune responses between swine-donor and human-recipient in xenotransplantation. Examination of associations between alleles of SLA class I genes, type of pig genetic modification, porcine endogenous retrovirus (PERV) viral titer, and PERV subtypes may shed light on the nature of xenograft acceptance or rejection and the safety of xenotransplantation. No significant difference in PERV gag RNA level between transgenic and non-transgenic pigs was noted; likewise, the type of applied transgene had no impact on PERV viremia. SLA-1 gene profile type may correspond with PERV level in blood and thereby influence infectiveness. Screening of pigs should provide selection of animals with low PERV expression and exclusion of specimens with PERV-C in the genome due to possible recombination between A and C subtypes, which may lead to autoinfection. Presence of PERV-C integrated in the genome was detected in 31.25% of specimens, but statistically significant increased viremia in specimens with PERV-C was not observed. There is a need for multidirectional molecular characterization (SLA typing, viremia estimation, and PERV subtype screening) of animals intended for xenotransplantation research in the interest of xeno-recipient safety.
Collapse
Affiliation(s)
- Daria Matczyńska
- Department of Biotechnology and Genetic Engineering, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia in Katowice, 41-200 Sosnowiec, Poland
| | - Daniel Sypniewski
- Department of Biotechnology and Genetic Engineering, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia in Katowice, 41-200 Sosnowiec, Poland
| | - Sabina Gałka
- Department of Biotechnology and Genetic Engineering, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia in Katowice, 41-200 Sosnowiec, Poland
| | - Dagna Sołtysik
- Department of Biotechnology and Genetic Engineering, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia in Katowice, 41-200 Sosnowiec, Poland
| | - Tomasz Loch
- Department of Biotechnology and Genetic Engineering, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia in Katowice, 41-200 Sosnowiec, Poland
| | - Ewa Nowak
- Department of Biotechnology and Genetic Engineering, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia in Katowice, 41-200 Sosnowiec, Poland
| | - Zdzisław Smorąg
- Department of Animal Reproduction Biotechnology, National Research Institute of Animal Production, 32-083 Balice, Poland
| | - Ilona Bednarek
- Department of Biotechnology and Genetic Engineering, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia in Katowice, 41-200 Sosnowiec, Poland
| |
Collapse
|
21
|
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.
Collapse
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
| |
Collapse
|
22
|
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.
Collapse
Affiliation(s)
- Joachim Denner
- Robert Koch Institute, Nordufer 20, 13353, Berlin, Germany.
| |
Collapse
|
23
|
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: 21] [Impact Index Per Article: 3.0] [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
| | | |
Collapse
|
24
|
Scobie L, Denner J, Schuurman HJ. Inactivation of porcine endogenous retrovirus in pigs using CRISPR-Cas9, editorial commentary. Xenotransplantation 2017; 24. [DOI: 10.1111/xen.12363] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 09/21/2017] [Accepted: 10/13/2017] [Indexed: 12/19/2022]
Affiliation(s)
- Linda Scobie
- School of Health and Life Sciences; Glasgow Caledonian University; Glasgow UK
| | | | | |
Collapse
|
25
|
Denner J. The porcine virome and xenotransplantation. Virol J 2017; 14:171. [PMID: 28874166 PMCID: PMC5585927 DOI: 10.1186/s12985-017-0836-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 08/27/2017] [Indexed: 12/29/2022] Open
Abstract
The composition of the porcine virome includes viruses that infect pig cells, ancient virus-derived elements including endogenous retroviruses inserted in the pig chromosomes, and bacteriophages that infect a broad array of bacteria that inhabit pigs. Viruses infecting pigs, among them viruses also infecting human cells, as well as porcine endogenous retroviruses (PERVs) are of importance when evaluating the virus safety of xenotransplantation. Bacteriophages associated with bacteria mainly in the gut are not relevant in this context. Xenotransplantation using pig cells, tissues or organs is under development in order to alleviate the shortage of human transplants. Here for the first time published data describing the viromes in different pigs and their relevance for the virus safety of xenotransplantation is analysed. In conclusion, the analysis of the porcine virome has resulted in numerous new viruses being described, although their impact on xenotransplantation is unclear. Most importantly, viruses with known or suspected zoonotic potential were often not detected by next generation sequencing, but were revealed by more sensitive methods.
Collapse
Affiliation(s)
- Joachim Denner
- Robert Koch Fellow, Robert Koch Institute, Nordufer, 20, Berlin, Germany.
| |
Collapse
|
26
|
Choi HJ, Kim J, Kim JY, Lee HJ, Wee WR, Kim MK, Hwang ES. Long-term safety from transmission of porcine endogenous retrovirus after pig-to-non-human primate corneal transplantation. Xenotransplantation 2017; 24. [PMID: 28503733 DOI: 10.1111/xen.12314] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 04/07/2017] [Accepted: 04/10/2017] [Indexed: 12/31/2022]
Abstract
BACKGROUND The risk of xenozoonosis mainly by porcine endogenous retrovirus (PERV) has been considered as one of the main hurdles in xenotransplantation and therefore should be elucidated prior to the clinical use of porcine corneal grafts. Accordingly, an investigation was performed to analyze the infectivity of PERVs from porcine keratocytes to human cells, and the long-term risk of transmission of PERVs was determined using pig-to-non-human primate (NHP) corneal transplantation models. METHODS The infectivity of PERVs from the SNU miniature pig keratocytes was investigated by coculture with a human embryonic kidney cell line. Twenty-two rhesus macaques underwent xenocorneal transplantation as follows: (i) group 1 (n=4): anterior lamellar keratoplasty (LKP) with freshly preserved porcine corneas, (ii) group 2 (n=5): anterior LKP with decellularized porcine corneas followed by penetrating keratoplasty (PKP) with allografts, (iii) group 3 (n=3): PKP under steroid-based immunosuppression, (iv) group 4 (n=4): PKP under anti-CD154 antibody-based immunosuppression, (v) group 5 (n=4): deep anterior LKP with freshly preserved porcine corneas under anti-CD40 antibody-based immunosuppression, and (vi) group 6 (n=2): PKP under anti-CD40 antibody-based immunosuppression. Postoperative blood samples were serially collected, and tissue samples were obtained from thirteen different organs at the end of each experiment. The existence of PERV DNA and RNA was investigated using PCR and RT-PCR. RESULTS Using two independent in vitro infectivity tests, neither PERV pol nor pig mitochondrial cytochrome oxidase II was detected after 41 and 92 days of coculture, respectively. After xenocorneal transplantation, a total of 257 serial peripheral blood mononuclear cell samples, 34 serial plasma samples, and 282 tissue samples were obtained from the NHP recipients up to 1176 days post-transplantation. No PERV transmission was evident in any samples. CONCLUSIONS Within the limits of this study, there is no evidence to support any risk of PERV transmission from porcine corneal tissues to NHP recipients, despite the existence of PERV-expressing cells in porcine corneas.
Collapse
Affiliation(s)
- Hyuk Jin Choi
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea.,Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Korea.,Xenotransplantation Research Center, Seoul National University Hospital, Seoul, Korea
| | - Jiyeon Kim
- Xenotransplantation Research Center, Seoul National University Hospital, Seoul, Korea.,Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Korea
| | - Jae Young Kim
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea.,Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Korea.,Xenotransplantation Research Center, Seoul National University Hospital, Seoul, Korea
| | - Hyun Ju Lee
- Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Korea.,Xenotransplantation Research Center, Seoul National University Hospital, Seoul, Korea
| | - Won Ryang Wee
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea.,Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Korea.,Xenotransplantation Research Center, Seoul National University Hospital, Seoul, Korea
| | - Mee Kum Kim
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea.,Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Korea.,Xenotransplantation Research Center, Seoul National University Hospital, Seoul, Korea
| | - Eung Soo Hwang
- Xenotransplantation Research Center, Seoul National University Hospital, Seoul, Korea.,Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Korea
| |
Collapse
|
27
|
How Active Are Porcine Endogenous Retroviruses (PERVs)? Viruses 2016; 8:v8080215. [PMID: 27527207 PMCID: PMC4997577 DOI: 10.3390/v8080215] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 07/04/2016] [Accepted: 07/22/2016] [Indexed: 01/12/2023] Open
Abstract
Porcine endogenous retroviruses (PERVs) represent a risk factor if porcine cells, tissues, or organs were to be transplanted into human recipients to alleviate the shortage of human transplants; a procedure called xenotransplantation. In contrast to human endogenous retroviruses (HERVs), which are mostly defective and not replication-competent, PERVs are released from normal pig cells and are infectious. PERV-A and PERV-B are polytropic viruses infecting cells of several species, among them humans; whereas PERV-C is an ecotropic virus infecting only pig cells. Virus infection was shown in co-culture experiments, but also in vivo, in the pig, leading to de novo integration of proviruses in certain organs. This was shown by measurement of the copy number per cell, finding different numbers in different organs. In addition, recombinations between PERV-A and PERV-C were observed and the recombinant PERV-A/C were found to be integrated in cells of different organs, but not in the germ line of the animals. Here, the evidence for such in vivo activities of PERVs, including expression as mRNA, protein and virus particles, de novo infection and recombination, will be summarised. These activities make screening of pigs for provirus number and PERV expression level difficult, especially when only blood or ear biopsies are available for analysis. Highly sensitive methods to measure the copy number and the expression level will be required when selecting pigs with low copy number and low expression of PERV as well as when inactivating PERVs using the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated nuclease (CRISPR/Cas) technology.
Collapse
|
28
|
Yoon JK, Choi J, Lee HJ, Cho Y, Gwon YD, Jang Y, Kim S, Choi H, Lee JH, Kim YB. Distribution of Porcine Endogenous Retrovirus in Different Organs of the Hybrid of a Landrace and a Jeju Domestic Pig in Korea. Transplant Proc 2016; 47:2067-71. [PMID: 26293098 DOI: 10.1016/j.transproceed.2015.05.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 05/22/2015] [Indexed: 01/30/2023]
Abstract
Xenotransplantation offers a solution to the shortage of available organs for transplantation, and the pig represents an ideal source of such organs. However, porcine endogenous retrovirus (PERV), whose genome is integrated in pigs, has been suggested to pose a potential risk of xenotransmission. Expression of PERVs in different organs of pigs was carefully measured at DNA, mRNA, and protein levels, providing information valuable for the application of pig organs in xenotransplantation. An analysis of PERV DNA showed that a very similar number of PERV copies was present in the genome of all organs, whereas mRNA and protein levels of PERV varied depending on the organ, with kidney, liver, and spleen expressing high levels of both mRNA and protein. In contrast, mRNA and protein levels were dissimilar in the lung and brain, where mRNA levels were low but protein levels were high. This discrepancy indicates that mRNA levels are not always reflected in protein expression. In addition, the difference between mRNA and protein highlights the importance of choosing the proper analysis method for diagnosing viral infection. In summary, this study provides insight into the distribution of PERV in various organs at the DNA, mRNA, and protein levels, and also informs the proper selection of tissues or organs for future clinical xenotransplantation.
Collapse
Affiliation(s)
- J K Yoon
- Department of Bio-industrial Technologies, Konkuk University, Seoul, Korea
| | - J Choi
- Department of Bio-industrial Technologies, Konkuk University, Seoul, Korea
| | - H J Lee
- Department of Bio-industrial Technologies, Konkuk University, Seoul, Korea
| | - Y Cho
- Department of Bio-industrial Technologies, Konkuk University, Seoul, Korea
| | - Y D Gwon
- Department of Bio-industrial Technologies, Konkuk University, Seoul, Korea
| | - Y Jang
- Department of Bio-industrial Technologies, Konkuk University, Seoul, Korea
| | - S Kim
- Department of Bio-industrial Technologies, Konkuk University, Seoul, Korea
| | - H Choi
- Department of Bio-industrial Technologies, Konkuk University, Seoul, Korea
| | - J H Lee
- College of Veterinary Medicine, Konkuk University, Seoul, Korea
| | - Y B Kim
- Department of Bio-industrial Technologies, Konkuk University, Seoul, Korea.
| |
Collapse
|
29
|
Plotzki E, Heinrichs G, Kubícková B, Ulrich RG, Denner J. Microbiological characterization of a newly established pig breed, Aachen Minipigs. Xenotransplantation 2016; 23:159-67. [PMID: 26991265 DOI: 10.1111/xen.12233] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 02/15/2016] [Indexed: 11/29/2022]
Abstract
BACKGROUND To alleviate the shortage of human donor organs or tissues for the treatment of organ and tissue failure including diabetes, pigs are considered suitable donor animals. As organs from conventional pigs are usually too large, those from minipigs may be better suited. We recently characterized the Göttingen Minipigs, a breed well characterized concerning the presence of zoonotic microorganisms and found hepatitis E virus (HEV) and porcine cytomegalovirus (PCMV) in some animals. Here, we characterize another minipig, the Aachen Minipig (AaMP), a pig breed recently established close to the town Aachen in Germany. METHODS The animals were tested for the prevalence and expression of porcine endogenous retroviruses (PERVs) and the presence of some selected microorganisms, among them HEV, PCMV, and porcine lymphotropic herpesviruses (PLHVs) using highly sensitive and specific PCR and RT-PCR methods. In addition, we screened for antibodies against HEV and PLHV. RESULTS PERV-A, PERV-B, and PERV-C sequences were found in the genome of all Aachen Minipigs. HEV RNA was found by real-time RT-PCR in most, and DNA of PCMV, PLHV-2, and PLHV-3 was found by PCR in some animals. The animals were free of eight other microorganisms tested, but some were seropositive for porcine circovirus 2 (PCV2), porcine reproductive and respiratory syndrome virus (PRRSV), and porcine epidemic diarrhea virus (PEDV). CONCLUSION Based on medical examinations by veterinarians, the AaMP are in a good health status and seem to harbor only few microorganisms. To improve their status for use as donor pigs in xenotransplantation, the viruses detected might be eliminated by selection of negative animals, Cesarean section, and vaccination.
Collapse
Affiliation(s)
- Elena Plotzki
- Robert Koch Institute, HIV and other Retroviruses, Berlin, Germany
| | | | - Barbara Kubícková
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute for Novel and Emerging Infectious Diseases, Greifswald - Insel Riems, Germany
| | - Rainer G Ulrich
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute for Novel and Emerging Infectious Diseases, Greifswald - Insel Riems, Germany
| | - Joachim Denner
- Robert Koch Institute, HIV and other Retroviruses, Berlin, Germany
| |
Collapse
|
30
|
Denner J, Tönjes RR, Takeuchi Y, Fishman J, Scobie L. First update of the International Xenotransplantation Association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes-Chapter 5: recipient monitoring and response plan for preventing disease trans. Xenotransplantation 2016; 23:53-9. [DOI: 10.1111/xen.12227] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 02/08/2016] [Indexed: 12/20/2022]
Affiliation(s)
| | | | - Yasu Takeuchi
- Division of Infection and Immunity; University College; London UK
| | - Jay Fishman
- Infectious Disease Division; Massachusetts General Hospital; Boston MA USA
| | | |
Collapse
|
31
|
Denner J, Petersen B, Niemann H. Tolerance and immune response to the porcine endogenous retrovirus in German landrace pigs immunised with viral proteins. Virus Res 2015; 208:39-43. [PMID: 26043980 DOI: 10.1016/j.virusres.2015.05.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 05/20/2015] [Accepted: 05/22/2015] [Indexed: 12/12/2022]
Abstract
Immunisation of goats, mice, rats, rabbits, guinea pigs, and hamsters with the recombinant ectodomain of the porcine endogenous retrovirus (PERV) transmembrane envelope (TM) protein (p15E) induced binding and neutralising immune antibodies in all animals. In contrast, no antibodies were induced when pigs were immunised with p15E, indicating that pigs are tolerant to their endogenous retroviruses, at least to the TM protein. To answer the question of whether pigs are tolerant to other structural proteins of PERV, we immunised German landrace pigs with p15E, this time in conjunction with the surface envelope proteins gp70 and the core capsid Gag protein p27CA. To ensure that the pigs were immunocompetent and that immunisation was successful, all animals also received an injection of an unrelated protein, keyhole limpet hemocyanin (KLH). Whereas all animals produced antibodies against KLH, no animals produced antibodies against the viral envelope proteins, thus confirming previous results for p15E and extending them to the other envelope protein, gp70. However, the pigs did produce antibodies against p27CA, indicating that there is no tolerance to the core capsid protein of PERV.
Collapse
Affiliation(s)
- Joachim Denner
- Robert Koch Institute, HIV and Other Retroviruses, 13353 Berlin, Germany.
| | - Björn Petersen
- Friedrich Loeffler Institut, Institute of Farm Animal Genetics, Mariensee, 31535 Neustadt a.Rbge., Germany.
| | - Heiner Niemann
- Friedrich Loeffler Institut, Institute of Farm Animal Genetics, Mariensee, 31535 Neustadt a.Rbge., Germany.
| |
Collapse
|
32
|
Kimsa-Dudek M, Strzalka-Mrozik B, Kimsa MW, Blecharz I, Gola J, Skowronek B, Janiszewski A, Lipinski D, Zeyland J, Szalata M, Slomski R, Mazurek U. Screening pigs for xenotransplantation: expression of porcine endogenous retroviruses in transgenic pig skin. Transgenic Res 2015; 24:529-36. [PMID: 25812516 DOI: 10.1007/s11248-015-9871-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 03/23/2015] [Indexed: 01/30/2023]
Abstract
Pigs seem to be the answer to worldwide organ donor shortage. Porcine skin may also be applied as a dressing for severe burns. Genetic modifications of donor animals enable reduction of immune response, which prolongs xenograft survival as temporary biological dressing and allows achieving resistance against xenograft rejection. The risk posed by porcine endogenous retroviruses (PERVs) cannot be eliminated by breeding animals under specific-pathogen-free conditions and so all recipients of porcine graft will be exposed to PERVs. Therefore our study has been focused on the assessment of PERV DNA and mRNA level in skin samples of transgenic pigs generated for xenotransplantation. Porcine skin fragments were obtained from 3- to 6-month-old non-transgenic and transgenic Polish Landrace pigs. Transgenic pigs were produced by pronuclear DNA microinjection and were developed to express the human α-galactosidase and the human α-1,2-fucosyltransferase gene. The copy numbers of PERV DNA and RNA were evaluated using real-time Q-PCR and QRT-PCR. Comparative analysis of all PERV subtypes revealed that PERV-A is the main subtype of PERVs in analyzed skin samples. There was no significantly different copy number of PERV-A, PERV-B and PERV-C between non-transgenic pigs, pigs with the human α-galactosidase and pigs expressing the human α-1,2-fucosyltransferase gene, except of PERV-C DNA. It brings the conclusion, that transgenesis process exerts no influence on PERVs transinfection. That is another step forward in the development of pig skin xenografts as burn wounds dressing.
Collapse
Affiliation(s)
- Magdalena Kimsa-Dudek
- Department of Food and Nutrition, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Jednosci 8, 41-200, Sosnowiec, Poland,
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Zhu HT, Yu L, Lyu Y, Wang B. Optimal pig donor selection in islet xenotransplantation: current status and future perspectives. J Zhejiang Univ Sci B 2015; 15:681-91. [PMID: 25091986 DOI: 10.1631/jzus.b1400120] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Islet transplantation is an attractive treatment of type 1 diabetes mellitus. Xenotransplantation, using the pig as a donor, offers the possibility of an unlimited supply of islet grafts. Published studies demonstrated that pig islets could function in diabetic primates for a long time (>6 months). However, pig-islet xenotransplantation must overcome the selection of an optimal pig donor to obtain an adequate supply of islets with high-quality, to reduce xeno-antigenicity of islet and prolong xenograft survival, and to translate experimental findings into clinical application. This review discusses the suitable pig donor for islet xenotransplantation in terms of pig age, strain, structure/function of islet, and genetically modified pig.
Collapse
Affiliation(s)
- Hai-tao Zhu
- Department of Hepatobiliary Surgery, the First Affiliated Hospital, Medical College, Xi'an Jiaotong University, Xi'an 710061, China
| | | | | | | |
Collapse
|
34
|
Plotzki E, Wolf-van Buerck L, Knauf Y, Becker T, Maetz-Rensing K, Schuster M, Baehr A, Klymiuk N, Wolf E, Seissler J, Denner J. Virus safety of islet cell transplantation from transgenic pigs to marmosets. Virus Res 2015; 204:95-102. [PMID: 25956348 DOI: 10.1016/j.virusres.2015.04.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 04/15/2015] [Accepted: 04/16/2015] [Indexed: 12/16/2022]
Abstract
Transplantation of pig islet cells for the treatment of diabetes may be a more effective approach compared with the application of insulin. However, before introduction into the clinic, efficacy and safety of this treatment have to be shown. Non-human primate models may be used for this, despite the fact that they are characterised by several limitations. Here we investigate the prevalence of porcine endogenous retroviruses (PERVs), which are present in the genome of all pigs and which may infect human cells, as well as of porcine herpes viruses in donor pigs and their potential transmission to non-human primate recipients. Despite the fact that all three subtypes of PERV were present in all and porcine cytomegalovirus (PCMV) was found in some of the pigs, neither PERVs nor PCMV were found in the recipient animals under the experimental conditions applied. Porcine lymphotropic herpes viruses (PLHV) were not found in the donor pigs, hepatitis E virus (HEV) was not found in the recipients.
Collapse
Affiliation(s)
- Elena Plotzki
- Robert Koch Institute, HIV and Other Retroviruses, Nordufer 20, 13353 Berlin, Germany.
| | - Lelia Wolf-van Buerck
- Medizinische Klinik und Poliklinik IV, Diabeteszentrum, Ludwig-Maximilians-Universität, München, Ziemssenstraße 1, 80336 München, Germany.
| | - Yvonne Knauf
- German Primate Center, Leibniz-Institute, Pathology Unit, Kellnerweg 4, 37077 Göttingen, Germany.
| | - Tamara Becker
- German Primate Center, Leibniz-Institute, Pathology Unit, Kellnerweg 4, 37077 Göttingen, Germany.
| | - Kerstin Maetz-Rensing
- German Primate Center, Leibniz-Institute, Pathology Unit, Kellnerweg 4, 37077 Göttingen, Germany.
| | - Marion Schuster
- Medizinische Klinik und Poliklinik IV, Diabeteszentrum, Ludwig-Maximilians-Universität, München, Ziemssenstraße 1, 80336 München, Germany.
| | - Andrea Baehr
- Chair for Molecular Animal Breeding and Biotechnology and Laboratory for Functional Genome Analysis (LAFUGA), Gene Center, Ludwig-Maximilians-Universität München, Hackerstraße 27, 85764 Oberschleißheim, Germany.
| | - Nikolai Klymiuk
- Chair for Molecular Animal Breeding and Biotechnology and Laboratory for Functional Genome Analysis (LAFUGA), Gene Center, Ludwig-Maximilians-Universität München, Hackerstraße 27, 85764 Oberschleißheim, Germany.
| | - Eckhard Wolf
- Chair for Molecular Animal Breeding and Biotechnology and Laboratory for Functional Genome Analysis (LAFUGA), Gene Center, Ludwig-Maximilians-Universität München, Hackerstraße 27, 85764 Oberschleißheim, Germany.
| | - Jochen Seissler
- Medizinische Klinik und Poliklinik IV, Diabeteszentrum, Ludwig-Maximilians-Universität, München, Ziemssenstraße 1, 80336 München, Germany.
| | - Joachim Denner
- Robert Koch Institute, HIV and Other Retroviruses, Nordufer 20, 13353 Berlin, Germany.
| |
Collapse
|
35
|
Coelho AC, García Díez J. Biological Risks and Laboratory-Acquired Infections: A Reality That Cannot be Ignored in Health Biotechnology. Front Bioeng Biotechnol 2015; 3:56. [PMID: 25973418 PMCID: PMC4412124 DOI: 10.3389/fbioe.2015.00056] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 04/10/2015] [Indexed: 12/16/2022] Open
Abstract
Advances and research in biotechnology have applications over a wide range of areas, such as microbiology, medicine, the food industry, agriculture, genetically modified organisms, and nanotechnology, among others. However, research with pathogenic agents, such as virus, parasites, fungi, rickettsia, bacterial microorganisms, or genetic modified organisms, has generated concern because of their potential biological risk - not only for people, but also for the environment due to their unpredictable behavior. In addition, concern for biosafety is associated with the emergence of new diseases or re-emergence of diseases that were already under control. Biotechnology laboratories require biosafety measures designed to protect their staff, the population, and the environment, which may be exposed to hazardous organisms and materials. Laboratory staff training and education is essential, not only to acquire a good understanding about the direct handling of hazardous biological agents but also knowledge of the epidemiology, pathogenicity, and human susceptibility to the biological materials used in research. Biological risk can be reduced and controlled by the correct application of internationally recognized procedures such as proper microbiological techniques, proper containment apparatus, adequate facilities, protective barriers, and special training and education of laboratory workers. To avoid occupational infections, knowledge about standardized microbiological procedures and techniques and the use of containment devices, facilities, and protective barriers is necessary. Training and education about the epidemiology, pathogenicity, and biohazards of the microorganisms involved may prevent or decrease the risk. In this way, the scientific community may benefit from the lessons learned in the past to anticipate future problems.
Collapse
Affiliation(s)
- Ana Cláudia Coelho
- Department of Veterinary Sciences, Veterinary and Animal Science Center (CECAV), School of Agrarian and Veterinary Sciences, University of Trás-os-Montes e Alto Douro, Vila Real, Portugal
| | - Juan García Díez
- Department of Veterinary Sciences, Veterinary and Animal Science Center (CECAV), School of Agrarian and Veterinary Sciences, University of Trás-os-Montes e Alto Douro, Vila Real, Portugal
| |
Collapse
|
36
|
Semaan M, Ivanusic D, Denner J. Cytotoxic Effects during Knock Out of Multiple Porcine Endogenous Retrovirus (PERV) Sequences in the Pig Genome by Zinc Finger Nucleases (ZFN). PLoS One 2015; 10:e0122059. [PMID: 25909512 PMCID: PMC4409370 DOI: 10.1371/journal.pone.0122059] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 02/10/2015] [Indexed: 01/20/2023] Open
Abstract
Xenotransplantation has been proposed as a solution to the shortage of suitable human donors for transplantation and pigs are currently favoured as donor animals. However, xenotransplantation may be associated with the transmission of zoonotic microorganisms. Whereas most porcine microorganisms representing a risk for the human recipient may be eliminated by designated pathogen free breeding, multiple copies of porcine endogenous retroviruses (PERVs) are integrated in the genome of all pigs and cannot be eliminated this way. PERVs are released as infectious particles and infect human cells. The zinc finger nuclease (ZFN) technology allows knocking out specifically cellular genes, however it was not yet used to eliminate multiple integrated proviral sequences with a strong conservation in the target sequence. To reduce the risk of horizontal PERV transmission and to knock out as many as possible proviruses, for the first time the powerful tool of the ZFN technology was used. ZFN were designed to bind specifically to sequences conserved in all known replication-competent proviruses. Expression and transport of the ZFN into the nucleus was shown by Western blot analysis, co-localisation analysis, PLA and FRET. Survival of transfected cells was analysed using fluorescent ZFN and cell counting. After transfection a strong expression of the ZFN proteins and a co-localisation of the expressed ZFN proteins were shown. However, expression of the ZFN was found to be extremely toxic for the transfected cells. The induced cytotoxicity was likely due to the specific cutting of the high copy number of the PERV proviruses, which is also commonly observed when ZFN with low specificity cleave numerous off-target sites in a genome. This is the first attempt to knock out multiple, nearly identical, genes in a cellular genome using ZFN. The attempt failed, and other strategies should be used to prevent PERV transmission.
Collapse
Affiliation(s)
| | - Daniel Ivanusic
- Robert Koch Institute, Nordufer 20, Berlin, Germany
- Freie Universität Berlin, Kaiserswerther Str. 16–18, Berlin, Germany
| | - Joachim Denner
- Robert Koch Institute, Nordufer 20, Berlin, Germany
- * E-mail:
| |
Collapse
|
37
|
Shimode S, Nakagawa S, Miyazawa T. Multiple invasions of an infectious retrovirus in cat genomes. Sci Rep 2015; 5:8164. [PMID: 25641657 PMCID: PMC4313119 DOI: 10.1038/srep08164] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 01/07/2015] [Indexed: 01/08/2023] Open
Abstract
Endogenous retroviruses (ERVs) are remnants of ancient retroviral infections of host germ-line cells. While most ERVs are defective, some are active and express viral proteins. The RD-114 virus is a replication-competent feline ERV, and several feline cell lines produce infectious RD-114 viral particles. All domestic cats are considered to have an ERV locus encoding a replication-competent RD-114 virus in their genomes; however, the locus has not been identified. In this study, we investigated RD-114 virus-related proviral loci in genomes of domestic cats, and found that none were capable of producing infectious viruses. We also found that all domestic cats have an RD-114 virus-related sequence on chromosome C2, termed RDRS C2a, but populations of the other RDRSs are different depending on the regions where cats live or breed. Our results indicate that RDRS C2a, the oldest RD-114-related provirus, entered the host genome before an ancestor of domestic cats started diverging and the other new RDRSs might have integrated into migrating cats in Europe. We also show that infectious RD-114 virus can be resurrected by the recombination between two non-infectious RDRSs. From these data, we conclude that cats do not harbor infectious RD-114 viral loci in their genomes and RD-114-related viruses invaded cat genomes multiple times.
Collapse
Affiliation(s)
- Sayumi Shimode
- Laboratory of Signal Transduction, Department of Cell Biology, Institute for Virus Research, Kyoto University, 53 Shogoin-Kawaharacho, Sakyo-ku, Kyoto 606-8501, Japan
| | - So Nakagawa
- Department of Molecular Life Science, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan
| | - Takayuki Miyazawa
- Laboratory of Signal Transduction, Department of Cell Biology, Institute for Virus Research, Kyoto University, 53 Shogoin-Kawaharacho, Sakyo-ku, Kyoto 606-8501, Japan
| |
Collapse
|
38
|
Boksa M, Zeyland J, Słomski R, Lipiński D. Immune modulation in xenotransplantation. Arch Immunol Ther Exp (Warsz) 2014; 63:181-92. [PMID: 25354539 PMCID: PMC4429136 DOI: 10.1007/s00005-014-0317-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 07/22/2014] [Indexed: 01/17/2023]
Abstract
The use of animals as donors of tissues and organs for xenotransplantations may help in meeting the increasing demand for organs for human transplantations. Clinical studies indicate that the domestic pig best satisfies the criteria of organ suitability for xenotransplantation. However, the considerable phylogenetic distance between humans and the pig causes tremendous immunological problems after transplantation, thus genetic modifications need to be introduced to the porcine genome, with the aim of reducing xenotransplant immunogenicity. Advances in genetic engineering have facilitated the incorporation of human genes regulating the complement into the porcine genome, knockout of the gene encoding the formation of the Gal antigen (α1,3-galactosyltransferase) or modification of surface proteins in donor cells. The next step is two-fold. Firstly, to inhibit processes of cell-mediated xenograft rejection, involving natural killer cells and macrophages. Secondly, to inhibit rejection caused by the incompatibility of proteins participating in the regulation of the coagulation system, which leads to a disruption of the equilibrium in pro- and anti-coagulant activity. Only a simultaneous incorporation of several gene constructs will make it possible to produce multitransgenic animals whose organs, when transplanted to human recipients, would be resistant to hyperacute and delayed xenograft rejection.
Collapse
Affiliation(s)
- Magdalena Boksa
- Department of Biochemistry and Biotechnology, Poznań University of Life Sciences, Dojazd 11, 60-632, Poznań, Poland,
| | | | | | | |
Collapse
|
39
|
Keller M, Petersen B, Niemann H, Denner J. Lack of antibody response in pigs immunized with the transmembrane envelope protein of porcine endogenous retroviruses. J Gen Virol 2014; 95:1827-1831. [DOI: 10.1099/vir.0.064857-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recently, we immunized different mammalian species (goats, mice, rats, rabbits, guinea pigs and hamsters) with the recombinant ectodomain of the transmembrane envelope (TM) protein p15E of porcine endogenous retrovirus (PERV). In all cases, neutralizing immune sera were induced, which recognized epitopes in the fusion peptide proximal region and the membrane proximal external region of p15E. In order to analyse whether pigs are also able to produce such antibodies, and whether such antibodies can be used to study the involvement of the TM protein in placental development (as was shown for endogenous retroviruses of other species), German landrace pigs were immunized with PERV p15E. No binding and neutralizing antibodies were produced as shown in three Western blot analyses and in a neutralization assay, indicating that pigs are tolerant to their endogenous retroviruses, at least for the ectodomain of the TM protein.
Collapse
Affiliation(s)
- Martina Keller
- Robert Koch Institute, HIV and Other Retroviruses, 13353 Berlin, Germany
| | - Björn Petersen
- Friedrich Loeffler Institute, Federal Research Institute for Animal Health, Institute of Farm Animal Genetics, Department of Biotechnology, 31535 Neustadt am Rübenberge, Germany
| | - Heiner Niemann
- Friedrich Loeffler Institute, Federal Research Institute for Animal Health, Institute of Farm Animal Genetics, Department of Biotechnology, 31535 Neustadt am Rübenberge, Germany
| | - Joachim Denner
- Robert Koch Institute, HIV and Other Retroviruses, 13353 Berlin, Germany
| |
Collapse
|
40
|
Jung WY, Yu SL, Seo DW, Jung KC, Cho IC, Lim HT, Jin DI, Lee JH. Characterization of insertional variation of porcine endogenous retroviruses in six different pig breeds. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2014; 25:1357-63. [PMID: 25049490 PMCID: PMC4093020 DOI: 10.5713/ajas.2012.12131] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Revised: 07/11/2012] [Accepted: 05/01/2012] [Indexed: 11/27/2022]
Abstract
Pigs may need to be exploited as xenotransplantation donors due to the shortage of human organs, tissues and cells. Porcine endogenous retroviruses (PERVs) are a significant obstacle to xenotransplantation because they can infect human cells in vitro and have the potential for transmission of unexpected pathogens to humans. In this research, 101 pigs, including four commercial breeds (23 Berkshire, 13 Duroc, 22 Landrace and 14 Yorkshire pigs), one native breed (19 Korean native pigs) and one miniature breed (10 NIH miniature pigs) were used to investigate insertional variations for 11 PERV loci (three PERV-A, six PERV-B and two PERV-C). Over 60% of the pigs harbored one PERV-A (907F8) integration and five PERV-B (B3-3G, B3-7G, 742H1, 1155D9 and 465D1) integrations. However, two PERV-A loci (A1-6C and 1347C1) and one PERV-B locus (B3-7F) were absent in Duroc pigs. Moreover, two PERV-C loci (C2-6C and C4-2G) only existed in Korean native pigs and NIH miniature pigs. The results suggest that PERV insertional variations differ among pig breeds as well as among individuals within a breed. Also, the results presented here can be used for the selection of animals that do not have specific PERV integration for xenotransplantation research.
Collapse
Affiliation(s)
- W Y Jung
- National Agricultural Products Quality Management Service, Gyungki 430-824, Korea
| | - S L Yu
- National Agricultural Products Quality Management Service, Gyungki 430-824, Korea
| | - D W Seo
- National Agricultural Products Quality Management Service, Gyungki 430-824, Korea
| | - K C Jung
- National Agricultural Products Quality Management Service, Gyungki 430-824, Korea
| | - I C Cho
- National Institute of Animal Science, Jeju 690-150, Korea
| | - H T Lim
- Division of Applied Life Science, Gyeongsang National University, Jinju 660-701, Korea
| | - D I Jin
- National Agricultural Products Quality Management Service, Gyungki 430-824, Korea
| | - J H Lee
- National Agricultural Products Quality Management Service, Gyungki 430-824, Korea
| |
Collapse
|
41
|
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.
Collapse
|
42
|
Jung YD, Lee JR, Kim YJ, Ha HS, Oh KB, Im GS, Choi BH, Kim HS. Promoter activity analysis and methylation characterization of LTR elements of PERVs in NIH miniature pig. Genes Genet Syst 2014; 88:135-42. [PMID: 23832305 DOI: 10.1266/ggs.88.135] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The potential risk of porcine endogenous retrovirus (PERV) transmission is an important issue in xenotransplantation (pig-to-human transplantation). Long terminal repeats (LTRs) in PERV elements show promoter activity that could affect neighboring functional genes. The methylation status and promoter activities of 3 LTR structures (PERV-LTR1, LTR2, and LTR3 elements) belonging to the PERV-A family were examined using luciferase reporter genes in human liver cell lines (HepG2 and Hep3B). The PERV LTR3 element exhibited hypomethylation and stronger promoter activity than the other LTR elements in human liver cells. We also performed comparative sequences analysis of the PERV LTR elements by using bioinformatics tools. Our findings showed that several transcription factors such as Nkx2-2 and Elk-1 positively influenced the high transcriptional activity of the PERV LTR3 element.
Collapse
Affiliation(s)
- Yi-Deun Jung
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea
| | | | | | | | | | | | | | | |
Collapse
|
43
|
Li ZG, Liu GB, Pan MX, Wu QS, Ge M, Du J, Wang Y, Gao Y. Knockdown of porcine endogenous retroviruses by RNA interference in Chinese experimental miniature pig fibroblasts. Transplant Proc 2013; 45:748-55. [PMID: 23498816 DOI: 10.1016/j.transproceed.2012.03.068] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 01/30/2012] [Accepted: 03/06/2012] [Indexed: 11/27/2022]
Abstract
BACKGROUND The clinical application of porcine-derived xenotransplants is limited by the potential risk of infection due to the presence of porcine endogenous retrovirus (PERV) in tissues, organs, and cells. The establishment of pig fibroblasts with low PERV expression and without PERV-C can provide a nuclear donor to generate a safer transgenic pig. METHODS In this study, we obtained Chinese Experimental Miniature Pig fibroblasts (CEMPF) with low expression of PERV and none of PERV-C. We designed small interfering RNA (siRNA) expressed as short hairpin RNAs (shRNA) based on the highly conserved gag and pol regions of PERV and screened for the most effective siRNA to inhibit PERV expression. The selected shRNA-pol3 fragment was introduced into the CEMPF to obtain an engineered CEMPF stably expressing shRNA-pol3. RESULTS The PERV mRNA expression level in the engineered CEMPF was only 7.9% of that observed in fibroblasts from wild-type CEMPF, PERV P15E protein expression was significantly reduced. HEK293 cells cocultured with the supernate of the engineered CEMPF showed no PERV infection. CONCLUSIONS Engineered CEMPF, which possess no risk of PERV-A/C infection, can serve as a nuclear donor to generate xenograft donor pigs.
Collapse
Affiliation(s)
- Z-G Li
- Department of Hepatobiliary Surgery, Zhujiang Hospital, Guangzhou, PR China
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Lin X, Qi L, Li Z, Chi H, Lin W, Wang Y, Jiang Z, Pan M, Gao Y. Susceptibility of human liver cells to porcine endogenous retrovirus. EXP CLIN TRANSPLANT 2013; 11:541-5. [PMID: 23901808 DOI: 10.6002/ect.2012.0213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVES The risk of porcine endogenous retrovirus infection is a major barrier for pig-to-human xenotransplant. Porcine endogenous retrovirus, present in porcine cells, can infect many human and nonhuman primate cells in vitro, but there is no evidence available about in vitro infection of human liver cells. We investigated the susceptibility of different human liver cells to porcine endogenous retrovirus. MATERIALS AND METHODS The supernatant from a porcine kidney cell line was added to human liver cells, including a normal hepatocyte cell line (HL-7702 cells), primary hepatocytes (Phh cells), and a liver stellate cell line (Lx-2 cells), and to human embryonic kidney cells as a reference control. Expression of the porcine endogenous retrovirus antigen p15E in the human cells was evaluated with polymerase chain reaction, reverse transcription-polymerase chain reaction, and Western blot. RESULTS The porcine endogenous retrovirus antigen p15E was not expressed in any human liver cells (HL-7702, Phh, or Lx-2 cells) that had been exposed to supernatants from porcine kidney cell lines. Porcine endogenous retrovirus-specific fragments were amplified in human kidney cells. CONCLUSIONS Human liver cells tested were not susceptible to infection by porcine endogenous retrovirus. Therefore, not all human cells are susceptible to porcine endogenous retrovirus.
Collapse
Affiliation(s)
- Xinzi Lin
- Department of Hepatobiliary Surgery, Zhujiang Hospital, China
| | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Semaan M, Rotem A, Barkai U, Bornstein S, Denner J. Screening pigs for xenotransplantation: prevalence and expression of porcine endogenous retroviruses in Göttingen minipigs. Xenotransplantation 2013; 20:148-56. [DOI: 10.1111/xen.12032] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 03/12/2013] [Indexed: 12/01/2022]
Affiliation(s)
- Marwan Semaan
- Robert Koch Institute; HIV and Other Retroviruses; Berlin Germany
| | - Avi Rotem
- Beta-O 2 Technologies Ltd; Petach-Tikva Israel
| | | | - Stefan Bornstein
- Center Internal Medicine; University Clinics Carl Gustav Carus; Technical University; Dresden Germany
| | - Joachim Denner
- Robert Koch Institute; HIV and Other Retroviruses; Berlin Germany
| |
Collapse
|
46
|
Jung YD, Ha HS, Park SJ, Oh KB, Im GS, Kim TH, Seong HH, Kim HS. Identification and promoter analysis of PERV LTR subtypes in NIH-miniature pig. Mol Cells 2013; 35:99-105. [PMID: 23456331 PMCID: PMC3887905 DOI: 10.1007/s10059-013-2289-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Revised: 11/20/2012] [Accepted: 12/11/2012] [Indexed: 11/28/2022] Open
Abstract
Porcine endogenous retroviruses (PERVs) are integrated into the genomes of all pigs. Since some PERVs can also infect human cells, they represent a potential risk for xenotransplantation involving pig cells or organs. The long terminal repeat (LTR) elements of PERVs show promoter activity that can affect human functional genes; therefore, we examined these elements in this study. We detected several expressed LTRs in the NIH-miniature pig liver, among which we identified 9 different subtypes. When these LTRs were compared, distinct structures that contained several insertion and deletion (INDEL) events and tandem repeats were identified in the U3 region. The transcriptional activity of the 9 LTR subtypes was analyzed in the PK15 porcine cell line and in the HepG2 and Hep3B human liver cell lines, and transcriptional regulation was found to be different in the 3 cell lines. The D LTR subtype was found to have stronger promoter activity than all other types in 4 different human cell lines (HepG2, Hep3B, U251, and 293). Using computational approaches, the D type was shown to contain 4 transcription factor-binding sites distinct from those in the U3 regions of the other subtypes. Therefore, deletion mutants were constructed and examined by a transient transfection luciferase assay. The results of this analysis indicated that the binding site for the Hand1:E47 transcription factor might play a positive role in the transcriptional regulation of PERV LTR subtype D in human liver cell lines.
Collapse
Affiliation(s)
- Yi-Deun Jung
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735,
Korea
| | | | - Sang-Je Park
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735,
Korea
| | | | | | | | | | - Heui-Soo Kim
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735,
Korea
| |
Collapse
|
47
|
|
48
|
Bittmann I, Mihica D, Plesker R, Denner J. Expression of porcine endogenous retroviruses (PERV) in different organs of a pig. Virology 2012; 433:329-36. [DOI: 10.1016/j.virol.2012.08.030] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 06/21/2012] [Accepted: 08/18/2012] [Indexed: 10/27/2022]
|
49
|
Kaulitz D, Mihica D, Adlhoch C, Semaan M, Denner J. Improved pig donor screening including newly identified variants of porcine endogenous retrovirus-C (PERV-C). Arch Virol 2012; 158:341-8. [PMID: 23053520 DOI: 10.1007/s00705-012-1490-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 08/16/2012] [Indexed: 11/30/2022]
Abstract
Porcine endogenous retroviruses (PERV) are widely distributed in the genomes of pigs. PERV-A and PERV-B are present in all pigs. They infect human cells in vitro and therefore represent a risk for xenotransplantation when pig cells, tissues or organs are used. PERV-C infects only pig cells and is not present in the genomes of all pigs. However, PERV-A/C recombinants infecting human cells and characterized by high replication titers were found in pigs. To select PERV-C-free animals that cannot generate such recombinants, PCR-based assays were developed (Kaulitz et al., J Virol Methods, 175:60, 2011). When screening for PERV-C in German wild boars (Sus scrofa scrofa), applying these methods, a new variant of PERV-C was identified. Whereas in all 125 wild boar only the new variant of PERV-C was found, different variants were present in some landrace pigs, and most importantly, some pigs were totally free of PERV-C.
Collapse
Affiliation(s)
- Danny Kaulitz
- Centre of HIV and Retrovirology, Robert Koch-Institute, Nordufer 20, 13353, Berlin, Germany
| | | | | | | | | |
Collapse
|
50
|
Nakaya Y, Shimode S, Kobayashi T, Imakawa K, Miyazawa T. Binding of transcription factor activating protein 2 γ on the 5'-proximal promoter region of human porcine endogenous retrovirus subgroup A receptor 2/GPR172B. Xenotransplantation 2012; 19:177-85. [PMID: 22702469 DOI: 10.1111/j.1399-3089.2012.00701.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Xenotransplantation is one of the solutions for the shortage of organ donors, and pigs have been considered to be the most suitable animal donors. Specific pathogen-free pigs are utilized in the xenotransplantation; however, pigs have infectious gammaretroviruses, named porcine endogenous retroviruses (PERVs) in their genome. Of them, PERV-A and PERV-B can infect human cells in vitro and potentially induce diseases like other gammaretroviruses. The human cellular receptors for PERV-A were identified and named human PERV-A receptor (HuPAR)-1 and HuPAR-2 (also called as GPR172A and GPR172B, respectively). We have recently reported that HuPAR-2 expression was regulated by epigenetic modification and preferentially expressed in placenta. However, the detailed mechanisms of HuPAR-2 expression have not been fully characterized. In this study, we analyzed molecular mechanisms associated with HuPAR-2 transcription through the identification of transcription factors that bind to the promoter region of HuPAR-2. METHODS In situ hybridization was performed to identify the cells expressing HuPAR-2 in placental tissues. Transcriptional activities were measured by dual-luciferase reporter assay using serial deletion mutants of HuPAR-2 5'-flanking region. To identify the transcription factors bound to the promoter region, in silico analysis, electrophoresis mobility shift assay, and chromatin immunoprecipitation assay were conducted. The effect of the transcription factor transcription factor activator protein (TFAP)-2γ on the promoter activities was investigated by overexpression of the factor. RESULTS We identified that HuPAR-2 was specifically expressed in villous trophoblast cells. We also identified that a region spanning from -126 to -32 had proximal promoter activities and TFAP-2γ bound to a region spanning from -58 to -35 in vitro and in vivo. The overexpression of TFAP-2γ also augmented the proximal promoter activity. CONCLUSION We demonstrated that TFAP-2γ is one of the transcription factors involved in the HuPAR-2 expression in human villous trophoblast cells. By studying transcriptional factors involved in the expression of HuPAR-2, we may find a clue to control the potential risks caused by PERV-A infection in xenotransplantation.
Collapse
Affiliation(s)
- Yuki Nakaya
- Laboratory of Signal Transduction, Department of Cell Biology, Institute for Virus Research, Kyoto University, Sakyo-ku, Kyoto, Japan
| | | | | | | | | |
Collapse
|