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Li X, Wang Y, Yang H, Dai Y. Liver and Hepatocyte Transplantation: What Can Pigs Contribute? Front Immunol 2022; 12:802692. [PMID: 35095885 PMCID: PMC8795512 DOI: 10.3389/fimmu.2021.802692] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/30/2021] [Indexed: 12/25/2022] Open
Abstract
About one-fifth of the population suffers from liver diseases in China, meaning that liver disorders are prominent causative factors relating to the Chinese mortality rate. For patients with end-stage liver diseases such as hepatocellular carcinoma or acute liver diseases with life-threatening liver dysfunction, allogeneic liver transplantation is the only life-saving treatment. Hepatocyte transplantation is a promising alternative for patients with acute liver failure or those considered high risk for major surgery, particularly for the bridge-to-transplant period. However, the lack of donors has become a serious global problem. The clinical application of porcine xenogeneic livers and hepatocytes remains a potential solution to alleviate the donor shortage. Pig grafts of xenotransplantation play roles in providing liver support in recipients, together with the occurrence of rejection, thrombocytopenia, and blood coagulation dysfunction. In this review, we present an overview of the development, potential therapeutic impact, and remaining barriers in the clinical application of pig liver and hepatocyte xenotransplantation to humans and non-human primates. Donor pigs with optimized genetic modification combinations and highly effective immunosuppressive regimens should be further explored to improve the outcomes of xenogeneic liver and hepatocyte transplantation.
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Affiliation(s)
- Xiaoxue Li
- Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Nanjing, China
| | - Ying Wang
- Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Nanjing, China.,Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Nanjing Medical University, Nanjing, China
| | - Haiyuan Yang
- Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Nanjing, China.,Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Nanjing Medical University, Nanjing, China
| | - Yifan Dai
- Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Nanjing, China.,Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Nanjing Medical University, Nanjing, China.,State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China.,Shenzhen Xenotransplantation Medical Engineering Research and Development Center, Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen, China
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Zhang G, Iwase H, Li Q, Yamamoto T, Jagdale A, Ezzelarab MB, Ayares D, Cooper DKC, Hara H, Wang G. The Role of Interleukin-6 (IL-6) in the Systemic Inflammatory Response in Xenograft Recipients and in Pig Kidney Xenograft Failure. Front Immunol 2021; 12:788949. [PMID: 34956220 PMCID: PMC8692283 DOI: 10.3389/fimmu.2021.788949] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 11/18/2021] [Indexed: 11/20/2022] Open
Abstract
Background In pig-to-baboon transplantation models, there is increasing evidence of systemic inflammation in xenograft recipients (SIXR) associated with pig xenograft failure. We evaluated the relationship between systemic inflammatory factors and pig kidney xenograft failure. Methods Baboons received kidney transplants from genetically engineered pigs (n=9), and received an anti-CD40mAb-based (n=4) or conventional (n=5) immunosuppressive regimen. The pig kidney grafts were monitored by measurements of serum creatinine, serum amyloid A (SAA), white blood cell (WBC) and platelet counts, plasma fibrinogen, and pro-inflammatory cytokines (baboon and pig IL-6, TNF-α, IL-1β). Results Six baboons were euthanized or died from rejection, and 3 were euthanized for infection. Changes in serum creatinine correlated with those of SAA (r=0.56, p<0.01). Serum baboon IL-6 was increased significantly on day 1 after transplantation and at euthanasia (both p<0.05) and correlated with serum creatinine and SAA (r=0.59, p<0.001, r=0.58, p<0.01; respectively). but no difference was observed between rejection and infection. Levels of serum pig IL-6, TNF-α, IL-1β were also significantly increased on day 1 and at euthanasia, and serum pig IL-6 and IL-1β correlated with serum creatinine and SAA. The level of serum baboon IL-6 correlated with the expression of IL-6 and amyloid A in the baboon liver (r=0.93, p<0.01, r=0.79, p<0.05; respectively). Conclusion Early upregulation of SAA and serum IL-6 may indicate the development of rejection or infection, and are associated with impaired kidney graft function. Detection and prevention of systemic inflammation may be required to prevent pig kidney xenograft failure after xenotransplantation.
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Affiliation(s)
- Guoqiang Zhang
- Department of General Surgery, Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, China.,Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Hayato Iwase
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Qi Li
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Takayuki Yamamoto
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Abhijit Jagdale
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Mohamed B Ezzelarab
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, United States
| | | | - David K C Cooper
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Boston, MA, United States
| | - Hidetaka Hara
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Gangcheng Wang
- Department of General Surgery, Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, China
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Alberio R, Wolf E. 25th ANNIVERSARY OF CLONING BY SOMATIC-CELL NUCLEAR TRANSFER: Nuclear transfer and the development of genetically modified/gene edited livestock. Reproduction 2021; 162:F59-F68. [PMID: 34096507 PMCID: PMC8240728 DOI: 10.1530/rep-21-0078] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 05/04/2021] [Indexed: 12/11/2022]
Abstract
The birth and adult development of 'Dolly' the sheep, the first mammal produced by the transfer of a terminally differentiated cell nucleus into an egg, provided unequivocal evidence of nuclear equivalence among somatic cells. This ground-breaking experiment challenged a long-standing dogma of irreversible cellular differentiation that prevailed for over a century and enabled the development of methodologies for reversal of differentiation of somatic cells, also known as nuclear reprogramming. Thanks to this new paradigm, novel alternatives for regenerative medicine in humans, improved animal breeding in domestic animals and approaches to species conservation through reproductive methodologies have emerged. Combined with the incorporation of new tools for genetic modification, these novel techniques promise to (i) transform and accelerate our understanding of genetic diseases and the development of targeted therapies through creation of tailored animal models, (ii) provide safe animal cells, tissues and organs for xenotransplantation, (iii) contribute to the preservation of endangered species, and (iv) improve global food security whilst reducing the environmental impact of animal production. This review discusses recent advances that build on the conceptual legacy of nuclear transfer and – when combined with gene editing – will have transformative potential for medicine, biodiversity and sustainable agriculture. We conclude that the potential of these technologies depends on further fundamental and translational research directed at improving the efficiency and safety of these methods.
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Affiliation(s)
- Ramiro Alberio
- School of Biosciences University of Nottingham, Nottingham, UK
| | - Eckhard Wolf
- Gene Center and Department of Veterinary Sciences, LMU Munich, Munich, Germany
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Anti-pig IgE and IgA Antibodies in Naive Primates and Nonhuman Primates With Pig Xenografts. Transplantation 2021; 105:318-327. [PMID: 32796494 DOI: 10.1097/tp.0000000000003408] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND Natural preformed anti-pig IgM/IgG antibodies in primates play an important role in xenograft rejection. As it is not clear how IgE and IgA engage in the immune system in xenotransplantation, we investigated natural preformed and elicited anti-pig IgE/IgA in naive primates and after xenotransplantation in nonhuman primates. METHODS The binding of IgM/IgG/IgE/IgA antibodies to red blood cells (RBCs) from wild-type (WT), α1,3-galactosyltransferase gene-knockout (GTKO), and GTKO/cytidine monophospho-N-acetylneuraminic acid hydroxylase gene-knockout/β-1,4 N-acetylgalactosaminyltransferase 2 gene-knockout (ie, triple-knockout pigs) pigs were measured by flow cytometry in naive human (n = 50) and baboon (n = 14) sera. Antibody binding to WT and GTKO pig RBCs (pRBCs) was also measured in the sera of baboons (nonsensitized n = 7, sensitized n = 2) and rhesus monkeys (nonsensitized n = 2, sensitized n = 11) following WT or GTKO pig organ/tissue xenotransplantation. Deposition of IgM/IgG/IgE/IgA in the grafts was detected by immunohistochemistry. RESULTS The majority of humans had natural preformed IgM/IgG/IgE/IgA to WT and GTKO pRBCs. In contrast, IgM/IgG/IgE/IgA to triple-knockout pRBCs were present at lower levels and frequency (P < 0.01). Baboons also had IgM/IgG/IgE/IgA antibodies against WT pRBCs, but fewer to GTKO and triple-knockout (P < 0.01). After xenotransplantation into nonhuman primates, when IgM/IgG increased, IgE/IgA also increased, but to a lesser extent. In addition to IgM/IgG, IgE or IgA deposition was observed in rejected pig xenografts. CONCLUSIONS Primates develop serum anti-pig IgE/IgA antibodies both naturally and during xenograft rejection. The pathophysiological role, if any, of anti-pig IgE/IgA antibodies remains unknown.
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Ren J, Yu D, Fu R, An P, Sun R, Wang Z, Guo R, Li H, Zhang Y, Li Z, Yang YG, Li W, Hai T, Hu Z. IL2RG-deficient minipigs generated via CRISPR/Cas9 technology support the growth of human melanoma-derived tumours. Cell Prolif 2020; 53:e12863. [PMID: 32871045 PMCID: PMC7574875 DOI: 10.1111/cpr.12863] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 05/21/2020] [Accepted: 06/03/2020] [Indexed: 01/05/2023] Open
Abstract
Objectives Immunodeficient mice injected with human cancer cell lines have been used for human oncology studies and anti‐cancer drug trials for several decades. However, rodents are not ideal species for modelling human cancer because rodents are physiologically dissimilar to humans. Therefore, anti‐tumour drugs tested effective in rodents have a failure rate of 90% or higher in phase III clinical trials. Pigs are similar to humans in size, anatomy, physiology and drug metabolism rate, rendering them a desirable pre‐clinical animal model for assessing anti‐cancer drugs. However, xenogeneic immune rejection is a major barrier to the use of pigs as hosts for human tumours. Interleukin (IL)‐2 receptor γ (IL2RG), a common signalling subunit for multiple immune cytokines including IL‐2, IL‐4, IL‐7, IL‐9, IL‐15 and IL‐21, is required for proper lymphoid development. Materials and Methods IL2RG−/Y pigs were generated by CRISPR/Cas9 technology, and examined for immunodeficiency and ability to support human oncogenesis. Results Compared to age‐matched wild‐type pigs, IL2RG−/Y pigs exhibited a severely impaired immune system as shown by lymphopenia, lymphoid organ atrophy, poor immunoglobulin function, and T‐ and NK‐cell deficiency. Human melanoma Mel888 cells generated tumours in IL2RG−/Y pigs but not in wild‐type littermates. The human tumours grew faster in IL2RG−/Y pigs than in nude mice. Conclusions Our results indicate that these pigs are promising hosts for modelling human cancer in vivo, which may aid in the discovery and development of anti‐cancer drugs.
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Affiliation(s)
- Jilong Ren
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Dawei Yu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
| | - Rui Fu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
| | - Peipei An
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital, Jilin University, Changchun, China
| | - Renren Sun
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital, Jilin University, Changchun, China
| | - Zhengzhu Wang
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital, Jilin University, Changchun, China
| | - Runfa Guo
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
| | - Haoyun Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
| | - Ying Zhang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
| | - Ziyi Li
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital, Jilin University, Changchun, China
| | - Yong-Guang Yang
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital, Jilin University, Changchun, China
| | - Wei Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Tang Hai
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
| | - Zheng Hu
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital, Jilin University, Changchun, China
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Singh AK, Chan JL, DiChiacchio L, Hardy NL, Corcoran PC, Lewis BGT, Thomas ML, Burke AP, Ayares D, Horvath KA, Mohiuddin MM. Cardiac xenografts show reduced survival in the absence of transgenic human thrombomodulin expression in donor pigs. Xenotransplantation 2018; 26:e12465. [PMID: 30290025 DOI: 10.1111/xen.12465] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 07/20/2018] [Accepted: 09/10/2018] [Indexed: 12/13/2022]
Abstract
A combination of genetic manipulations of donor organs and target-specific immunosuppression is instrumental in achieving long-term cardiac xenograft survival. Recently, results from our preclinical pig-to-baboon heterotopic cardiac xenotransplantation model suggest that a three-pronged approach is successful in extending xenograft survival: (a) α-1,3-galactosyl transferase (Gal) gene knockout in donor pigs (GTKO) to prevent Gal-specific antibody-mediated rejection; (b) transgenic expression of human complement regulatory proteins (hCRP; hCD46) and human thromboregulatory protein thrombomodulin (hTBM) to avoid complement activation and coagulation dysregulation; and (c) effective induction and maintenance of immunomodulation, particularly through co-stimulation blockade of CD40-CD40L pathways with anti-CD40 (2C10R4) monoclonal antibody (mAb). Using this combination of manipulations, we reported significant improvement in cardiac xenograft survival. In this study, we are reporting the survival of cardiac xenotransplantation recipients (n = 3) receiving xenografts from pigs without the expression of hTBM (GTKO.CD46). We observed that all grafts underwent rejection at an early time point (median 70 days) despite utilization of our previously reported successful immunosuppression regimen and effective control of non-Gal antibody response. These results support our hypothesis that transgenic expression of human thrombomodulin in donor pigs confers an independent protective effect for xenograft survival in the setting of a co-stimulation blockade-based immunomodulatory regimen.
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Affiliation(s)
- Avneesh K Singh
- Cardiothoracic Surgery Research Program/National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland.,Department of Surgery, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Joshua L Chan
- Cardiothoracic Surgery Research Program/National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Laura DiChiacchio
- Department of Surgery, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Naomi L Hardy
- Department of Pathology at the University of Maryland Medical Center, University of Maryland, Baltimore, Maryland
| | - Philip C Corcoran
- Cardiothoracic Surgery Research Program/National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Billeta G T Lewis
- Division of Veterinary Resources, Office of Research Services, National Institutes of Health, Bethesda, Maryland
| | - Marvin L Thomas
- Division of Veterinary Resources, Office of Research Services, National Institutes of Health, Bethesda, Maryland
| | - Allen P Burke
- Department of Pathology at the University of Maryland Medical Center, University of Maryland, Baltimore, Maryland
| | | | - Keith A Horvath
- Cardiothoracic Surgery Research Program/National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Muhammad M Mohiuddin
- Cardiothoracic Surgery Research Program/National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland.,Department of Surgery, School of Medicine, University of Maryland, Baltimore, Maryland
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Li T, Hara H, Ezzelarab MB, Long C, Long Y, Wang Y, Cooper DKC, Iwase H. Serum amyloid A as a marker of inflammation in xenotransplantation. EUR J INFLAMM 2018. [DOI: 10.1177/2058739218780046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Increasing evidence indicates that inflammation plays a role in pig-to-baboon organ xenotransplantation. We have evaluated serum amyloid A (SAA) as a marker of inflammation in baboons with various pig xenografts. We measured SAA levels in recipient baboons with pig artery patch (n = 5), life-supporting kidney (n = 5), heterotopic heart (n = 2), or hepatocyte (n = 1) grafts and using an OmniChek-SAA for Inflammation & Infection kit. C-reactive protein (CRP), another marker of inflammation (e.g. D-dimer), was also measured.SAA indicated increased inflammation when baboons developed consumptive coagulopathy (CC; e.g. thrombocytopenia) or infection. SAA also indicated that treatment of the recipient with tocilizumab reduced inflammation. There was significant positive correlation between SAA with changes in CRP (r = 0.6, P < 0.05) and with D-dimer (r = 0.8, P < 0.01), but SAA appeared at times to more accurately reflect the clinical state of the baboon. In sum, measurement of SAA proved simple and quick, and indicated (1) significant inflammation when CC or infection was present, and (2) reduced inflammation when treatment with tocilizumab was administered.
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Affiliation(s)
- Tao Li
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
- Center for Kidney Transplantation, Second Affiliated Hospital of the University of South China, Hengyang, Hunan, China
- ZhuZhou Central Hosptial, ZhuZhou, Hunan, China
| | - Hidetaka Hara
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Mohamed B Ezzelarab
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Cassandra Long
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Yongqi Long
- ZhuZhou Central Hosptial, ZhuZhou, Hunan, China
| | - Yi Wang
- Center for Kidney Transplantation, Second Affiliated Hospital of the University of South China, Hengyang, Hunan, China
| | - David KC Cooper
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Hayato Iwase
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
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Abstract
PURPOSE OF REVIEW To review the progress in the field of xenotransplantation with special attention to most recent encouraging findings which will eventually bring xenotransplantation to the clinic in the near future. RECENT FINDINGS Starting from early 2000, with the introduction of galactose-α1,3-galactose (Gal)-knockout pigs, prolonged survival especially in heart and kidney xenotransplantation was recorded. However, remaining antibody barriers to non-Gal antigens continue to be the hurdle to overcome. The production of genetically engineered pigs was difficult requiring prolonged time. However, advances in gene editing, such as zinc finger nucleases, transcription activator-like effector nucleases, and most recently clustered regularly interspaced short palindromic repeats (CRISPR) technology made the production of genetically engineered pigs easier and available to more researchers. Today, the survival of pig-to-nonhuman primate heterotopic heart, kidney, and islet xenotransplantation reached more than 900, more than 400, and more than 600 days, respectively. The availability of multiple-gene pigs (five or six genetic modifications) and/or newer costimulation blockade agents significantly contributed to this success. Now, the field is getting ready for clinical trials with an international consensus. SUMMARY Clinical trials in cellular or solid organ xenotransplantation are getting closer with convincing preclinical data from many centers. The next decade will show us new achievements and additional barriers in clinical xenotransplantation.
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Cimeno A, French BM, Powell JM, Phelps C, Ayares D, O'Neill NA, Laird CT, Pierson RN, Azimzadeh AM, Barth RN, LaMattina JC. Synthetic liver function is detectable in transgenic porcine livers perfused with human blood. Xenotransplantation 2017; 25. [PMID: 29067741 DOI: 10.1111/xen.12361] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 09/21/2017] [Accepted: 09/26/2017] [Indexed: 12/27/2022]
Abstract
In addition to immune barriers, molecular incompatibilities between species are predicted to limit pig liver survival in primate xenotransplantation models. Assessment and measurement of synthetic function of genetically modified porcine livers after ex vivo perfusion with human blood have not previously been described. Eight porcine livers from α1,3-galactosyl transferase knockout and human membrane cofactor (GalTKO.hCD46), six livers from GalTKO.hCD46 and N-glycolylneuraminic acid knockout (GalTKO.hCD46.Neu5GcKO), and six livers from GalTKO.hCD46 with humanized decay-accelerating factor (hCD55), endothelial protein C receptor (hEPCR), tissue factor pathway inhibitor (hTFPI), and integrin-associated protein (hCD47) (GalTKO.hCD46.hCD55.hEPCR.hTFPI.hCD47) pigs were perfused with human blood under physiologic conditions. Timed blood samples were tested for liver enzymes and for pig-specific albumin production via Western blot. Porcine albumin levels increased with time in all experiments. By densitometry, GalTKO.hCD46.Neu5GcKO livers had the highest albumin levels, measured both as total produced, and when controlled for perfusion duration, compared to GalTKO.hCD46 (P = .068) and GalTKO.hCD46.hCD55.hEPCR.hTFPI.hCD47 livers (P = .04). Porcine livers perfused with human blood demonstrated the synthetic ability to produce albumin in all cases. GalTKO.hCD46.Neu5GcKO pig livers demonstrated the most robust albumin production. This suggests that the Neu5GcKO phenotype provides a protective effect on the graft due to decreased human antibody recognition and graft injury.
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Affiliation(s)
- Arielle Cimeno
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Beth M French
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Jessica M Powell
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | | | | | - Natalie A O'Neill
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Christopher T Laird
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Richard N Pierson
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Agnes M Azimzadeh
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Rolf N Barth
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - John C LaMattina
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
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Potential Antigens Involved in Delayed Xenograft Rejection in a Ggta1/Cmah Dko Pig-to-Monkey Model. Sci Rep 2017; 7:10024. [PMID: 28855711 PMCID: PMC5577312 DOI: 10.1038/s41598-017-10805-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 08/15/2017] [Indexed: 12/25/2022] Open
Abstract
When hyperacute rejection is avoided by deletion of Gal expression in the pig, delayed xenograft rejection (DXR) becomes a major immunologic barrier to successful xenotransplantation. This study was to investigate the potential antigens involved in DXR. We isolated primary renal microvascular endothelial cells (RMEC) and aortic endothelial cells (AEC) from a GGTA1/CMAH double-knockout (DKO) pig (and a GGTA1-KO pig) and immunized cynomolgus monkeys with both of these cells. After sensitization, monkey serum antibody binding and cytotoxicity to RMEC was significantly higher than to AEC(p < 0.05), suggesting that RMEC are more immunogenic than AEC. Transcriptome sequencing of GGTA1/CMAH DKO pigs indicated that the expression of 1,500 genes was higher in RMEC than in AEC, while expression of 896 genes was lower. Next, we selected 101 candidate genes expressed only in pig RMEC, but not in pig AEC or in monkey or human RMEC. When these genes were knocked out individually in GGTA1/CMAH DKO RMEC, 32 genes were associated with reduced antibody binding, indicating that these genes might be primary immunologic targets involved in DXR. These genes may be important candidates for deletion in producing pigs against which there is a reduced primate immune response in pig kidney xenograft.
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11
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Walters EM, Asnaf SE, Burlak C. Xenotransplantation literature update, March/April 2017. Xenotransplantation 2017; 24. [PMID: 28593725 DOI: 10.1111/xen.12316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Eric M Walters
- Division of Animal Sciences, National Swine Resource and Research Center, University of Missouri-Columbia, Columbia, MO, USA
| | - Sheida Etehad Asnaf
- Department of Surgery, Schultz Diabetes Institutes, University of Minnesota School of Medicine, Minneapolis, MN, USA
| | - Christopher Burlak
- Department of Surgery, Schultz Diabetes Institutes, University of Minnesota School of Medicine, Minneapolis, MN, USA
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