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Ali A, Kemter E, Wolf E. Advances in Organ and Tissue Xenotransplantation. Annu Rev Anim Biosci 2024; 12:369-390. [PMID: 37906838 DOI: 10.1146/annurev-animal-021122-102606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
End-stage organ failure can result from various preexisting conditions and occurs in patients of all ages, and organ transplantation remains its only treatment. In recent years, extensive research has been done to explore the possibility of transplanting animal organs into humans, a process referred to as xenotransplantation. Due to their matching organ sizes and other anatomical and physiological similarities with humans, pigs are the preferred organ donor species. Organ rejection due to host immune response and possible interspecies infectious pathogen transmission have been the biggest hurdles to xenotransplantation's success. Use of genetically engineered pigs as tissue and organ donors for xenotransplantation has helped to address these hurdles. Although several preclinical trials have been conducted in nonhuman primates, some barriers still exist and demand further efforts. This review focuses on the recent advances and remaining challenges in organ and tissue xenotransplantation.
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Affiliation(s)
- Asghar Ali
- Molecular Animal Breeding and Biotechnology, Gene Center and Department of Veterinary Sciences, LMU Munich, Munich, Germany; , ,
- Center for Innovative Medical Models (CiMM), LMU Munich, Oberschleißheim, Germany
- Interfaculty Center for Endocrine and Cardiovascular Disease Network Modelling and Clinical Transfer (ICONLMU), LMU Munich, Munich, Germany
| | - Elisabeth Kemter
- Molecular Animal Breeding and Biotechnology, Gene Center and Department of Veterinary Sciences, LMU Munich, Munich, Germany; , ,
- Center for Innovative Medical Models (CiMM), LMU Munich, Oberschleißheim, Germany
- Interfaculty Center for Endocrine and Cardiovascular Disease Network Modelling and Clinical Transfer (ICONLMU), LMU Munich, Munich, Germany
| | - Eckhard Wolf
- Molecular Animal Breeding and Biotechnology, Gene Center and Department of Veterinary Sciences, LMU Munich, Munich, Germany; , ,
- Center for Innovative Medical Models (CiMM), LMU Munich, Oberschleißheim, Germany
- Interfaculty Center for Endocrine and Cardiovascular Disease Network Modelling and Clinical Transfer (ICONLMU), LMU Munich, Munich, Germany
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Leonova EI, Reshetnikov VV, Sopova JV. CRISPR/Cas-edited pigs for personalized medicine: more than preclinical test-system. RESEARCH RESULTS IN PHARMACOLOGY 2022. [DOI: 10.3897/rrpharmacology.8.83872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Novel CRISPR-Cas-based genome editing tools made it feasible to introduce a variety of precise genomic modifications in the pig genome, including introducing multiple edits simultaneously, inserting long DNA sequences into specifically targeted loci, and performing nucleotide transitions and transversions. Pigs serve as a vital agricultural resource and animal model in biomedical studies, given their advantages over the other models. Pigs share high similarities to humans regarding body/organ size, anatomy, physiology, and a metabolic profile. The pig genome can be modified to carry the same genetic mutations found in humans to replicate inherited diseases to provide preclinical trials of drugs. Moreover, CRISPR-based modification of pigs antigen profile makes it possible to offer porcine organs for xenotransplantation with minimal transplant rejection responses. This review summarizes recent advances in endonuclease-mediated genome editing tools and research progress of genome-edited pigs as personalized test-systems for preclinical trials and as donors of organs with human-fit antigen profile.
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Zhou Q, Li T, Wang K, Zhang Q, Geng Z, Deng S, Cheng C, Wang Y. Current status of xenotransplantation research and the strategies for preventing xenograft rejection. Front Immunol 2022; 13:928173. [PMID: 35967435 PMCID: PMC9367636 DOI: 10.3389/fimmu.2022.928173] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 07/07/2022] [Indexed: 12/13/2022] Open
Abstract
Transplantation is often the last resort for end-stage organ failures, e.g., kidney, liver, heart, lung, and pancreas. The shortage of donor organs is the main limiting factor for successful transplantation in humans. Except living donations, other alternatives are needed, e.g., xenotransplantation of pig organs. However, immune rejection remains the major challenge to overcome in xenotransplantation. There are three different xenogeneic types of rejections, based on the responses and mechanisms involved. It includes hyperacute rejection (HAR), delayed xenograft rejection (DXR) and chronic rejection. DXR, sometimes involves acute humoral xenograft rejection (AHR) and cellular xenograft rejection (CXR), which cannot be strictly distinguished from each other in pathological process. In this review, we comprehensively discussed the mechanism of these immunological rejections and summarized the strategies for preventing them, such as generation of gene knock out donors by different genome editing tools and the use of immunosuppressive regimens. We also addressed organ-specific barriers and challenges needed to pave the way for clinical xenotransplantation. Taken together, this information will benefit the current immunological research in the field of xenotransplantation.
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Affiliation(s)
- Qiao Zhou
- Department of Rheumatology and Immunology, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Clinical Immunology Translational Medicine Key Laboratory of Sichuan Province, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Chinese Academy of Sciences Sichuan Translational Medicine Research Hospital, Chengdu, China
| | - Ting Li
- Department of Rheumatology, Wenjiang District People’s Hospital, Chengdu, China
| | - Kaiwen Wang
- School of Medicine, Faculty of Medicine and Health, The University of Leeds, Leeds, United Kingdom
| | - Qi Zhang
- School of Medicine, University of Electronics and Technology of China, Chengdu, China
| | - Zhuowen Geng
- School of Medicine, Faculty of Medicine and Health, The University of Leeds, Leeds, United Kingdom
| | - Shaoping Deng
- Clinical Immunology Translational Medicine Key Laboratory of Sichuan Province, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Chinese Academy of Sciences Sichuan Translational Medicine Research Hospital, Chengdu, China
- Institute of Organ Transplantation, Sichuan Academy of Medical Science and Sichuan Provincial People’s Hospital, Chengdu, China
| | - Chunming Cheng
- Department of Radiation Oncology, James Comprehensive Cancer Center and College of Medicine at The Ohio State University, Columbus, OH, United States
- *Correspondence: Chunming Cheng, ; Yi Wang,
| | - Yi Wang
- Department of Critical Care Medicine, Sichuan Academy of Medical Science and Sichuan Provincial People's Hospital, Chengdu, China
- *Correspondence: Chunming Cheng, ; Yi Wang,
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Hara H, Iwase H, Nguyen H, Miyagawa Y, Kuravi K, Foote JB, Eyestone W, Phelps C, Ayares D, Cooper DKC. Stable expression of the human thrombomodulin transgene in pig endothelial cells is associated with a reduction in the inflammatory response. Cytokine 2021; 148:155580. [PMID: 34099346 DOI: 10.1016/j.cyto.2021.155580] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 05/10/2021] [Accepted: 05/11/2021] [Indexed: 01/31/2023]
Abstract
BACKGROUND Xenotransplantation is associated with an inflammatory response. The proinflammatory cytokine, TNF-α, downregulates the expression of thrombomodulin (TBM), and induces coagulation dysfunction. Although human (h) TBM-transgenic pigs (p) have been developed to reduce coagulation dysfunction, the effect of TNF-α on the expression of hTBM and its functional activity has not been fully investigated. The aims of this study were to investigate (i) whether the expression of hTBM on pig (p) cells is down-regulated during TNF-α stimulation, and (ii) whether cells from hTBM pigs regulate the inflammatory response. METHODS TNF-α-producing T, B, and natural killer cells in blood from baboons with pig heart or kidney xenografts were investigated by flow cytometry. TNF-α staining in the grafts was detected by immunohistochemistry. Aortic endothelial cells (AECs) from GTKO/CD46 and GTKO/CD46/hTBM pigs were stimulated by hTNF-α, and the expression of the inflammatory/coagulation regulatory protein, TBM, was investigated. RESULTS After pig organ xenotransplantation, there was a trend to increases in TNF-α-producing T and natural killer cells in the blood of baboons. In vitro observations demonstrated that after hTNF-α stimulation, there was a significant reduction in the expression of endogenous pTBM on pAECs, and a significant increase in the expression of inflammatory molecules. Blocking of NF-κB signaling significantly up-regulated pTBM expression, and suppressed the inflammatory response induced by hTNF-α in pAECs. Whereas the expression of pTBM mRNA was significantly reduced by hTNF-α stimulation, hTBM expression on the GTKO/CD46/hTBM pAECs was not affected. Furthermore, after hTNF-α stimulation, there was significant suppression of expression of inflammatory molecules on GTKO/CD46/hTBM pAECs compared to GTKO/CD46 pAECs. CONCLUSIONS The stable expression of hTBM in pig cells may locally regulate the inflammatory response. This will help suppress the inflammatory response and prevent coagulation dysregulation after xenotransplantation.
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Affiliation(s)
- Hidetaka Hara
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA; Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA.
| | - Hayato Iwase
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA; Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Huy Nguyen
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Yuko Miyagawa
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
| | | | - Jeremy B Foote
- Department of Microbiology and Animal Resources Program, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | | | | | - David K C Cooper
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
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Cho B, Choi I, Lee EM, Hurh S, Lee BC, Ahn C. Up-regulation of fibrinogen-like protein 2 in porcine endothelial cells by xenogeneic CD40 signal. Anim Cells Syst (Seoul) 2018; 22:92-99. [PMID: 30460085 PMCID: PMC6138318 DOI: 10.1080/19768354.2018.1433718] [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: 12/22/2017] [Accepted: 01/24/2018] [Indexed: 11/05/2022] Open
Abstract
Acute humoral xenograft rejection (AHXR), characterized by thrombin generation and endothelial cell activation, should be overcome for the success of xenotransplantation. Fibrinogen-like protein 2 (fgl2) expressed on endothelial cells can convert prothrombin to thrombin directly, which indicates that the induced fgl2 expression in activated endothelial cells can contribute to thrombosis. In xenotransplant condition, the interaction between human CD40L and porcine endothelial CD40 can activate endothelial cells. In this study, we investigated the effect of endothelial cell activation through the interaction between human CD40L and porcine CD40 on fgl2 expression and its function as a direct prothrombinase. We found that CD40 stimulation up-regulated fgl2 expression as well as its enzymatic activity in porcine endothelial cells. Moreover, functional studies using knock-down system showed that the major factor converting human prothrombin to thrombin is fgl2 protein expressed on porcine endothelial cells. Overall, this study demonstrates that fgl2 expression can be induced by xenogeneic CD40 signal on endothelial cells and contribute to thrombin generation.
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Affiliation(s)
- Bumrae Cho
- Biotechnology Research Institute, Mgenplus Co., Ltd., Seoul, Republic of Korea.,Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.,Research Institute for Veterinary Science, Seoul National University, Seoul, Republic of Korea
| | - Inho Choi
- Department of Pharmaceutical Engineering, College of Life and Health Sciences, Hoseo University, Asan, Republic of Korea
| | - Eun Mi Lee
- Center for Medical Innovation, Biomedical Research Institute, Seoul National University Hospital, Seoul, Korea.,Graduate School of Translational Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Sunghoon Hurh
- Center for Medical Innovation, Biomedical Research Institute, Seoul National University Hospital, Seoul, Korea.,Graduate School of Translational Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Byeong Chun Lee
- Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.,Research Institute for Veterinary Science, Seoul National University, Seoul, Republic of Korea
| | - Curie Ahn
- Graduate School of Translational Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.,Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
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Vascularized Thymosternal Composite Tissue Allo- and Xenotransplantation in Nonhuman Primates: Initial Experience. PLASTIC AND RECONSTRUCTIVE SURGERY-GLOBAL OPEN 2018; 5:e1538. [PMID: 29632759 PMCID: PMC5889452 DOI: 10.1097/gox.0000000000001538] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 08/29/2017] [Indexed: 01/07/2023]
Abstract
Background: Vascularized composite allotransplantation is constrained by complications associated with standard immunosuppressive strategies. Vascularized thymus and bone marrow have been shown to promote prolonged graft survival in composite organ and soft-tissue vascularized composite allotransplantation models. We report development of a nonhuman primate vascularized thymosternal composite tissue transplant model as a platform to address donor-specific immune tolerance induction strategies. Methods: Vascularized thymosternal allograft (skin, muscle, thymus, sternal bone) was transplanted between MHC-mismatched rhesus monkeys (feasibility studies) and baboons (long-term survival studies), with end-to-side anastomoses of the donor aorta and SVC to the recipient common femoral vessels. A male allograft was transplanted to a female’s lower abdominal wall, and clinically applicable immunosuppression was given. Skin biopsies and immunological assays were completed at regular intervals, and chimerism was quantified using polymerase chain reaction specific for baboon Y chromosome. Results: Four allo- and 2 xenotransplants were performed, demonstrating consistent technical feasibility. In 1 baboon thymosternal allograft recipient treated with anti-CD40–based immunosuppression, loss of peripheral blood microchimerism after day 5 was observed and anticipated graft rejection at 13 days. In the second allograft, when cutaneous erythema and ecchymosis with allograft swelling was treated with anti-thymocyte globulin starting on day 6, microchimerism persisted until immunosuppression was reduced after the first month, and the allograft survived to 87 days, 1 month after cessation of immunosuppression treatment. Conclusions: We established both allo- and xeno- composite vascularized thymosternal transplant preclinical models, which will be useful to investigate the role of primarily vascularized donor bone marrow and thymus.
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Lee SC, Lee H, Oh KB, Hwang IS, Yang H, Park MR, Ock SA, Woo JS, Im GS, Hwang S. Production and Breeding of Transgenic Cloned Pigs Expressing Human CD73. Dev Reprod 2017; 21:157-165. [PMID: 28785737 PMCID: PMC5532308 DOI: 10.12717/dr.2017.21.2.157] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 05/04/2017] [Accepted: 05/08/2017] [Indexed: 11/17/2022]
Abstract
One of the reasons to causing blood coagulation in the tissue of xenografted
organs was known to incompatibility of the blood coagulation and
anti-coagulation regulatory system between TG pigs and primates. Thus,
overexpression of human CD73 (hCD73) in the pig endothelial cells is considered
as a method to reduce coagulopathy after pig-to-non-human-primate
xenotransplantation. This study was performed to produce and breed transgenic
pigs expressing hCD73 for the studies immune rejection responses and could
provide a successful application of xenotransplantation. The transgenic cells
were constructed an hCD73 expression vector under control porcine Icam2 promoter
(pIcam2-hCD73) and established donor cell lines expressing hCD73. The numbers of
transferred reconstructed embryos were 127 ± 18.9. The pregnancy and delivery
rate of surrogates were 8/18 (44%) and 3/18 (16%). The total number of delivered
cloned pigs were 10 (2 alive, 7 mummy, and 1 died after birth). Among them,
three live hCD73-pigs were successfully delivered by Caesarean section, but one
was dead after birth. The two hCD73 TG cloned pigs had normal reproductive
ability. They mated with wild type (WT) MGH (Massachusetts General Hospital)
female sows and produced totally 16 piglets. Among them, 5 piglets were
identified as hCD73 TG pigs. In conclusion, we successfully generated the hCD73
transgenic cloned pigs and produced their litters by natural mating. It can be
possible to use a mate for the production of multiple transgenic pigs such as
α-1,3-galactosyltransferase knock-out /hCD46 for xenotransplantation.
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Affiliation(s)
- Seung-Chan Lee
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Haesun Lee
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Keon Bong Oh
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - In-Sul Hwang
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Hyeon Yang
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Mi-Ryung Park
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Sun-A Ock
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Jae-Seok Woo
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Gi-Sun Im
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
| | - Seongsoo Hwang
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju 55365, Republic of Korea
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Béland S, Vallin P, Désy O, Lévesque E, De Serres SA. Effects of alloantibodies to human leukocyte antigen on endothelial expression and serum levels of thrombomodulin. J Thromb Haemost 2017; 15:1020-1031. [PMID: 28239987 DOI: 10.1111/jth.13661] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Indexed: 12/25/2022]
Abstract
Essentials The effect of alloantibodies on the endothelial expression of thrombomodulin is unknown. Thrombomodulin was quantified in stimulated endothelial cells and measured in serum samples. Anti-human leukocyte antigen (HLA) I vs. II antibodies have different effects on thrombomodulin. Anti-HLA II antibodies may promote a prothrombotic state and contribute to microangiopathy. SUMMARY Rationale Thrombomodulin (TBM) is an anticoagulant and anti-inflammatory transmembrane protein expressed on endothelial cells. Donor-specific alloantibodies, particularly those against human leukocyte antigen (HLA) class II, are associated with microvascular endothelial damage in solid allografts. Objective Our aim was to characterize the effects of anti-HLA antibodies on endothelial expression of TBM, and in particular, the differential effects of anti-HLA class I compared with those of anti-HLA class II. Methods We used human glomerular microvascular endothelial cells to examine TBM expression on anti-HLA-treated cells, and we tested sera from transplant recipients for soluble TBM. Results We found that whereas membrane TBM expression increased in a dose-dependent manner in the presence of anti-HLA class I antibodies, treatment with anti-HLA class II led to minimal TBM expression on the endothelial surface but to a cytosolic accumulation. Platelet adhesion studies confirmed the functional impact of anti-HLA class II. Quantitative densitometry of the membrane lysates further suggested that anti-HLA class II impairs TBM glycosylation. Furthermore, we found a significant association between the presence of circulating anti-HLA class II antibodies in transplant recipients and low serum levels of TBM. Conclusion These results indicate that ligation of anti-HLA class I and II antibodies produces different effects on the endothelial expression of TBM and on serum levels of TBM in transplant recipients. Anti-HLA class II antibodies may be associated with a prothrombotic state, which could explain the higher occurrence of microangiopathic lesions in the allograft and the poor outcomes observed in patients with these alloantibodies.
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Affiliation(s)
- S Béland
- Transplantation Unit, Renal Division, Department of Medicine, University Health Center of Quebec, Faculty of Medicine, Laval University, Quebec City, QC, Canada
| | - P Vallin
- Transplantation Unit, Renal Division, Department of Medicine, University Health Center of Quebec, Faculty of Medicine, Laval University, Quebec City, QC, Canada
| | - O Désy
- Transplantation Unit, Renal Division, Department of Medicine, University Health Center of Quebec, Faculty of Medicine, Laval University, Quebec City, QC, Canada
| | - E Lévesque
- Hematology and Oncology Division, Department of Medicine, University Health Center of Quebec, Faculty of Medicine, Laval University, Quebec City, QC, Canada
| | - S A De Serres
- Transplantation Unit, Renal Division, Department of Medicine, University Health Center of Quebec, Faculty of Medicine, Laval University, Quebec City, QC, Canada
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Ramackers W, Klose J, Tiede A, Werwitzke S, Rataj D, Friedrich L, Johanning K, Vondran FWR, Bergmann S, Schuettler W, Bockmeyer CL, Becker JU, Klempnauer J, Winkler M. Effect of TNF-alpha blockade on coagulopathy and endothelial cell activation in xenoperfused porcine kidneys. Xenotransplantation 2016. [PMID: 26216261 DOI: 10.1111/xen.12179] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND Following pig-to-primate kidney transplantation, endothelial cell activation and xenogenic activation of the recipient's coagulation eventually leading to organ dysfunction and microthrombosis can be observed. In this study, we examined the effect of a TNF-receptor fusion protein (TNF-RFP) on endothelial cell activation and coagulopathy utilizing an appropriate ex vivo perfusion system. METHODS Using an ex vivo perfusion circuit based on C1-Inhibitor (C1-Inh) and low-dose heparin administration, we have analyzed consumptive coagulopathy following contact of human blood with porcine endothelium. Porcine kidneys were recovered following in situ cold perfusion with Histidine-tryptophan-ketoglutarate (HTK) organ preservation solution and were immediately connected to a perfusion circuit utilizing freshly drawn pooled porcine or human AB blood. The experiments were performed in three individual groups: autologous perfusion (n = 5), xenogenic perfusion without any further pharmacological intervention (n = 10), or with addition of TNF-RFP (n = 5). After perfusion, tissue samples were obtained for real-time PCR and immunohistological analyses. Endothelial cell activation was assessed by measuring the expression levels of E-selectin, ICAM-1, and VCAM-1. RESULTS Kidney survival during organ perfusion with human blood, C1-Inh, and heparin, but without any further pharmacological intervention was 126 ± 78 min. Coagulopathy was observed with significantly elevated concentrations of D-dimer and thrombin-antithrombin complex (TAT), resulting in the formation of multiple microthrombi. Endothelial cell activation was pronounced, as shown by increased expression of E-selectin and VCAM-1. In contrast, pharmacological intervention with TNF-RFP prolonged organ survival to 240 ± 0 min (max. perfusion time; no difference to autologous control). Formation of microthrombi was slightly reduced, although not significantly, if compared to the xenogenic control. D-dimer and TAT were elevated at similar levels to the xenogenic control experiments. In contrast, endothelial cell activation, as shown by real-time PCR, was significantly reduced in the TNF-RFP group. CONCLUSION We conclude that although coagulopathy was not affected, TNF-RFP is able to suppress inflammation occurring after xenoperfusion in this ex vivo perfusion model.
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Affiliation(s)
- Wolf Ramackers
- Klinik für Allgemein-, Viszeral- und Transplantationschirurgie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Johannes Klose
- Klinik für Allgemein-, Viszeral- und Transplantationschirurgie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Andreas Tiede
- Klinik für Haematologie, Haemostaseologie, Onkologie und Stammzelltransplantation, Medizinische Hochschule Hannover, Hannover, Germany
| | - Sonja Werwitzke
- Klinik für Haematologie, Haemostaseologie, Onkologie und Stammzelltransplantation, Medizinische Hochschule Hannover, Hannover, Germany
| | - Dennis Rataj
- Klinik für Haematologie, Haemostaseologie, Onkologie und Stammzelltransplantation, Medizinische Hochschule Hannover, Hannover, Germany
| | - Lars Friedrich
- Klinik für Anaesthesiologie und Intensivmedizin, Medizinische Hochschule Hannover, Hannover, Germany
| | - Kai Johanning
- Klinik für Anaesthesiologie und Intensivmedizin, Medizinische Hochschule Hannover, Hannover, Germany
| | - Florian W R Vondran
- Klinik für Allgemein-, Viszeral- und Transplantationschirurgie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Sabine Bergmann
- Klinik für Allgemein-, Viszeral- und Transplantationschirurgie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Wolfgang Schuettler
- Klinik für Allgemein-, Viszeral- und Transplantationschirurgie, Medizinische Hochschule Hannover, Hannover, Germany
| | | | - Jan Ulrich Becker
- Institut für Pathologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Jürgen Klempnauer
- Klinik für Allgemein-, Viszeral- und Transplantationschirurgie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Michael Winkler
- Klinik für Allgemein-, Viszeral- und Transplantationschirurgie, Medizinische Hochschule Hannover, Hannover, Germany
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Kim H, Hawthorne WJ, Kang HJ, Lee YJ, Hwang J, Hurh S, Ro H, Jeong JC, Cho B, Yang J, Ahn C. Human thrombomodulin regulates complement activation as well as the coagulation cascade in xeno‐immune response. Xenotransplantation 2015; 22:260-272. [DOI: 10.1111/xen.12173] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Affiliation(s)
- Hwajung Kim
- Transplantation Research Institute Seoul National University Seoul Korea
| | - Wayne J. Hawthorne
- Centre for Transplant and Renal Research Westmead Millennium Institute The University of Sydney at Westmead Hospital Westmead NSW Australia
| | - Hee Jung Kang
- Department of Laboratory Medicine Hallym University College of Medicine Anyang Korea
| | - Yoo Jin Lee
- Transplantation Research Institute Seoul National University Seoul Korea
| | - Jong‐Ik Hwang
- Graduate School of Medicine Korea University Seoul Korea
| | - Sunghoon Hurh
- Transplantation Research Institute Seoul National University Seoul Korea
| | - Han Ro
- Gachon University Gil Medical Center Inchon Korea
| | - Jong Cheol Jeong
- Transplantation Research Institute Seoul National University Seoul Korea
- Transplantation Center Seoul National University Hospital Seoul Korea
| | - Bumrae Cho
- Designed Animal & Transplantation Research Institute Institute of Green Bio Science & Technology Seoul National University Pyeongchang Gangwon‐do Korea
| | - Jaeseok Yang
- Transplantation Research Institute Seoul National University Seoul Korea
- Transplantation Center Seoul National University Hospital Seoul Korea
| | - Curie Ahn
- Transplantation Research Institute Seoul National University Seoul Korea
- Transplantation Center Seoul National University Hospital Seoul Korea
- Designed Animal & Transplantation Research Institute Institute of Green Bio Science & Technology Seoul National University Pyeongchang Gangwon‐do Korea
- Division of Nephrology Seoul National University College of Medicine Seoul Korea
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De Giorgi M, Pelikant-Malecka I, Sielicka A, Slominska EM, Giovannoni R, Cinti A, Cerrito MG, Lavitrano M, Smolenski RT. Functional analysis of expression of human ecto-nucleoside triphosphate diphosphohydrolase-1 and/or ecto-5'-nucleotidase in pig endothelial cells. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2015; 33:313-8. [PMID: 24940685 DOI: 10.1080/15257770.2014.896466] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Adenine nucleosides and nucleotides are important signaling molecules involved in control of key mechanisms of xenotransplant rejection. Extracellular pathway that converts ATP and ADP to AMP, and AMP to adenosine mainly mediated by ecto-nucleoside triphosphate diphosphohydrolase 1, (ENTPD1 or CD39) and ecto-5'-nucleotidase (E5NT or CD73) respectively, is considered as important target for xenograft protection. To clarify feasibility of combined expression of human ENTPD1 and E5NT and to study its functional effect we transfected pig endothelial cell line (PIEC) with both genes together. To do this we have produced a dicistronic construct bearing F2A sequence in frame between human E5NT and human ENTPD1 coding sequences. PIEC cells were mock-transfected as transfection control or transfected with plasmids encoding human ENTPD1 or human E5NT. PIEC cells were exposed to 50 μM ATP or 50 μM ADP or 50 μM AMP. Conversion of extracellular substrates into products (ATP/ADP/AMP/adenosine) was measured by HPLC in the media collected at specific time intervals. Following addition of AMP, production of adenosine in the medium of E5NT/ENTPD1- and E5NT- transfected cells increased to 14.2±1.1 and 24.5±3.4 μM respectively while it remained below 1 μM in controls and in ENTPD1-transfected cells. A marked increase of adenosine formation from ADP or ATP was observed only in E5NT/ENTPD1-transfected cells (11.7±0.1 and 5.7±2.2 μM respectively) but not in any other condition studied. This study indicates feasibility and functionality of combined expression of human E5NT and ENTPD1 in pig endothelial cells using F2A sequence bearing construct.
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Affiliation(s)
- M De Giorgi
- a Department of Surgery and Translational Medicine , University of Milano-Bicocca , Milano , Italy
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De Salvatore S, Segreto A, Chiusaroli A, Congiu S, Bizzarri F. Role of xenotransplantation in cardiac transplantation. J Card Surg 2014; 30:111-6. [PMID: 25345720 DOI: 10.1111/jocs.12454] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This review will discuss the history and development of the field of genetic modification, up to the most recent scientific discoveries, and will also consider the current uses of genetic therapy.
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Affiliation(s)
- Sergio De Salvatore
- Department of Science and Medical-Surgical Biotechnologies, Cardiac Surgery Unit, Universita' degli Studi di Roma "Sapienza", Latina, Italy
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Burdorf L, Stoddard T, Zhang T, Rybak E, Riner A, Avon C, Laaris A, Cheng X, Sievert E, Braileanu G, Newton A, Phelps CJ, Ayares D, Azimzadeh AM, Pierson RN. Expression of human CD46 modulates inflammation associated with GalTKO lung xenograft injury. Am J Transplant 2014; 14:1084-95. [PMID: 24698431 PMCID: PMC4144189 DOI: 10.1111/ajt.12673] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 12/06/2013] [Accepted: 01/12/2014] [Indexed: 01/25/2023]
Abstract
Evaluation of lungs from GalTKO.hCD46 pigs, genetically modified to lack the galactose-α(1,3)-galactose epitope (GalTKO) and to express human CD46, a complement regulatory protein, has not previously been described. Physiologic, hematologic and biochemical parameters during perfusion with heparinized fresh human blood were measured for 33 GalTKO.hCD46, GalTKO (n = 16), and WT pig lungs (n = 16), and 12 pig lungs perfused with autologous pig blood. Median GalTKO.hCD46 lung survival was 171 min compared to 120 for GalTKO (p = 0.27) and 10 for WT lungs (p < 0.001). Complement activation, platelet activation and histamine elaboration were significantly reduced during the first 2 h of perfusion in GalTKO.hCD46 lungs compared to GalTKO (ΔC3a at 120' 812 ± 230 vs. 1412 ± 1047, p = 0.02; ΔCD62P at 120' 9.8 ± 7.2 vs. 25.4 ± 18.2, p < 0.01; Δhistamine at 60' 97 ± 62 vs. 189 ± 194, p = 0.03). We conclude that, in addition to significant down-modulation of complement activation, hCD46 expression in GalTKO lungs diminished platelet and coagulation cascade activation, neutrophil sequestration and histamine release. Because GalTKO.hCD46 lung failure kinetics correlated directly with platelet and neutrophil sequestration, coagulation cascade activation and a rise in histamine levels within the first hour of perfusion, further progress will likely depend upon improved control of these pathways, by rationally targeted additional modifications to pigs and pharmacologic interventions.
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Affiliation(s)
- L Burdorf
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - T Stoddard
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - T Zhang
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - E Rybak
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - A Riner
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - C Avon
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - A Laaris
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - X Cheng
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - E Sievert
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - G Braileanu
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - A Newton
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - C J Phelps
- Revivicor, Inc., Blacksburg, VA, United States
| | - D Ayares
- Revivicor, Inc., Blacksburg, VA, United States
| | - A M Azimzadeh
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - R N Pierson
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
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Iwase H, Ezzelarab MB, Ekser B, Cooper DKC. The role of platelets in coagulation dysfunction in xenotransplantation, and therapeutic options. Xenotransplantation 2014; 21:201-20. [PMID: 24571124 DOI: 10.1111/xen.12085] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 01/08/2014] [Indexed: 12/11/2022]
Abstract
Xenotransplantation could resolve the increasing discrepancy between the availability of deceased human donor organs and the demand for transplantation. Most advances in this field have resulted from the introduction of genetically engineered pigs, e.g., α1,3-galactosyltransferase gene-knockout (GTKO) pigs transgenic for one or more human complement-regulatory proteins (e.g., CD55, CD46, CD59). Failure of these grafts has not been associated with the classical features of acute humoral xenograft rejection, but with the development of thrombotic microangiopathy in the graft and/or consumptive coagulopathy in the recipient. Although the precise mechanisms of coagulation dysregulation remain unclear, molecular incompatibilities between primate coagulation factors and pig natural anticoagulants exacerbate the thrombotic state within the xenograft vasculature. Platelets play a crucial role in thrombosis and contribute to the coagulation disorder in xenotransplantation. They are therefore important targets if this barrier is to be overcome. Further genetic manipulation of the organ-source pigs, such as pigs that express one or more coagulation-regulatory genes (e.g., thrombomodulin, endothelial protein C receptor, tissue factor pathway inhibitor, CD39), is anticipated to inhibit platelet activation and the generation of thrombus. In addition, adjunctive pharmacologic anti-platelet therapy may be required. The genetic manipulations that are currently being tested are reviewed, as are the potential pharmacologic agents that may prove beneficial.
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Affiliation(s)
- Hayato Iwase
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
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Diswall M, Benktander J, Ångström J, Teneberg S, Breimer ME. The alpha1,3GalT knockout/alpha1,2FucT transgenic pig does not appear to have an advantage over the alpha1,3GalT knockout pig with respect to glycolipid reactivity with human serum antibodies. Xenotransplantation 2013; 21:57-71. [PMID: 24219248 DOI: 10.1111/xen.12071] [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: 05/21/2013] [Accepted: 10/02/2013] [Indexed: 11/29/2022]
Abstract
BACKGROUND The human H-transferase (α2FucT) was introduced in Gal-negative pigs to produce pig organs not only free from Gal-antigens, but also in which the uncapped N-acetyllactosamine precursor had been transformed into non-xenogenic blood group H type 2 compounds. This work is the first descriptive analysis of glycolipids from the GalT-KO/FucT-TG pig. The aim was to investigate the cell membrane antigens in GalT-KO/FucT-TG tissues to explore its efficacy as an organ donor. Also, detailed knowledge on the correlation between the cellular glycosyltransferase configuration and the resulting carbohydrate phenotype expression is valuable from a basic glycobiological perspective. METHODS Neutral and acidic glycolipids from GalT-KO/FucT-TG small intestine were compared with glycolipids from two wildtype and two GalT-KO pig intestines. Glycolipid reactivity was tested on thin layer chromatography plates using chemical reagents, antibodies, lectins, and human serum. Structural characterization of neutral glycolipids was performed by LC-ESI/MS and proton NMR spectroscopy. RESULTS Characterization of the glycolipid expression in GalT-KO/FucT-TG intestine showed absence of Gal antigens and decreased/unchanged levels of the N-acetyllactosamine precursor and the blood group H type 2 expression, when compared with the wildtype. The reactivity of human serum antibodies to GalT-KO/FucT-TG derived glycolipids was similar or slightly elevated when compared with GalT-KO glycolipids. Results from LC-ESI/MS and proton NMR spectroscopy revealed no established neutral xenogenic antigens in the GalT-KO/FucT-TG pig, and could thus not explain the immunologic reactivity to human serum antibodies. The antibody binding to acidic glycolipids is most likely to be explained by the abundance of N-glycolylneuraminic acid epitopes in pig tissues. Six neutral complex biantennary glycolipids with blood group H type 1, 2, Lewis(x) and Lewis(y) determinants were found, of which three were identified in this work for the first time. One of these was a nonaglycosylceramide with blood group H type 2 and lactosyl determinants linked to a lactotetraosyl core, and the other two were decaglycosylceramides with blood group H type 1 and H type 2 determinants linked to a neolactotetraosyl core, and Lewis(x) and blood group H type 1 determinants on a lactotetraosyl core, respectively. CONCLUSIONS Lipid-linked carbohydrate antigens in the GalT-KO/FucT-TG pig intestine showed no or minor qualitative difference when compared with GalT-KO pigs. The GalT-KO/FucT-TG pig did not appear to have an advantage over the GalT-KO pig with respect to reactivity with human antibodies from a xenotransplantation perspective.
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Affiliation(s)
- Mette Diswall
- Department of Surgery, Institute of Clinical Sciences, Sahlgrenska Academy/Gothenburg University, Gothenburg, Sweden; Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
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Hara H, Bentall A, Long C, Fang J, Andreyev O, Lunz J, Ezzelarab M, Abu-Elmagd KM, Shapiro R, Ayares D, Stegall M, Cooper DKC. Minimal effect of bortezomib in reducing anti-pig antibodies in human leukocyte antigen-sensitized patients: a pilot study. Xenotransplantation 2013; 20:429-37. [PMID: 23998233 DOI: 10.1111/xen.12052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 07/31/2013] [Indexed: 12/24/2022]
Abstract
BACKGROUND Bortezomib, a proteasome inhibitor used to treat multiple myeloma, has been administered (± plasma exchange ± intravenous immunoglobulin [IVIg]) in attempts to reduce antibodies against human leukocyte antigens (HLA) in sensitized patients undergoing organ transplantation. To our knowledge, bortezomib has not been investigated for its effect on natural anti-pig antibodies. If bortezomib could reduce the production of anti-pig antibodies, this would likely be beneficial to the outcome of pig organ grafts in primates. METHODS Nine patients received bortezomib either to reduce anti-HLA antibody levels before organ allotransplantation or to treat antibody-mediated rejection. Patients at the Mayo Clinic (Group 1; n = 4) received bortezomib alone, whereas at the UPMC (Group 2; n = 5), this was combined with plasmaphereses ± IVIg in some cases. Anti-pig IgM and IgG levels against wild-type (WT) and α1,3-galactosyltransferase gene knockout (GTKO) pig aortic endothelial cells (flow cytometry-relative mean fluorescence intensity) and anti-Gal IgM and IgG (ELISA-OD480 nm ) were measured pre- and post-bortezomib therapy. RESULTS Mean anti-pig IgM levels were 11.2 (WT) and 1.9 (GTKO) pre-bortezomib treatment and 9.4 (WT: P = 0.02) and 1.7 (GTKO: P = 0.33) post-bortezomib treatment, respectively. Mean anti-pig IgG levels were 4.3 (WT) and 1.5 (GTKO) pre-bortezomib treatment and 3.6 (WT: P = 0.21) and 1.4 (GTKO: P = 0.20) post-bortezomib treatment, respectively. Mean anti-Gal IgM and IgG levels were 0.7 and 1.1, respectively, pre-treatment, and 0.6 (P = 0.03) and 1.1 (NS), respectively, post-treatment. When the data were analyzed in Groups 1 and 2 separately, there were no significant differences between the pre- and post-bortezomib levels of anti-pig, anti-non-Gal, or anti-Gal IgM or IgG. CONCLUSIONS From this limited study, we conclude that bortezomib might reduce anti-Gal IgM levels in primates, but, in this respect alone, is unlikely to have any significant effect on the outcome of GTKO pig organ transplantation.
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Affiliation(s)
- Hidetaka Hara
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
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Ramackers W, Klose J, Winkler M. Xeno-kidney transplantation: from idea to reality. Transplant Proc 2012; 44:1773-5. [PMID: 22841270 DOI: 10.1016/j.transproceed.2012.05.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Although kidney transplantation is a widely used therapy for chronic renal failure, not all patients can be transplanted due to the limited numbers of organ donations. A possible solution could be xenogenic kidney transplantation. Herein we have described the present state, problems and possible solutions using xenograft treatments.
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Affiliation(s)
- W Ramackers
- Department of General, Visceral and Transplantation Surgery, Hannover Medical School, Hannover, Germany.
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Abstract
Microvascular thrombosis, following the activation of clotting cascade, is a hallmark of porcine solid organ xenograft rejection. The analysis of differences between human, monkey, and pig coagulation systems is crucial when monkey is used as animal model and pig as organ donor in xenotransplantation. Thrombosis, according to many authors, may be due to the molecular incompatibilities between natural anticoagulants present on pig endothelium and primate activated coagulation factors. The generation of activated protein C (PC) is critical for the physiological anticoagulation. One of the major incompatibilities may be related to the inability of pig thrombomodulin (TM) and endothelial protein C receptor to activate the recipient (primate) circulating PC in the presence of thrombin. Tissue factor pathway inhibitor (TFPI), is the primary inhibitor of tissue factor (TF)-induced coagulation. TFPI directly inhibits the activated factor X (FXa) and blocks the procoagulant activity of the TF/factor VIIa (FVIIa) complex by forming a quaternary TF/FVIIa/FXa/TFPI complex. Microvascular thrombosis, observed in the organ transplant, may also be due to the failure of pig TFPI to bind human FXa efficiently and inhibit human FVIIa/TF activity. The methods described in this chapter can be useful for the identification and characterization of primate and pig coagulation factors (isolated from a small volume of blood) by using SDS-PAGE and immunoblotting. Differences in molecular weight can help in the identification of the origin (pig or primate) of coagulation proteins in plasma from the recipient of xenografts. On the other hand, in vitro models of PC pathway and TFPI on human umbilical vein endothelial cells (HUVEC) and porcine aortic endothelial cells (PAEC) are described which can be used for studying incompatibilities between primate and pig.
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Devallière J, Charreau B. The adaptor Lnk (SH2B3): an emerging regulator in vascular cells and a link between immune and inflammatory signaling. Biochem Pharmacol 2011; 82:1391-402. [PMID: 21723852 DOI: 10.1016/j.bcp.2011.06.023] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 06/15/2011] [Accepted: 06/16/2011] [Indexed: 12/20/2022]
Abstract
A better knowledge of the process by which inflammatory extracellular signals are relayed from the plasma membrane to specific intracellular sites is a key step to understand how inflammation develops and how it is regulated. This review focuses on Lnk (SH2B3) a member, with SH2B1 and SH2B2, of the SH2B family of adaptor proteins that influences a variety of signaling pathways mediated by Janus kinase and receptor tyrosine kinases. SH2B adaptor proteins contain conserved dimerization, pleckstrin homology, and SH2 domains. Initially described as a regulator of hematopoiesis and lymphocyte differentiation, Lnk now emerges as a key regulator in hematopoeitic and non hematopoeitic cells such as endothelial cells (EC) moderating growth factor and cytokine receptor-mediated signaling. In EC, Lnk is a negative regulator of TNF signaling that reduce proinflammatory phenotype and prevent EC from apoptosis. Lnk is a modulator in integrin signaling and actin cytoskeleton organization in both platelets and EC with an impact on cell adhesion, migration and thrombosis. In this review, we discuss some recent insights proposing Lnk as a key regulator of bone marrow-endothelial progenitor cell kinetics, including the ability to cell growth, endothelial commitment, mobilization, and recruitment for vascular regeneration. Finally, novel findings also provided evidences that mutations in Lnk gene are strongly linked to myeloproliferative disorders but also autoimmune and inflammatory syndromes where both immune and vascular cells display a role. Overall, these studies emphasize the importance of the Lnk adaptor molecule not only as prognostic marker but also as potential therapeutic target.
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Lee HJ, Lee BC, Kim YH, Paik NW, Rho HM. Characterization of Transgenic Pigs That Express Human Decay Accelerating Factor and Cell Membrane-tethered Human Tissue Factor Pathway Inhibitor. Reprod Domest Anim 2011; 46:325-32. [DOI: 10.1111/j.1439-0531.2010.01670.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Identification of new carbohydrate and membrane protein antigens in cardiac xenotransplantation. Transplantation 2011; 91:287-92. [PMID: 21119562 PMCID: PMC10022691 DOI: 10.1097/tp.0b013e318203c27d] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND α1,3-Galactosyltransferase gene knockout (GTKO) pigs reduced the significance of antibody to galactose alpha 1,3-galactose (Gal) antigens but did not eliminate delayed xenograft rejection (DXR). We hypothesize that DXR of GTKO organs results from an antibody response to a limited number of non-Gal endothelial cell (EC) membrane antigens. In this study, we screened a retrovirus expression library to identify EC membrane antigens detected after cardiac xenotransplantation. METHODS Expression libraries were made from GT:CD46 and GTKO porcine aortic ECs. Viral stocks were used to infect human embryonic kidney cells (HEK) that were selected by flow cytometry for IgG binding from sensitized cardiac heterotopic xenograft recipients. After three to seven rounds of selection, individual clones were assessed for non-Gal IgG binding. The porcine complementary DNA was recovered by polymerase chain reaction amplification, sequenced, and identified by homology comparisons. RESULTS A total of 199 and 317 clones were analyzed from GT:CD46 and GTKO porcine aortic EC complementary DNA libraries, respectively. Sequence analysis identified porcine CD9, CD46, CD59, and the EC protein C receptor. We also identified porcine annexin A2 and a glycosyltransferase with homology to the human β1,4 N-acetylgalactosaminyl transferase 2 gene. CONCLUSION The identified proteins include key EC functions and suggest that non-Gal antibody responses may compromise EC functions and thereby contribute to DXR. Recovery of the porcine β1,4 N-acetylgalactosaminyl transferase 2 suggests that an antibody response to a SD-like carbohydrate may represent a new carbohydrate moiety involved in xenotransplantation. The identification of these porcine gene products may lead to further donor modification to enhance resistance to DXR and further reduce the level of xenograft antigenicity.
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Cooper DKC, Ayares D. The immense potential of xenotransplantation in surgery. Int J Surg 2010; 9:122-9. [PMID: 21059418 DOI: 10.1016/j.ijsu.2010.11.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Accepted: 11/02/2010] [Indexed: 01/28/2023]
Abstract
There is a limited availability of deceased human organs and cells for the purposes of clinical transplantation. Genetically-engineered pigs may provide an alternative source. Although several immune barriers need to be overcome, considerable progress has been made in experimental models in recent years, largely through the increasing availability of pigs with new genetic modifications. Pig heterotopic heart graft survival in nonhuman primates has extended for 8 months, with orthotopic grafts supporting life for almost 2 months. Life-supporting kidney transplants have functioned for almost 3 months. The current barriers are related to coagulation dysfunction between pig and primate that results in thrombotic microangiopathy and/or a consumptive coagulopathy, which may in part be related to molecular incompatibilities in the coagulation systems of pigs and primates. Current efforts are concentrated on genetically-modifying the organ- or islet-source pigs by the introduction of 'anticoagulant' or 'anti-thrombotic' genes to provide protection from the recipient coagulation cascade and platelet activation. Progress with pig islet xenotransplantation has been particularly encouraging with complete control of glycemia in diabetic monkeys extending in one case for >12 months. Other areas where experimental data suggest the possibility of early clinical trials are corneal xenotransplantation and pig neuronal cell xenotransplantation, for example, in patients with Parkinson's disease. With the speed of advances in genetic engineering increasing steadily, it is almost certain that the remaining problems will be overcome within the foreseeable future, and clinical allotransplantation will eventually become of historical interest only.
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Affiliation(s)
- David K C Cooper
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, BST W1543, 200 Lothrop Street, Pittsburgh, PA 15261, USA.
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Diswall M, Angström J, Karlsson H, Phelps CJ, Ayares D, Teneberg S, Breimer ME. Structural characterization of alpha1,3-galactosyltransferase knockout pig heart and kidney glycolipids and their reactivity with human and baboon antibodies. Xenotransplantation 2010; 17:48-60. [PMID: 20149188 DOI: 10.1111/j.1399-3089.2009.00564.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND alpha1,3-galactosyltranferase knockout (GalT-KO) pigs have been established to avoid hyperacute rejection in GalT-KO pig-to-human xenotransplantation. GalT-KO pig heart and kidney glycolipids were studied focusing on elimination of Gal-antigens and whether novel antigens would appear. Non-human primates are used as pre-clinical transplantation experimental models. Therefore, sera from baboons transplanted with GalT-KO hearts were compared with human serum regarding reactivity with pig glycolipids. METHODS Neutral and acidic glycolipids were isolated from GalT-KO and WT pig hearts and kidneys. Glycolipid immune reactivity was tested on TLC plates using human affinity-purified anti-Gal Ig, anti-blood group monoclonal antibodies, lectins, and human serum as well as baboon serum collected before and after GalT-KO pig heart transplantations. Selected glycolipid fractions, isolated by HPLC, were structurally characterized by mass spectrometry and proton NMR spectroscopy. RESULTS GalT-KO heart and kidney lacked alpha3Gal-terminated glycolipids completely. Levels of uncapped N-acetyllactosamine precursor compounds, blood group H type 2 core chain compounds, the P1 antigen and the x(2) antigen were increased. Human serum antibodies reacted with Gal-antigens and N-glycolylneuraminic acid (NeuGc) in WT organs of which only the NeuGc reactivity remained in the GalT-KO tissues. A clear difference in reactivity between baboon and human antibodies with pig glycolipids was found. This was most pronounced for acidic, not yet identified, compounds in GalT-KO organs which were less abundant or lacking in the corresponding WT tissues. CONCLUSIONS GalT-KO pig heart and kidney completely lacked Gal glycolipid antigens whilst glycolipids synthesized by competing pathways were increased. Baboon and human serum antibodies showed a different reactivity pattern to pig glycolipid antigens indicating that non-human primates have limitations as a human pre-clinical model for immune rejection studies.
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Affiliation(s)
- Mette Diswall
- Department of Surgery, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
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Crikis S, Zhang XM, Dezfouli S, Dwyer KM, Murray-Segal LM, Salvaris E, Selan C, Robson SC, Nandurkar HH, Cowan PJ, d’Apice AJF. Anti-inflammatory and anticoagulant effects of transgenic expression of human thrombomodulin in mice. Am J Transplant 2010; 10:242-50. [PMID: 20055798 PMCID: PMC5472991 DOI: 10.1111/j.1600-6143.2009.02939.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Thrombomodulin (TBM) is an important vascular anticoagulant that has species specific effects. When expressed as a transgene in pigs, human (h)TBM might abrogate thrombotic manifestations of acute vascular rejection (AVR) that occur when GalT-KO and/or complement regulator transgenic pig organs are transplanted to primates. hTBM transgenic mice were generated and characterized to determine whether this approach might show benefit without the development of deleterious hemorrhagic phenotypes. hTBM mice are viable and are not subject to spontaneous hemorrhage, although they have a prolonged bleeding time. They are resistant to intravenous collagen-induced pulmonary thromboembolism, stasis-induced venous thrombosis and pulmonary embolism. Cardiac grafts from hTBM mice to rats treated with cyclosporine in a model of AVR have prolonged survival compared to controls. hTBM reduced the inflammatory reaction in the vein wall in the stasis-induced thrombosis and mouse-to-rat xenograft models and reduced HMGB1 levels in LPS-treated mice. These results indicate that transgenic expression of hTBM has anticoagulant and antiinflammatory effects that are graft-protective in murine models.
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Affiliation(s)
- S. Crikis
- Immunology Research Centre, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia,Department of Medicine, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia
| | - X. M. Zhang
- Immunology Research Centre, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia
| | - S. Dezfouli
- Immunology Research Centre, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia
| | - K. M. Dwyer
- Immunology Research Centre, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia,Department of Medicine, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia
| | - L. M. Murray-Segal
- Immunology Research Centre, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia
| | - E. Salvaris
- Immunology Research Centre, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia
| | - C. Selan
- Immunology Research Centre, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia
| | - S. C. Robson
- Liver Center, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - H. H. Nandurkar
- Immunology Research Centre, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia,Department of Medicine, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia
| | - P. J. Cowan
- Immunology Research Centre, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia,Department of Medicine, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia
| | - A. J. F. d’Apice
- Immunology Research Centre, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia,Department of Medicine, The University of Melbourne, St. Vincent’s Hospital, Fitzroy, Vic. 3065, Australia,Corresponding author: Professor Anthony J. F. d’Apice,
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Kim HI, Yu JE, Lee SY, Sul AY, Jang MS, Rashid MA, Park SG, Kim SJ, Park CG, Kim JH, Park KS. The effect of composite pig islet-human endothelial cell grafts on the instant blood-mediated inflammatory reaction. Cell Transplant 2009; 18:31-7. [PMID: 19476207 DOI: 10.3727/096368909788237113] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Instant blood-mediated inflammatory reaction (IBMIR) causes rapid islet loss in portal vein islet transplantation. Endothelial cells are known to protect against complement-mediated lysis and activation of coagulation. We tested composite pig islet-human endothelial cell grafts as a strategy to overcome IBMIR. Porcine islets were cocultured with human endothelial cells in specially modified culture medium composed of M199 and M200 for 1-9 days. A positive control group, negative control group, and the endothelial cell-coated group were examined with an in vitro tubing loop assay using human blood. The endothelial cell-coated group was subdivided and analyzed by degree of surface coverage by endothelial cells (< or = 50% vs. > 50%) or coculture time (< 5 days vs. > or = 5 days). Platelet consumption and complement and coagulation activation were assessed by platelet count, C3a, and thrombin-antithrombin complex (TAT), respectively. After 60-min incubation in human blood, the endothelial cell-coated group showed platelet consumption inhibition and low C3a and TAT assay results compared to uncoated controls. When the endothelial cell-coated group was subdivided by degree of surface coverage, the < or = 50% coated group showed less platelet consumption and less activation of complement and coagulation compared with the positive control (uncoated) group. On analysis by coculture time, only the subgroup cocultured for < 5 days showed the same protective effect. Human endothelial cell-coated pig islets, especially the partially coated and short-term cocultured pig islet-human endothelial cell composites, reduced all components of IBMIR. If the optimal endothelial cell-islet coculture method could be identified, human endothelial cell coating of pig islets would offer new strategies to improve xenogenic islet transplantation outcomes.
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Affiliation(s)
- Hyoung-Il Kim
- Xenotransplantation Research Center, Seoul 110-744, Republic of Korea
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Abstract
PURPOSE OF REVIEW To review the latest development in cardiac xenotransplantation in small and large animal models and related in-vitro studies. RECENT FINDINGS With the recent introduction of alpha1,3-galactosyltransferase gene-knockout (GT-KO) pig organs for xenotransplantation, improved cardiac graft survival has been obtained. However, this experience has demonstrated the importance of pig antigens other than Galalpha1,3Gal (Gal) antigens (so-called nonGal antigens) as targets for primate anti-pig antibodies. Several in-vitro studies have confirmed that, although the incidence and levels of anti-nonGal antibodies in nonhuman primates and humans are significantly less when compared with total anti-pig antibodies (i.e., anti-Gal + anti-nonGal), they can result in complement-mediated lysis of GT-KO pig cells. More recently, it has been demonstrated that regulatory T cells suppress the cellular xenogeneic response, thus potentially preventing or reducing T-cell-mediated rejection. The importance of thrombotic microangiopathy as a feature of the immune/inflammatory response and incompatibilities between the coagulation-anticoagulation systems of pig and primate are receiving increasing attention. Development of GT-KO pigs transgenic for one or more 'antithrombotic' genes, for example, CD39 or tissue factor pathway inhibitor, may contribute to overcoming these problems. SUMMARY Although GT-KO pigs have provided an advance over wild-type pigs as a source of organs for transplantation into primates, further genetic modification of GT-KO pigs is required to overcome the remaining immune barriers before a clinical trial of cardiac xenotransplantation can be contemplated.
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Cowan PJ, d'Apice AJF. Complement activation and coagulation in xenotransplantation. Immunol Cell Biol 2009; 87:203-8. [DOI: 10.1038/icb.2008.107] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Peter J Cowan
- Immunology Research Centre, St Vincent's Hospital Melbourne Melbourne Victoria Australia
- Department of Medicine, University of Melbourne Melbourne Victoria Australia
| | - Anthony JF d'Apice
- Immunology Research Centre, St Vincent's Hospital Melbourne Melbourne Victoria Australia
- Department of Medicine, University of Melbourne Melbourne Victoria Australia
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Park CG, Kim JS, Shin JS, Kim YH, Kim SJ. Current Status and Future Perspectives of Xenotransplantation. ACTA ACUST UNITED AC 2009. [DOI: 10.4285/jkstn.2009.23.3.203] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Chung-Gyu Park
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Korea
- Xenotransplantation Research Center, Seoul National University College of Medicine, Seoul, Korea
- Transplantation Research Institute SNUMRC, Seoul National University College of Medicine, Seoul, Korea
- Cancer Research Institute and TIMRC, Seoul National University College of Medicine, Seoul, Korea
| | - Jung-Sik Kim
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Korea
- Xenotransplantation Research Center, Seoul National University College of Medicine, Seoul, Korea
- Transplantation Research Institute SNUMRC, Seoul National University College of Medicine, Seoul, Korea
- Cancer Research Institute and TIMRC, Seoul National University College of Medicine, Seoul, Korea
| | - Jun-Seop Shin
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Korea
- Xenotransplantation Research Center, Seoul National University College of Medicine, Seoul, Korea
- Transplantation Research Institute SNUMRC, Seoul National University College of Medicine, Seoul, Korea
- Cancer Research Institute and TIMRC, Seoul National University College of Medicine, Seoul, Korea
| | - Yong-Hee Kim
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Korea
- Xenotransplantation Research Center, Seoul National University College of Medicine, Seoul, Korea
- Transplantation Research Institute SNUMRC, Seoul National University College of Medicine, Seoul, Korea
- Cancer Research Institute and TIMRC, Seoul National University College of Medicine, Seoul, Korea
| | - Sang-Joon Kim
- Xenotransplantation Research Center, Seoul National University College of Medicine, Seoul, Korea
- Department of Surgery, Seoul National University College of Medicine, Seoul, Korea
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Affiliation(s)
- Hwajung Kim
- Transplantation Research Institute, Seoul National University Medical Research Center, Seoul, Korea
| | - Jaeseog Yang
- Transplantation Center Seoul National, University Hospital, Transplantation Research Institute, Seoul National University Medical Research Center, Seoul, Korea
| | - Curie Ahn
- Division of Nephrology, Transplantation Research Institute, Seoul National University Medical Research Center, Seoul, Korea
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Abstract
In this review, we summarize the work published over the last 2 years using genetic modifications of animals in the field of xenotransplantation. Genetic engineering of the donor has become a powerful tool in xenotransplantation, both for the inactivation of one particular porcine gene and for the addition of human genes with the goal of overcoming xenogeneic barriers. We summarize the work relative to the knockout of the alpha1,3-galactosyltransferase gene, followed by genetic engineering aimed at reducing the humoral and cellular immune response, complement activation and coagulation. Finally, we report on the genetic modification of pigs to reduce porcine endogenous retrovirus infection risk in the xenogeneic context.
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Lin CC, Cooper DKC, Dorling A. Coagulation dysregulation as a barrier to xenotransplantation in the primate. Transpl Immunol 2008; 21:75-80. [PMID: 19000927 DOI: 10.1016/j.trim.2008.10.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2008] [Accepted: 10/09/2008] [Indexed: 11/28/2022]
Abstract
PURPOSE OF REVIEW The ability to generate pigs expressing a human complement regulatory protein (hCRP) and/or pigs in which the alpha1,3-galactosyltransferase gene has been knocked out (GT-KO) has largely overcome the barrier of hyperacute rejection of a pig organ transplanted into a primate. However, acute humoral xenograft rejection (AHXR), presenting as microvascular thrombosis and/or consumptive coagulopathy, remains a major hurdle to successful xenotransplantation. This review summarizes recent studies of the coagulation problems associated with xenotransplantation, and discusses potential strategies to overcome them. RECENT PROGRESS Organ transplantation into nonhuman primates from GT-KO pigs that express a hCRP are not susceptible to hyperacute rejection. Nevertheless, most recipients of GT-KO and/or hCRP transgenic pig organs develop a consumptive coagulopathy, even when the graft remains functioning. This is associated with platelet aggregation, thrombocytopenia, anemia, and a tendency to bleed. Whilst this may reflect an ongoing immune response against the graft, (as exposure to anti-nonGal antibodies in vitro induces procoagulant changes in porcine ECs, even in the absence of complement), histological examination of the graft often shows only minimal features of immune injury, unlike grafts undergoing typical AHXR. Importantly, recent in vitro studies have indicated that the coincubation of porcine endothelial cells (ECs) with human platelets activates the platelets to express tissue factor, independent of a humoral immune response. These observations suggest that the use of organs from GT-KO pigs that express a hCRP may not be sufficient to prevent the development of a coagulation disorder following xenotransplantation, even if complete immunological tolerance can be achieved. SUMMARY Both thrombotic microangiopathy and systemic consumptive coagulopathy are increasingly recognized as barriers to successful xenotransplantation. The breeding of transgenic pigs with one or more human anticoagulant genes, such as CD39 or tissue factor pathway inhibitor, is anticipated to inhibit the procoagulant changes that take place on the graft ECs, and thus may prevent or reduce platelet activation that arises as a result of immune-mediated injury. The identification of the molecular mechanisms that develop between porcine ECs and human platelets may allow pharmacological approaches to be determined that inhibit the development of thrombotic microangiopathy and consumptive coagulopathy. Hopefully, further genetic modification of the organ-source pigs, combined with systemic drug therapy to the recipient, will prolong graft survival further.
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Affiliation(s)
- Chih Che Lin
- Department of Immunology, Imperial College London, Hammersmith Hospital, London, UK
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The coagulation barrier in xenotransplantation: incompatibilities and strategies to overcome them. Curr Opin Organ Transplant 2008; 13:178-83. [PMID: 18685300 DOI: 10.1097/mot.0b013e3282f63c74] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Dysregulated coagulation is now recognized as a major contributor to graft loss in xenotransplantation. This review summarizes recent data on putative mechanisms of pathogenic coagulation in xenotransplantation and discusses progress on strategies to overcome them. RECENT FINDINGS Evidence continues to grow that the primary cause of failure of pig cardiac and renal xenografts is probably antibody-mediated injury to the endothelium, leading to development of microvascular thrombosis. Several factors that may exacerbate the problem will remain, even in the absence of a humoral response. These include molecular incompatibilities that affect the control of coagulation - in particular the failure of pig thrombomodulin to activate the primate protein C pathway - and platelet reactivity. Expression of anticoagulant and antiplatelet molecules within the graft is a potential solution that has been successfully tested in rodent models and will soon be applied to the pig-to-primate model. This strategy, in parallel with physical methods such as encasing islets in a protective layer, also holds promise for reducing the thrombogenicity of pig islet xenografts. SUMMARY Thrombosis is a barrier to long-term survival and function of porcine xenografts, which may eventually be overcome by various combinations of genetic and physical manipulation.
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Saethre M, Schneider MKJ, Lambris JD, Magotti P, Haraldsen G, Seebach JD, Mollnes TE. Cytokine secretion depends on Galalpha(1,3)Gal expression in a pig-to-human whole blood model. THE JOURNAL OF IMMUNOLOGY 2008; 180:6346-53. [PMID: 18424758 DOI: 10.4049/jimmunol.180.9.6346] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Transplants from alpha1,3-galactosyltransferase (Gal) gene-knockout pigs to nonhuman primates are largely protected from hyperacute but not acute humoral xenograft rejection. The present study investigates the role of Gal in cytokine responses using a novel pig-to-human whole blood in vitro model, developed for species-specific analysis of porcine and human cytokines. Porcine (n = 7) and human (n = 27) cytokines were measured using ELISA or multiplex technology, respectively. Porcine aortic endothelial cells from control (Gal(+/+)) and Gal-deficient (Gal(-/-)) pigs were incubated with human lepirudin anticoagulated whole blood from healthy donors. E-selectin expression was measured by flow cytometry. The C3 inhibitor compstatin and a C5aR antagonist were used to study the role of complement. Cytokine species specificity was documented, enabling detection of 2 of 7 porcine cytokines and 13 of 27 human cytokines in one single sample. Gal(+/+) porcine aortic endothelial cells incubated with human whole blood showed a marked complement C5b-9 dependent up-regulation of E-selectin and secretion of porcine IL-6 and IL-8. In contrast, Gal(-/-) cells responded with E-selectin and cytokine expression which was so weak that the role of complement could not be determined. Human IL-6, IL-8, IFN-gamma, MIP-1alpha, MIP-1beta, eotaxin, and RANTES were detected in the Gal(+/+) system, but virtually no responses were seen in the Gal(-/-) system (p = 0.03). The increase in human cytokine release was largely complement dependent and, in contrast to the porcine response, mediated through C5a. Species-specific analysis of cytokine release revealed a marked, complement-dependent response when Gal(+/+) pig cells were incubated with human whole blood, compared with Gal(-/-) cells which induced virtually no cytokine release.
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Affiliation(s)
- Marit Saethre
- Institute of Immunology, Rikshospitalet University Hospital and Faculty of Medicine, University of Oslo, Oslo, Norway
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González Martín M, García Buitrón J, Alonso Hernández A, Cortés Centeno A, López Peláez E, Vázquez Martul E, Mosquera Reboredo J, Requejo Isidro I, Máńez Mendiluce R. [Renal xenotransplant. Acute vascular rejection]. Actas Urol Esp 2008; 32:152-9. [PMID: 18411633 DOI: 10.1016/s0210-4806(08)73805-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
INTRODUCTION AND OBJECTIVES Organ transplant is nowadays a usual and succesful practice, although with limited application due to the lack of organs. Yearly thousands of patients get access to the waiting list and finally will death while they are waiting for an organ. In the U.S.A., 2005 waiting list for kidneys, heart, liver lung and pancreas was around 94.419. Number of transplants performed was 27.966 and died patients while waiting for an organ, 41.392 (1). Pig xenotransplant is one of the possibilities to ameliorate the lack of organs for transplant. Arrangement of pigs with different genetic modifications generated great expectatives on the use of these organs in clinics. Although preclinical experimental studies with kidneys reached prolonged survivals, these are really insufficient to go on with the clinical appliance. Hyperacute rejection produces destruction of the organ immediately. This problem could be pharmacologically precluded in xeno-transplant. However, acute rejection or vascular rejection usually produces the lost of the implant. New inmunosuppresive schedules delay significantly rejection, but not definitively. Xenotransplant as a therapeutic option introduces important scientific problems, as well as ethical and social. This paper reports a summary of our experience in renal xenotransplant and the management of acute rejection. MATERIAL AND METHODS Twenty xenotransplants from transgenic pig (hDAF) as donor to babuine as receptor. Average weight of the animals ranged 11.4-75 kgrs and babuines 10-26 kg. Xenograft average weight ranged 39-160 grs. Implant was performed to aorta and cava. Four inmunosupressive schedules were used. RESULTS Average survival was 7-9 days. Final Histological findings are described. Changes observed were secondary to acute tubular necrosis mixed with changes due to acute rejection. Three grafts were lost due to technical major problems. CONCLUSIONS Although we have observed some promising results, xenotransplant is a very difficult problem to solve in the long-term. A lot of research is still needed-.
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Affiliation(s)
- M González Martín
- Servicio de Urologia, Hospital Universitario Juan Canalejo-Fundación Barrié de la Maza, La Coruña, España.
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Abstract
Xenotransplantation holds promise to solve the ever increasing shortage of donor organs for allotransplantation. In the last 2 decades, major progress has been made in understanding the immunobiology of pig-into-(non)human primate transplantation and today we are on the threshold of the first clinical trials. Hyperacute rejection, which is mediated by pre-existing anti-alpha Gal xenoreactive antibodies, can in non-human primates be overcome by complement- and/or antibody-modifying interventions. A major step forward was the development of genetically engineered pigs, either transgenic for human complement regulatory proteins or deficient in the alpha1,3-galactosyltranferase enzyme. However, several other immunologic and nonimmunologic hurdles remain. Acute vascular xenograft rejection is mediated by humoral and cellular mechanisms. Elicited xenoreactive antibodies play a key role. In addition to providing B cell help, xenoreactive T cells may directly contribute to xenograft rejection. Long-term survival of porcine kidney- and heart xenografts in non-human primates has been obtained but required severe T and B cell immunosuppression. Induction of xenotolerance, e.g. through mixed hematopoietic chimerism, may represent the preferred approach, but although proof of principle has been delivered in rodents, induction of pig-to-non-human primate chimerism remains problematic. Finally, it is now clear that innate immune cells, in particular macrophages and natural killer cells, can mediate xenograft destruction, the determinants of which are being elucidated. Chronic xenograft rejection is not well understood, but recent studies indicate that non-immunological problems, such as incompatibilities between human procoagulant and pig anticoagulant components may play an important role. Here, we give a comprehensive overview of the currently known obstacles to xenografting: immune and non-immune problems are discussed, as well as the possible strategies that are under development to overcome these hurdles.
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Affiliation(s)
- B Sprangers
- Laboratory of Experimental Transplantation, University of Leuven, Leuven, Belgium
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Reduced Fibrin Deposition and Intravascular Thrombosis in hDAF Transgenic Pig Hearts Perfused With Tirofiban. Transplantation 2007; 84:1667-76. [DOI: 10.1097/01.tp.0000295742.45413.dc] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Porter CM, Horvath-Arcidiacono JA, Singh AK, Horvath KA, Bloom ET, Mohiuddin MM. Characterization and expansion of baboon CD4+CD25+ Treg cells for potential use in a non-human primate xenotransplantation model. Xenotransplantation 2007; 14:298-308. [PMID: 17669171 DOI: 10.1111/j.1399-3089.2007.00416.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND It is well established that CD4(+)CD25(+) regulatory T (Treg) cells can modulate allogeneic immune responses. Xenotransplantation, proposed as a means to address the critical shortage of human organs, may also benefit from similar approaches to avert rejection. Baboons are a preferred preclinical animal model for xenogeneic organ transplantation experiments, and the characterization of baboon Treg cells will be beneficial to future tolerance studies in this animal model. METHODS We analyzed CD4(+)CD25(+) T cells from baboon lymph nodes, spleens, and blood by flow cytometry, then purified and expanded porcine antigen-specific baboon CD4(+)CD25(high) cells in vitro to evaluate their regulatory activity in the baboon anti-pig xenogeneic responses. RESULTS CD4(+)CD25(high) T cells were 1.7%, 3.1%, and 1.9% of baboon splenic, lymph node, and blood T cells, respectively. The CD4(+)CD25(high) T cells expressed the Treg cell-associated transcription factor, FoxP3. Proliferation/suppression assays using irradiated pig peripheral blood mononuclear cells as stimulators showed that Treg cells suppressed the vigorous baboon CD4(+)CD25(-) T-cell anti-pig proliferation response and cytokine secretion. Expanded baboon Treg cells suppressed baboon anti-pig CD4(+)CD25(-) T-cell proliferation approximately 4- to 10-fold more than freshly isolated Treg cells. Expanded Treg cells suppressed proliferation to primary cells from the same pig used for expansion more effectively than proliferation to stimulators from a different strain of pig, suggesting a level of antigen specificity. CONCLUSION We demonstrate that baboon Treg cells suppress immune responses to xenogeneic stimulation. These studies suggest that adoptive transfer of expanded Treg cells into transplant recipients may provide an approach to prevent cell-mediated rejection of grafts and potentially induce tolerance in the pig to baboon xenotransplantation preclinical model.
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Affiliation(s)
- Cynthia M Porter
- Division of Cellular and Gene Therapy, CBER, FDA, Bethesda, Mayland 20892, USA.
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39
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Baertschiger RM, Buhler LH. Xenotransplantation literature update January-February, 2007. Xenotransplantation 2007; 14:273-7. [PMID: 17489870 DOI: 10.1111/j.1399-3089.2007.00397.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Reto M Baertschiger
- Surgical Research Unit, Department of Surgery, University Hospital Geneva, Geneva, Switzerland
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