1
|
Xu J, Ren J, Xu K, Fang M, Ka M, Xu F, Wang X, Wang J, Han Z, Feng G, Zhang Y, Hai T, Li W, Hu Z. Elimination of GGTA1, CMAH, β4GalNT2 and CIITA genes in pigs compromises human versus pig xenogeneic immune reactions. Animal Model Exp Med 2024. [PMID: 38962826 DOI: 10.1002/ame2.12461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Accepted: 06/13/2024] [Indexed: 07/05/2024] Open
Abstract
BACKGROUND Pig organ xenotransplantation is a potential solution for the severe organ shortage in clinic, while immunogenic genes need to be eliminated to improve the immune compatibility between humans and pigs. Current knockout strategies are mainly aimed at the genes causing hyperacute immune rejection (HAR) that occurs in the first few hours while adaptive immune reactions orchestrated by CD4 T cell thereafter also cause graft failure, in which process the MHC II molecule plays critical roles. METHODS Thus, we generate a 4-gene (GGTA1, CMAH, β4GalNT2, and CIITA) knockout pig by CRISPR/Cas9 and somatic cell nuclear transfer to compromise HAR and CD4 T cell reactions simultaneously. RESULTS We successfully obtained 4KO piglets with deficiency in all alleles of genes, and at cellular and tissue levels. Additionally, the safety of our animals after gene editing was verified by using whole-genome sequencing and karyotyping. Piglets have survived for more than one year in the barrier, and also survived for more than 3 months in the conventional environment, suggesting that the piglets without MHC II can be raised in the barrier and then gradually mated in the conventional environment. CONCLUSIONS 4KO piglets have lower immunogenicity, are safe in genomic level, and are easier to breed than the model with both MHC I and II deletion.
Collapse
Affiliation(s)
- Jing Xu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Organ Regeneration and Reconstruction, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jilong Ren
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Organ Regeneration and Reconstruction, Chinese Academy of Sciences, Beijing, China
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
| | - Kai Xu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Organ Regeneration and Reconstruction, Chinese Academy of Sciences, Beijing, China
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
| | - Minghui Fang
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital, Jilin University, Changchun, China
| | - Meina Ka
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Organ Regeneration and Reconstruction, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Fei Xu
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital, Jilin University, Changchun, China
| | - Xin Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Organ Regeneration and Reconstruction, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jing Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Organ Regeneration and Reconstruction, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Zhiqiang Han
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Organ Regeneration and Reconstruction, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Guihai Feng
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Organ Regeneration and Reconstruction, Chinese Academy of Sciences, Beijing, China
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
| | - Ying Zhang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Organ Regeneration and Reconstruction, Chinese Academy of Sciences, Beijing, China
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
| | - Tang Hai
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Organ Regeneration and Reconstruction, Chinese Academy of Sciences, Beijing, China
- Beijing Farm Animal Research Center, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Wei Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Organ Regeneration and Reconstruction, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
| | - Zheng Hu
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital, Jilin University, Changchun, China
| |
Collapse
|
2
|
Schmoeckel M, Längin M, Reichart B, Abicht JM, Bender M, Michel S, Kamla CE, Denner J, Tönjes RR, Schwinzer R, Marckmann G, Wolf E, Brenner P, Hagl C. Current Status of Cardiac Xenotransplantation: Report of a Workshop of the German Heart Transplant Centers, Martinsried, March 3, 2023. Thorac Cardiovasc Surg 2024; 72:273-284. [PMID: 38154473 PMCID: PMC11147670 DOI: 10.1055/a-2235-8854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 11/22/2023] [Indexed: 12/30/2023]
Abstract
This report comprises the contents of the presentations and following discussions of a workshop of the German Heart Transplant Centers in Martinsried, Germany on cardiac xenotransplantation. The production and current availability of genetically modified donor pigs, preservation techniques during organ harvesting, and immunosuppressive regimens in the recipient are described. Selection criteria for suitable patients and possible solutions to the problem of overgrowth of the xenotransplant are discussed. Obviously microbiological safety for the recipient and close contacts is essential, and ethical considerations to gain public acceptance for clinical applications are addressed. The first clinical trial will be regulated and supervised by the Paul-Ehrlich-Institute as the National Competent Authority for Germany, and the German Heart Transplant Centers agreed to cooperatively select the first patients for cardiac xenotransplantation.
Collapse
Affiliation(s)
- Michael Schmoeckel
- Herzchirurgische Klinik und Poliklinik, LMU Klinikum, LMU München, Germany
| | - Matthias Längin
- Klinik für Anaesthesiologie, LMU Klinikum, LMU München, Germany
- DFG-Transregio-Sonderforschungsbereich TR127—Xenotransplantation, Walter-Brendel-Zentrum für Experimentelle Medizin, LMU München, Germany
| | - Bruno Reichart
- DFG-Transregio-Sonderforschungsbereich TR127—Xenotransplantation, Walter-Brendel-Zentrum für Experimentelle Medizin, LMU München, Germany
| | - Jan-Michael Abicht
- Klinik für Anaesthesiologie, LMU Klinikum, LMU München, Germany
- DFG-Transregio-Sonderforschungsbereich TR127—Xenotransplantation, Walter-Brendel-Zentrum für Experimentelle Medizin, LMU München, Germany
| | - Martin Bender
- Klinik für Anaesthesiologie, LMU Klinikum, LMU München, Germany
- DFG-Transregio-Sonderforschungsbereich TR127—Xenotransplantation, Walter-Brendel-Zentrum für Experimentelle Medizin, LMU München, Germany
| | - Sebastian Michel
- Herzchirurgische Klinik und Poliklinik, LMU Klinikum, LMU München, Germany
- DFG-Transregio-Sonderforschungsbereich TR127—Xenotransplantation, Walter-Brendel-Zentrum für Experimentelle Medizin, LMU München, Germany
| | | | - Joachim Denner
- DFG-Transregio-Sonderforschungsbereich TR127—Xenotransplantation, Walter-Brendel-Zentrum für Experimentelle Medizin, LMU München, Germany
- Institut für Virologie, Fachbereich für Veterinärmedizin, Freie Universität Berlin, Berlin, Germany
| | - Ralf Reinhard Tönjes
- DFG-Transregio-Sonderforschungsbereich TR127—Xenotransplantation, Walter-Brendel-Zentrum für Experimentelle Medizin, LMU München, Germany
- Paul-Ehrlich-Institut, Langen, Germany
| | - Reinhard Schwinzer
- DFG-Transregio-Sonderforschungsbereich TR127—Xenotransplantation, Walter-Brendel-Zentrum für Experimentelle Medizin, LMU München, Germany
- Klinik für Allgemein-, Viszeral- und Transplantationschirurgie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Georg Marckmann
- DFG-Transregio-Sonderforschungsbereich TR127—Xenotransplantation, Walter-Brendel-Zentrum für Experimentelle Medizin, LMU München, Germany
- Institut für Ethik, Geschichte und Theorie der Medizin, LMU München, Germany
| | - Eckhard Wolf
- DFG-Transregio-Sonderforschungsbereich TR127—Xenotransplantation, Walter-Brendel-Zentrum für Experimentelle Medizin, LMU München, Germany
- Lehrstuhl für Molekulare Tierzucht und Biotechnologie, Genzentrum der LMU München, Germany
| | - Paolo Brenner
- Herzchirurgische Klinik und Poliklinik, LMU Klinikum, LMU München, Germany
- DFG-Transregio-Sonderforschungsbereich TR127—Xenotransplantation, Walter-Brendel-Zentrum für Experimentelle Medizin, LMU München, Germany
| | - Christian Hagl
- Herzchirurgische Klinik und Poliklinik, LMU Klinikum, LMU München, Germany
- DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), Partner Site Munich, Germany
| |
Collapse
|
3
|
Vadori M, Cozzi E. Current challenges in xenotransplantation. Curr Opin Organ Transplant 2024; 29:205-211. [PMID: 38529696 PMCID: PMC11064916 DOI: 10.1097/mot.0000000000001146] [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: 03/27/2024]
Abstract
PURPOSE OF REVIEW In recent years, the xenotransplantation science has advanced tremendously, with significant strides in both preclinical and clinical research. This review intends to describe the latest cutting-edge progress in knowledge and methodologies developed to overcome potential obstacles that may preclude the translation and successful application of clinical xenotransplantation. RECENT FINDINGS Preclinical studies have demonstrated that it is now possible to extend beyond two years survival of primate recipients of life saving xenografts. This has been accomplished thanks to the utilization of genetic engineering methodologies that have allowed the generation of specifically designed gene-edited pigs, a careful donor and recipient selection, and appropriate immunosuppressive strategies.In this light, the compassionate use of genetically modified pig hearts has been authorized in two human recipients and xenotransplants have also been achieved in human decedents. Although encouraging the preliminary results suggest that several challenges have yet to be fully addressed for a successful clinical translation of xenotransplantation. These challenges include immunologic, physiologic and biosafety aspects. SUMMARY Recent progress has paved the way for the initial compassionate use of pig organs in humans and sets the scene for a wider application of clinical xenotransplantation.
Collapse
Affiliation(s)
- Marta Vadori
- Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University of Padua
| | - Emanuele Cozzi
- Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University of Padua
- Transplant Immunology Unit, Department of Cardiac, Thoracic, Vascular Sciences and Public Health Padua University Hospital, Padua, Italy
| |
Collapse
|
4
|
Reyes L, Wang ZY, Estrada J, Burlak C, Gennuso VN, Ho S, Tector M, Tector AJ. Non-Classical Swine Leukocyte Antigens SLA-6, -7, and -8, Are Xenoantigens for Some Waitlisted Patients. Xenotransplantation 2024; 31:e12872. [PMID: 38924560 DOI: 10.1111/xen.12872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 05/14/2024] [Accepted: 05/17/2024] [Indexed: 06/28/2024]
Abstract
Attack of donor tissues by pre-formed anti-pig antibodies is well known to cause graft failure in xenotransplantation. Genetic engineering of porcine donors to eliminate targets of these pre-formed antibodies coupled with advances in immunosuppressive medicines have now made it possible to achieve extended survival in the pre-clinical pig-to-non-human primate model. Despite these improvements, antibodies remain a risk over the lifetime of the transplant, and many patients continue to have pre-formed donor-specific antibodies even to highly engineered pigs. While therapeutics exist that can help mitigate the detrimental effects of antibodies, they act broadly potentially dampening beneficial immunity. Identifying additional xenoantigens may enable more targeted approaches, such as gene editing, to overcome these challenges by further eliminating antibody targets on donor tissue. Because we have found that classical class I swine leukocyte antigens are targets of human antibodies, we now examine whether related pig proteins may also be targeted by human antibodies. We show here that non-classical class I swine leukocyte proteins (SLA-6, -7, -8) can be expressed at the surface of mammalian cells and act as antibody targets.
Collapse
Affiliation(s)
- Luz Reyes
- Department of Surgery, University of Miami School of Medicine, Miami, Florida, USA
| | - Zheng-Yu Wang
- Department of Surgery, University of Miami School of Medicine, Miami, Florida, USA
| | - Jose Estrada
- Department of Surgery, University of Miami School of Medicine, Miami, Florida, USA
| | - Christopher Burlak
- Department of Surgery, University of Miami School of Medicine, Miami, Florida, USA
| | | | - Sam Ho
- Gift of Hope Organ and Tissue Donor Network, Itasca, Illinois, USA
| | | | - Alfred Joseph Tector
- Department of Surgery, University of Miami School of Medicine, Miami, Florida, USA
| |
Collapse
|
5
|
Ladowski JM, Tector M, Martens G, Wang ZY, Burlak C, Reyes L, Estrada J, Adams A, Tector AJ. Late graft failure of pig-to-rhesus renal xenografts has features of glomerulopathy and recipients have anti-swine leukocyte antigen class I and class II antibodies. Xenotransplantation 2024; 31:e12862. [PMID: 38761019 PMCID: PMC11104517 DOI: 10.1111/xen.12862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 03/12/2024] [Accepted: 04/30/2024] [Indexed: 05/20/2024]
Abstract
Prolonged survival in preclinical renal xenotransplantation demonstrates that early antibody mediated rejection (AMR) can be overcome. It is now critical to evaluate and understand the pathobiology of late graft failure and devise new means to improve post xenograft outcomes. In renal allotransplantation the most common cause of late renal graft failure is transplant glomerulopathy-largely due to anti-donor MHC antibodies, particularly anti-HLA DQ antibodies. We evaluated the pig renal xenograft pathology of four long-surviving (>300 days) rhesus monkeys. We also evaluated the terminal serum for the presence of anti-SLA class I and specifically anti-SLA DQ antibodies. All four recipients had transplant glomerulopathy and expressed anti-SLA DQ antibodies. In one recipient tested for anti-SLA I antibodies, the recipient had antibodies specifically reacting with two of three SLA I alleles tested. These results suggest that similar to allotransplantation, anti-MHC antibodies, particularly anti-SLA DQ, may be a barrier to improved long-term xenograft outcomes.
Collapse
Affiliation(s)
| | | | - Gregory Martens
- Department of Surgery, Washington University School of Medicine, St. Louis MO
| | - Zheng Yu Wang
- Department of Surgery, University of Miami School of Medicine, Miami, FL
| | - Chris Burlak
- Department of Surgery, University of Miami School of Medicine, Miami, FL
| | - Luz Reyes
- Department of Surgery, University of Miami School of Medicine, Miami, FL
| | - Jose Estrada
- Department of Surgery, University of Miami School of Medicine, Miami, FL
| | - Andrew Adams
- Department of Surgery, University of Minnesota School of Medicine, Minneapolis, MN
| | - A. Joseph Tector
- Department of Surgery, University of Miami School of Medicine, Miami, FL
| |
Collapse
|
6
|
Byrne GW, McGregor CGA. Anti-pig antibodies in swine veterinarian serum: Implications for clinical xenotransplantation. Xenotransplantation 2024; 31:e12865. [PMID: 38853364 DOI: 10.1111/xen.12865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 05/06/2024] [Accepted: 05/14/2024] [Indexed: 06/11/2024]
Abstract
Recent clinical xenotransplantation and human decedent studies demonstrate that clinical hyperacute rejection of genetically engineered porcine organs can be reliably avoided but that antibody mediated rejection (AMR) continues to limit graft survival. We previously identified porcine glycans and proteins which are immunogenic after cardiac xenotransplantation in non-human primates, but the clinical immune response to antigens present in glycan depleted triple knockout (TKO) donor pigs is poorly understood. In this study we use fluorescence barcoded human embryonic kidney cells (HEK) and HEK cell lines expressing porcine glycans (Gal and SDa) or proteins (tetraspanin-29 [CD9], membrane cofactor protein [CD46], protectin, membrane attack complex inhibition factor [CD59], endothelial cell protein C receptor, and Annexin A2) to screen antibody reactivity in human serum from 160 swine veterinarians, a serum source with potential occupational immune challenge from porcine tissues and pathogens. High levels of anti-Gal IgM were present in all samples and lower levels of anti-SDa IgM were present in 41% of samples. IgM binding to porcine proteins, primarily CD9 and CD46, previously identified as immunogenic in pig to non-human primate cardiac xenograft recipients, was detected in 28 of the 160 swine veterinarian samples. These results suggest that barcoded HEK cell lines expressing porcine protein antigens can be useful for screening human patient serum. A comprehensive analysis of sera from clinical xenotransplant recipients to define a panel of commonly immunogenic porcine antigens will likely be necessary to establish an array of porcine non-Gal antigens for effective monitoring of patient immune responses and allow earlier therapies to reverse AMR.
Collapse
Affiliation(s)
- Guerard W Byrne
- Twin Cities, Department of Surgery, Experimental Surgical Services, University of Minnesota, Minneapolis, Minnesota, USA
- Institute of Cardiovascular Sciences, University College London, London, UK
| | - Christopher G A McGregor
- Twin Cities, Department of Surgery, Experimental Surgical Services, University of Minnesota, Minneapolis, Minnesota, USA
- Institute of Cardiovascular Sciences, University College London, London, UK
| |
Collapse
|
7
|
Raza SS, Hara H, Eyestone W, Ayares D, Cleveland DC, Cooper DKC. Pigs in Transplantation Research and Their Potential as Sources of Organs in Clinical Xenotransplantation. Comp Med 2024; 74:33-48. [PMID: 38359908 PMCID: PMC11078278 DOI: 10.30802/aalas-cm-23-000030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/20/2023] [Accepted: 10/29/2023] [Indexed: 02/17/2024]
Abstract
The pig has long been used as a research animal and has now gained importance as a potential source of organs for clinical xenotransplantation. When an organ from a wild-type (i. e., genetically unmodified) pig is transplanted into an immunosuppressed nonhuman primate, a vigorous host immune response causes hyperacute rejection (within minutes or hours). This response has been largely overcome by 1) extensive gene editing of the organ-source pig and 2) the administration to the recipient of novel immunosuppressive therapy based on blockade of the CD40/CD154 T cell costimulation pathway. Gene editing has consisted of 1) deletion of expression of the 3 known carbohydrate xenoantigens against which humans have natural (preformed) antibodies and 2) the introduction of human 'protective' genes. The combination of gene editing and novel immunosuppressive therapy has extended life-supporting pig kidney graft survival to greater than 1 y and of pig heart survival to up to 9 mo. This review briefly describes the techniques of gene editing, the potential risks of transfer of porcine endogenous retroviruses with the organ, and the need for breeding and housing of donor pigs under biosecure conditions.
Collapse
Key Words
- crp, complement-regulatory protein
- epcr, endothelial protein c receptor
- gal, galactose-α1,3-galactose
- gtko, α1,3-galactosyltransferase gene-knockout
- herv, human endogenous retrovirus
- neu5gc, n-glycolylneuraminic acid
- nhp, nonhuman primates
- perv, porcine endogenous retrovirus
- tko, triple knockout
- wt, wild-type
Collapse
Affiliation(s)
- S Sikandar Raza
- Department of Cardiac Surgery, University of Michigan, Ann Arbor, Michigan
| | - Hidetaka Hara
- College of Veterinary Medicine, Yunnan Agricultural University, Kunming, Yunnan, China
| | | | | | - David C Cleveland
- Department of Cardiothoracic Surgery, Children's Hospital of Los Angeles, Los Angeles, California
| | - David K C Cooper
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts;,
| |
Collapse
|
8
|
He S, Li T, Feng H, Du J, Cooper DKC, Hara H, Jiang H, Pan D, Chen G, Wang Y. Incidence of serum antibodies to xenoantigens on triple-knockout pig cells in different human groups. Xenotransplantation 2024; 31:e12818. [PMID: 37529830 DOI: 10.1111/xen.12818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/02/2023] [Accepted: 07/26/2023] [Indexed: 08/03/2023]
Abstract
BACKGROUND Xenoantigens other than Gal, Neu5Gc, and Sda may be playing a role in pig graft rejection. We investigated the incidence of antibodies to unknown pig xenoantigen in different human groups. METHODS We collected blood from TKO/hCD55 pigs (n = 3), and isolated PBMCs and RBCs. Serum samples were collected from (i) healthy human volunteers (n = 43), (ii) patients with end-stage renal disease (ESRD) (n = 87), (iii) the same patients after kidney allotransplantation (n = 50), and (iv) renal allotransplant recipients experiencing T cell-mediated rejection (allo-TCMR, n = 10). The sera were initially incubated with TKO/hCD55 pRBCs (1 × 108 cells) for 1 h to absorb anti-pig antibodies (except against SLA and possibly other antigens not expressed on pRBCs) and then the serum (absorbed or unabsorbed) was tested for antibody binding and complement-dependent cytotoxicity (CDC) to TKO/hCD55 pig PBMCs. RESULTS A significant reduction in IgM/IgG binding and CDC was observed in the absorbed sera. Serum obtained before and after renal allotransplantation showed no significant difference in IgM or IgG binding to, or in CDC of, TKO/hCD55 pig cells. IgM antibodies (but rarely IgG) against unknown xenoantigens expressed on TKO/hCD55 PBMCs, possibly against swine leukocyte antigens, were documented in healthy humans, patients with ESRD, and those with renal allografts undergoing acute T cell rejection. IgM (but not CDC) was higher in patients experiencing allo-TCMR. CONCLUSION Human sera contain IgM antibodies against unknown pig xenoantigens expressed on TKO/hCD55 pPBMCs. Although not confirmed in the present study, the targets for these antibodies may include swine leukocyte antigens.
Collapse
Affiliation(s)
- Songzhe He
- Department of Kidney Transplantation, the Second Affiliated Hospital of Hainan Medical University, Haikou, China
- The Transplantation Institute of Hainan, Haikou, China
| | - Tao Li
- Department of Kidney Transplantation, the Second Affiliated Hospital of Hainan Medical University, Haikou, China
- The Transplantation Institute of Hainan, Haikou, China
| | - Hao Feng
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Organ Transplantation, Ministry of Education, NHC Key Laboratory of Organ Transplantation, Key Laboratory of Organ Transplantation, Chinese Academy of Medical Sciences, Wuhan, China
| | - Jiaxiang Du
- Chengdu Clonorgan Biotechnology Co., Ltd, Chengdu, China
| | - David K C Cooper
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Hidetaka Hara
- College of Veterinary Medicine, Yunnan Agricultural University, Kunming, Yunnan, China
| | - Hongtao Jiang
- Department of Kidney Transplantation, the Second Affiliated Hospital of Hainan Medical University, Haikou, China
- The Transplantation Institute of Hainan, Haikou, China
| | - Dengke Pan
- Clinical Immunology Translational Medicine Key Laboratory of Sichuan Province, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, China
| | - Gang Chen
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Organ Transplantation, Ministry of Education, NHC Key Laboratory of Organ Transplantation, Key Laboratory of Organ Transplantation, Chinese Academy of Medical Sciences, Wuhan, China
| | - Yi Wang
- Department of Kidney Transplantation, the Second Affiliated Hospital of Hainan Medical University, Haikou, China
- The Transplantation Institute of Hainan, Haikou, China
- Second Affiliated Hospital of University of South China, Hengyang, China
| |
Collapse
|
9
|
Xu H, He X. Developments in kidney xenotransplantation. Front Immunol 2024; 14:1242478. [PMID: 38274798 PMCID: PMC10808336 DOI: 10.3389/fimmu.2023.1242478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 12/13/2023] [Indexed: 01/27/2024] Open
Abstract
The search for kidney xenografts that are appropriate for patients with end-stage renal disease has been ongoing since the beginning of the last century. The major cause of xenograft loss is hyperacute and acute rejection, and this has almost been overcome via scientific progress. The success of two pre-clinical trials of α1,3-galactosyltransferase gene-knockout porcine kidneys in brain-dead patients in 2021 triggered research enthusiasm for kidney xenotransplantation. This minireview summarizes key issues from an immunological perspective: the discovery of key xenoantigens, investigations into key co-stimulatory signal inhibition, gene-editing technology, and immune tolerance induction. Further developments in immunology, particularly immunometabolism, might help promote the long-term outcomes of kidney xenografts.
Collapse
Affiliation(s)
| | - Xiaozhou He
- Urology Department, Third Affiliated Hospital of Soochow University, Changzhou, China
| |
Collapse
|
10
|
Li Z, Liu X, Wang C, Li Z, Jiang B, Zhang R, Tong L, Qu Y, He S, Chen H, Mao Y, Li Q, Pook T, Wu Y, Zan Y, Zhang H, Li L, Wen K, Chen Y. The pig pangenome provides insights into the roles of coding structural variations in genetic diversity and adaptation. Genome Res 2023; 33:1833-1847. [PMID: 37914227 PMCID: PMC10691484 DOI: 10.1101/gr.277638.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 09/12/2023] [Indexed: 11/03/2023]
Abstract
Structural variations have emerged as an important driving force for genome evolution and phenotypic variation in various organisms, yet their contributions to genetic diversity and adaptation in domesticated animals remain largely unknown. Here we constructed a pangenome based on 250 sequenced individuals from 32 pig breeds in Eurasia and systematically characterized coding sequence presence/absence variations (PAVs) within pigs. We identified 308.3-Mb nonreference sequences and 3438 novel genes absent from the current reference genome. Gene PAV analysis showed that 16.8% of the genes in the pangene catalog undergo PAV. A number of newly identified dispensable genes showed close associations with adaptation. For instance, several novel swine leukocyte antigen (SLA) genes discovered in nonreference sequences potentially participate in immune responses to productive and respiratory syndrome virus (PRRSV) infection. We delineated previously unidentified features of the pig mobilome that contained 490,480 transposable element insertion polymorphisms (TIPs) resulting from recent mobilization of 970 TE families, and investigated their population dynamics along with influences on population differentiation and gene expression. In addition, several candidate adaptive TE insertions were detected to be co-opted into genes responsible for responses to hypoxia, skeletal development, regulation of heart contraction, and neuronal cell development, likely contributing to local adaptation of Tibetan wild boars. These findings enhance our understanding on hidden layers of the genetic diversity in pigs and provide novel insights into the role of SVs in the evolutionary adaptation of mammals.
Collapse
Affiliation(s)
- Zhengcao Li
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China;
| | - Xiaohong Liu
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Chen Wang
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Zhenyang Li
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Bo Jiang
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Ruifeng Zhang
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Lu Tong
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Youping Qu
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Sheng He
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Haifan Chen
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Yafei Mao
- Bio-X Institutes, Shanghai Jiao Tong University, 200240 Shanghai, China
| | - Qingnan Li
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Torsten Pook
- Animal Breeding and Genomics, Wageningen University & Research, Wageningen 6700 AH, The Netherlands
| | - Yu Wu
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Yanjun Zan
- Key Laboratory of Tobacco Improvement and Biotechnology, Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266000, China
| | - Hui Zhang
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Lu Li
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Keying Wen
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China
| | - Yaosheng Chen
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006 Guangzhou, China;
| |
Collapse
|
11
|
Cooper DKC, Raza SS, Chaban R, Pierson RN. Shooting for the moon: Genome editing for pig heart xenotransplantation. J Thorac Cardiovasc Surg 2023; 166:973-980. [PMID: 35659123 PMCID: PMC10124774 DOI: 10.1016/j.jtcvs.2022.04.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 04/04/2022] [Accepted: 04/16/2022] [Indexed: 10/18/2022]
Abstract
Gene-edited pigs could eventually provide organs that are safely and effectively protected from the human immune response without exogenous immunosuppression. Genome editing technology has revolutionized heart xenotransplantation and made transplantation of bioengineered pig hearts into humans a possibility. This first clinical application resulted from a tremendous amount of research. Dramatic early attempts of clinical cardiac xenotransplantation during the last century paved the way to modern xenotransplantation using bioengineered pig hearts. It appears that such genome-edited hearts will be most suitable for neonates and infants because of their immature immune system. The bioengineered pig heart may also be used as a bridge to human heart transplantation, avoiding the risk of thromboembolic events of durable ventricular assist devises in these young children. It is also intriguing to think that bioengineered hearts using pigs as a host may result in a new source of donor hearts that would not evoke the human immune response and minimize, if not eliminate, the need for immunosuppression. It this issue of the Journal, a group of experts led by Dr Cooper, whose personal work spans over 50 years of heart transplantation research, outline the current state of the genome editing of bioengineered hearts and discuss the prospects of clinical application.
Collapse
Affiliation(s)
- David K C Cooper
- Center for Transplantation Sciences, Massachusetts General Hospital and Harvard Medical School, Boston, Mass
| | | | - Ryan Chaban
- Center for Transplantation Sciences, Massachusetts General Hospital and Harvard Medical School, Boston, Mass; Department of Cardiovascular Surgery, University Hospital of Johannes Gutenberg University, Mainz, Germany.
| | - Richard N Pierson
- Center for Transplantation Sciences, Massachusetts General Hospital and Harvard Medical School, Boston, Mass
| |
Collapse
|
12
|
Wang ZY, Reyes L, Estrada J, Burlak C, Gennuso VN, Tector MO, Ho S, Tector M, Tector AJ. Patients on the Transplant Waiting List Have Anti-Swine Leukocyte Antigen Class I Antibodies. Immunohorizons 2023; 7:619-625. [PMID: 37712913 PMCID: PMC10587499 DOI: 10.4049/immunohorizons.2300056] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 08/29/2023] [Indexed: 09/16/2023] Open
Abstract
Organ supply remains inadequate to meet the needs of many patients who could benefit from allotransplantation. Xenotransplantation, the use of animals as organ donors, provides an opportunity to alleviate this challenge. Pigs are widely accepted as the ideal organ donor, but humans and nonhuman primates have strong humoral immune responses to porcine tissue. Although carbohydrate xenoantigens have been studied intensively, the primate Ab response also targets class I and class II swine leukocyte Ags (SLAs). Human Abs that recognize HLAs can cross-react with SLA molecules because epitopes can be shared across species. However, ∼15% of people may also exhibit Abs toward class II SLAs despite lacking Abs that also recognize class II HLAs. Here, we extend these studies to better understand human Ab responses toward class I SLAs. When tested against a panel of 18 unique class I SLA proteins, 14 of 52 sera samples collected from patients in need of an organ transplant contained Abs that bound class I SLAs. Class I SLA-reactive sera may contain IgM only, IgG, only, or IgM and IgG capable of recognizing the pig proteins. The presence of class I HLA-reactive Abs was not essential to generating anti-class I SLA Ig. Last, anti-class I SLA reactivity varied by serum; some recognized a single SLA allele, whereas others recognized multiple class I SLA proteins.
Collapse
Affiliation(s)
- Zheng-Yu Wang
- Department of Surgery, University of Miami School of Medicine, Miami, FL
| | - Luz Reyes
- Department of Surgery, University of Miami School of Medicine, Miami, FL
| | - Jose Estrada
- Department of Surgery, University of Miami School of Medicine, Miami, FL
| | - Christopher Burlak
- Department of Surgery, University of Miami School of Medicine, Miami, FL
| | | | | | - Sam Ho
- Gift of Hope Organ and Tissue Donor Network, Itasca, IL
| | | | - A. Joseph Tector
- Department of Surgery, University of Miami School of Medicine, Miami, FL
| |
Collapse
|
13
|
Habibabady Z, McGrath G, Kinoshita K, Maenaka A, Ikechukwu I, Elias GF, Zaletel T, Rosales I, Hara H, Pierson RN, Cooper DKC. Antibody-mediated rejection in xenotransplantation: Can it be prevented or reversed? Xenotransplantation 2023; 30:e12816. [PMID: 37548030 PMCID: PMC11101061 DOI: 10.1111/xen.12816] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 07/19/2023] [Accepted: 07/26/2023] [Indexed: 08/08/2023]
Abstract
Antibody-mediated rejection (AMR) is the commonest cause of failure of a pig graft after transplantation into an immunosuppressed nonhuman primate (NHP). The incidence of AMR compared to acute cellular rejection is much higher in xenotransplantation (46% vs. 7%) than in allotransplantation (3% vs. 63%) in NHPs. Although AMR in an allograft can often be reversed, to our knowledge there is no report of its successful reversal in a pig xenograft. As there is less experience in preventing or reversing AMR in models of xenotransplantation, the results of studies in patients with allografts provide more information. These include (i) depletion or neutralization of serum anti-donor antibodies, (ii) inhibition of complement activation, (iii) therapies targeting B or plasma cells, and (iv) anti-inflammatory therapy. Depletion or neutralization of anti-pig antibody, for example, by plasmapheresis, is effective in depleting antibodies, but they recover within days. IgG-degrading enzymes do not deplete IgM. Despite the expression of human complement-regulatory proteins on the pig graft, inhibition of systemic complement activation may be necessary, particularly if AMR is to be reversed. Potential therapies include (i) inhibition of complement activation (e.g., by IVIg, C1 INH, or an anti-C5 antibody), but some complement inhibitors are not effective in NHPs, for example, eculizumab. Possible B cell-targeted therapies include (i) B cell depletion, (ii) plasma cell depletion, (iii) modulation of B cell activation, and (iv) enhancing the generation of regulatory B and/or T cells. Among anti-inflammatory agents, anti-IL6R mAb and TNF blockers are increasingly being tested in xenotransplantation models, but with no definitive evidence that they reverse AMR. Increasing attention should be directed toward testing combinations of the above therapies. We suggest that treatment with a systemic complement inhibitor is likely to be most effective, possibly combined with anti-inflammatory agents (if these are not already being administered). Ultimately, it may require further genetic engineering of the organ-source pig to resolve the problem entirely, for example, knockout or knockdown of SLA, and/or expression of PD-L1, HLA E, and/or HLA-G.
Collapse
Affiliation(s)
- Zahra Habibabady
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Gannon McGrath
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Kohei Kinoshita
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Akihiro Maenaka
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Ileka Ikechukwu
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Gabriela F. Elias
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Tjasa Zaletel
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Ivy Rosales
- Department of Pathology, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Hidetaka Hara
- Yunnan Xenotransplantation Engineering Research Center, Yunnan Agricultural University, Kunming, Yunnan, China
| | - Richard N. Pierson
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - David K. C. Cooper
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
14
|
Li S, Anwar IJ, Canning AJ, Vo-Dinh T, Kirk AD, Xu H. Xenorecognition and costimulation of porcine endothelium-derived extracellular vesicles in initiating human porcine-specific T cell immune responses. Am J Transplant 2023; 23:904-919. [PMID: 37054891 PMCID: PMC10330644 DOI: 10.1016/j.ajt.2023.04.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 04/02/2023] [Accepted: 04/04/2023] [Indexed: 04/15/2023]
Abstract
Porcine vascular endothelial cells (PECs) form a mechanistic centerpiece of xenograft rejection. Here, we determined that resting PECs release swine leukocyte antigen class I (SLA-I) but not swine leukocyte antigen class-II DR (SLA-DR) expressing extracellular vesicles (EVs) and investigated whether these EVs proficiently initiate xenoreactive T cell responses via direct xenorecognition and costimulation. Human T cells acquired SLA-I+ EVs with or without direct contact to PECs, and these EVs colocalized with T cell receptors. Although interferon gamma-activated PECs released SLA-DR+ EVs, the binding of SLA-DR+ EVs to T cells was sparse. Human T cells demonstrated low levels of proliferation without direct contact to PECs, but marked T cell proliferation was induced following exposure to EVs. EV-induced proliferation proceeded independent of monocytes/macrophages, suggesting that EVs delivered both a T cell receptor signal and costimulation. Costimulation blockade targeting B7, CD40L, or CD11a significantly reduced T cell proliferation to PEC-derived EVs. These findings indicate that endothelial-derived EVs can directly initiate T cell-mediated immune responses, and suggest that inhibiting the release of SLA-I EVs from organ xenografts has the potential to modify the xenograft rejection. We propose a secondary-direct pathway for T cell activation via xenoantigen recognition/costimulation by endothelial-derived EVs.
Collapse
Affiliation(s)
- Shu Li
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina, USA
| | - Imran J Anwar
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina, USA
| | - Aidan J Canning
- Department of Biomedical Engineering, Duke University School of Medicine, Durham, North Carolina, USA
| | - Tuan Vo-Dinh
- Department of Biomedical Engineering, Duke University School of Medicine, Durham, North Carolina, USA
| | - Allan D Kirk
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina, USA; Department of Immunology, Duke University School of Medicine, Durham, North Carolina, USA
| | - He Xu
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina, USA.
| |
Collapse
|
15
|
Hara H, Yamamoto T, Wei HJ, Cooper DK. What Have We Learned From In Vitro Studies About Pig-to-primate Organ Transplantation? Transplantation 2023; 107:1265-1277. [PMID: 36536507 PMCID: PMC10205677 DOI: 10.1097/tp.0000000000004458] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Natural preformed and de novo antibodies against pig antigens are a major cause of pig xenograft rejection in nonhuman primates (NHPs). In vivo studies in pig-to-NHP models are time consuming. In vitro assays, for example, antibody binding to pig cells, complement-dependent cytotoxicity assays, provide valuable information quickly and inexpensively. Using in vitro assays for several years, it has been documented that (1) during the first year of life, humans and NHPs develop anti-wild-type pig antibodies, but humans develop no or minimal antibody to triple-knockout (TKO) pig cells. (2) Some adult humans have no or minimal antibodies to TKO pig cells and are therefore unlikely to rapidly reject a TKO organ, particularly if the organ also expresses human "protective" proteins. (3) There is good correlation between immunoglobulin (Ig)M (but no t IgG) binding and complement injury. (4) All Old World NHPs develop antibodies to TKO pig cells and are not optimal recipients of TKO organs. (5) galactosyltransferase gene-knockout/β4GalNT2KO pigs are preferred for Old World NHPs. (6) Humans develop anti-pig IgE and IgA antibodies against pig cells, but their role remains uncertain. (7) In a small percentage of allosensitized humans, antibodies that cross-react with swine leukocyte antigens may be detrimental to a pig organ xenograft. (8) Prior sensitization to pig antigens is unlikely to be detrimental to a subsequent allograft. (9) Deletion of expression of Gal and Neu5Gc is associated with a reduction in the T-cell response to pig cells. All of these valuable observations have largely predicted the results of in vivo studies.
Collapse
Affiliation(s)
- Hidetaka Hara
- College of Veterinary Medicine, Yunnan Agricultural University, Kunming, Yunnan, China
| | - Takayuki Yamamoto
- Department of Surgery, Center for Transplantation Sciences, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| | - Hong-Jiang Wei
- College of Veterinary Medicine, Yunnan Agricultural University, Kunming, Yunnan, China
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, Yunnan, China
| | - David K.C. Cooper
- Department of Surgery, Center for Transplantation Sciences, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| |
Collapse
|
16
|
Cooper DKC, Pierson RN. Milestones on the path to clinical pig organ xenotransplantation. Am J Transplant 2023; 23:326-335. [PMID: 36775767 PMCID: PMC10127379 DOI: 10.1016/j.ajt.2022.12.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/20/2022] [Accepted: 12/28/2022] [Indexed: 01/19/2023]
Abstract
Progress in pig organ xenotransplantation has been made largely through (1) genetic engineering of the organ-source pig to protect its tissues from the human innate immune response, and (2) development of an immunosuppressive regimen based on blockade of the CD40/CD154 costimulation pathway to prevent the adaptive immune response. In the 1980s, after transplantation into nonhuman primates (NHPs), wild-type (genetically unmodified) pig organs were rejected within minutes or hours. In the 1990s, organs from pigs expressing a human complement-regulatory protein (CD55) transplanted into NHPs receiving intensive conventional immunosuppressive therapy functioned for days or weeks. When costimulation blockade was introduced in 2000, the adaptive immune response was suppressed more readily. The identification of galactose-α1,3-galactose as the major antigen target for human and NHP anti-pig antibodies in 1991 allowed for deletion of expression of galactose-α1,3-galactose in 2003, extending pig graft survival for up to 6 months. Subsequent gene editing to overcome molecular incompatibilities between the pig and primate coagulation systems proved additionally beneficial. The identification of 2 further pig carbohydrate xenoantigens allowed the production of 'triple-knockout' pigs that are preferred for clinical organ transplantation. These combined advances enabled the first clinical pig heart transplant to be performed and opened the door to formal clinical trials.
Collapse
Affiliation(s)
- David K C Cooper
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA.
| | - Richard N Pierson
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
17
|
Tector AJ, Adams AB, Tector M. Current Status of Renal Xenotransplantation and Next Steps. KIDNEY360 2023; 4:278-284. [PMID: 36821619 PMCID: PMC10103350 DOI: 10.34067/kid.0007152021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 12/18/2022] [Indexed: 12/23/2022]
Abstract
Renal transplantation is the preferred treatment of ESKD, but the shortage of suitable donor kidneys from the cadaver pool means that many patients with ESKD will not receive a kidney transplant. Xenotransplantation has long represented a solution to the kidney shortage, but the occurrence of antibody-mediated rejection has precluded its clinical development. Developments in somatic cell nuclear transfer in pigs and gene editing tools have led to the creation of new donor pigs with greatly improved crossmatches to patients. In addition, improvements in preclinical kidney xenotransplant survival using new anti-CD40/CD154-based immunosuppression have pushed xenotransplantation to the point where it is reasonable to consider initiating a clinical trial to evaluate this potential therapy in patients.
Collapse
Affiliation(s)
- Alfred J. Tector
- Department of Surgery, University of Miami School of Medicine, Miami, Florida
| | - Andrew B. Adams
- Department of Surgery, University of Minnesota School of Medicine, Minneapolis, Minnesota
| | | |
Collapse
|
18
|
Cooper DKC, Habibabady Z, Kinoshita K, Hara H, Pierson RN. The respective relevance of sensitization to alloantigens and xenoantigens in pig organ xenotransplantation. Hum Immunol 2023; 84:18-26. [PMID: 35817653 PMCID: PMC10154072 DOI: 10.1016/j.humimm.2022.06.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 06/14/2022] [Accepted: 06/20/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND Antibody-mediated rejection is a major cause of graft injury and contributes to failure of pig xenografts in nonhuman primates (NHPs). Most 'natural' or elicited antibodies found in humans and NHPs are directed against pig glycan antigens, but antibodies binding to swine leukocyte antigens (SLA) have also been detected. Of clinical importance is (i) whether the presence of high levels of antibodies directed towards human leukocyte antigens (HLA) (i.e., high panel-reactive antibodies) would be detrimental to the outcome of a pig organ xenograft; and (ii) whether, in the event of sensitization to pig antigens, a subsequent allotransplant would be at increased risk of graft failure due to elicited anti-pig antibodies that cross-react with human HLA or other antigens. SUMMARY A literature review of pig-to-primate studies indicates that relatively few highly-HLA-sensitized humans have antibodies that cross-react with pigs, predicting that most would not be at increased risk of rejecting an organ xenograft. Furthermore, the existing evidence indicates that sensitization to pig antigens will probably not elicit increased alloantibody titers; if so, 'bridging' with a pig organ could be carried out without increased risk of subsequent antibody-mediated allograft failure. KEY MESSAGE These issues have important implications for the design and conduct of clinical xenotransplantation trials.
Collapse
Affiliation(s)
- D K C Cooper
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, MA, USA.
| | - Z Habibabady
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, MA, USA
| | - K Kinoshita
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, MA, USA
| | - H Hara
- Yunnan Xenotransplantation Engineering Research Center, Yunnan Agricultural University, Kunming, Yunnan, China
| | - R N Pierson
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, MA, USA
| |
Collapse
|
19
|
Keller M, Charya A, Andargie T, Agbor-Enoh S. Laboratory Considerations for Successful Xenotransplantation in Humans. Clin Chem 2022; 68:1368-1373. [PMID: 36226752 DOI: 10.1093/clinchem/hvac150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 08/17/2022] [Indexed: 11/12/2022]
Affiliation(s)
- Michael Keller
- Laboratory of Applied Precision Omics (APO) and Genomic Research Alliance for Transplantation (GRAfT), National Institute of Health, Bethesda, MD.,Department of Critical Care Medicine, National Institute of Health, Bethesda, MD.,Pulmonary and Critical Care Medicine, Johns Hopkins Hospital,, Baltimore, MD
| | - Ananth Charya
- Division of Pulmonary and Critical Care, University of Maryland Medical Center,, Baltimore, MD
| | - Temesgen Andargie
- Laboratory of Applied Precision Omics (APO) and Genomic Research Alliance for Transplantation (GRAfT), National Institute of Health, Bethesda, MD
| | - Sean Agbor-Enoh
- Laboratory of Applied Precision Omics (APO) and Genomic Research Alliance for Transplantation (GRAfT), National Institute of Health, Bethesda, MD.,Pulmonary and Critical Care Medicine, Johns Hopkins Hospital,, Baltimore, MD
| |
Collapse
|
20
|
Anwar IJ, DeLaura I, Ladowski J, Gao Q, Knechtle SJ, Kwun J. Complement-targeted therapies in kidney transplantation-insights from preclinical studies. Front Immunol 2022; 13:984090. [PMID: 36311730 PMCID: PMC9606228 DOI: 10.3389/fimmu.2022.984090] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 09/28/2022] [Indexed: 01/21/2023] Open
Abstract
Aberrant activation of the complement system contributes to solid-organ graft dysfunction and failure. In kidney transplantation, the complement system is implicated in the pathogenesis of antibody- and cell-mediated rejection, ischemia-reperfusion injury, and vascular injury. This has led to the evaluation of select complement inhibitors (e.g., C1 and C5 inhibitors) in clinical trials with mixed results. However, the complement system is highly complex: it is composed of more than 50 fluid-phase and surface-bound elements, including several complement-activated receptors-all potential therapeutic targets in kidney transplantation. Generation of targeted pharmaceuticals and use of gene editing tools have led to an improved understanding of the intricacies of the complement system in allo- and xeno-transplantation. This review summarizes our current knowledge of the role of the complement system as it relates to rejection in kidney transplantation, specifically reviewing evidence gained from pre-clinical models (rodent and nonhuman primate) that may potentially be translated to clinical trials.
Collapse
Affiliation(s)
| | | | | | | | - Stuart J. Knechtle
- Duke Transplant Center, Department of Surgery, Duke University School of Medicine, Durham, NC, United States
| | - Jean Kwun
- Duke Transplant Center, Department of Surgery, Duke University School of Medicine, Durham, NC, United States
| |
Collapse
|
21
|
Oscherwitz M, Nguyen HQ, Raza SS, Cleveland DC, Padilla LA, Sorabella RA, Ayares D, Maxwell K, Rhodes LA, Cooper DKC, Hara H. Will previous palliative surgery for congenital heart disease be detrimental to subsequent pig heart xenotransplantation? Transpl Immunol 2022; 74:101661. [PMID: 35787933 PMCID: PMC9762890 DOI: 10.1016/j.trim.2022.101661] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 06/27/2022] [Accepted: 06/28/2022] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Pig heart xenotransplantation might act as a bridge in infants with complex congenital heart disease (CHD) until a deceased human donor heart becomes available. Infants develop antibodies to wild-type (WT, i.e., genetically-unmodified) pig cells, but rarely to cells in which expression of the 3 known carbohydrate xenoantigens has been deleted by genetic engineering (triple-knockout [TKO] pigs). Our objective was to test sera from children who had undergone palliative surgery for complex CHD (and who potentially might need a pig heart transplant) to determine whether they had serum cytotoxic antibodies against TKO pig cells. METHODS Sera were obtained from children with CHD undergoing Glenn or Fontan operation (n = 14) and healthy adults (n = 8, as controls). All of the children had complex CHD and had undergone some form of cardiac surgery. Seven had received human blood transfusions and 3 bovine pericardial patch grafts. IgM and IgG binding to WT and TKO pig red blood cells (RBCs) and peripheral blood mononuclear cells (PBMCs) were measured by flow cytometry, and killing of PBMCs by a complement-dependent cytotoxicity assay. RESULTS Almost all children and adults demonstrated relatively high IgM/IgG binding to WT RBCs, but minimal binding to TKO RBCs (p < 0.0001 vs WT), although IgG binding was greater in children than adults (p < 0.01). All sera showed IgM/IgG binding to WT PBMCs, but this was much lower to TKO PBMCs (p < 0.0001 vs WT) and was greater in children than in adults (p < 0.05). Binding to both WT and TKO PBMCs was greater than to RBCs. Mean serum cytotoxicity to WT PBMCs was 90% in both children and adults, whereas to TKO PBMCs it was only 20% and < 5%, respectively. The sera from 6/14 (43%) children were cytotoxic to TKO PBMCs, but no adult sera were cytotoxic. CONCLUSIONS Although no children had high levels of antibodies to TKO RBCs, 13/14 demonstrated antibodies to TKO PBMCs, in 6 of these showed mild cytotoxicity. As no adults had cytotoxic antibodies to TKO PBMCs, the higher incidence in children may possibly be associated with their exposure to previous cardiac surgery and biological products. However, the numbers were too small to determine the influence of such past exposures. Before considering pig heart xenotransplantation for children with CHD, testing for antibody binding may be warranted.
Collapse
Affiliation(s)
- Max Oscherwitz
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Huy Quoc Nguyen
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Syed Sikandar Raza
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - David C Cleveland
- Division of Cardiothoracic Surgery, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Luz A Padilla
- Division of Cardiothoracic Surgery, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Robert A Sorabella
- Division of Cardiothoracic Surgery, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | - Kathryn Maxwell
- Division of Cardiothoracic Surgery, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Leslie A Rhodes
- Department of Pediatric Cardiology, Division of Critical Care, 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
| | - Hidetaka Hara
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA.
| |
Collapse
|
22
|
An Efficacious Transgenic Strategy for Triple Knockout of Xeno-Reactive Antigen Genes GGTA1, CMAH, and B4GALNT2 from Jeju Native Pigs. Vaccines (Basel) 2022; 10:vaccines10091503. [PMID: 36146581 PMCID: PMC9505423 DOI: 10.3390/vaccines10091503] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 09/01/2022] [Accepted: 09/06/2022] [Indexed: 11/17/2022] Open
Abstract
Pigs are promising donors of biological materials for xenotransplantation; however, cell surface carbohydrate antigens, including galactose-alpha-1,3-galactose (α-Gal), N-glycolylneuraminic acid (Neu5Gc), and Sd blood group antigens, play a significant role in porcine xenograft rejection. Inactivating swine endogenous genes, including GGTA1, CMAH, and B4GALNT2, decreases the binding ratio of human IgG/IgM in peripheral blood mononuclear cells and erythrocytes and impedes the effectiveness of α-Gal, Neu5Gc, and Sd, thereby successfully preventing hyperacute rejection. Therefore, in this study, an effective transgenic system was developed to target GGTA1, CMAH, and B4GALNT2 using CRISPR-CAS9 and develop triple-knockout pigs. The findings revealed that all three antigens (α-Gal, Neu5Gc, and Sd) were not expressed in the heart, lungs, or liver of the triple-knockout Jeju Native Pigs (JNPs), and poor expression of α-Gal and Neu5G was confirmed in the kidneys. Compared with the kidney, heart, and lung tissues from wild-type JNPs, those from GGTA1/CMAH/ B4GALNT2 knockout-recipient JNPs exhibited reduced human IgM and IgG binding and expression of each immunological rejection component. Hence, reducing the expression of swine xenogeneic antigens identifiable by human immunoglobulins can lessen the immunological rejection against xenotransplantation. The findings support the possibility of employing knockout JNP organs for xenogeneic transplantation to minimize or completely eradicate rejection using multiple gene-editing methods.
Collapse
|
23
|
Jiang Z, Fu M, Zhu D, Wang X, Li N, Ren L, He J, Yang G. Genetically modified immunomodulatory cell-based biomaterials in tissue regeneration and engineering. Cytokine Growth Factor Rev 2022; 66:53-73. [PMID: 35690567 DOI: 10.1016/j.cytogfr.2022.05.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 05/24/2022] [Indexed: 11/25/2022]
Abstract
To date, the wide application of cell-based biomaterials in tissue engineering and regeneration is remarkably hampered by immune rejection. Reducing the immunogenicity of cell-based biomaterials has become the latest direction in biomaterial research. Recently, genetically modified cell-based biomaterials with immunomodulatory genes have become a feasible solution to the immunogenicity problem. In this review, recent advances and future challenges of genetically modified immunomodulatory cell-based biomaterials are elaborated, including fabrication approaches, mechanisms of common immunomodulatory genes, application and, more importantly, current preclinical and clinical advances. The fabrication approaches can be categorized into commonly used (e.g., virus transfection) and newly developed approaches. The immunomodulatory mechanisms of representative genes involve complicated cell signaling pathways and metabolic activities. Wide application in curing multiple end-term diseases and replacing lifelong immunosuppressive therapy in multiple cell and organ transplantation models is demonstrated. Most significantly, practices of genetically modified organ transplantation have been conducted on brain-dead human decedent and even on living patients after a series of experiments on nonhuman primates. Nevertheless, uncertain biosecurity, nonspecific effects and overlooked personalization of current genetically modified immunomodulatory cell-based biomaterials are shortcomings that remain to be overcome.
Collapse
Affiliation(s)
- Zhiwei Jiang
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center of Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou 310000, China
| | - Mengdie Fu
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center of Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou 310000, China
| | - Danji Zhu
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center of Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou 310000, China
| | - Xueting Wang
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center of Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou 310000, China
| | - Na Li
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center of Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou 310000, China
| | - Lingfei Ren
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center of Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou 310000, China
| | - Jin He
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center of Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou 310000, China
| | - Guoli Yang
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center of Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou 310000, China.
| |
Collapse
|
24
|
Xu K, Yu H, Chen S, Zhang Y, Guo J, Yang C, Jiao D, Nguyen TD, Zhao H, Wang J, Wei T, Li H, Jia B, Jamal MA, Zhao HY, Huang X, Wei HJ. Production of Triple-Gene (GGTA1, B2M and CIITA)-Modified Donor Pigs for Xenotransplantation. Front Vet Sci 2022; 9:848833. [PMID: 35573408 PMCID: PMC9097228 DOI: 10.3389/fvets.2022.848833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 03/28/2022] [Indexed: 11/13/2022] Open
Abstract
Activation of human immune T-cells by swine leukocyte antigens class I (SLA-I) and class II (SLA-II) leads to xenograft destruction. Here, we generated the GGTA1, B2M, and CIITA (GBC) triple-gene-modified Diannan miniature pigs, analyzed the transcriptome of GBC-modified peripheral blood mononuclear cells (PBMCs) in the pig's spleen, and investigated their effectiveness in anti-immunological rejection. A total of six cloned piglets were successfully generated using somatic cell nuclear transfer, one of them carrying the heterozygous mutations in triple genes and the other five piglets carrying the homozygous mutations in GGTA1 and CIITA genes, but have the heterozygous mutation in the B2M gene. The autopsy of GBC-modified pigs revealed that a lot of spot bleeding in the kidney, severe suppuration and necrosis in the lungs, enlarged peripulmonary lymph nodes, and adhesion between the lungs and chest wall were found. Phenotyping data showed that the mRNA expressions of triple genes and protein expressions of B2M and CIITA genes were still detectable and comparable with wild-type (WT) pigs in multiple tissues, but α1,3-galactosyltransferase was eliminated, SLA-I was significantly decreased, and four subtypes of SLA-II were absent in GBC-modified pigs. In addition, even in swine umbilical vein endothelial cells (SUVEC) induced by recombinant porcine interferon gamma (IFN-γ), the expression of SLA-I in GBC-modified pig was lower than that in WT pigs. Similarly, the expression of SLA-II DR and DQ also cannot be induced by recombinant porcine IFN-γ. Through RNA sequencing (RNA-seq), 150 differentially expressed genes were identified in the PBMCs of the pig's spleen, and most of them were involved in immune- and infection-relevant pathways that include antigen processing and presentation and viral myocarditis, resulting in the pigs with GBC modification being susceptible to pathogenic microorganism. Furthermore, the numbers of human IgM binding to the fibroblast cells of GBC-modified pigs were obviously reduced. The GBC-modified porcine PBMCs triggered the weaker proliferation of human PBMCs than WT PBMCs. These findings indicated that the absence of the expression of α1,3-galactosyltransferase and SLA-II and the downregulation of SLA-I enhanced the ability of immunological tolerance in pig-to-human xenotransplantation.
Collapse
Affiliation(s)
- Kaixiang Xu
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China.,Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming, China
| | - Honghao Yu
- College of Biotechnology, Guilin Medical University, Guilin, China
| | - Shuhan Chen
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China.,College of Veterinary Medicine, Yunnan Agricultural University, Kunming, China
| | - Yaxuan Zhang
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China.,College of Veterinary Medicine, Yunnan Agricultural University, Kunming, China
| | - Jianxiong Guo
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China
| | - Chang Yang
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China
| | - Deling Jiao
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China.,Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming, China
| | - Tien Dat Nguyen
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China.,Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming, China
| | - Heng Zhao
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China.,College of Veterinary Medicine, Yunnan Agricultural University, Kunming, China
| | - Jiaoxiang Wang
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China.,Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming, China
| | - Taiyun Wei
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China
| | - Honghui Li
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China.,Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming, China
| | - Baoyu Jia
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China.,College of Veterinary Medicine, Yunnan Agricultural University, Kunming, China
| | - Muhammad Ameen Jamal
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China.,Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming, China
| | - Hong-Ye Zhao
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China
| | - Xingxu Huang
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Hong-Jiang Wei
- Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation, Yunnan Agricultural University, Kunming, China.,Yunnan Province Xenotransplantation Research Engineering Center, Yunnan Agricultural University, Kunming, China.,Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming, China.,College of Veterinary Medicine, Yunnan Agricultural University, Kunming, China
| |
Collapse
|
25
|
Porrett PM, Orandi BJ, Kumar V, Houp J, Anderson D, Cozette Killian A, Hauptfeld-Dolejsek V, Martin DE, Macedon S, Budd N, Stegner KL, Dandro A, Kokkinaki M, Kuravi KV, Reed RD, Fatima H, Killian JT, Baker G, Perry J, Wright ED, Cheung MD, Erman EN, Kraebber K, Gamblin T, Guy L, George JF, Ayares D, Locke JE. First clinical-grade porcine kidney xenotransplant using a human decedent model. Am J Transplant 2022; 22:1037-1053. [PMID: 35049121 DOI: 10.1111/ajt.16930] [Citation(s) in RCA: 190] [Impact Index Per Article: 95.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 12/15/2021] [Accepted: 12/16/2021] [Indexed: 01/25/2023]
Abstract
A radical solution is needed for the organ supply crisis, and the domestic pig is a promising organ source. In preparation for a clinical trial of xenotransplantation, we developed an in vivo pre-clinical human model to test safety and feasibility tenets established in animal models. After performance of a novel, prospective compatible crossmatch, we performed bilateral native nephrectomies in a human brain-dead decedent and subsequently transplanted two kidneys from a pig genetically engineered for human xenotransplantation. The decedent was hemodynamically stable through reperfusion, and vascular integrity was maintained despite the exposure of the xenografts to human blood pressure. No hyperacute rejection was observed, and the kidneys remained viable until termination 74 h later. No chimerism or transmission of porcine retroviruses was detected. Longitudinal biopsies revealed thrombotic microangiopathy that did not progress in severity, without evidence of cellular rejection or deposition of antibody or complement proteins. Although the xenografts produced variable amounts of urine, creatinine clearance did not recover. Whether renal recovery was impacted by the milieu of brain death and/or microvascular injury remains unknown. In summary, our study suggests that major barriers to human xenotransplantation have been surmounted and identifies where new knowledge is needed to optimize xenotransplantation outcomes in humans.
Collapse
Affiliation(s)
- Paige M Porrett
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Babak J Orandi
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Vineeta Kumar
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Julie Houp
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Douglas Anderson
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - A Cozette Killian
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | | | | | - Sara Macedon
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Natalie Budd
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Katherine L Stegner
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Amy Dandro
- Revivicor, Inc, Blacksburg, Virginia, USA
| | | | | | - Rhiannon D Reed
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Huma Fatima
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - John T Killian
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Gavin Baker
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Jackson Perry
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Emma D Wright
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Matthew D Cheung
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Elise N Erman
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Karl Kraebber
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Tracy Gamblin
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Linda Guy
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - James F George
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | | | - Jayme E Locke
- University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| |
Collapse
|
26
|
Li T, Feng H, Du J, Xia Q, Cooper DKC, Jiang H, He S, Pan D, Chen G, Wang Y. Serum Antibody Binding and Cytotoxicity to Pig Cells in Chinese Subjects: Relevance to Clinical Renal Xenotransplantation. Front Immunol 2022; 13:844632. [PMID: 35418974 PMCID: PMC8996717 DOI: 10.3389/fimmu.2022.844632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 02/18/2022] [Indexed: 11/20/2022] Open
Abstract
Kidney xenotransplantation is expected to contribute to resolving the shortage of kidneys from deceased human donors. Although progress in experimental life-supporting pig renal xenotransplantation has been encouraging, there are still issues to be considered before a clinical trial can be initiated. We attempted to clarify some of these by an in vitro study. Blood was drawn from healthy volunteers (Volunteers, n=20), patients with end-stage renal disease (ESRD, n=20) pre-operation (Pre), and on Day 1 (POD 1) and Day 14 (POD 14) after renal allotransplantation, brain-dead organ donors (DBD, n=20), and renal allotransplant recipients who were currently experiencing T cell-mediated rejection (Allo-TCMR, n=20). Serum IgM/IgG binding to, and complement-dependent cytotoxicity (CDC) of, PBMCs and RBCs from (a) wild-type (WT), (b) α1,3-galactosyltransferase gene-knockout (GTKO), (c) GTKO/beta-1,4-N-acety1 galactosaminyltransferase 2-knockout (GTKO/β4GalNT2KO), (d) GTKO/cytidine monophosphate-N-acetylneuraminic acid hydroxylase-knockout (GTKO/CMAHKO), and (e) GTKO/β4GalNT2KO/CMAHKO/hCD55 (TKO/hCD55) pigs were measured by flow cytometry. We obtained the following results: (i) Serum IgM/IgG binding and CDC in Volunteers were significantly greater to WT, GTKO, and GTKO/β4GalNT2KO PBMCs or RBCs than to GTKO/CMAHKO and TKO/hCD55 cells; (ii) ESRD, DBD, and Allo-TCMR serum antibody binding and CDC to WT pig PBMCs were significantly greater than to GTKO, GTKO/β4GalNT2KO, GTKO/CMAHKO, and TKO/hCD55 cells; (iii) antibody binding to GTKO/CMAHKO pig cells was significantly lower in hemodialysis than peritoneal dialysis patients. (iv) Two of twenty allotransplantation recipients' serum IgG binding to GTKO pig PBMCs increased on POD14 compared with Pre, but IgG binding to GTKO pig RBCs did not; (v) In all sera, the lowest antibody binding and CDC were to GTKO/CMAHKO and TKO/CD55 pig cells. We conclude (i) CMAHKO in the pig may be critical to the success of clinical pig kidney xenotransplantation, and may be the most important after GTKO, at least in Chinese patients; (ii) subjects with ESRD, or who are immunosuppressed after kidney allotransplantation, and DBD, have lower levels of antibody binding and CDC to genetically-engineered pig cells than do volunteers; (iii) TKO pigs with selected human 'protective' transgenes, e.g., CD55, are likely to prove to be the optimal sources of kidneys for clinical xenotransplantation.
Collapse
Affiliation(s)
- Tao Li
- Department of Organ Transplantation, The Second Affiliated Hospital of Hainan Medical University, The Transplantation Institute of Hainan Medical University, Haikou, China
| | - Hao Feng
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Organ Transplantation, Ministry of Education and National Health Commission (NHC), Chinese Academy of Medical Sciences, Wuhan, China
| | - Jiaxiang Du
- Genetic Engineering Department, Chengdu Clonorgan Biotechnology Co., Ltd., Chengdu, China
| | - Qiangbing Xia
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Organ Transplantation, Ministry of Education and National Health Commission (NHC), Chinese Academy of Medical Sciences, Wuhan, China
| | - David K. C. Cooper
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital/Harvard Medical School, Boston, MA, United States
| | - Hongtao Jiang
- Department of Organ Transplantation, The Second Affiliated Hospital of Hainan Medical University, The Transplantation Institute of Hainan Medical University, Haikou, China
| | - Songzhe He
- Department of Organ Transplantation, The Second Affiliated Hospital of Hainan Medical University, The Transplantation Institute of Hainan Medical University, Haikou, China
| | - Dengke Pan
- Clinical Immunology Translational Medicine Key Laboratory of Sichuan Province, Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital, Chengdu, China
- *Correspondence: Yi Wang, ; Gang Chen, ; Dengke Pan,
| | - Gang Chen
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Organ Transplantation, Ministry of Education and National Health Commission (NHC), Chinese Academy of Medical Sciences, Wuhan, China
- *Correspondence: Yi Wang, ; Gang Chen, ; Dengke Pan,
| | - Yi Wang
- Department of Organ Transplantation, The Second Affiliated Hospital of Hainan Medical University, The Transplantation Institute of Hainan Medical University, Haikou, China
- Department of Urology, Second Affiliated Hospital of University of South China, Hengyang, China
- *Correspondence: Yi Wang, ; Gang Chen, ; Dengke Pan,
| |
Collapse
|
27
|
Reichart B, Längin M, Denner J, Schwinzer R, Cowan PJ, Wolf E. Pathways to Clinical Cardiac Xenotransplantation. Transplantation 2021; 105:1930-1943. [PMID: 33350675 DOI: 10.1097/tp.0000000000003588] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Heart transplantation is the only long-lasting lifesaving option for patients with terminal cardiac failure. The number of available human organs is however far below the actual need, resulting in substantial mortality of patients while waiting for a human heart. Mechanical assist devices are used to support cardiac function but are associated with a high risk of severe complications and poor quality of life for the patients. Consistent success in orthotopic transplantation of genetically modified pig hearts into baboons indicates that cardiac xenotransplantation may become a clinically applicable option for heart failure patients who cannot get a human heart transplant. In this overview, we project potential paths to clinical cardiac xenotransplantation, including the choice of genetically modified source pigs; associated requirements of microbiological, including virological, safety; optimized matching of source pig and recipient; and specific treatments of the donor heart after explantation and of the recipients. Moreover, selection of patients and the regulatory framework will be discussed.
Collapse
Affiliation(s)
- Bruno Reichart
- Walter Brendel Center for Experimental Medicine, LMU Munich, Munich, Germany
| | - Matthias Längin
- Department of Anaesthesiology, University Hospital, LMU Munich, Munich, Germany
| | - Joachim Denner
- Institute of Virology, Free University Berlin, Berlin, Germany
| | - Reinhard Schwinzer
- Department of General-, Visceral-, and Transplantation Surgery, Transplant Laboratory, Hannover Medical School, Hannover, Germany
| | - Peter J Cowan
- Immunology Research Centre, St. Vincent's Hospital Melbourne, Victoria, Australia
- Department of Medicine, University of Melbourne, VIC, Australia
| | - Eckhard Wolf
- Institute of Molecular Animal Breeding and Biotechnology, Gene Center, LMU Munich, Munich, Germany
- Department of Veterinary Sciences, and Center for Innovative Medical Models (CiMM), LMU Munich, Munich, Germany
| |
Collapse
|
28
|
Jagdale A, Kumar V, Anderson DJ, Locke JE, Hanaway MJ, Eckhoff DE, Iwase H, Cooper DK. Suggested Patient Selection Criteria for Initial Clinical Trials of Pig Kidney Xenotransplantation in the United States. Transplantation 2021; 105:1904-1908. [PMID: 33481554 PMCID: PMC10124769 DOI: 10.1097/tp.0000000000003632] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
There is a critical shortage of kidneys for transplantation into patients with kidney failure. Genetically-engineered pigs could provide an additional source. Increasing success is being reported of the transplantation of pig kidneys in nonhuman primates. Consideration is now being given to the selection of patients for the first clinical trial of pig kidney transplantation. In some US states, patients aged 55–65, particularly if of blood group O, may wait >5 years for a donor organ, by which time >50% are likely to have died or removed from the wait-list because they are no longer acceptable for transplantation. We suggest these patients, if otherwise healthy, might accept the opportunity of early pig kidney transplantation.
Collapse
Affiliation(s)
- Abhijit Jagdale
- Xenotransplantation Program, Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Vineeta Kumar
- Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Douglas J. Anderson
- Xenotransplantation Program, Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jayme E. Locke
- Xenotransplantation Program, Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Michael J. Hanaway
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Devin E. Eckhoff
- Xenotransplantation Program, Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Hayato Iwase
- Xenotransplantation Program, Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - David K.C. Cooper
- Xenotransplantation Program, Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| |
Collapse
|
29
|
Tritschler H, Fischer K, Seissler J, Fiedler J, Halbgebauer R, Huber-Lang M, Schnieke A, Brenner RE. New Insights into Xenotransplantation for Cartilage Repair: Porcine Multi-Genetically Modified Chondrocytes as a Promising Cell Source. Cells 2021; 10:cells10082152. [PMID: 34440921 PMCID: PMC8394410 DOI: 10.3390/cells10082152] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/16/2021] [Accepted: 08/18/2021] [Indexed: 02/07/2023] Open
Abstract
Transplantation of xenogenic porcine chondrocytes could represent a future strategy for the treatment of human articular cartilage defects. Major obstacles are humoral and cellular rejection processes triggered by xenogenic epitopes like α-1,3-Gal and Neu5Gc. Besides knockout (KO) of genes responsible for the biosynthesis of respective epitopes (GGTA1 and CMAH), transgenic expression of human complement inhibitors and anti-apoptotic as well as anti-inflammatory factors (CD46, CD55, CD59, TNFAIP3 and HMOX1) could synergistically prevent hyperacute xenograft rejection. Therefore, chondrocytes from different strains of single- or multi-genetically modified pigs were characterized concerning their protection from xenogeneic complement activation. Articular chondrocytes were isolated from the knee joints of WT, GalTKO, GalT/CMAH-KO, human CD59/CD55//CD46/TNFAIP3/HMOX1-transgenic (TG), GalTKO/TG and GalT/CMAHKO/TG pigs. The tissue-specific effectiveness of the genetic modifications was tested on gene, protein and epitope expression level or by functional assays. After exposure to 20% and 40% normal human serum (NHS), deposition of C3b/iC3b/C3c and formation of the terminal complement complex (TCC, C5b-9) was quantified by specific cell ELISAs, and generation of the anaphylatoxin C5a by ELISA. Chondrocyte lysis was analyzed by Trypan Blue Exclusion Assay. In all respective KO variants, the absence of α -1,3-Gal and Neu5Gc epitope was verified by FACS analysis. In chondrocytes derived from TG animals, expression of CD55 and CD59 could be confirmed on gene and protein level, TNFAIP3 on gene expression level as well as by functional assays and CD46 only on gene expression level whereas transgenic HMOX1 expression was not evident. Complement activation in the presence of NHS indicated mainly effective although incomplete protection against C3b/iC3b/C3c deposition, C5a-generation and C5b-9 formation being lowest in single GalTKO. Chondrocyte viability under exposure to NHS was significantly improved even by single GalTKO and completely preserved by all other variants including TG chondrocytes without KO of xenoepitopes.
Collapse
Affiliation(s)
- Hanna Tritschler
- Division for Biochemistry of Joint and Connective Tissue Diseases, Department of Orthopedics, University of Ulm, 89081 Ulm, Germany; (H.T.); (J.F.)
| | - Konrad Fischer
- Chair of Livestock Biotechnology, School of Life Sciences Weihenstephan, Technische Universität München, 85354 Freising, Germany; (K.F.); (A.S.)
| | - Jochen Seissler
- Medizinische Klinik und Poliklinik IV, Diabetes Zentrum—Campus Innenstadt, Klinikum der Ludwig-Maximilians-Universität, 80336 München, Germany;
| | - Jörg Fiedler
- Division for Biochemistry of Joint and Connective Tissue Diseases, Department of Orthopedics, University of Ulm, 89081 Ulm, Germany; (H.T.); (J.F.)
| | - Rebecca Halbgebauer
- Institute of Clinical and Experimental Trauma Immunology, University Hospital Ulm, 89081 Ulm, Germany; (R.H.); (M.H.-L.)
| | - Markus Huber-Lang
- Institute of Clinical and Experimental Trauma Immunology, University Hospital Ulm, 89081 Ulm, Germany; (R.H.); (M.H.-L.)
| | - Angelika Schnieke
- Chair of Livestock Biotechnology, School of Life Sciences Weihenstephan, Technische Universität München, 85354 Freising, Germany; (K.F.); (A.S.)
| | - Rolf E. Brenner
- Division for Biochemistry of Joint and Connective Tissue Diseases, Department of Orthopedics, University of Ulm, 89081 Ulm, Germany; (H.T.); (J.F.)
- Correspondence: ; Tel.: +49-731-500-63280
| |
Collapse
|
30
|
Ladowski JM, Houp J, Hauptfeld-Dolejsek V, Javed M, Hara H, Cooper DKC. Aspects of histocompatibility testing in xenotransplantation. Transpl Immunol 2021; 67:101409. [PMID: 34015463 PMCID: PMC8197754 DOI: 10.1016/j.trim.2021.101409] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 05/14/2021] [Indexed: 12/16/2022]
Abstract
Xenotransplantation, using genetically-modified pigs for clinical organ transplantation, is a solution to the organ shortage. The biggest barrier to clinical implementation is the antigenicity of pig cells. Humans possess preformed antibody to pig cells that initiate antibody-mediated rejection of pig organs in primates. Advances in genetic engineering have led to the development of a pig lacking the three known glycan xenoantigens (triple-knockout [TKO] pigs). A significant number of human sera demonstrate no antibody binding to TKO pig cells. As a result of the TKO pig's low antigen expression, survival of life-supporting pig organs in immunosuppressed nonhuman primates has significantly increased, and hope has been renewed for clinical trials of xenotransplantation. It is important to understand the context in which xenotransplantation's predecessor, allotransplantation, has been successful, and the steps needed for the success of xenotransplantation. Successful allotransplantation has been based on two main immunological approaches - (i) adequate immunosuppressive therapy, and (ii) careful histocompatibility matching. In vivo studies suggest that the available immunosuppressive regimens are adequate to suppress the human anti-pig cellular response. Methods to evaluate and screen patients for the first clinical xenotransplantation trial are the next challenge. The goal of this review is to summarize the history of histocompatibility testing, and the available tools that can be utilized to determine xenograft histocompatibility.
Collapse
Affiliation(s)
- Joseph M Ladowski
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Julie Houp
- Histocompatibility Laboratory, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | - Mariyam Javed
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Hidetaka Hara
- Xenotransplantation Program, Department of Surgery, 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
| |
Collapse
|
31
|
Song S, Manook M, Kwun J, Jackson AM, Knechtle SJ, Kelsoe G. Allo-Specific Humoral Responses: New Methods for Screening Donor-Specific Antibody and Characterization of HLA-Specific Memory B Cells. Front Immunol 2021; 12:705140. [PMID: 34326847 PMCID: PMC8313870 DOI: 10.3389/fimmu.2021.705140] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 06/22/2021] [Indexed: 12/28/2022] Open
Abstract
Antibody-mediated allograft rejection (AMR) causes more kidney transplant failure than any other single cause. AMR is mediated by antibodies recognizing antigens expressed by the graft, and antibodies generated against major histocompatibility complex (MHC) mismatches are especially problematic. Most research directed towards the management of clinical AMR has focused on identifying and characterizing circulating donor-specific HLA antibody (DSA) and optimizing therapies that reduce B-cell activation and/or block antibody secretion by inhibiting plasmacyte survival. Here we describe a novel set of reagents and techniques to allow more specific measurements of MHC sensitization across different animal transplant models. Additionally, we have used these approaches to isolate and clone individual HLA-specific B cells from patients sensitized by pregnancy or transplantation. We have identified and characterized the phenotypes of individual HLA-specific B cells, determined the V(D)J rearrangements of their paired H and L chains, and generated recombinant antibodies to determine affinity and specificity. Knowledge of the BCR genes of individual HLA-specific B cells will allow identification of clonally related B cells by high-throughput sequence analysis of peripheral blood mononuclear cells and permit us to re-construct the origins of HLA-specific B cells and follow their somatic evolution by mutation and selection.
Collapse
Affiliation(s)
- Shengli Song
- Department of Immunology, Duke University School of Medicine, Durham, NC, United States
| | - Miriam Manook
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States
| | - Jean Kwun
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States
| | - Annette M. Jackson
- Department of Immunology, Duke University School of Medicine, Durham, NC, United States
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States
| | - Stuart J. Knechtle
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States
| | - Garnett Kelsoe
- Department of Immunology, Duke University School of Medicine, Durham, NC, United States
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States
| |
Collapse
|
32
|
Li P, Walsh JR, Lopez K, Isidan A, Zhang W, Chen AM, Goggins WC, Higgins NG, Liu J, Brutkiewicz RR, Smith LJ, Hara H, Cooper DKC, Ekser B. Genetic engineering of porcine endothelial cell lines for evaluation of human-to-pig xenoreactive immune responses. Sci Rep 2021; 11:13131. [PMID: 34162938 PMCID: PMC8222275 DOI: 10.1038/s41598-021-92543-y] [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: 01/12/2021] [Accepted: 06/08/2021] [Indexed: 01/25/2023] Open
Abstract
Xenotransplantation (cross-species transplantation) using genetically-engineered pig organs offers a potential solution to address persistent organ shortage. Current evaluation of porcine genetic modifications is to monitor the nonhuman primate immune response and survival after pig organ xenotransplantation. This measure is an essential step before clinical xenotransplantation trials, but it is time-consuming, costly, and inefficient with many variables. We developed an efficient approach to quickly examine human-to-pig xeno-immune responses in vitro. A porcine endothelial cell was characterized and immortalized for genetic modification. Five genes including GGTA1, CMAH, β4galNT2, SLA-I α chain, and β2-microglobulin that are responsible for the production of major xenoantigens (αGal, Neu5Gc, Sda, and SLA-I) were sequentially disrupted in immortalized porcine endothelial cells using CRISPR/Cas9 technology. The elimination of αGal, Neu5Gc, Sda, and SLA-I dramatically reduced the antigenicity of the porcine cells, though the cells still retained their ability to provoke human natural killer cell activation. In summary, evaluation of human immune responses to genetically modified porcine cells in vitro provides an efficient method to identify ideal combinations of genetic modifications for improving pig-to-human compatibility, which should accelerate the application of xenotransplantation to humans.
Collapse
Affiliation(s)
- Ping Li
- Division of Transplant Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, IN, USA.
| | - Julia R Walsh
- Division of Transplant Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, IN, USA.,Weldon School of Biomedical Engineering, West Lafayette, IN, USA
| | - Kevin Lopez
- Division of Transplant Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Abdulkadir Isidan
- Division of Transplant Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Wenjun Zhang
- Division of Transplant Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Angela M Chen
- Division of Transplant Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - William C Goggins
- Division of Transplant Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | | | - Jianyun Liu
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Randy R Brutkiewicz
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Lester J Smith
- Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, USA.,3D Bioprinting Core, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Hidetaka Hara
- Xenotransplantation Program, Department of Surgery, University of Birmingham at Alabama, Birmingham, AL, USA
| | - David K C Cooper
- Xenotransplantation Program, Department of Surgery, University of Birmingham at Alabama, Birmingham, AL, USA
| | - Burcin Ekser
- Division of Transplant Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, IN, USA.
| |
Collapse
|
33
|
Characterization of encapsulated porcine cardiosphere-derived cells embedded in 3D alginate matrices. Int J Pharm 2021; 599:120454. [PMID: 33676988 DOI: 10.1016/j.ijpharm.2021.120454] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/23/2021] [Accepted: 03/01/2021] [Indexed: 12/22/2022]
Abstract
Myocardial infarction is caused by an interruption of coronary blood flow, leading to one of the main death causes worldwide. Current therapeutic approaches are palliative and not able to solve the loss of cardiac tissue. Cardiosphere derived cells (CDCs) reduce scarring, and increase viable myocardium, with safety and adequate biodistribution, but show a low rate engraftment and survival after implantation. In order to solve the low retention, we propose the encapsulation of CDCs within three-dimensional alginate-poly-L-lysine-alginate matrix as therapy for cardiac regeneration. In this work, we demonstrate the encapsulation of CDCs in alginate matrix, with no decrease in viability over a month, and showing the preservation of CDCs phenotype, differentiation potential, gene expression profile and growth factor release after encapsulation, moving a step forward to clinical translation of CDCs therapy in regeneration in heart failure.
Collapse
|
34
|
A comparative analysis of SLA-DRB1 genetic diversity in Colombian (creoles and commercial line) and worldwide swine populations. Sci Rep 2021; 11:4340. [PMID: 33619347 PMCID: PMC7900169 DOI: 10.1038/s41598-021-83637-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 01/18/2021] [Indexed: 12/30/2022] Open
Abstract
Analysing pig class II mayor histocompatibility complex (MHC) molecules is mainly related to antigen presentation. Identifying frequently-occurring alleles in pig populations is an important aspect to be considered when developing peptide-based vaccines. Colombian creole pig populations have had to adapt to local conditions since entering Colombia; a recent census has shown low amounts of pigs which is why they are considered protected by the Colombian government. Commercial hybrids are more attractive regarding production. This research has been aimed at describing the allele distribution of Colombian pigs from diverse genetic backgrounds and comparing Colombian SLA-DRB1 locus diversity to that of internationally reported populations. Twenty SLA-DRB1 alleles were identified in the six populations analysed here using sequence-based typing. The amount of alleles ranged from six (Manta and Casco Mula) to nine (San Pedreño). Only one allele (01:02) having > 5% frequency was shared by all three commercial line populations. Allele 02:01:01 was shared by five populations (around > 5% frequency). Global FST indicated that pig populations were clearly structured, as 20.6% of total allele frequency variation was explained by differences between populations (FST = 0.206). This study’s results confirmed that the greatest diversity occurred in wild boars, thereby contrasting with low diversity in domestic pig populations.
Collapse
|
35
|
Abstract
Advances in genetic engineering, particularly CRISPR/Cas9, have resulted in the development of a triple glycan-knockout (TKO) pig. There is minimal human antipig antibody binding to TKO pig cells. The TKO background has decreased antibody binding to a sufficiently low level that any additional xenoantigens expressed on the cells can now be more easily detected. One of these xenoantigens is the swine major histocompatibility complex, termed swine leukocyte antigens (SLA). SLA are the homolog to HLAs, a protein complex expressed on human tissue capable of stimulating the development of new antibodies in allotransplantation. These antibodies can result in graft failure through hyperacute, acute, or chronic rejection. Our knowledge of SLA, particularly in the last 5 years, has grown considerably. The presence, cause, and methods to detect anti-SLA antibodies will need to be carefully considered for the first clinical trial of xenotransplantation. The focus of this review is to summarize the role of SLA in xenotransplantation and consider whether it will prove to be a major barrier. Techniques are now available to mutate target SLA amino acids to ensure that cross-reactive anti-HLA antibodies no longer bind to SLA on the cells of the organ-source pigs. While deletion of SLA expression is possible, it would render the pig at risk for infectious complications. The ideal organ-source pig for HLA highly sensitized recipients may therefore be 1 with site-specific mutations to eliminate cross-reactive binding.
Collapse
Affiliation(s)
- Joseph M Ladowski
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL
| | | | | |
Collapse
|
36
|
Cooper DKC, Hara H, Iwase H, Yamamoto T, Wang ZY, Jagdale A, Bikhet MH, Nguyen HQ, Foote JB, Paris WD, Ayares D, Kumar V, Anderson DJ, Locke JE, Eckhoff DE. Pig kidney xenotransplantation: Progress toward clinical trials. Clin Transplant 2020; 35:e14139. [PMID: 33131148 DOI: 10.1111/ctr.14139] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/09/2020] [Accepted: 10/24/2020] [Indexed: 12/16/2022]
Abstract
Pig organ xenotransplantation offers a solution to the shortage of deceased human organs for transplantation. The pathobiological response to a pig xenograft is complex, involving antibody, complement, coagulation, inflammatory, and cellular responses. To overcome these barriers, genetic manipulation of the organ-source pigs has largely been directed to two major aims-(a) deletion of expression of the known carbohydrate xenoantigens against which humans have natural (preformed) antibodies, and (b) transgenic expression of human protective proteins, for example, complement- and coagulation-regulatory proteins. Conventional (FDA-approved) immunosuppressive therapy is unsuccessful in preventing an adaptive immune response to pig cells, but blockade of the CD40:CD154 costimulation pathway is successful. Survival of genetically engineered pig kidneys in immunosuppressed nonhuman primates can now be measured in months. Non-immunological aspects, for example, pig renal function, a hypovolemia syndrome, and rapid growth of the pig kidney after transplantation, are briefly discussed. We suggest that patients on the wait-list for a deceased human kidney graft who are unlikely to receive one due to long waiting times are those for whom kidney xenotransplantation might first be considered. The potential risk of infection, public attitudes to xenotransplantation, and ethical, regulatory, and financial aspects are briefly addressed.
Collapse
Affiliation(s)
- David K C Cooper
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Hidetaka Hara
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Hayato Iwase
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Takayuki Yamamoto
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Zheng-Yu Wang
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Abhijit Jagdale
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Mohamed H Bikhet
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Huy Q Nguyen
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jeremy B Foote
- Department of Microbiology and Animal Resources Program, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Wayne D Paris
- Department of Social Work, Abilene Christian University, Abilene, TX, USA
| | | | - Vineeta Kumar
- Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Douglas J Anderson
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jayme E Locke
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Devin E Eckhoff
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| |
Collapse
|
37
|
Bikhet M, Morsi M, Hara H, Rhodes LA, Carlo WF, Cleveland D, Cooper DK, Iwase H. The immune system in infants: Relevance to xenotransplantation. Pediatr Transplant 2020; 24:e13795. [PMID: 32845539 PMCID: PMC7606572 DOI: 10.1111/petr.13795] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/10/2020] [Accepted: 06/22/2020] [Indexed: 12/17/2022]
Abstract
Despite the improvement in surgical interventions in the treatment of congenital heart disease, many life-threatening lesions (eg, hypoplastic left heart syndrome) ultimately require transplantation. However, there is a great limitation in the availability of deceased human cardiac donors of a suitable size. Hearts from genetically engineered pigs may provide an alternative source. The relatively immature immune system in infants (eg, absence of anti-carbohydrate antibodies, reduced complement activation, reduced innate immune cell activity) should minimize the risk of early antibody-mediated rejection of a pig graft. Additionally, recipient thymectomy, performed almost routinely as a preliminary to orthotopic heart transplantation in this age-group, impairs the T-cell response. Because of the increasing availability of genetically engineered pigs (eg, triple-knockout pigs that do not express any of the three known carbohydrate antigens against which humans have natural antibodies) and the ability to diagnose congenital heart disease during fetal life, cardiac xenotransplantation could be preplanned to be carried out soon after birth. Because of these several advantages, prolonged graft survival and even the induction of tolerance, for example, following donor-specific pig thymus transplantation, are more likely to be achieved in infants than in adults. In this review, we summarize the factors in the infant immune system that would be advantageous in the success of cardiac xenotransplantation in this age-group.
Collapse
Affiliation(s)
- Mohamed Bikhet
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, AL, USA
| | - Mahmoud Morsi
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, AL, USA
| | - Hidetaka Hara
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, AL, USA
| | - Leslie A. Rhodes
- Division of Pediatric Cardiology, Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Waldemar F. Carlo
- Division of Pediatric Cardiology, Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - David Cleveland
- Department of Pediatric Cardiovascular Surgery, Children’s Hospital of Alabama, Birmingham, AL, USA
| | - David K.C Cooper
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, AL, USA
| | - Hayato Iwase
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, AL, USA
| |
Collapse
|
38
|
Pierson RN, Burdorf L, Madsen JC, Lewis GD, D’Alessandro DA. Pig-to-human heart transplantation: Who goes first? Am J Transplant 2020; 20:2669-2674. [PMID: 32301262 PMCID: PMC9448330 DOI: 10.1111/ajt.15916] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/05/2020] [Accepted: 04/06/2020] [Indexed: 01/25/2023]
Abstract
Cardiac xenotransplantation has recently taken an important step towards clinical reality. In anticipation of the "first-in-human" heart xenotransplantation trial, we propose a set of patient characteristics that define potential candidates. Our premise is that, to be ethically justified, the risks posed by current state-of-the-art options must outweigh the anticipated risks of a pioneering xenotransplant procedure. Suitable candidates include patients who are at high immunologic risk because of sensitization to alloantigens, including those who have exhibited early onset or accelerated cardiac allograft vasculopathy. In addition, patients should be considered (1) for whom mechanical circulatory support would be prohibitively risky due to a hypercoagulable state, a contraindication to anticoagulation, or restrictive physiology; (2) with severe biventricular dysfunction predicting unsuccessful univentricular left heart support; and (3) adults with complex congenital heart disease. In conclusion, because the published preclinical benchmark for clinical translation of heart xenotransplantation appears within reach, carefully and deliberately defining appropriate trial participants is timely as the basis for ethical clinical trial design.
Collapse
Affiliation(s)
- Richard N. Pierson
- Division of Cardiac Surgery, Massachusetts General Hospital, Harvard University, Boston, Massachusetts,Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Harvard University, Boston, Massachusetts
| | - Lars Burdorf
- Division of Cardiac Surgery, Massachusetts General Hospital, Harvard University, Boston, Massachusetts,Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Harvard University, Boston, Massachusetts
| | - Joren C. Madsen
- Division of Cardiac Surgery, Massachusetts General Hospital, Harvard University, Boston, Massachusetts,Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Harvard University, Boston, Massachusetts
| | - Gregory D. Lewis
- Division of Cardiology, Department of Medicine, Massachusetts General Hospital, Harvard University, Boston, Massachusetts
| | - David A. D’Alessandro
- Division of Cardiac Surgery, Massachusetts General Hospital, Harvard University, Boston, Massachusetts
| |
Collapse
|
39
|
Abstract
PURPOSE OF REVIEW To describe the most recent progress towards tolerance in xenotransplantation. RECENT FINDINGS Mixed chimerism and thymic transplantation have been used to promote tolerance in xenotransplantation models. Intra-bone bone marrow transplantation is a recent advance for mixed chimerism, which promotes longer lasting chimerism and early graft function of subsequent organ transplantation. The hybrid thymus, an advancement to the vascularized thymokidney and vascularized thymic lobe, is being developed to allow for both donor and recipient T-cell selection in the chimeric thymus, encouraging tolerance to self and donor while maintaining appropriate immune function. Regulatory T cells show promise to promote tolerance by suppressing effector T cells and by supporting mixed chimerism. Monoclonal antibodies such as anti-CD2 may promote tolerance through suppression of CD2+ effector and memory T cells whereas Tregs, which express lower numbers of CD2, are relatively spared and might be used to promote tolerance. SUMMARY These findings contribute major advances to tolerance in xenotransplantation. A combination of many of these mechanisms will likely be needed to have long-term tolerance maintained without the use of immunosuppression.
Collapse
Affiliation(s)
- Erin M. Duggan
- Columbia Center for Translational Immunology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
- Department of Surgery, Columbia University, New York, NY
| | - Adam Griesemer
- Columbia Center for Translational Immunology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
- Department of Surgery, Columbia University, New York, NY
| |
Collapse
|
40
|
Abstract
PURPOSE OF REVIEW To review the impact of a new technology, 3D-bioprinting, in xenotransplantation research. RECENT FINDINGS Genetically engineered pigs, beginning with human (h) CD55-transgenic and Gal-knockout pigs, have improved the outcomes of xenotransplantation research. Today, there are more than 30 different genetically engineered pigs either expressing human gene(s) or lacking pig gene(s). CRIPSR/cas9 technology has facilitated the production of multigene pigs (up to nine genes in a single pig), which lack multiple pig xenoantigens, and express human transgenes, such as hCD46, hCD55, hThrombomodulin, hCD39, etc. Although recent studies in nonhuman primates (NHPs) have demonstrated prolonged survival after life-supporting pig kidney, heart, and islet xenotransplantation, researchers have difficulty determining the best genetic combination to test in NHPs because of a potential greater than 100 000 genetic combinations. 3D-bioprinting of genetically engineered pig cells: is superior to 2D in-vitro testing, enables organ-specific testing, helps to understand differences in immunogenicity between organs, and is faster and cheaper than testing in NHPs. Moreover, 3D-bioprinted cells can be continuously perfused in a bioreactor, controlling for all variables, except the studied variable. SUMMARY 3D-bioprinting can help in the study of the impact of specific genes (human or pig) in xenotransplantation in a rapid, inexpensive, and reliable way.
Collapse
|
41
|
Maenaka A, Kenta I, Ota A, Miwa Y, Ohashi W, Horimi K, Matsuoka Y, Ohnishi M, Uchida K, Kobayashi T. Interferon-γ-induced HLA Class II expression on endothelial cells is decreased by inhibition of mTOR and HMG-CoA reductase. FEBS Open Bio 2020; 10:927-936. [PMID: 32237049 PMCID: PMC7193171 DOI: 10.1002/2211-5463.12854] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 03/10/2020] [Accepted: 03/26/2020] [Indexed: 12/15/2022] Open
Abstract
In organ transplantation, donor‐specific HLA antibody (DSA) is considered a major cause of graft rejection. Because DSA targets primarily donor‐specific human leukocyte antigen (HLA) expressed on graft endothelial cells, the prevention of its expression is a possible strategy for avoiding or salvaging DSA‐mediated graft rejection. We examined the effect of various clinically used drugs on HLA class II expression on endothelial cells. Interferon‐γ (IFN‐γ)‐induced HLA class II DR (HLA‐DR) was downregulated by everolimus (EVR, 49.1% ± 0.8%; P < 0.01) and fluvastatin (FLU, 33.8% ± 0.6%; P < 0.01). Moreover, the combination of EVR and FLU showed a greater suppressive effect on HLA‐DR expression. In contrast, cyclosporine, tacrolimus, mycophenolic acid, and prednisolone did not exhibit any significant suppressive effect. FLU, but not EVR, suppressed mRNA of HLA‐DR. Imaging analysis revealed that HLA‐DR expressed in cytosol or on the cell surface was repressed by EVR (cytosol: 58.6% ± 4.9%, P < 0.01; cell surface: 80.9% ± 4.0%, P < 0.01) and FLU (cytosol: 19.0% ± 3.4%, P < 0.01; cell surface: 48.3% ± 4.8%, P < 0.01). These data indicated that FLU and EVR suppressed IFN‐γ‐induced HLA‐DR expression at the transcriptional and post‐translational level, respectively, suggesting a potential approach for alleviating DSA‐related issues in organ transplantation.
Collapse
Affiliation(s)
- Akihiro Maenaka
- Department of Pharmacy, Aichi Medical University School of Medicine, Nagakute, Japan.,Department of Renal Transplant Surgery, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Iwasaki Kenta
- Department of Kidney Disease and Transplant Immunology, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Akinobu Ota
- Department of Biochemistry, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Yuko Miwa
- Department of Kidney Disease and Transplant Immunology, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Wataru Ohashi
- Division of Biostatistics, Clinical Research Center, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Kosei Horimi
- Department of Renal Transplant Surgery, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Yutaka Matsuoka
- Department of Renal Transplant Surgery, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Masafumi Ohnishi
- Department of Pharmacy, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Kazuharu Uchida
- Department of Kidney Disease and Transplant Immunology, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Takaaki Kobayashi
- Department of Renal Transplant Surgery, Aichi Medical University School of Medicine, Nagakute, Japan
| |
Collapse
|
42
|
Hein R, Sake HJ, Pokoyski C, Hundrieser J, Brinkmann A, Baars W, Nowak-Imialek M, Lucas-Hahn A, Figueiredo C, Schuberth HJ, Niemann H, Petersen B, Schwinzer R. Triple (GGTA1, CMAH, B2M) modified pigs expressing an SLA class I low phenotype-Effects on immune status and susceptibility to human immune responses. Am J Transplant 2020; 20:988-998. [PMID: 31733031 DOI: 10.1111/ajt.15710] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/07/2019] [Accepted: 11/01/2019] [Indexed: 02/06/2023]
Abstract
Porcine xenografts lacking swine leukocyte antigen (SLA) class I are thought to be protected from human T cell responses. We have previously shown that SLA class I deficiency can be achieved in pigs by CRISPR/Cas9-mediated deletion of β2 -microglobulin (B2M). Here, we characterized another line of genetically modified pigs in which targeting of the B2M locus did not result in complete absence of B2M and SLA class I but rather in significantly reduced expression levels of both molecules. Residual SLA class I was functionally inert, because no proper differentiation of the CD8+ T cell subset was observed in B2Mlow pigs. Cells from B2Mlow pigs were less capable in triggering proliferation of human peripheral blood mononuclear cells in vitro, which was mainly due to the nonresponsiveness of CD8+ T cells. Nevertheless, cytotoxic effector cells developing from unaffected cell populations (eg, CD4+ T cells, natural killer cells) lysed targets from both SLA class I+ wildtype and SLA class Ilow pigs with similar efficiency. These data indicate that the absence of SLA class I is an effective approach to prevent the activation of human CD8+ T cells during the induction phase of an anti-xenograft response. However, cytotoxic activity of cells during the effector phase cannot be controlled by this approach.
Collapse
Affiliation(s)
- Rabea Hein
- Transplant Laboratory, Department of General-, Visceral-, and Transplantation Surgery, Hannover Medical School, Hannover, Germany
| | - Hendrik J Sake
- Department of Biotechnology, Institute of Farm Animal Genetics, Friedrich-Loeffler-Institute, Mariensee, Neustadt, Germany
| | - Claudia Pokoyski
- Transplant Laboratory, Department of General-, Visceral-, and Transplantation Surgery, Hannover Medical School, Hannover, Germany
| | - Joachim Hundrieser
- Transplant Laboratory, Department of General-, Visceral-, and Transplantation Surgery, Hannover Medical School, Hannover, Germany
| | - Antje Brinkmann
- Transplant Laboratory, Department of General-, Visceral-, and Transplantation Surgery, Hannover Medical School, Hannover, Germany
| | - Wiebke Baars
- Transplant Laboratory, Department of General-, Visceral-, and Transplantation Surgery, Hannover Medical School, Hannover, Germany
| | - Monika Nowak-Imialek
- Department of Biotechnology, Institute of Farm Animal Genetics, Friedrich-Loeffler-Institute, Mariensee, Neustadt, Germany
| | - Andrea Lucas-Hahn
- Department of Biotechnology, Institute of Farm Animal Genetics, Friedrich-Loeffler-Institute, Mariensee, Neustadt, Germany
| | | | | | - Heiner Niemann
- Department of Biotechnology, Institute of Farm Animal Genetics, Friedrich-Loeffler-Institute, Mariensee, Neustadt, Germany
| | - Björn Petersen
- Department of Biotechnology, Institute of Farm Animal Genetics, Friedrich-Loeffler-Institute, Mariensee, Neustadt, Germany
| | - Reinhard Schwinzer
- Transplant Laboratory, Department of General-, Visceral-, and Transplantation Surgery, Hannover Medical School, Hannover, Germany
| |
Collapse
|
43
|
Abstract
PURPOSE OF REVIEW The use of genetically modified donor pigs has been integral to recent major advances in xenograft survival in preclinical nonhuman primate models. CRISPR-Cas9 gene editing technology has dramatically accelerated the development of multimodified pigs. This review examines the current and projected impact of CRISPR-Cas9-mediated donor modification on preventing rejection and potentially promoting tolerance of porcine xenografts. RECENT FINDINGS CRISPR-Cas9 has been used to engineer several genetic modifications relevant to xenotransplantation into pigs, including glycosyltransferase knockouts (GGTA1, CMAH, β4GALNT2, A3GALT2 and combinations thereof), other knockouts (SLA-I, ULBP1, PERV and GHR), and one knock-in (anti-CD2 monoclonal antibody transgene knocked into GGTA1). Although the use of these pigs as donors in preclinical nonhuman primate models has been limited to a single study to date, in-vitro analysis of their cells has provided invaluable information. For example, deletion of three of the glycosyltransferases progressively decreased the binding and cytotoxicity of preexisting immunoglobulin G and immunoglobulin M in human sera, suggesting that this 'triple-KO' pig could be a platform for clinical xenotransplantation. SUMMARY CRISPR-Cas9 enables the rapid generation of gene-edited pigs containing multiple tailored genetic modifications that are anticipated to have a positive impact on the efficacy and safety of pig-to-human xenotransplantation.
Collapse
|
44
|
Abstract
There is a well-known worldwide shortage of deceased human donor organs for clinical transplantation. The transplantation of organs from genetically engineered pigs may prove an alternative solution. In the past 5 years, there have been sequential advances that have significantly increased pig graft survival in nonhuman primates. This progress has been associated with (1) the availability of increasingly sophisticated genetically engineered pigs; (2) the introduction of novel immunosuppressive agents, particularly those that block the second T-cell signal (costimulation blockade); (3) a better understanding of the inflammatory response to pig xenografts; and (4) increasing experience in the management of nonhuman primates with pig organ or cell grafts. The range of investigations required in experimental studies has increased. The standard immunologic assays are still carried out, but increasingly investigations aimed toward other pathobiologic barriers (e.g., coagulation dysregulation and inflammation) have become more important in determining injury to the graft.Now that prolonged graft survival, extending to months or even years, is increasingly being obtained, the function of the grafts can be more reliably assessed. If the source pigs are bred and housed under biosecure isolation conditions, and weaned early from the sow, most microorganisms can be eradicated from the herd. The potential risk of porcine endogenous retrovirus (PERV) infection remains unknown, but is probably small. Attention is being directed toward the selection of patients for the first clinical trials of xenotransplantation.
Collapse
Affiliation(s)
- David K C Cooper
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA.
| |
Collapse
|
45
|
Hammer SE, Ho CS, Ando A, Rogel-Gaillard C, Charles M, Tector M, Tector AJ, Lunney JK. Importance of the Major Histocompatibility Complex (Swine Leukocyte Antigen) in Swine Health and Biomedical Research. Annu Rev Anim Biosci 2019; 8:171-198. [PMID: 31846353 DOI: 10.1146/annurev-animal-020518-115014] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In pigs, the major histocompatibility complex (MHC), or swine leukocyte antigen (SLA) complex, maps to Sus scrofa chromosome 7. It consists of three regions, the class I and class III regions mapping to 7p1.1 and the class II region mapping to 7q1.1. The swine MHC is divided by the centromere, which is unique among mammals studied to date. The SLA complexspans between 2.4 and 2.7 Mb, depending on haplotype, and encodes approximately 150 loci, with at least 120 genes predicted to be functional. Here we update the whole SLA complex based on the Sscrofa11.1 build and annotate the organization for all recognized SLA genes and their allelic sequences. We present SLA nomenclature and typing methods and discuss the expression of SLA proteins, as well as their role in antigen presentation and immune, disease, and vaccine responses. Finally, we explore the role of SLA genes in transplantation and xenotransplantation and their importance in swine biomedical models.
Collapse
Affiliation(s)
- Sabine E Hammer
- Institute of Immunology, Department of Pathobiology, University of Veterinary Medicine Vienna, A-1210 Vienna, Austria
| | - Chak-Sum Ho
- Gift of Hope Organ & Tissue Donor Network, Itasca, Illinois 60143, USA
| | - Asako Ando
- Department of Molecular Life Science, Division of Basic Medical Science and Molecular Medicine, Tokai University School of Medicine, Isehara 259-1193, Japan
| | | | - Mathieu Charles
- GABI, INRA, AgroParisTech, Université Paris-Saclay, 78350 Jouy-en-Josas, France
| | - Matthew Tector
- Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA.,Current address: Makana Therapeutics, Wilmington, Delaware 19801, USA
| | - A Joseph Tector
- Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA.,Current address: Department of Surgery, University of Miami, Miami, Florida 33136, USA
| | - Joan K Lunney
- Animal Parasitic Diseases Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, US Department of Agriculture, Beltsville, Maryland 20705, USA;
| |
Collapse
|
46
|
Cooper DKC, Hara H, Iwase H, Yamamoto T, Jagdale A, Kumar V, Mannon RB, Hanaway MJ, Anderson DJ, Eckhoff DE. Clinical Pig Kidney Xenotransplantation: How Close Are We? J Am Soc Nephrol 2019; 31:12-21. [PMID: 31792154 DOI: 10.1681/asn.2019070651] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Patients with ESKD who would benefit from a kidney transplant face a critical and continuing shortage of kidneys from deceased human donors. As a result, such patients wait a median of 3.9 years to receive a donor kidney, by which time approximately 35% of transplant candidates have died while waiting or have been removed from the waiting list. Those of blood group B or O may experience a significantly longer waiting period. This problem could be resolved if kidneys from genetically engineered pigs offered an alternative with an acceptable clinical outcome. Attempts to accomplish this have followed two major paths: deletion of pig xenoantigens, as well as insertion of "protective" human transgenes to counter the human immune response. Pigs with up to nine genetic manipulations are now available. In nonhuman primates, administering novel agents that block the CD40/CD154 costimulation pathway, such as an anti-CD40 mAb, suppresses the adaptive immune response, leading to pig kidney graft survival of many months without features of rejection (experiments were terminated for infectious complications). In the absence of innate and adaptive immune responses, the transplanted pig kidneys have generally displayed excellent function. A clinical trial is anticipated within 2 years. We suggest that it would be ethical to offer a pig kidney transplant to selected patients who have a life expectancy shorter than the time it would take for them to obtain a kidney from a deceased human donor. In the future, the pigs will also be genetically engineered to control the adaptive immune response, thus enabling exogenous immunosuppressive therapy to be significantly reduced or eliminated.
Collapse
Affiliation(s)
| | - Hidetaka Hara
- Division of Transplantation, Department of Surgery and
| | - Hayato Iwase
- Division of Transplantation, Department of Surgery and
| | | | | | - Vineeta Kumar
- Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Roslyn Bernstein Mannon
- Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | | | | | | |
Collapse
|
47
|
Forneris N, Levy H, Burlak C. Xenotransplantation literature update, July/August 2019. Xenotransplantation 2019; 26:e12561. [PMID: 31562656 DOI: 10.1111/xen.12561] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 09/18/2019] [Indexed: 12/31/2022]
Affiliation(s)
- Nicole Forneris
- Department of Surgery, University of Minnesota Medical School, Minneapolis, MN, USA
| | - Heather Levy
- Department of Surgery, University of Minnesota Medical School, Minneapolis, MN, USA
| | - Christopher Burlak
- Department of Surgery, University of Minnesota Medical School, Minneapolis, MN, USA
| |
Collapse
|
48
|
Abstract
OBJECTIVE Xenotransplantation using pig organs could end the donor organ shortage for transplantation, but humans have xenoreactive antibodies that cause early graft rejection. Genome editing can eliminate xenoantigens in donor pigs to minimize the impact of these xenoantibodies. Here we determine whether an improved cross-match and chemical immunosuppression could result in prolonged kidney xenograft survival in a pig-to-rhesus preclinical model. METHODS Double xenoantigen (Gal and Sda) knockout (DKO) pigs were created using CRISPR/Cas. Serum from rhesus monkeys (n = 43) was cross-matched with cells from the DKO pigs. Kidneys from the DKO pigs were transplanted into rhesus monkeys (n = 6) that had the least reactive cross-matches. The rhesus recipients were immunosuppressed with anti-CD4 and anti-CD8 T-cell depletion, anti-CD154, mycophenolic acid, and steroids. RESULTS Rhesus antibody binding to DKO cells is reduced, but all still have positive CDC and flow cross-match. Three grafts were rejected early at 5, 6, and 6 days. Longer survival was achieved in recipients with survival to 35, 100, and 435 days. Each of the 3 early graft losses was secondary to IgM antibody-mediated rejection. The 435-day graft loss occurred secondary to IgG antibody-mediated rejection. CONCLUSIONS Reducing xenoantigens in donor pigs and chemical immunosuppression can be used to achieve prolonged renal xenograft survival in a preclinical model, suggesting that if a negative cross-match can be obtained for humans then prolonged survival could be achieved.
Collapse
|
49
|
Xie C, Qu Z, Hara H, Dai W, Wang X, Pan D, Zhou M, Dai Y, Cai Z, Zhang J, Cooper DKC, Mou L. Downregulation of Gabarapl1 significantly attenuates antibody binding to porcine aortic endothelial cells. Xenotransplantation 2019; 26:e12537. [PMID: 31433094 DOI: 10.1111/xen.12537] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 05/03/2019] [Accepted: 05/22/2019] [Indexed: 12/22/2022]
Affiliation(s)
- Chongwei Xie
- Institute of Translational Medicine, Shenzhen Second People's Hospital School of Medicine of Shenzhen University Shenzhen China
- Medical Research Center Yuebei People's Hospital Shaoguan China
- Institute of Immunology, Zhongshan School of Medicine Sun Yat‐sen University Guangzhou China
| | - Zepeng Qu
- Institute of Translational Medicine, Shenzhen Second People's Hospital School of Medicine of Shenzhen University Shenzhen China
| | - Hidetaka Hara
- Xenotransplantation Program, Department of Surgery The University of Alabama at Birmingham Birmingham Alabama
| | - Wenjie Dai
- Institute of Translational Medicine, Shenzhen Second People's Hospital School of Medicine of Shenzhen University Shenzhen China
| | - Xiliang Wang
- Institute of Translational Medicine, Shenzhen Second People's Hospital School of Medicine of Shenzhen University Shenzhen China
| | - Dengke Pan
- Key Laboratory of Farm Animal Genetic Resource and Germplasm Innovation of Ministry of Agriculture, Institute of Animal Science Chinese Academy of Agricultural Sciences Beijing China
| | - Ming Zhou
- Institute of Translational Medicine, Shenzhen Second People's Hospital School of Medicine of Shenzhen University Shenzhen China
| | - Yifan Dai
- Jiangsu Key Laboratory of Xenotransplantation Nanjing Medical University Nanjing China
| | - Zhiming Cai
- Institute of Translational Medicine, Shenzhen Second People's Hospital School of Medicine of Shenzhen University Shenzhen China
| | - Junfang Zhang
- College of Life Science and Oceanography Shenzhen University Shenzhen China
| | - David K. C. Cooper
- Xenotransplantation Program, Department of Surgery The University of Alabama at Birmingham Birmingham Alabama
| | - Lisha Mou
- Shenzhen Xenotransplantation Research and Development Center, Institute of Translational Medicine Shenzhen Second People's Hospital Shenzhen China
| |
Collapse
|
50
|
Ladowski JM, Martens GR, Reyes LM, Hauptfeld-Dolejsek V, Tector M, Tector J. Examining epitope mutagenesis as a strategy to reduce and eliminate human antibody binding to class II swine leukocyte antigens. Immunogenetics 2019; 71:479-487. [PMID: 31270568 DOI: 10.1007/s00251-019-01123-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 06/14/2019] [Indexed: 11/26/2022]
Abstract
Xenotransplantation of pig organs into people may help alleviate the critical shortage of donors which faces organ transplantation. Unfortunately, human antibodies vigorously attack pig tissues preventing the clinical application of xenotransplantation. The swine leukocyte antigens (SLA), homologs of human HLA molecules, can be xenoantigens. SLA molecules, encoded by genes in the pig major histocompatibility complex, contribute to protective immune responses in pig. Therefore, simply inactivating them through genome engineering could reduce the ability of the human immune system to surveil transplanted pig organs for infectious disease or the development of neoplasms. A potential solution to this problem is to identify and modify epitopes in SLA proteins to eliminate their contribution to humoral xenoantigenicity while retaining their biosynthetic competence and ability to contribute to protective immunity. We previously showed that class II SLA proteins were recognized as xenoantigens and mutating arginine at position 55 to proline, in an SLA-DQ beta chain, could reduce human antibody binding. Here, we extend these observations by creating several additional point mutants at position 55. Using a panel of monoclonal antibodies specific for class II SLA proteins, we show that these mutants remain biosynthetically competent. Examining antibody binding to these variants shows that point mutagenesis can reduce, eliminate, or increase antibody binding to class II SLA proteins. Individual mutations can have opposite effects on antibody binding when comparing samples from different people. We also performed a preliminary analysis of creating point mutants near to position 55 to demonstrate that manipulating additional residues also affects antibody reactivity.
Collapse
Affiliation(s)
- Joseph M Ladowski
- Department of Surgery, University of Alabama at Birmingham, ZRB 701, 1720 2nd Ave South, Birmingham, AL, 35294, USA
| | - Gregory R Martens
- Department of Surgery, University of Alabama at Birmingham, ZRB 701, 1720 2nd Ave South, Birmingham, AL, 35294, USA
| | - Luz M Reyes
- Department of Surgery, University of Alabama at Birmingham, ZRB 701, 1720 2nd Ave South, Birmingham, AL, 35294, USA
| | - Vera Hauptfeld-Dolejsek
- Department of Surgery, University of Alabama at Birmingham, ZRB 701, 1720 2nd Ave South, Birmingham, AL, 35294, USA
- Transplant Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Matthew Tector
- Department of Surgery, University of Alabama at Birmingham, ZRB 701, 1720 2nd Ave South, Birmingham, AL, 35294, USA
- Transplant Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Joseph Tector
- Department of Surgery, University of Alabama at Birmingham, ZRB 701, 1720 2nd Ave South, Birmingham, AL, 35294, USA.
- Transplant Surgery, University of Alabama at Birmingham, Birmingham, AL, USA.
| |
Collapse
|