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Köhne M, Diel E, Packeiser EM, Böttcher D, Tönissen A, Unruh C, Goericke-Pesch S, Ulrich R, Sieme H. Analysis of gene and protein expression in the endometrium for validation of an ex vivo model of the equine uterus using PCR, digital and visual histopathology. Theriogenology 2024; 221:38-46. [PMID: 38537320 DOI: 10.1016/j.theriogenology.2024.03.015] [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: 01/03/2024] [Revised: 03/21/2024] [Accepted: 03/23/2024] [Indexed: 04/09/2024]
Abstract
In the past, most research in equine reproduction has been performed in vivo but the use of in vitro and ex vivo models has recently increased. This study aimed to evaluate the functional stability of an ex vivo hemoperfused model for equine uteri with molecular characterization of marker genes and their proteins. In addition, the study validated the respective protein expression and the aptness of the software QuPath for identifying and scoring immunohistochemically stained equine endometrium. After collection, uteri (n = 12) were flushed with preservation solution, transported to the laboratory on ice, and perfused with autologous blood for 6 h. Cycle stage was determined by examination of the ovaries for presence of Graafian follicles or corpora lutea and analysis of plasma progesterone concentration (estrus: n = 4; diestrus: n = 4; anestrus: n = 4). Samples were obtained directly after slaughter, after transportation, and during perfusion (240, 300, 360 min). mRNA expression levels of progesterone (PGR), estrogen (ESR1) and oxytocin (OXTR) receptor as well as of MKI67 (marker of cell growth) and CASP3 (marker of apoptosis) were analyzed by RT-qPCR, and correlation to protein abundance was validated by immunohistochemical staining. Endometrial samples were analyzed by visual and computer-assisted evaluation of stained antigens via QuPath. For PGR, effects of the perfusion and cycle stage on expression were found (P < 0.05), while ESR1 was affected only by cycle stage (P < 0.05) and OXTR was unaffected by perfusion and cycle stage. MKI67 was lower after 360 min of perfusion as compared to samples collected before perfusion (P < 0.05). For CASP3, differences in gene expression were found after transport and samples taken after 240 min (P < 0.05). Immunohistochemical staining revealed effects of perfusion on stromal and glandular cells for steroid hormone receptors, but not for Ki-67 and active Caspase 3. OXTR was visualized in all layers of the endometrium and was unaffected by perfusion. Comparison of QuPath and visual analysis resulted in similar results. For most cell types and stained antigens, the correlation coefficient was r > 0.5. In conclusion, the isolated hemoperfused model of the equine uterus was successfully validated at the molecular level, demonstrating stability of key marker gene expression. The utility of computer-assisted immunohistochemical analysis of equine endometrial samples was also confirmed.
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Affiliation(s)
- Martin Köhne
- Unit for Reproductive Medicine, Clinic for Horses, University of Veterinary Medicine, Foundation, 30559, Hannover, Germany.
| | - Emilia Diel
- Unit for Reproductive Medicine, Clinic for Horses, University of Veterinary Medicine, Foundation, 30559, Hannover, Germany
| | - Eva-Maria Packeiser
- Unit for Reproductive Medicine, Clinic for Small Animals, University of Veterinary Medicine, Foundation, 30559, Hannover, Germany
| | - Denny Böttcher
- Institute of Veterinary Pathology, Faculty of Veterinary Medicine, Leipzig University, 04103, Leipzig, Germany
| | - Anna Tönissen
- Unit for Reproductive Medicine, Clinic for Horses, University of Veterinary Medicine, Foundation, 30559, Hannover, Germany
| | - Christin Unruh
- Unit for Reproductive Medicine, Clinic for Horses, University of Veterinary Medicine, Foundation, 30559, Hannover, Germany
| | - Sandra Goericke-Pesch
- Unit for Reproductive Medicine, Clinic for Small Animals, University of Veterinary Medicine, Foundation, 30559, Hannover, Germany
| | - Reiner Ulrich
- Institute of Veterinary Pathology, Faculty of Veterinary Medicine, Leipzig University, 04103, Leipzig, Germany
| | - Harald Sieme
- Unit for Reproductive Medicine, Clinic for Horses, University of Veterinary Medicine, Foundation, 30559, Hannover, Germany
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2
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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.
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Affiliation(s)
| | - Xiaozhou He
- Urology Department, Third Affiliated Hospital of Soochow University, Changzhou, China
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3
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Moazami N, Stern JM, Khalil K, Kim JI, Narula N, Mangiola M, Weldon EP, Kagermazova L, James L, Lawson N, Piper GL, Sommer PM, Reyentovich A, Bamira D, Saraon T, Kadosh BS, DiVita M, Goldberg RI, Hussain ST, Chan J, Ngai J, Jan T, Ali NM, Tatapudi VS, Segev DL, Bisen S, Jaffe IS, Piegari B, Kowalski H, Kokkinaki M, Monahan J, Sorrells L, Burdorf L, Boeke JD, Pass H, Goparaju C, Keating B, Ayares D, Lorber M, Griesemer A, Mehta SA, Smith DE, Montgomery RA. Pig-to-human heart xenotransplantation in two recently deceased human recipients. Nat Med 2023; 29:1989-1997. [PMID: 37488288 DOI: 10.1038/s41591-023-02471-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 06/26/2023] [Indexed: 07/26/2023]
Abstract
Genetically modified xenografts are one of the most promising solutions to the discrepancy between the numbers of available human organs for transplantation and potential recipients. To date, a porcine heart has been implanted into only one human recipient. Here, using 10-gene-edited pigs, we transplanted porcine hearts into two brain-dead human recipients and monitored xenograft function, hemodynamics and systemic responses over the course of 66 hours. Although both xenografts demonstrated excellent cardiac function immediately after transplantation and continued to function for the duration of the study, cardiac function declined postoperatively in one case, attributed to a size mismatch between the donor pig and the recipient. For both hearts, we confirmed transgene expression and found no evidence of cellular or antibody-mediated rejection, as assessed using histology, flow cytometry and a cytotoxic crossmatch assay. Moreover, we found no evidence of zoonotic transmission from the donor pigs to the human recipients. While substantial additional work will be needed to advance this technology to human trials, these results indicate that pig-to-human heart xenotransplantation can be performed successfully without hyperacute rejection or zoonosis.
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Affiliation(s)
- Nader Moazami
- Department of Cardiothoracic Surgery, New York University Langone Health, New York, NY, USA.
| | - Jeffrey M Stern
- New York University Langone Transplant Institute, New York, NY, USA
| | - Karen Khalil
- New York University Langone Transplant Institute, New York, NY, USA
| | - Jacqueline I Kim
- New York University Langone Transplant Institute, New York, NY, USA
| | - Navneet Narula
- Department of Pathology, New York University Langone Health, New York, NY, USA
| | - Massimo Mangiola
- New York University Langone Transplant Institute, New York, NY, USA
| | - Elaina P Weldon
- New York University Langone Transplant Institute, New York, NY, USA
| | - Larisa Kagermazova
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, USA
| | - Les James
- Department of Cardiothoracic Surgery, New York University Langone Health, New York, NY, USA
| | - Nikki Lawson
- New York University Langone Transplant Institute, New York, NY, USA
| | - Greta L Piper
- Department of Surgery, New York University Langone Health, New York, NY, USA
| | - Philip M Sommer
- Department of Anesthesiology, New York University Langone Health, New York, NY, USA
| | - Alex Reyentovich
- Division of Cardiology, New York University Langone Health, New York, NY, USA
| | - Daniel Bamira
- Division of Cardiology, New York University Langone Health, New York, NY, USA
| | - Tajinderpal Saraon
- Division of Cardiology, New York University Langone Health, New York, NY, USA
| | - Bernard S Kadosh
- Division of Cardiology, New York University Langone Health, New York, NY, USA
| | - Michael DiVita
- Division of Cardiology, New York University Langone Health, New York, NY, USA
| | - Randal I Goldberg
- Division of Cardiology, New York University Langone Health, New York, NY, USA
| | - Syed T Hussain
- Department of Cardiothoracic Surgery, New York University Langone Health, New York, NY, USA
| | - Justin Chan
- Department of Cardiothoracic Surgery, New York University Langone Health, New York, NY, USA
| | - Jennie Ngai
- Department of Anesthesiology, New York University Langone Health, New York, NY, USA
| | - Thomas Jan
- Department of Anesthesiology, New York University Langone Health, New York, NY, USA
| | - Nicole M Ali
- New York University Langone Transplant Institute, New York, NY, USA
| | | | - Dorry L Segev
- Department of Surgery, New York University Langone Health, New York, NY, USA
- Department of Population Health, New York University Grossman School of Medicine, New York, NY, USA
| | - Shivani Bisen
- New York University Grossman School of Medicine, New York University, New York, NY, USA
| | - Ian S Jaffe
- New York University Grossman School of Medicine, New York University, New York, NY, USA
| | - Benjamin Piegari
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Haley Kowalski
- New York University Grossman School of Medicine, New York University, New York, NY, USA
| | | | | | | | | | - Jef D Boeke
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, USA
- Institute for Systems Genetics, New York University Grossman School of Medicine, New York, NY, USA
| | - Harvey Pass
- Department of Cardiothoracic Surgery, New York University Langone Health, New York, NY, USA
| | - Chandra Goparaju
- Department of Cardiothoracic Surgery, New York University Langone Health, New York, NY, USA
| | - Brendan Keating
- Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Marc Lorber
- United Therapeutics Corporation, Silver Spring, MD, USA
| | - Adam Griesemer
- New York University Langone Transplant Institute, New York, NY, USA
| | - Sapna A Mehta
- New York University Langone Transplant Institute, New York, NY, USA
| | - Deane E Smith
- Department of Cardiothoracic Surgery, New York University Langone Health, New York, NY, USA
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Chaban R, Cooper DKC, Pierson RN. Pig heart and lung xenotransplantation: Present status. J Heart Lung Transplant 2022; 41:1014-1022. [PMID: 35659792 PMCID: PMC10124776 DOI: 10.1016/j.healun.2022.04.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 04/14/2022] [Accepted: 04/24/2022] [Indexed: 11/19/2022] Open
Abstract
The recent pig heart transplant in a patient at the University of Maryland Medical Center has stimulated renewed interest in the xenotransplantation of organs from genetically engineered pigs. The barriers to the use of pigs as sources of organs have largely been overcome by 2 approaches - (1) the deletion of expression of the three known pig carbohydrate xenoantigens against which humans have preformed antibodies, and (2) the transgenic introduction of human 'protective' proteins, such as complement-regulatory proteins. These gene modifications, coupled with immunosuppressive therapy based on blockade of the CD40/CD154 costimulation pathway, have resulted in survival of baboons with life-supporting pig heart grafts for almost 9 months. The initial clinical success at the University of Maryland reinforces encouraging preclinical results. It suggests that pig hearts are likely to provide an effective bridge to an allotransplant, but their utility for destination therapy remains uncertain. Because of additional complex immunobiological problems, the same approach has been less successful in preclinical lung xenograft transplantation, where survival is still measured in days or weeks. The first formal clinical trials of pig heart transplantation may include patients who do not have access to an allotransplant, those with contraindications for mechanical circulatory support, those in need of retransplantation or with a high level of panel-reactive antibodies. Infants with complex congenital heart disease, should also be considered.
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Affiliation(s)
- Ryan Chaban
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; Department of Cardiovascular Surgery, University Hospital of Johannes Gutenberg University, Mainz, Germany.
| | - David K C Cooper
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Richard N Pierson
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
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5
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Signaling cascades in the failing heart and emerging therapeutic strategies. Signal Transduct Target Ther 2022; 7:134. [PMID: 35461308 PMCID: PMC9035186 DOI: 10.1038/s41392-022-00972-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/13/2022] [Accepted: 03/20/2022] [Indexed: 12/11/2022] Open
Abstract
Chronic heart failure is the end stage of cardiac diseases. With a high prevalence and a high mortality rate worldwide, chronic heart failure is one of the heaviest health-related burdens. In addition to the standard neurohormonal blockade therapy, several medications have been developed for chronic heart failure treatment, but the population-wide improvement in chronic heart failure prognosis over time has been modest, and novel therapies are still needed. Mechanistic discovery and technical innovation are powerful driving forces for therapeutic development. On the one hand, the past decades have witnessed great progress in understanding the mechanism of chronic heart failure. It is now known that chronic heart failure is not only a matter involving cardiomyocytes. Instead, chronic heart failure involves numerous signaling pathways in noncardiomyocytes, including fibroblasts, immune cells, vascular cells, and lymphatic endothelial cells, and crosstalk among these cells. The complex regulatory network includes protein-protein, protein-RNA, and RNA-RNA interactions. These achievements in mechanistic studies provide novel insights for future therapeutic targets. On the other hand, with the development of modern biological techniques, targeting a protein pharmacologically is no longer the sole option for treating chronic heart failure. Gene therapy can directly manipulate the expression level of genes; gene editing techniques provide hope for curing hereditary cardiomyopathy; cell therapy aims to replace dysfunctional cardiomyocytes; and xenotransplantation may solve the problem of donor heart shortages. In this paper, we reviewed these two aspects in the field of failing heart signaling cascades and emerging therapeutic strategies based on modern biological techniques.
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Pierson RN, Fishman JA, Lewis GD, D'Alessandro DA, Connolly MR, Burdorf L, Madsen JC, Azimzadeh AM. Progress Toward Cardiac Xenotransplantation. Circulation 2020; 142:1389-1398. [PMID: 33017208 DOI: 10.1161/circulationaha.120.048186] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Consistent survival of life-supporting pig heart xenograft recipients beyond 90 days was recently reported using genetically modified pigs and a clinically applicable drug treatment regimen. If this remarkable achievement proves reproducible, published benchmarks for clinical translation of cardiac xenografts appear to be within reach. Key mechanistic insights are summarized here that informed recent pig design and therapeutic choices, which together appear likely to enable early clinical translation.
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Affiliation(s)
- Richard N Pierson
- Division of Cardiac Surgery, Department of Surgery (R.N.P., D.A.D., M.R.C., L.B., J.C.M., A.M.A.), Massachusetts General Hospital and Harvard University, Boston.,Center for Transplantation Sciences (R.N.P., J.A.F., M.R.C., L.B., J.C.M., A.M.A.), Massachusetts General Hospital and Harvard University, Boston
| | - Jay A Fishman
- Center for Transplantation Sciences (R.N.P., J.A.F., M.R.C., L.B., J.C.M., A.M.A.), Massachusetts General Hospital and Harvard University, Boston
| | - Gregory D Lewis
- Division of Cardiology, Department of Medicine (G.D.L.), Massachusetts General Hospital and Harvard University, Boston
| | - David A D'Alessandro
- Division of Cardiac Surgery, Department of Surgery (R.N.P., D.A.D., M.R.C., L.B., J.C.M., A.M.A.), Massachusetts General Hospital and Harvard University, Boston
| | - Margaret R Connolly
- Division of Cardiac Surgery, Department of Surgery (R.N.P., D.A.D., M.R.C., L.B., J.C.M., A.M.A.), Massachusetts General Hospital and Harvard University, Boston.,Center for Transplantation Sciences (R.N.P., J.A.F., M.R.C., L.B., J.C.M., A.M.A.), Massachusetts General Hospital and Harvard University, Boston
| | - Lars Burdorf
- Division of Cardiac Surgery, Department of Surgery (R.N.P., D.A.D., M.R.C., L.B., J.C.M., A.M.A.), Massachusetts General Hospital and Harvard University, Boston.,Center for Transplantation Sciences (R.N.P., J.A.F., M.R.C., L.B., J.C.M., A.M.A.), Massachusetts General Hospital and Harvard University, Boston
| | - Joren C Madsen
- Division of Cardiac Surgery, Department of Surgery (R.N.P., D.A.D., M.R.C., L.B., J.C.M., A.M.A.), Massachusetts General Hospital and Harvard University, Boston.,Center for Transplantation Sciences (R.N.P., J.A.F., M.R.C., L.B., J.C.M., A.M.A.), Massachusetts General Hospital and Harvard University, Boston
| | - Agnes M Azimzadeh
- Division of Cardiac Surgery, Department of Surgery (R.N.P., D.A.D., M.R.C., L.B., J.C.M., A.M.A.), Massachusetts General Hospital and Harvard University, Boston.,Center for Transplantation Sciences (R.N.P., J.A.F., M.R.C., L.B., J.C.M., A.M.A.), Massachusetts General Hospital and Harvard University, Boston
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7
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Liu Z, Hu W, He T, Dai Y, Hara H, Bottino R, Cooper DKC, Cai Z, Mou L. Pig-to-Primate Islet Xenotransplantation: Past, Present, and Future. Cell Transplant 2017; 26:925-947. [PMID: 28155815 PMCID: PMC5657750 DOI: 10.3727/096368917x694859] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 03/21/2017] [Indexed: 12/17/2022] Open
Abstract
Islet allotransplantation results in increasing success in treating type 1 diabetes, but the shortage of deceased human donor pancreata limits progress. Islet xenotransplantation, using pigs as a source of islets, is a promising approach to overcome this limitation. The greatest obstacle is the primate immune/inflammatory response to the porcine (pig) islets, which may take the form of rapid early graft rejection (the instant blood-mediated inflammatory reaction) or T-cell-mediated rejection. These problems are being resolved by the genetic engineering of the source pigs combined with improved immunosuppressive therapy. The results of pig-to-diabetic nonhuman primate islet xenotransplantation are steadily improving, with insulin independence being achieved for periods >1 year. An alternative approach is to isolate islets within a micro- or macroencapsulation device aimed at protecting them from the human recipient's immune response. Clinical trials using this approach are currently underway. This review focuses on the major aspects of pig-to-primate islet xenotransplantation and its potential for treatment of type 1 diabetes.
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Affiliation(s)
- Zhengzhao Liu
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center, Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen, Guangdong, P.R. China
| | - Wenbao Hu
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center, Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen, Guangdong, P.R. China
| | - Tian He
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center, Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen, Guangdong, P.R. China
| | - Yifan Dai
- Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Nanjing, Jiangsu, P.R. China
| | - Hidetaka Hara
- Xenotransplantation Program/Department of Surgery, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Rita Bottino
- Institute for Cellular Therapeutics, Allegheny-Singer Research Institute, Pittsburgh, PA, USA
| | - David K. C. Cooper
- Xenotransplantation Program/Department of Surgery, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Zhiming Cai
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center, Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen, Guangdong, P.R. China
| | - Lisha Mou
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center, Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen, Guangdong, P.R. China
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Complement Regulation and the Host Response to Infection. Xenotransplantation 2014. [DOI: 10.1128/9781555818043.ch8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Membrane-bound complement regulatory proteins as biomarkers and potential therapeutic targets for SLE. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 735:55-81. [PMID: 23402019 DOI: 10.1007/978-1-4614-4118-2_4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
For the last two decades, there had been remarkable advancement in understanding the role of complement regulatory proteins in autoimmune disorders and importance of complement inhibitors as therapeutics. Systemic lupus erythematosus is a prototype of systemic autoimmune disorders. The disease, though rare, is potentially fatal and afflicts women at their reproductive age. It is a complex disease with multiorgan involvement, and each patient presents with a different set of symptoms. The diagnosis is often difficult and is based on the diagnostic criteria set by the American Rheumatology Association. Presence of antinuclear antibodies and more specifically antidouble-stranded DNA indicates SLE. Since the disease is multifactorial and its phenotypes are highly heterogeneous, there is a need to identify multiple noninvasive biomarkers for SLE. Lack of validated biomarkers for SLE disease activity or response to treatment is a barrier to the efficient management of the disease, drug discovery, as well as development of new therapeutics. Recent studies with gene knockout mice have suggested that membrane-bound complement regulatory proteins (CRPs) may critically determine the sensitivity of host tissues to complement injury in autoimmune and inflammatory disorders. Case-controlled and followup studies carried out in our laboratory suggest an intimate relation between the level of DAF, MCP, CR1, and CD59 transcripts and the disease activity in SLE. Based on comparative evaluation of our data on these four membrane-bound complement regulatory proteins, we envisaged CR1 and MCP transcripts as putative noninvasive disease activity markers and the respective proteins as therapeutic targets for SLE. Following is a brief appraisal on membrane-bound complement regulatory proteins DAF, MCP, CR1, and CD59 as biomarkers and therapeutic targets for SLE.
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Dalmasso AP. On the intersections of basic and applied research in xenotransplantation. Xenotransplantation 2012; 19:137-43. [PMID: 22702465 DOI: 10.1111/j.1399-3089.2012.00703.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
I am very grateful to the Council and members of the International Xenotransplantation Association for this Honorary Membership. In accepting this prestigious award, I pay tribute to my mentors Antonio Oriol i Anguera, Carlos Martinez, Robert A. Good, and Hans Müller-Eberhard for their guidance and friendship as I was beginning my travels in biomedical research. I also thank the many gifted collaborators, students, and technical personnel, as well as the agencies and taxpayers, who funded our research and made our scientific contributions possible. Here I briefly mention some of these contributions, including early work on the immunobiology of the thymus, my short incursion in the immunology of Chagas disease, and what have been the dominant themes of my career: the mechanisms of complement injury, the role of complement in pathophysiology, and induction of cytoprotection in the vascular endothelium. I emphasize our contributions on the role of complement as related to understanding and overcoming xenograft injury, a work that has been personally very rewarding. Now it is exciting to see that the field of xenotransplantation research is moving forward vigorously, a time of great optimism suggesting that many potential clinical applications of xenotransplantation will come to fruition in the near future.
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Affiliation(s)
- Agustin P Dalmasso
- Departments of Surgery and of Laboratory Medicine and Pathology, School of Medicine, University of Minnesota, Minneapolis, MN 55455, USA.
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Upregulation of CD59: potential mechanism of accommodation in a large animal model. Transplantation 2009; 87:1308-17. [PMID: 19424030 DOI: 10.1097/tp.0b013e3181a19afc] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND Survival of ABO-mismatched kidneys with stable renal function despite the persistence of anti-ABO antibodies is called accommodation. The mechanism of accommodation is unclear, but may involve complement regulatory proteins such as CD59. The development of alpha-1,3-galactosyltransferase knock-out (GalT-KO) swine that produce anti-Gal antibodies provides a large animal model capable of determining the role of complement regulatory proteins in accommodation. METHODS ELISA and antibody fluorescence-activated cell sorting were used to examine the rate of anti-Gal antibody expression as a function of age. Major histocompatibility complex-matched kidneys were transplanted from Gal-positive MGH miniature swine to MGH GalT-KO swine with systemic immunosuppression. One recipient underwent adsorbtion of anti-Gal antibodies before transplantation. Graft survival, antibody, and complement deposition patterns and CD59 expression were determined. RESULTS Three animals rejected Gal-positive kidneys by humoral mechanisms. One animal with low titers of anti-Gal antibody displayed spontaneous accommodation and the animal that was treated with antibody adsorbtion also displayed accommodation. Rejected grafts had deposition of IgM, IgG, C3, and C5b-9 with low expression of CD59, whereas accommodated grafts had low deposition of C5b-9 and high expression of CD59. Retransplantation of one accommodated graft to a naïve GalT-KO animal confirmed that changes in the graft were responsible for the lack of C5b-9 deposition. CONCLUSION GalT-KO miniature swine produce anti-Gal antibodies and titers increase with age. These anti-Gal antibodies can cause rejection of major histocompatibility complex-matched kidneys unless accommodation occurs. CD59 up-regulation seems to be involved in the mechanism of accommodation by preventing the formation of the membrane attack complex (MAC) on the accommodated graft.
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13
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Layton DS, Bean AG, Dodge NM, Strom ADG, Sandrin MS, Ierino FL. Differential cytokine expression and regulation of human anti-pig xenogeneic responses by modified porcine dendritic cells. Xenotransplantation 2009; 15:257-67. [PMID: 18957048 DOI: 10.1111/j.1399-3089.2008.00477.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND Porcine dendritic cells (DC) are likely to be pivotal cells in the initiation of stimulatory and potential tolerogenic responses to xenoantigens, however, there are limited studies characterizing these antigen presenting cells. METHODS Porcine PBMC (CD172a(+)) were cultured with GM-CSF and IL-4 and phenotype and functional capabilities assessed. Lipopolysaccharide (LPS), IL-10, and IL-3 were added to the GM-CSF/IL-4 DC cultures to determine phenotypic and functional changes. Quantitative real-time polymerase chain reaction (PCR) for key cytokines was performed and the modified porcine DC were further assessed by primary mixed lymphocyte reaction to determine the effect of LPS, IL-10, and IL-3 on stimulatory capability. RESULTS Porcine PBMC (CD172(+)) cultured with GM-CSF and IL-4 produced cells with DC morphology, which were major histocompatability complex (MHC) class II(+), CD14(-/lo), and CD1a(lo). Addition of IL-10 or IL-3 to GM-CSF/IL-4 DC cultures produced cells with lower levels of MHC class II and higher levels of antigen uptake consistent with less mature DC. Quantitative real-time PCR of DC showed the addition of IL-10 induced an increase in IL-10 mRNA, no detectable IL-12, and reduced IL-6 mRNA. The addition of IL-3 to DC cultures decreased IL-12, IL-6 and tumor necrosis factor (TNF), with no change in IL-10 mRNA. GM-CSF/IL-4 DC induced strong human lymphocyte proliferation, compared with significantly reduced stimulatory capacity induced by IL-10 and IL-3 treated DC cultures. CONCLUSIONS The profound effect on differential DC cytokine profile and reduced human anti-pig responses has important therapeutic implications in xenotransplantation. The mechanism of altered regulation warrants further investigation.
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Charniot JC, Bonnefont-Rousselot D, Albertini JP, Zerhouni K, Dever S, Richard I, Nataf P, Pavie A, Monsuez JJ, Delattre J, Artigou JY. Oxidative stress implication in a new ex-vivo cardiac concordant xenotransplantation model. Free Radic Res 2007; 41:911-8. [PMID: 17654048 DOI: 10.1080/10715760701429775] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Xenotransplantation (XT) reveals a growing interest for the treatment of cardiomyopathy. The major barrier is an acute vascular rejection due to an acute humoral rejection. This pathogenesis is a difficult issue and in order to elaborate means for its prevention, we analysed the implication of oxidative stress (OS) on hearts from mini-pigs followed by reperfusion with either autologous or human blood in an attempt to simulate xenotransplantation. About 14 hearts were studied after a Langendorff blood reperfusion: allografts with autologous blood (n = 7) or xenografts with human blood (n = 7). Blood samples were drawn from the coronary sinus to assess ischemia and OS. In xenografts, arrhythmias occurred more frequently (p < 0.01, left ventricular systolic pressure decreased more significantly (p < 0.05), thiobarbituric acid-reactive substances concentrations increased at 30 min (0.7 +/- 0.1 vs. 2.4 +/- 0.3 mmol/l; p < 0.05) while vitamin A levels decreased (p < 0.05). XT was associated with a significant increase in ischemic injury and OS production. OS might play an eminent role in hyperacute humoral rejection.
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15
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Manzi L, Montaño R, Abad MJ, Arsenak M, Romano E, Taylor P. Expression of human soluble complement receptor 1 by a pig endothelial cell line inhibits lysis by human serum. Xenotransplantation 2006; 13:75-9. [PMID: 16497215 DOI: 10.1111/j.1399-3089.2005.00265.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The importance of complement activation and naturally occurring anti-pig antibodies in the hyperacute rejection (HAR) observed in models of pig-to-human xenotransplantation is well established. To overcome this, much effort has been dedicated to preparing transgenic pigs by knocking out Galalpha(1-3)Gal expression in these animals, or knocking in the expression of human complement regulatory proteins (CRPs), such as CD59 or decay accelerating factor. A soluble form of another membrane CRP, complement receptor type 1 (CR1), has also been shown to inhibit complement activation. Here, we show that transfection of a pig endothelial cell line with a truncated form of human soluble complement receptor 1 (sCR1) almost completely protected these cells from complement-mediated lysis by human AB serum. Pigs genetically manipulated to express human sCR1 may represent an additional strategy to inhibit HAR of pig-to-human transplanted organs.
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Affiliation(s)
- Lorna Manzi
- Laboratory of Cellular and Molecular Pathology, Centre for Experimental Medicine, Venezuelan Institute for Scientific Research (IVIC), Caracus, Venezuela
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16
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Ramcharran S, Wang H, Hosiawa K, Kelvin D, Zhong R. Manipulation of cytokines as a novel approach to overcome xenotransplant rejection. Transplant Rev (Orlando) 2005. [DOI: 10.1016/j.trre.2005.12.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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17
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Hayashi S, Leu D, Yamii Y, Mei G, Takagi H, Nakao A. Effect of Adenovirus-Mediated Transfer of the CTLA4IG Gene in Hamster-to-Rat Xenotransplantation. Transplantation 2005; 80:494-9. [PMID: 16123724 DOI: 10.1097/01.tp.0000168151.83816.f4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Costimulatory molecules such as CD28 and B7 are essential for T cell activation, as well as playing a role in the T cell receptor and major histocompatibility complex pathway. It is well known that rejection in allotransplantation is diminished by treatment with CTLA4Ig, but whether a similar effect occurs in xenotransplantation remains to be determined. METHODS In this study, we investigated whether adenovirus-mediated gene transfer with CTLA4Ig cDNA by intravenous injection to the recipient is effective in suppression in hamster-to-rat cardiac xenotransplantation. RESULTS With CTLA4Ig gene transfer, the duration of gene expression was clearly prolonged, based on reduced production of antiadenovirus antibody and shrinkage of the spleen. The survival of cardiac xenografts was significantly prolonged with CTLA4Ig gene transfer compared to the control graft, and survival with combination use of FK506 and CTLA4Ig gene transfer in xenotransplantation was also significantly prolonged compared to that with CTLA4Ig gene transfer alone. Cessation of the cardiac graft in the combination treatment occurred in parallel with the elevation of antihamster IgM antibodies in rat sera. CONCLUSIONS These results suggest that adenovirus-mediated CTLA4Ig gene transfer is effective for immunosuppression in hamster-to-rat xenotransplantation.
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Affiliation(s)
- Shuji Hayashi
- Department of Surgery II, Nagoya University School of Medicine, and JRtokai Hospital, Nagoya, Japan.
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18
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Abstract
The complement system provides natural immunity against microbes and is an effector arm of antibody-mediated humoral immunity. It promotes the inflammatory process by activating cells and facilitates microbial destruction through opsonisation and lysis. Given this tissue damaging potential, it is not surprising that nearly half of the proteins of the complement system are regulators. The complement system can mediate undesirable cellular damage in autoantibody-mediated conditions, for example myasthenia gravis, immune-complex excess syndromes, such as systemic lupus erythaematosus, ischaemia-reperfusion states, hyperacute rejection of transplants, organ failure conditions (e.g., adult respiratory distress syndrome [ARDS]), Alzheimer's disease (AD) and related neurodegenerative disorders. A complement inhibitor has been lacking in the therapeutic arsenal. However, there are now several such agents being assessed in clinical trials and others under development. Current approaches include soluble versions of membrane regulatory proteins, humanised antibodies to components, small molecule inhibitors at various stages of the pathway and transgenic animals expressing human complement regulators for xenotransplantation. These and other strategies should lead to an effective means with which to inhibit complement activation in clinical medicine.
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Affiliation(s)
- M K Liszewski
- Department of Medicine, Washington University School of Medicine, 660 South Euclid, Box 8045, St Louis, MO 63110, USA
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19
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Alisky JM. Xenografts are an achievable breakthrough. Med Hypotheses 2004; 63:92-7. [PMID: 15193356 DOI: 10.1016/j.mehy.2004.01.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2003] [Accepted: 01/12/2004] [Indexed: 10/26/2022]
Abstract
The objective of this communication is to show that pig-to-human organ transplantation could be feasible through genetic engineering. By introducing into donor pigs several different tolerance promoting genetic modifications there can be a synergistic effect to produce extended tolerance for xenografted organs in human recipients. Nuclear-transfer cloning allows production of pigs with knockout mutations in the galactose-alpha-1,3-galactosyl transferase gene, in principle eliminating hyperacute rejection. Once hyperacute rejection is circumvented, long-term tolerance of xenografted organs should be possible through a combination of transgenic immunomodulating molecule, bone marrow chimerism and short to intermediate term use of immunosuppressive drugs. If immunomodulating transgenes are deleterious during pig development, inducible cre-recombinase excision of stop codons provides a means to delay expression of such transgenes until after transplantation. Zoonotic diseases can be circumvented via pathogen-free colonies and additional knockout mutations to disable porcine endogenous retrovirus and prion disease. Thus, there is now a technical and theoretical framework for serious efforts at cross-species transplantation.
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Affiliation(s)
- Joseph Martin Alisky
- Marshfield Clinic Research Foundation, 1000 Oak Avenue, Marshfield, WI 54449, USA.
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20
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McKenzie IFC, Li YQ, Xing PX, Dinatale I, Koulmanda M, Loveland BE, Sandrin MS. CD46 protects pig islets from antibody but not cell-mediated destruction in the mouse. Xenotransplantation 2003; 10:615-21. [PMID: 14708531 DOI: 10.1034/j.1399-3089.2003.00066.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We have previously reported that islets present in cultured fetal pig pancreas (FPP) are resistant to destruction by Galalpha(1,3)Gal antibodies and compliment, but are susceptible to the 'secondary' antibody response which occurs on transplanting pig islet tissue to Galo/o murine recipients. In a model of antibody-mediated graft rejection, we tested the resistance of porcine islets to antibody. Using FPP from human CD46 transgenic pigs, we now report that the complement regulator, CD46, affords protection from antibody-mediated rejection when mouse anti-pig serum (MAPS) was administered to scid mice bearing PFF grafts from either CD46 transgenic or normal pigs. Indeed, whereas normal pig islets were destroyed by an intraperitoneal (i.p.) injection of 0.1 to 0.2 ml of MAPS antibody, destruction of CD46-expressing transgenic islets required 0.5 ml, i.e. up to five times the amount. In contrast, there was no prolongation of the survival of CD46 transgenic mouse skin or heart major histocompatibility complex-compatible or -incompatible allografts--rejected by predominantly cellular immune mechanisms, as opposed to xenograft rejection. Although complement regulators have been examined for their protective role in hyperacute rejection of vascularized xenografts, it is clear that they also have protective effects in the later, antibody-mediated responses, but are unlikely to effect the inflammatory response in cell-mediated rejection.
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21
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Luo Y, Levy G, Garcia BM, Yang H, Phillips J, Noble L, Chakrabarti S, Grant D, Zhong R. Ex vivo and extracorporeal perfusion with hDAF pig kidneys. Xenotransplantation 2003; 10:410-21. [PMID: 12950984 DOI: 10.1034/j.1399-3089.2003.02050.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The present study was undertaken to determine whether human decay accelerating factor (hDAF) transgene would prevent hyperacute rejection (HAR) while perfused with human blood or extracorporeally in baboons. Four hDAF pig kidneys and three non-hDAF pig kidneys were perfused ex vivo with fresh human blood for 6 h. Additionally four hDAF pig kidneys and four non-hDAF pig kidneys were extracorporeally perfused in baboons and pigs, respectively, for 3 h. In ex vivo perfusion, the color of hDAF pig kidneys remained pink at the end of 6-h perfusion and they had normal histology, while non-hDAF kidneys developed HAR. HDAF pig kidneys had superior function over non-transgenic pig kidneys. Urine output was 17.31 +/- 3.70 ml/h for hDAF pig kidneys, and only 5.81 +/- 0.26 ml/h for non-hDAF kidneys (P < 0.05). Creatinine clearance was 1.16 +/- 1.24 ml/min for hDAF kidneys and 0.22 +/- 0.15 ml/min for non-hDAF kidneys (P < 0.05). Other functional data including potassium, urine specific density, and osmolality were normal in the hDAF kidneys, while in non-hDAF kidneys, serum potassium was elevated to over 9 mmol/l by the end of perfusion (P < 0.01). Non-hDAF kidneys also lost more sodium through urine than hDAF kidneys (173.67 +/- 14.05 mmol/l vs. 109 +/- 31 mmol/l, P < 0.05). In the extracorporeal perfusion, all the baboons tolerated the procedure well with normal hemodynamic and hemotologic profiles. These baboons were well until killed 42 to 56 days after perfusion, although their antiporcine antibodies were greatly elevated. We conclude that hDAF transgene protects against HAR, allowing the pig kidney to function normally while perfused with human blood, and that extracorporeal perfusion using hDAF pig kidneys is a safe procedure in baboons.
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Affiliation(s)
- Yigang Luo
- Department of Surgery, The University of Western Ontario, London, Ontario, Canada
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22
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Abstract
Xenotransplantation, in particular transplantation of pig cells, tissues and organs into human patients, may alleviate the current shortage of suitable allografts available for human transplantation. This overview addresses the physiological, immunological and virological factors considered with regard to xenotransplantation. Among the issues reviewed are the merits of using pigs as xenograft source species, the compatibility of pig and human organ physiology and the immunological hindrances with regard to the various types of rejection and attempts at abrogating rejection. Advances in the prevention of pig organ rejection by creating genetically modified pigs that are more suited to the human microenvironment are also discussed. Finally, with regard to virology, possible zoonotic infections emanating from pigs are reviewed, with special emphasis on the pig endogenous retrovirus (PERV). An in depth account of PERV studies, comprising their discovery as well as recent knowledge of the virus, is given. To date, all retrospective studies on patients with pig xenografts have shown no evidence of PERV transmission, however, many factors make us interpret these results with caution. Although the lack of PERV infection in xenograft recipients up to now is encouraging, more basic research and controlled animal studies that mimic the pig to human xenotransplantation setting more closely are required for safety assessment.
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Affiliation(s)
- Saema Magre
- Wohl Virion Centre, The Windeyer Institute of Medical Sciences, University College London, 46 Cleveland Street, London W1T 4JF, UK
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23
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Grubbs BC, Benson BA, Dalmasso AP. Characteristics of CD59 up-regulation induced in porcine endothelial cells by alphaGal ligation and its association with protection from complement. Xenotransplantation 2003; 10:387-97. [PMID: 12950982 DOI: 10.1034/j.1399-3089.2003.02088.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Activation of endothelial cells may result in proinflammatory and procoagulant changes, or in changes that protect the endothelial cells (EC) from injurious insults. Stimulation of porcine EC with human anti-porcine antibodies, or lectins from Bandeiraea simplicifolia that bind terminal Galalpha(1-3)Gal (abbreviated alphaGal), can induce EC protection from cytotoxicity by human complement. These EC also exhibit up-regulation of CD59 protein and mRNA expression. Porcine CD59 has been reported to protect porcine cells from human complement. Therefore we investigated the specificity requirements and other characteristics of the induced CD59 up-regulation, as well as the role of up-regulated CD59 in lectin-induced protection of EC from human complement. METHODS Aortic EC were incubated in vitro with alphaGal-binding lectins B. simplicifolia lectin I isolectin B4 (IB4) and B. simplicifolia lectin I (BS-I) and CD59 expression was assessed by flow cytometry and enzyme linked immunosorbent assay (ELISA). Binding requirement was studied using disaccharides containing either alphagalactosyl or betagalactosyl moieties to inhibit CD59 up-regulation. Protection from complement killing was assessed after incubation of EC with human serum as a source of anti-porcine antibodies and complement. The role of CD59 in lectin-induced protection was studied in the presence of an anti-pig CD59 antibody and after removal of CD59 using phosphatidylinositol (PI)-specific phospholipase C (PI-PLC). RESULTS We found that induction of CD59 up-regulation required specific binding of the lectin to terminal alphaGal and was not induced either by soluble factors that may be released from EC by stimulation with the lectin or by TNF-alpha, IFN-gamma, or IL-1alpha. Unstimulated or BS-I-treated EC showed little or no expression of decay accelerator factor (DAF). Removal of membrane-associated CD59 (and other proteins that are associated with the membrane through PI linkage) with PI-PLC from EC that had been exposed to lectin restored their complement sensitivity to various degrees, depending on the extent of lectin-induced protection. Cytotoxicity was completely restored in cells that exhibited partial protection induced with lectin at low doses or for a short period of time. However, EC that were fully resistant to complement did not regain sensitivity to complement after removal of CD59. Changes in CD59 expression did not modify the degree of C9 binding. CONCLUSIONS Induction of CD59 expression required specific binding of the lectin to terminal alphaGal and was not induced by soluble factors that may be released from EC by lectin stimulation. Increased CD59 expression may contribute to this form of protection from complement; however, mechanisms other than CD59 up-regulation appear to be essential for the development of full protection.
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Affiliation(s)
- Brian C Grubbs
- Department of Surgery, School of Medicine, University of Minnesota, Minneapolis, MN 55455, USA
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24
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Gonzalez-Stawinski GV, Daggett CW, Lau CL, Karoor S, Love SD, Logan JS, Gaca JG, Parker W, Davis RD. Non-anti-Gal alpha1-3Gal antibody mechanisms are sufficient to cause hyperacute lung dysfunction in pulmonary xenotransplantation. J Am Coll Surg 2002; 194:765-73. [PMID: 12081067 DOI: 10.1016/s1072-7515(02)01162-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND Hyperacute lung dysfunction, which is always associated with pulmonary pig-to-primate xenotransplantation is not well understood. The mechanisms associated with its occurrence seem to differ from mechanisms involved in hyperacute xenograft rejection seen in porcine hearts or kidneys transplanted into primates. To determine the contribution of anti-Gal alpha1-3Gal antibodies (alphaGAb) in such a process, we performed a set of orthotopic pig lung transplants into baboons depleted of alphaGAb and compared graft function and survival with those receiving only immunosuppression. STUDY DESIGN Pigs expressing human membrane cofactor protein served as donors. All baboons received triple immunosuppressive therapy. Depletion of alphaGAb in the experimental group (n = 4) was done by way of immunoadsorption using immunoaffinity membranes. Controls (n = 4) did not undergo immunoadsorption. Orthotopic lung transplants were performed through a left thoracotomy. Main pulmonary artery blood flow and pressure, left pulmonary artery blood flow, and left atrial pressure were recorded. RESULTS At 1 hour after reperfusion, pulmonary artery graft flows and pulmonary vascular resistances (PVR) were better in animals depleted of alphaGAb than in controls (605 +/- 325.2 mL/min versus 230 +/- 21 mL/min; 27.1 +/- 41.3 mmHg/L/min versus 63 +/- 1 mmHg/L/min). But at 3 hours after reperfusion average graft flows in baboons depleted of alphaGAb had decreased to 277.6 +/- 302.2 mL/min and PVRs had increased 58.3 +/- 42.0 mmHg/L/min. On the other hand, controls maintained stable flows and PVRs (223 +/- 23 mL/min; 61 +/- 3 mmHg/L/min). Survival was ultimately better in control baboons when compared with alphaGAb depleted ones (12.2 +/- 3.3 h versus 4.4 +/- 3.2 h). CONCLUSION Unlike heart and kidney xenograft transplants, hyperacute lung xenograft dysfunction seems to be mediated by factors other than alphaGAb.
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25
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Costa C, Barber DF, Fodor WL. Human NK cell-mediated cytotoxicity triggered by CD86 and Gal alpha 1,3-Gal is inhibited in genetically modified porcine cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 168:3808-16. [PMID: 11937533 DOI: 10.4049/jimmunol.168.8.3808] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Delayed xenograft rejection is a major hurdle that needs to be addressed to prolong graft survival in pig-to-primate xenotransplantation. NK cell activation has been implicated in delayed xenograft rejection. Both Ab-dependent and independent mechanisms are responsible for the high susceptibility of porcine cells to human NK cell-mediated cytotoxicity. Previous reports demonstrated a role of Galalpha1,3-Gal Ag in triggering the Ab-independent responses. We hypothesize that expression of CD80 and/or CD86 on porcine cells may also play a role in NK cell activation as human NK cells express a variant of CD28. Our initial analysis showed that porcine endothelial cells and fibroblasts express CD86, but not CD80. Genetic engineering of these cells to express hCD152-hCD59, a chimeric molecule designed to block CD86 in cis, was accompanied by a reduction in susceptibility to human NK cell-mediated cytotoxicity. The use of a specific anti-porcine CD86-blocking Ab and the NK92 and YTS cell lines further confirmed the involvement of CD86 in triggering NK cell-mediated lysis of porcine cells. Maximal protection was achieved when hCD152-hCD59 was expressed in H transferase-transgenic cells, which show reduced Galalpha1,3-Gal expression. In this work, we describe two mechanisms of human NK cell-mediated rejection of porcine cells and demonstrate that genetically modified cells resist Ab-independent NK cell-mediated cytotoxicity.
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MESH Headings
- Abatacept
- Animals
- Animals, Genetically Modified/immunology
- Antigens, CD/biosynthesis
- Antigens, CD/physiology
- Antigens, Differentiation/biosynthesis
- Antigens, Differentiation/genetics
- Antigens, Differentiation/pharmacology
- B7-1 Antigen/biosynthesis
- B7-2 Antigen
- CD28 Antigens/biosynthesis
- CD59 Antigens/biosynthesis
- CD59 Antigens/genetics
- CD59 Antigens/pharmacology
- CTLA-4 Antigen
- Cell Line
- Cell Membrane/immunology
- Cell Membrane/metabolism
- Cells, Cultured
- Cytotoxicity Tests, Immunologic
- Cytotoxicity, Immunologic/genetics
- Cytotoxicity, Immunologic/immunology
- Disaccharides/metabolism
- Disaccharides/physiology
- Endothelium, Vascular/cytology
- Endothelium, Vascular/immunology
- Endothelium, Vascular/metabolism
- Fibroblasts/immunology
- Fibroblasts/metabolism
- Fucosyltransferases/biosynthesis
- Fucosyltransferases/genetics
- Humans
- Immunity, Cellular/genetics
- Immunoconjugates
- Killer Cells, Natural/immunology
- Membrane Glycoproteins/antagonists & inhibitors
- Membrane Glycoproteins/biosynthesis
- Membrane Glycoproteins/physiology
- Recombinant Fusion Proteins/biosynthesis
- Recombinant Fusion Proteins/pharmacology
- Swine
- Transduction, Genetic
- Galactoside 2-alpha-L-fucosyltransferase
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Affiliation(s)
- Cristina Costa
- Department of Molecular Sciences, Alexion Pharmaceuticals, Cheshire, CT 06410, USA
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26
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Costa C, Zhao L, Burton WV, Rosas C, Bondioli KR, Williams BL, Hoagland TA, Dalmasso AP, Fodor WL. Transgenic pigs designed to express human CD59 and H-transferase to avoid humoral xenograft rejection. Xenotransplantation 2002; 9:45-57. [PMID: 12005104 DOI: 10.1034/j.1399-3089.2002.0o142.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Research in pig-to-primate xenotransplantation aims to solve the increasing shortage of organs for human allotransplantation and develop new cell- and tissue-based therapies. Progress towards its clinical application has been hampered by the presence of xenoreactive natural antibodies that bind to the foreign cell surface and activate complement, causing humoral graft rejection. Genetic engineering of donor cells and animals to express human complement inhibitors such as hCD59 significantly prolonged graft survival. Strategies to decrease the deposition of natural antibodies were also developed. Expression of human alpha1,2-fucosyltransferase (H transferase, HT) in pigs modifies the cell-surface carbohydrate phenotype resulting in reduced Galalpha1,3-Gal expression and decreased antibody binding. We have developed transgenic pigs that coexpress hCD59 and HT in various cells and tissues to address both natural antibody binding and complement activation. Functional studies with peripheral blood mononuclear cells and aortic endothelial cells isolated from the double transgenic pigs showed that coexpression of hCD59 and HT markedly increased their resistance to human serum-mediated lysis. This resistance was greater than with cells transgenic for either hCD59 or HT alone. Moreover, transgene expression was enhanced and protection maintained in pig endothelial cells that were exposed for 24 h to pro-inflammatory cytokines. These studies suggest that engineering donor pigs to express multiple molecules that address different humoral components of xenograft rejection represents an important step toward enhancing xenograft survival and improving the prospect of clinical xenotransplantation.
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Affiliation(s)
- Cristina Costa
- Department of Molecular Sciences, Alexion Pharmaceuticals, Inc, Cheshire, CT 06410, USA
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27
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Charlesworth JA, Peake PW, Pussell BA, Erlich JH. Complement in renal disease. Nephrology (Carlton) 2001. [DOI: 10.1046/j.1440-1797.2001.00057.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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28
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Carrington CA, dos Santos Cruz G. Effect of cell surface concentration of human DAF on transgenic pig aortic endothelial cells on the degree of protection afforded against human complement deposition. Xenotransplantation 2001; 8:100-5. [PMID: 11328580 DOI: 10.1034/j.1399-3089.2001.00086.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Cultures of hDAF transgenic porcine aortic endothelial cells (TPAEs) with levels of cell surface hDAF expression between 2000 and 300 000 molecules per cell have been used to determine the relationship between expression of hDAF and protection from human complement deposition in an in vitro model. At concentrations below 45 000 molecules per cell, the relationship between hDAF expression and degree of protection conferred is linear. Concentrations of 123 000 molecules per cell and higher give maximal protection (60% reduction of susceptibility to neat human serum) in this model. It is concluded that increasing hDAF expression above that displayed by the A74 line of hDAF transgenic pigs (240 000 +/- 15 000 molecules per cell) would not confer any additional benefit.
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Affiliation(s)
- C A Carrington
- Imutran Ltd (A Novartis Pharma AG Co.), PO Box 399, Cambridge CB2 2YP, UK
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29
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Abstract
This review summarizes the clinical history and rationale for xenotransplantation; recent progress in understanding the physiologic, immunologic, and infectious obstacles to the procedure's success; and some of the strategies being pursued to overcome these obstacles. The problems of xenotransplantation are complex, and a combination of approaches is required. The earliest and most striking immunologic obstacle, that of hyperacute rejection, appears to be the closest to being solved. This phenomenon depends on the binding of natural antibody to the vascular endothelium, fixation of complement by that antibody, and finally, activation of the endothelium and initiation of coagulation. Therefore, these three pathways have been targeted as sites for intervention in the process. The mechanisms responsible for the next immunologic barrier, that of delayed xenograft/acute vascular rejection, remain to be fully elucidated. They probably also involve multiple pathways, including antibody and/or immune cell binding and endothelial cell activation. The final immunologic barrier, that of the cellular immune response, involves mechanisms that are similar to those involved in allograft rejection. However, the strength of the cellular immune response to xenografts is so great that it is unlikely to be controlled by the types of nonspecific immunosuppression used routinely to prevent allograft rejection. For this reason, it may be essential to induce specific immunologic unresponsiveness to at least some of the most antigenic xenogeneic molecules.
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Affiliation(s)
- H Auchincloss
- Transplant Unit, Massachusetts General Hospital, Boston 02114, USA
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30
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Fiorante P, Banz Y, Mohacsi PJ, Kappeler A, Wuillemin WA, Macchiarini P, Roos A, Daha MR, Schaffner T, Haeberli A, Mazmanian GM, Rieben R. Low molecular weight dextran sulfate prevents complement activation and delays hyperacute rejection in pig-to-human xenotransplantation models. Xenotransplantation 2001; 8:24-35. [PMID: 11208188 DOI: 10.1046/j.0908-665x.2000.00088.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Dextran sulfate of 5000 molecular weight (DXS 5000) is known to block complement activation as well as the intrinsic coagulation cascade by potentiation of C inhibitor. The effect of DXS 5000 on hyperacute rejection (HAR) was tested in pig-to-human xenotransplantation models. For in vitro testing, a cytotoxicity assay was used with the pig kidney cell line PK15 as target cells and fresh, undiluted human serum as antibody and complement source. Ex vivo pig lung perfusion was chosen to assess DXS 5000 in a physiologic model. Pig lungs were perfused with fresh, citrate-anticoagulated whole human blood to which 1 or 2 mg/ml DXS 5000 were added; the lungs were ventilated and the blood de-oxygenated. Pulmonary vascular resistance (PVR) and blood oxygenation (deltapO2) were monitored throughout the experiment. Autologous pig blood and human blood without DXS 5000 served as controls. In the PK 15 assay DXS 5000 led to a complete, dose-dependent inhibition of human serum cytotoxicity with an average IC50 of 43 +/- 18 microg/ml (n=8). Pig lungs perfused with untreated human blood (n=2) underwent HAR within 105 +/- 64 min, characterized by increased PVR, decrease of deltapO2, and generalized edema. Microscopically, capillary bleeding as well as deposition of human antibodies, complement and fibrin could be observed. Addition of DXS 5000 (n=4) prolonged lung survival to 170 +/- 14 min for 1 mg/ml and 250 +/- 42 min for 2 mg/ml. and PVR values as well as edema formation were comparable to control lungs that were perfused with autologous pig blood (n=2). Activation of complement (activation products in serum, deposition on lung tissue) and the coagulation system (fibrin monomers) were significantly diminished as compared to human blood without DXS 5000. Binding of anti-Gal antibodies was not influenced, and in vitro experiments showed no evidence of complement depletion by DXS 5000. In conclusion, DXS 5000 is an efficient complement inhibitor in pig-to-human xenotransplantation models and therefore a candidate for complement-inhibitory/anti-inflammatory therapy either alone or in combination with other substances and warrants further investigation.
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Affiliation(s)
- P Fiorante
- Heart Transplantation Laboratory, Cardiology, Swiss Cardiovascular Center, University Hospital, Switzerland
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31
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Nagahama M, Shiraishi M, Oshiro T, Muto Y. Adenovirus-mediated triple gene transfer of human complement regulating proteins to the porcine endothelial cell. Transplant Proc 2000; 32:2511-3. [PMID: 11120272 DOI: 10.1016/s0041-1345(00)01790-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- M Nagahama
- First Department of Surgery, University of the Ryukyus, School of Medicine, Okinawa, Japan
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32
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Magnusson S, Strokan V, Mölne J, Nilsson K, Rydberg L, Breimer ME. Blocking of human anti-pig xenoantibodies by soluble GALα1-3GAL and Galα1-2GAL disaccharides; studies in a pig kidney in vitro perfusion model. Transpl Int 2000. [DOI: 10.1111/j.1432-2277.2000.tb01018.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Zhan Y, Martin RM, Sutherland RM, Brady JL, Lew AM. Local production of anti-CD4 antibody by transgenic allogeneic grafts affords partial protection. Transplantation 2000; 70:947-54. [PMID: 11014648 DOI: 10.1097/00007890-200009270-00012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Immunosuppressive drugs and anti-lymphocyte antibody are used clinically to suppress cellular rejection responses. However, these systemic regimens often led to general immunodeficiency and thus increased susceptibility to opportunistic infection and neoplasia. Immunosuppressive molecules delivered locally may be a way of inhibiting rejection responses, whereas systemic immunity is preserved. To achieve protective local immunosuppression, we produced a graft secreting its own immunomodulator, by deriving transgenic mice expressing a chimeric anti-CD4 antibody (GK2c) in the pancreas. METHODS AND RESULTS Transgenic mice in bml genetic background expressing a modified anti-mouse CD4 antibody (GK2c) under two promoters have been produced. Tissue expression of GK2c was detected by immunoperoxidase staining. Under the cytomegalovirus promoter, there was abundant GK2c expression in pancreatic exocrine tissue. Under the rat preproinsulin II promoter, there was abundant GK2c expression in pancreatic endocrine tissue only. High-expression transgenic lines had 10-100 microg/ml GK2c in blood plasma. By flow cytometry, these transgenic mice were devoid of CD4+ cells in their peripheral lymphoid organs. To test transgenic mice as donors, fetal pancreata from transgenic mice were grafted into fully allogeneic CBA mice under the kidney capsule, transgenic grafts had prolonged survival compared with control non-transgenic grafts. Furthermore, GK2c transgenic grafts had reduced infiltration with an absence of CD4+ cells at the graft site without any effect on the cell composition in lymphatic tissues. CONCLUSION Transgenic grafts that secrete anti-CD4 antibody can afford some protection against graft rejection, while only affecting the CD4 population at the graft site.
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Affiliation(s)
- Y Zhan
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
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Imai M, Takigami K, Guckelberger O, Kaczmarek E, Csizmadia E, Bach FH, Robson SC. Recombinant adenoviral mediated CD39 gene transfer prolongs cardiac xenograft survival. Transplantation 2000; 70:864-70. [PMID: 11014639 DOI: 10.1097/00007890-200009270-00003] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Extracellular ATP and ADP may be important mediators of vascular inflammation and thrombosis. Nucleoside triphosphate diphosphohydrolase (NTPDase or CD39) is a vascular ectoenzyme that hydrolyses ATP and ADP; however, this activity is lost during reperfusion injury. We show that the supplementation of NTPDase activity within xenograft vasculature using CD39 recombinant adenoviruses (AdCD39) has protective effects in vivo. METHODS Recombinant adenoviruses containing human CD39 or beta-galactosidase (Adbeta-gal) encoding genes were constructed. Hartley guinea pig coronary arteries were perfused ex vivo with University of Wisconsin solution containing 10(9) plaque-forming units of the recombinant adenovirus. Infected grafts were then implanted in the abdomen of complement depleted Lewis rats. RESULTS NTPDase activities decreased in all grafts within the first 24 hr and subsequently recovered only in those hearts infected with AdCD39. Immunohistological examination of AdCD39-infected grafts confirmed successful CD39 gene transfer into the endocardium and macrovasculature. Expression of CD39 modestly prolonged graft survival (90.2+/-5.4 hr, mean+/-SD, n=5) when compared with Adbeta-gal-infected grafts (67.4+/-5.4 hr, P<0.005) and perfusion controls (66.4+/-5.2 hr; P<0.005). CONCLUSIONS Recombinant adenoviral infection can induce expression of CD39 within cardiac xenografts and provide survival benefits in vivo. Our data show that ex vivo infection by recombinant adenovirus vectors can result in vascular expression of a potential therapeutic agent.
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Affiliation(s)
- M Imai
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
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35
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van den Berg CW, Rix C, Hanna SM, Perez de la Lastra JM, Morgan BP. Role and regulation of pig CD59 and membrane cofactor protein/CD46 expressed on pig aortic endothelial cells. Transplantation 2000; 70:667-73. [PMID: 10972227 DOI: 10.1097/00007890-200008270-00022] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Hyperacute rejection in xenotransplantation is caused by activation of complement (C) on endothelium. We have previously shown that purified C-regulators of the pig (CD59 and membrane cofactor protein [MCP]) are efficient regulators of human C (HuC). The aim of this study was to clarify the role of endogenously expressed C-regulatory molecules on pig endothelium in the protection against hyperacute rejection. METHODS Porcine aortic endothelial cells (PAEC) were harvested and cultured for various passages. PAEC were examined for the expression of endogenous pig CD59 and MCP by flow cytometry. PAEC were assessed for their susceptibility to lysis by HuC. The effect of phorbol 12-myristate 13-acetate and various cytokines on the expression of MCP and CD59 and C-susceptibility was assessed. RESULTS Primary PAEC showed an initial high level of expression of pig CD59, however, upon culturing, CD59 levels decreased dramatically to about 20% after five passages. In contrast, levels of MCP doubled upon culturing of PAEC to confluency and remained stable during at least five passages. Primary cells and cells in the early passages were more resistant to HuC than cells that were cultured for longer. Blocking the function of CD59 but not of MCP using monoclonal antibody increased the susceptibility to HuC. Purified human CD59 incorporated to a level of expression similar to that of pig CD59 reversed the increased C-susceptibility, suggesting that pig and human CD59 are similarly protective against HuC. Increase of C-resistance and of expression of pig MCP, but not of CD59, was achieved upon incubation with phorbol 12-myristate 13-acetate. Tumor necrosis factor-alpha, interleukin-1beta, interleukin-4, or interferon-gamma had no effect on C-regulator expression or C-susceptibility. CONCLUSIONS These data demonstrate the importance of using primary PAEC or cells in the first passages of culturing in in vitro models of xenotransplantation and show that pig MCP and, in particular, pig CD59 play an important role in protection of PAEC from HuC.
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Affiliation(s)
- C W van den Berg
- Department of Pharmacology, Therapeutics and Toxicology, UWCM, Cardiff, United Kingdom.
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36
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Tu CF, Hsieh SL, Lee JM, Yang LL, Sato T, Lee KH, Weng CN, Mao SJ, Tsuji K, Lee CJ. Successful generation of transgenic pigs for human decay-accelerating factor and human leucocyte antigen DQ. Transplant Proc 2000; 32:913-5. [PMID: 10936271 DOI: 10.1016/s0041-1345(00)01035-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- C F Tu
- Department of Applied Biology, Pig Research Institute, Taiwan
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Tector AJ, Fridell JA, Ruiz P, Khurana RJ, Jensen G, Mak A, Greinke D, Salazar J, Stevenson W, Metrakos P, Tchervenkov J. Experimental discordant hepatic xenotransplantation in the recipient with liver failure: implications for clinical bridging trials. J Am Coll Surg 2000; 191:54-64. [PMID: 10898184 DOI: 10.1016/s1072-7515(00)00293-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Clinical xenotransplantation might start with bridge-to-bridge trials. Situations where hyperacute rejection is avoided would provide opportunities for the initiation of bridging trials. Patients with liver failure have a diminished capacity to initiate antibody and complement-induced injury of xenogeneic endothelium. Hyperacute rejection of a liver xenograft manifests as a coagulopathy. We examined the ability of a recipient with liver failure to hyperacutely reject a liver xenograft in the dog-to-pig model in the immediate postoperative period. STUDY DESIGN Liver failure in pigs was induced with galactosamine. Canine livers were transplanted into pigs with liver failure and into healthy pigs. The postoperative course was monitored for 1 hour for histologic changes in the xenograft, changes in platelet counts, and whole blood clotting with Sonoclot analysis. In vitro assays with pig serum and canine hepatic sinusoidal endothelial cells were used to assess the effect of liver failure on serum cytotoxicity and xenoreactive antibody levels. RESULTS All untreated pig recipients of liver xenografts died from a coagulopathy. Recipients with liver failure manifested no signs of coagulopathy, and had minimal change in platelet counts or Sonoclot (Sienco Inc., Morrison, CO) tracings. Liver xenograft biopsies from recipients with liver failure showed no evidence of the tissue injury that characterized the biopsies of control recipients. Serum from pigs was less cytotoxic to the canine hepatic sinusoidal endothelium after induction of liver failure. The xenoreactive antibody levels and repertoire were similar in the pig serum before and after liver failure was induced. CH50 (total complement) levels were diminished in pigs after the induction of liver failure. CONCLUSIONS Liver xenotransplantation used in bridging trials in recipients with liver failure might not face the barrier of hyperacute rejection.
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Affiliation(s)
- A J Tector
- McGill University Department of Surgery, Royal Victoria Hospital, Montreal, PQ, Canada
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Cowan PJ, Aminian A, Barlow H, Brown AA, Chen CG, Fisicaro N, Francis DM, Goodman DJ, Han W, Kurek M, Nottle MB, Pearse MJ, Salvaris E, Shinkel TA, Stainsby GV, Stewart AB, d'Apice AJ. Renal xenografts from triple-transgenic pigs are not hyperacutely rejected but cause coagulopathy in non-immunosuppressed baboons. Transplantation 2000; 69:2504-15. [PMID: 10910270 DOI: 10.1097/00007890-200006270-00008] [Citation(s) in RCA: 171] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The genetic modification of pigs is a powerful strategy that may ultimately enable successful xenotransplantation of porcine organs into humans. METHODS Transgenic pigs were produced by microinjection of gene constructs for human complement regulatory proteins CD55 and CD59 and the enzyme alpha1,2-fucosyltransferase (H-transferase, HT), which reduces expression of the major xenoepitope galactose-alpha1,3-galactose (alphaGal). Kidneys from CD55/HT and CD55/CD59/HT transgenic pigs were transplanted into nephrectomised, nonimmunosuppressed adult baboons. RESULTS In several lines of transgenic pigs, CD55 and CD59 were expressed strongly in all tissues examined, whereas HT expression was relatively weak and did not significantly reduce alphaGal. Control nontransgenic kidneys (n=4) grafted into baboons were hyperacutely rejected within 1 hr. In contrast, kidneys from CD55/HT pigs (n=2) were rejected after 30 hr, although kidneys from CD55/CD59/HT pigs (n=6) maintained function for up to 5 days. In the latter grafts, infiltration by macrophages, T cells, and B cells was observed at days 3 and 5 posttransplantation. The recipients developed thrombocytopenia and abnormalities in coagulation, manifested in increased clotting times and an elevation in the plasma level of the fibrin degradation product D-dimer, within 2 days of transplantation. Treatment with low molecular weight heparin prevented profound thrombocytopenia but not the other aspects of coagulopathy. CONCLUSIONS Strong expression of CD55 and CD59 completely protected porcine kidneys from hyperacute rejection and allowed a detailed analysis of xenograft rejection in the absence of immunosuppression. Coagulopathy appears to be a common feature of pig-to-baboon renal transplantation and represents yet another major barrier to its clinical application.
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Affiliation(s)
- P J Cowan
- Immunology Research Centre, St Vincent's Hospital, Fitzroy, Victoria, Australia
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Kroshus TJ, Salerno CT, Yeh CG, Higgins PJ, Bolman RM, Dalmasso AP. A recombinant soluble chimeric complement inhibitor composed of human CD46 and CD55 reduces acute cardiac tissue injury in models of pig-to-human heart transplantation. Transplantation 2000; 69:2282-9. [PMID: 10868627 DOI: 10.1097/00007890-200006150-00011] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Inasmuch as complement plays a critical role in many pathological processes and in xenograft rejection, efficient complement inhibitors are of great interest. Because the membrane-associated complement inhibitors are very effective, recombinant soluble molecules have been generated. METHODS We tested the efficacy of complement activation blocker-2 (CAB-2), a recombinant soluble chimeric protein derived from human decay accelerating factor (DAF, CD55) and membrane cofactor protein (MCP, CD46), in two models of pig-to-human xenotransplantation in which tissue injury is complement mediated. The in vitro model consisted of porcine aortic endothelial cells and human serum, and the ex vivo model consisted of a porcine heart perfused with human blood. RESULTS In vitro, addition of CAB-2 to serum inhibited cytotoxicity and the deposition of C4b and iC3b on the endothelial cells. Ex vivo, addition of CAB-2 to human blood prolonged organ survival from 17.3 +/- 6.4 min in controls to 108 +/- 55.6 min with 910 nM (100 microg/ml) CAB-2 and 219.8 +/- 62.7 min with 1820 nM (200 microg/ml) CAB-2. CAB-2 also retarded the onset of increased coronary vascular resistance. The complement activity of the perfusate was reduced by CAB-2, as was the generation of C3a and SC5b-9. The myocardial tissues had similar deposition of IgG, IgM, and Clq; however, CAB-2 reduced the deposition of C3, C4, and C9. Hearts surviving >240 min demonstrated trace to no deposition of C9 and normal histologic architecture. CONCLUSION These results indicate that CAB-2 can function as an inhibitor of complement activation and markedly reduce tissue injury in models of pig-to-human xenotransplantation and thus may represent a useful therapeutic agent for xenotransplantation and other complement-mediated conditions.
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Affiliation(s)
- T J Kroshus
- Department of Surgery and Laboratory Medicine and Pathology, University of Minnesota, Minneapolis 55455, USA
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Mora M, Lazzer M, Marsicano G, Mulder LC, Carraresi L, Pieri A, Benanchi A, Grifoni D, Nuti S, Bruzzone P, Comporti M, Cortesini R, Rossini M. An in vivo model of hyperacute rejection: characterization and evaluation of the effect of transgenic human complement inhibitors. Transgenic Res 2000; 9:205-13. [PMID: 11032369 DOI: 10.1023/a:1008928713058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Hyperacute rejection (HAR) occurring after transplantation within phylogenetically distant species is a severe reaction triggered by preexisting xenoreactive antibodies and complement activation, leading to the destruction of the donor organ. Expression of human complement inhibitors in transgenic pig organs prolongs the survival of xenograft in experimental models. Moreover, the extent of protection from hyperacute rejection is dependent on the level and site of expression of the transgenic molecules and, probably, on the combination of different molecules. In this regard a small animal model to test the efficacy of expression vectors and different human molecules could be very advantageous. A murine model developed in our laboratory was characterized by measurement of several parameters characteristic of HAR in the livers of control and transgenic mice expressing transgenic human DAF (CD55) or MCP (CD46) at the end of 2 h of perfusion with human plasma and after I day. The parameters studied were heamatological values of hepatic functions (GOT and GPT), induction of pro-inflammatory molecules and histopathological evaluation. Cytokines (IL-1alpha, IL-1beta, IL-6) induction and exposure of P-selectin on the endothelial cell surface, was only observed in control animals after 2 h of perfusion, as an early event. GOT and GPT values increase dramatically after 2 h perfusion and 1 day after the treatment according to the histopathological observation of liver damage. On the contrary, the livers of hDAF or hMCP transgenic mice, under the same treatment were significantly protected although the extent of this protection is dependent on the level of expression of transgenic human molecules.
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Affiliation(s)
- M Mora
- Consorzio Interuniversitario per i Trapianti d'Orgazno Rome, Italy
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Kulick DM, Salerno CT, Dalmasso AP, Park SJ, Paz MG, Fodor WL, Bolman RM. Transgenic swine lungs expressing human CD59 are protected from injury in a pig-to-human model of xenotransplantation. J Thorac Cardiovasc Surg 2000; 119:690-9. [PMID: 10733757 DOI: 10.1016/s0022-5223(00)70003-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Pulmonary xenotransplantation is currently limited by hyperacute rejection mediated in part by xenoreactive natural antibody and complement. Transgenic swine organs that express the human complement regulatory protein CD59 have demonstrated improved survival in models of pig-to-primate xenotransplantation. OBJECTIVE The purpose of this study was to evaluate transgenic swine lungs that express the human complement regulatory protein CD59 in a model of pig-to-human xenotransplantation. METHODS Transgenic swine lungs (n = 5, experimental group) and outbred swine lungs (n = 6, control group) were perfused with fresh, whole human blood through a centrifugal pump on an ex vivo circuit. Functional data were collected throughout perfusion. Immunoglobulin and complement studies were performed on perfusate samples, and both histologic and immunofluorescent analyses were performed on tissue sections. RESULTS Mean lung survival for the experimental group was increased when compared with controls, 240 +/- 0 minutes versus 35.3 +/- 14.5 minutes, respectively, with a P value of less than.01. A decreased rise in pulmonary vascular resistance at 15 minutes was observed in the experimental group (343 +/- 87 mm Hg. L(-1). min(-1), in contrast to the control group (1579 +/- 722 mm Hg. L(-1). min(-1); P <.01). Pulmonary compliance at 15 minutes was improved for the experimental group versus control group (9.31 +/- 1.41 mL. cm(-2) H(2)O and 4.11 +/- 2.84 mL. cm(-2) H(2)O, respectively; P <.01). SC5b-9 generation in the plasma perfusate was delayed for the experimental group versus the control group. Immunofluorescent examination of tissue sections demonstrated equivalent deposition of immunoglobulin G, immunoglobulin M, C1q, and C3 in both groups, with reduced deposition of C9 in the experimental group. CONCLUSIONS Transgenic swine pulmonary xenografts that express the human complement regulatory protein CD59 demonstrated improved function and survival in an ex vivo model of pig-to-human xenotransplantation.
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Affiliation(s)
- D M Kulick
- Department of Surgery, University of Minnesota, Minneapolis 55455, USA.
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Abstract
BACKGROUND The success of clinical transplantation has led to a large discrepancy between donor organ availability and demand; considerable pressure exists to develop an alternative source of organs. The use of animal organs for donation is a possible solution that is not yet clinically applicable. METHODS AND RESULTS A literature review was performed based on a Medline search to find articles on xenotransplantation. Keywords included hyperacute, acute vascular, xenograft rejection combined with concordant and discordant. Additional references cited in these articles from journals not included in Medline were obtained from the British Library. Limited information on unpublished, preliminary work has been included from sources known to the authors, based on their research work in the field. One hundred and forty-six references and four personal communications have been included in this review article. CONCLUSION A greater understanding of the pathogenesis of xenograft rejection is developing rapidly. Strategies to abrogate hyperacute rejection have proved successful, but control of antibody-driven acute vascular rejection has not yet been achieved. The safety and viability of xenotransplantation as a therapeutic modality are still unproven.
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Affiliation(s)
- B Soin
- Department of Surgery, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK
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Low WC, Duan WM, Keene CD, Ni HT, Westerman MA. Immunobiology of Neural Xenotransplantation. NEUROMETHODS 2000. [DOI: 10.1007/978-1-59259-690-4_23] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Abstract
While the technique of homologous recombination, or gene targeting, has led to the generation of transgenic mice of great value to biomedical research, similar approaches are only being developed in other species. With the exception of recent reports on the generation of gene-targeted sheep, the technology in domestic animals is still in its infancy (45). The development of techniques for generating large animals with deleted or modified genes will result in the generation of animals of great value to society. While the technical difficulties to achieve gene targeting in domestic species are significant, they are not insurmountable. Potential applications in both the bovine and porcine species are described with particular emphasis on the generation of cattle resistant to bovine spongiform encephalopathy (BSE) and pigs that can be of use in xenotransplantation.
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Affiliation(s)
- J A Piedrahita
- Department of Veterinary Anatomy and Public Health, Texas A&M University, College Station 77843, USA
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45
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Wang H, Rollins SA, Gao Z, Garcia B, Zhang Z, Xing J, Li L, Kellersmann R, Matis LA, Zhong R. Complement inhibition with an anti-C5 monoclonal antibody prevents hyperacute rejection in a xenograft heart transplantation model. Transplantation 1999; 68:1643-51. [PMID: 10609940 DOI: 10.1097/00007890-199912150-00007] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND The present study was undertaken to determine whether anti-complement 5 (C5) monoclonal antibodies (mAb) prevent hyperacute rejection (HAR) in a rat-to-presensitized mouse heart transplantation model and whether these mAb, combined with cyclosporine (CsA) and cyclophosphamide (CyP), can achieve long-term graft survival. METHODS BALB/c mice were presensitized with 2x10(7) splenocytes from Lewis rats 14 days before grafting. Heart grafts from Lewis rats were heterotopically transplanted into BALB/c mice. Presensitized mice were treated with either anti-C5 mAb or a combination of anti-C5 mAb, CsA, and CyP. Controls included: presensitized mice with no treatment, presensitized mice treated with either CsA + CyP or IgG, and nonpresensitized mice with either no treatment or with CsA + CyP treatment. RESULTS Although typical features of HAR were evident in the presensitized grafts, the mAb completely inhibited complement activation and successfully prevented HAR. Despite complement inactivation, the graft was rejected on postoperative day 6 with acute vascular rejection (AVR) also known as delayed xenograft rejection (DXR). Notably, this type of rejection cannot be effectively overcome by CsA and CyP. CONCLUSIONS We conclude that (1) anti-C5 mAb prevents HAR, (2) AVR/DXR still occurs when HAR is prevented by complement inactivation, and (3) AVR/DXR cannot be overcome by conventional immunosuppression. These data suggest that anti-C5 mAb may be valuable for preventing HAR in future clinical xenotransplantation and that additional interventions may be required to address AVR/DXR.
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Affiliation(s)
- H Wang
- Department of Surgery, The University of Western Ontario, London, Canada
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46
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Costa C, Zhao L, Burton WV, Bondioli KR, Williams BL, Hoagland TA, Ditullio PA, Ebert KM, Fodor WL. Expression of the human alpha1,2-fucosyltransferase in transgenic pigs modifies the cell surface carbohydrate phenotype and confers resistance to human serum-mediated cytolysis. FASEB J 1999; 13:1762-73. [PMID: 10506579 DOI: 10.1096/fasebj.13.13.1762] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Hyperacute rejection (HAR) is the first critical immunological hurdle that must be addressed in order to develop xenogeneic organs for human transplantation. In the area of cell-based xenotransplant therapies, natural antibodies (XNA) and complement have also been considered barriers to successful engraftment. Transgenic expression of human complement inhibitors in donor cells and organs has significantly prolonged the survival of xenografts. However, expression of complement inhibitors without eliminating xenogeneic natural antibody (XNA) reactivity may provide insufficient protection for clinical application. An approach designed to prevent XNA reactivity during HAR is the expression of human alpha1, 2-fucosyltransferase (H-transferase, HT). H-transferase expression modifies the cell surface carbohydrate phenotype of the xenogeneic cell, resulting in the expression of the universal donor O antigen and a concomitant reduction in the expression of the antigenic Galalpha1,3-Gal epitope. We have engineered various transgenic pig lines that express HT in different cells and tissues, including the vascular endothelium. We demonstrate that in two different HT transgenic lines containing two different HT promoter constructs, expression can be differentially regulated in a constitutive and cytokine-inducible manner. The transgenic expression of HT results in a significant reduction in the expression of the Galalpha1,3-Gal epitope, reduced XNA reactivity, and an increased resistance to human serum-mediated cytolysis. Transgenic pigs that express H-transferase promise to become key components for the development of xenogeneic cells and organs for human transplantation.
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Affiliation(s)
- C Costa
- Department of Molecular Sciences, Alexion Pharmaceuticals Inc, New Haven, Connecticut 06511, USA
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Hampshire V, Davis J. Inside the mouse hospital: science, animal welfare and strife in the drive for AAALAC accreditation. Transgenic Res 1999; 8:251-2. [PMID: 10621972 DOI: 10.1023/a:1008994416860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Taboit-Dameron F, Malassagne B, Viglietta C, Puissant C, Leroux-Coyau M, Chéreau C, Attal J, Weill B, Houdebine LM. Association of the 5'HS4 sequence of the chicken beta-globin locus control region with human EF1 alpha gene promoter induces ubiquitous and high expression of human CD55 and CD59 cDNAs in transgenic rabbits. Transgenic Res 1999; 8:223-35. [PMID: 10478492 DOI: 10.1023/a:1008919925303] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Whatever its field of application, animal transgenesis aims at a high level of reproducible and stable transgene expression. In the case of xenotransplantation, prevention of hyperacute rejection of grafts of animal origin requires the use of organs expressing human inhibitors of complement activation such as CD55 (DAF) and CD59. Pigs transgenic for these molecules have been produced, but with low and variable levels of expression. In order to improve cDNA expression, a vector containing the 5'HS4 region from the LCR of the chicken beta-globin locus and the promoter and the first intron from the human EF1 alpha gene, was used to co-express human CD55 and CD59 cDNAs in transgenic rabbits. The transgenic lines with the 5'HS4 region displayed dramatically enhanced CD55 and CD59 mRNA concentrations in brain, heart, kidney, liver, lung, muscle, spleen and aortic endothelial cells in comparison with the transgenic lines without the 5'HS4 region. In the absence of the 5'HS4 region, only some of the transgenic lines displayed specific mRNAs and at low levels. Human CD55 and CD59 proteins were detectable in mononuclear cells from transgenic rabbits although at a lower level than in human mononuclear cells. On the other hand, primary aortic endothelial cells from a bi-transgenic line were very efficiently protected in vitro against human complement-dependent lysis. Transgenic rabbits harbouring the two human inhibitors of complement activation, CD55 and CD59, can therefore be used as new models in xenotransplantation. Moreover, the vector containing the 5'HS4 region from the LCR of the chicken beta-globin locus seems appropriate not only for xenotransplantation but also for any other studies involving transgenic animals in which cDNAs have to be expressed at a high level in all cell types.
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Affiliation(s)
- F Taboit-Dameron
- Laboratoire de Différenciation Cellulaire, Institut National de Recherche Agronomique, Jouy-en-Josas, France
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Costa C, Zhao L, Decesare S, Fodor WL. Comparative analysis of three genetic modifications designed to inhibit human serum-mediated cytolysis. Xenotransplantation 1999; 6:6-16. [PMID: 10355728 DOI: 10.1034/j.1399-3089.1999.00004.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Hyperacute rejection (HAR) remains a critical immunologic hurdle in the development of xenogeneic organs for human transplantation. Strategies that simultaneously eliminate both natural antibody reactivity and complement activation on the xenogeneic cell surface may be the best approach to achieve clinical application of xenogeneic vascularized organ transplantation. We have developed multiple lines of genetically manipulated mice to evaluate the combination of different genetic approaches aimed at inhibiting antibody and complement-mediated cell lysis. We utilized transgenic mice expressing the human complement inhibitor, CD59, the human 1,2-fucosyltransferase (H-transferase, HT) and the alpha1,3-galactosyltransferase (alpha1,3-GT) knock-out mouse line (Gal KO). Our data show that expression of hCD59 in combination with HT expression or the null phenotype of alpha1,3-GT are equally effective at preventing human serum-mediated cytolysis. Interestingly, the triple combination affords no additional protective effect. Therefore, coexpression of HT and a complement inhibitor is the most immediate strategy to genetically engineer transgenic pigs to be used as xenogeneic donors.
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Affiliation(s)
- C Costa
- Department of Molecular Sciences, Alexion Pharmaceuticals Inc., New Haven, CT 06511, USA
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Maher SE, Pflugh DL, Larsen NJ, Rothschild MF, Bothwell AL. Structure/function characterization of porcine CD59: expression, chromosomal mapping, complement-inhibition, and costimulatory activity. Transplantation 1998; 66:1094-100. [PMID: 9808497 DOI: 10.1097/00007890-199810270-00021] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Complement regulatory proteins have become important targets to potentially modulate inflammatory reactions or transplant rejection. Since pig into human xenotransplantation could potentially overcome the enormous shortage of donor organs and tissues, characterization of porcine complement regulatory proteins is critical. METHODS The porcine CD59 cDNA has been isolated from porcine aortic endothelial cells and its structure determined. In addition, a molecular genetic analysis of the gene and its transcriptional properties and a functional analysis have been performed utilizing the transfected cDNA. RESULTS The most prominent mRNA species is 1.8 kilobases but cloned reverse transcriptase polymerase chain reaction products suggest that multiple polyadenylation sites are utilized. Gene mapping was performed utilizing a polymorphism identified in the 3' UT, and the gene was localized to within 3 cM of follicle-stimulating hormone, beta polypeptide in the middle of the chromosome 2 linkage map. RNA expression was equivalent in endothelial, kidney, and testis cell lines. Comparisons have been made with CD59 sequences from other species to identify possible important domains of the protein. The cDNA has been utilized to express an epitope-tagged or wild-type protein either transiently on COS-7 cells or stably in Chinese hamster ovary cells. The porcine CD59 protein effectively inhibited the antibody-mediated lytic activity of both porcine and human complement. In contrast to human CD59, porcine CD59 is incapable of providing costimulation to human T cells. CONCLUSIONS These data suggest that overexpression of porcine CD59 might be more effective than human CD59 in prolonging xenograft survival with transgenic pig organs because of reduced immunoreactivity.
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Affiliation(s)
- S E Maher
- Section of Immunobiology, Yale University School of Medicine, New Haven, Connecticut 06520-8011, USA
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