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Mohiuddin MM, Corcoran PC, Singh AK, Azimzadeh A, Hoyt RF, Thomas ML, Eckhaus MA, Seavey C, Ayares D, Pierson RN, Horvath KA. B-cell depletion extends the survival of GTKO.hCD46Tg pig heart xenografts in baboons for up to 8 months. Am J Transplant 2012; 12:763-71. [PMID: 22070772 PMCID: PMC4182960 DOI: 10.1111/j.1600-6143.2011.03846.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Xenotransplantation of genetically modified pig organs offers great potential to address the shortage of human organs for allotransplantation. Rejection in Gal knockout (GTKO) pigs due to elicited non-Gal antibody response required further genetic modifications of donor pigs and better control of the B-cell response to xenoantigens. We report significant prolongation of heterotopic alpha Galactosyl transferase "knock-out" and human CD46 transgenic (GTKO.hCD46Tg) pig cardiac xenografts survival in specific pathogen free baboons. Peritransplant B-cell depletion using 4 weekly doses of anti-CD20 antibody in the context of an established ATG, anti-CD154 and MMF-based immunosuppressive regimen prolonged GTKO.hCD46Tg graft survival for up to 236 days (n = 9, median survival 71 days and mean survival 94 days). B-cell depletion persisted for over 2 months, and elicited anti-non-Gal antibody production remained suppressed for the duration of graft follow-up. This result identifies a critical role for B cells in the mechanisms of elicited anti-non-Gal antibody and delayed xenograft rejection. Model-related morbidity due to variety of causes was seen in these experiments, suggesting that further therapeutic interventions, including candidate genetic modifications of donor pigs, may be necessary to reduce late morbidity in this model to a clinically manageable level.
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Affiliation(s)
- MM Mohiuddin
- Cardiothoracic Surgery Research Program, NHLBI, NIH, Bethesda, MD
| | - PC Corcoran
- Cardiothoracic Surgery Research Program, NHLBI, NIH, Bethesda, MD
| | - AK Singh
- Cardiothoracic Surgery Research Program, NHLBI, NIH, Bethesda, MD
| | - A Azimzadeh
- University of Maryland Medical Center, Baltimore, MD
| | - RF Hoyt
- LAMS, NHLBI, NIH, Bethesda, MD
| | | | | | - C Seavey
- Cardiothoracic Surgery Research Program, NHLBI, NIH, Bethesda, MD
| | | | - RN Pierson
- University of Maryland Medical Center, Baltimore, MD
| | - KA Horvath
- Cardiothoracic Surgery Research Program, NHLBI, NIH, Bethesda, MD
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Ekser B, Klein E, He J, Stolz DB, Echeverri GJ, Long C, Lin CC, Ezzelarab M, Hara H, Veroux M, Ayares D, Cooper DKC, Gridelli B. Genetically-engineered pig-to-baboon liver xenotransplantation: histopathology of xenografts and native organs. PLoS One 2012; 7:e29720. [PMID: 22247784 PMCID: PMC3256162 DOI: 10.1371/journal.pone.0029720] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 12/02/2011] [Indexed: 11/18/2022] Open
Abstract
Orthotopic liver transplantation was carried out in baboons using wild-type (WT, n = 1) or genetically-engineered pigs (α1,3-galactosyltransferase gene-knockout, GTKO), n = 1; GTKO pigs transgenic for human CD46, n = 7) and a clinically-acceptable immunosuppressive regimen. Biopsies were obtained from the WT pig liver pre-Tx and at 30 min, 1, 2, 3, 4 and 5 h post-transplantation. Biopsies of genetically-engineered livers were obtained pre-Tx, 2 h after reperfusion and at necropsy (4–7 days after transplantation). Tissues were examined by light, confocal, and electron microscopy. All major native organs were also examined. The WT pig liver underwent hyperacute rejection. After genetically-engineered pig liver transplantation, hyperacute rejection did not occur. Survival was limited to 4–7 days due to repeated spontaneous bleeding in the liver and native organs (as a result of profound thrombocytopenia) which necessitated euthanasia. At 2 h, graft histology was largely normal. At necropsy, genetically-engineered pig livers showed hemorrhagic necrosis, platelet aggregation, platelet-fibrin thrombi, monocyte/macrophage margination mainly in liver sinusoids, and vascular endothelial cell hypertrophy, confirmed by confocal and electron microscopy. Immunohistochemistry showed minimal deposition of IgM, and almost absence of IgG, C3, C4d, C5b-9, and of a cellular infiltrate, suggesting that neither antibody- nor cell-mediated rejection played a major role.
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Affiliation(s)
- Burcin Ekser
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
- Department of Surgery, Transplantation and Advanced Technologies, Vascular Surgery and Organ Transplant Unit, University Hospital of Catania, Catania, Italy
| | - Edwin Klein
- Division of Laboratory Animal Resources, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Jing He
- Division of Immunogenetics, Department of Pediatrics, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Donna B. Stolz
- Department of Cell Biology and Physiology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Gabriel J. Echeverri
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
- Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Palermo, Italy
| | - Cassandra Long
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Chih Che Lin
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Mohamed Ezzelarab
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Hidetaka Hara
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Massimiliano Veroux
- Department of Surgery, Transplantation and Advanced Technologies, Vascular Surgery and Organ Transplant Unit, University Hospital of Catania, Catania, Italy
| | - David Ayares
- Revivicor Inc., Blacksburg, Virginia, United States of America
| | - David K. C. Cooper
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
- * E-mail:
| | - Bruno Gridelli
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
- Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Palermo, Italy
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Abstract
Cross-species transplantation (xenotransplantation) offers the prospect of an unlimited supply of organs and cells for clinical transplantation, thus resolving the critical shortage of human tissues that currently prohibits a majority of patients on the waiting list from receiving transplants. Between the 17th and 20th centuries, blood was transfused from various animal species into patients with a variety of pathological conditions. Skin grafts were carried out in the 19th century from a variety of animals, with frogs being the most popular. In the 1920s, Voronoff advocated the transplantation of slices of chimpanzee testis into aged men whose "zest for life" was deteriorating, believing that the hormones produced by the testis would rejuvenate his patients. Following the pioneering surgical work of Carrel, who developed the technique of blood vessel anastomosis, numerous attempts at nonhuman primate organ transplantation in patients were carried out in the 20th century. In 1963-1964, when human organs were not available and chronic dialysis was not yet in use, Reemtsma transplanted chimpanzee kidneys into 13 patients, one of whom returned to work for almost 9 months before suddenly dying from what was believed to be an electrolyte disturbance. The first heart transplant in a human ever performed was by Hardy in 1964, using a chimpanzee heart, but the patient died within 2 hours. Starzl carried out the first chimpanzee-to-human liver transplantation in 1966; in 1992, he obtained patient survival for 70 days following a baboon liver transplant. With the advent of genetic engineering and cloning technologies, pigs are currently available with a number of different manipulations that protect their tissues from the human immune response, resulting in increasing pig graft survival in nonhuman primate models. Genetically modified pigs offer hope of a limitless supply of organs and cells for those in need of a transplant.
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Affiliation(s)
- David K C Cooper
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh Medical Center. Pittsburgh, Pennsylvania
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Ekser B, Gridelli B, Veroux M, Cooper DK. Clinical pig liver xenotransplantation: how far do we have to go? Xenotransplantation 2011; 18:158-67. [DOI: 10.1111/j.1399-3089.2011.00642.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Although corneal transplantation (Tx) is readily available in the United States and certain other regions of the developed world, the need for human donor corneas worldwide far exceeds supply. There is currently renewed interest in the possibility of using corneas from other species, especially pigs, for Tx into humans (xeno-Tx). The biomechanical properties of human and pig corneas are similar. Studies in animal models of corneal xeno-Tx have documented both humoral and cellular immune responses that play roles in xenograft rejection. The results obtained from the Tx of corneas from wild-type (ie, genetically unmodified) pigs into nonhuman primates have been surprisingly good and encouraging. Recent progress in the genetic manipulation of pigs has led to the prospect that the remaining immunological barriers will be overcome. There is every reason for optimism that corneal xeno-Tx will become a clinical reality within the next few years.
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Hara H, Campanile N, Tai HC, Long C, Ekser B, Yeh P, Welchons D, Ezzelarab M, Ayares D, Cooper DKC. An in vitro model of pig liver xenotransplantation--pig complement is associated with reduced lysis of wild-type and genetically modified pig cells. Xenotransplantation 2011; 17:370-8. [PMID: 20955293 DOI: 10.1111/j.1399-3089.2010.00602.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND After pig liver transplantation in humans, the graft will produce pig complement (C). We investigated in vitro the lysis of wild-type (WT), α1,3-galactosyltransferase gene-knockout (GTKO), and CD46 transgenic (CD46) pig peripheral blood mononuclear cells (PBMC) caused by human anti-pig antibodies (Abs) + pig C. METHODS Human serum IgM/IgG binding to WT and GTKO PBMC was determined by flow cytometry, and lysis of pig PBMC by a C-dependent cytotoxicity assay using (i) human serum (human Abs + C), (ii) GTKO pig serum (anti-Gal Abs + pig C), (iii) heat-inactivated human serum (human Abs) + rabbit C, or (iv) human Abs + pig C (serum). RESULTS Binding of human IgM and IgG to GTKO PBMC was less than to WT PBMC (P < 0.05). In the presence of human Abs, lysis of WT and GTKO PBMC by rabbit C was 87 and 13%, respectively (WT vs. GTKO, P < 0.01), but was only 37 and 0.4% in the presence of pig C (WT vs. GTKO, P < 0.05). Human/rabbit C-induced lysis was greater than pig C-induced lysis for both WT and GTKO PBMC. CD46 pig PBMC reduced rabbit/human C- and pig C-mediated lysis (P < 0.05). CONCLUSIONS Pig livers, particularly from GTKO and CD46 pigs, are likely to have an immunologic advantage over other organs after transplantation into humans. In the absence of pig antibodies directed to human tissues, pig complement is unlikely to cause problems after liver xenotransplantation, especially if GTKO/CD46 pigs are used as the source of the livers.
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Affiliation(s)
- Hidetaka Hara
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA 15261, USA.
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Gock H, Nottle M, Lew AM, d'Apice AJ, Cowan P. Genetic modification of pigs for solid organ xenotransplantation. Transplant Rev (Orlando) 2011; 25:9-20. [DOI: 10.1016/j.trre.2010.10.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Revised: 08/13/2010] [Accepted: 10/01/2010] [Indexed: 10/18/2022]
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Abstract
The author pays tribute to those who stimulated him to follow a career in clinical cardiothoracic surgery and experimental transplantation. Highlights of his career have been in contributing to (i) the first hypothermic perfusion storage of the donor heart to be used successfully in clinical practice, (ii) hormonal therapy in the management of the brain-dead potential organ donor, (iii) the identification of Gal alpha 1,3Gal as the major antigenic target for primate natural anti-pig antibodies, (iv) the 2- to 6-month survival of alpha1,3-galactosyltransferase gene-knockout hearts transplanted into baboons, and (v) the 3- to 12-month normoglycemia following the transplantation of islets from CD46-transgenic pigs into diabetic monkeys. Many friends have been made through a mutual interest in transplantation, particularly through the activities of the International Xenotransplantation Association (IXA). The author thanks the many mentors, colleagues, and research fellows with whom it has been his great privilege and pleasure to work during the past several decades, and readily acknowledges that it is largely their contributions that have enabled him to receive the honor of Honorary Membership of the IXA.
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Affiliation(s)
- David K C Cooper
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA 15261, USA.
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Cooper DKC, Ayares D. The immense potential of xenotransplantation in surgery. Int J Surg 2010; 9:122-9. [PMID: 21059418 DOI: 10.1016/j.ijsu.2010.11.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Accepted: 11/02/2010] [Indexed: 01/28/2023]
Abstract
There is a limited availability of deceased human organs and cells for the purposes of clinical transplantation. Genetically-engineered pigs may provide an alternative source. Although several immune barriers need to be overcome, considerable progress has been made in experimental models in recent years, largely through the increasing availability of pigs with new genetic modifications. Pig heterotopic heart graft survival in nonhuman primates has extended for 8 months, with orthotopic grafts supporting life for almost 2 months. Life-supporting kidney transplants have functioned for almost 3 months. The current barriers are related to coagulation dysfunction between pig and primate that results in thrombotic microangiopathy and/or a consumptive coagulopathy, which may in part be related to molecular incompatibilities in the coagulation systems of pigs and primates. Current efforts are concentrated on genetically-modifying the organ- or islet-source pigs by the introduction of 'anticoagulant' or 'anti-thrombotic' genes to provide protection from the recipient coagulation cascade and platelet activation. Progress with pig islet xenotransplantation has been particularly encouraging with complete control of glycemia in diabetic monkeys extending in one case for >12 months. Other areas where experimental data suggest the possibility of early clinical trials are corneal xenotransplantation and pig neuronal cell xenotransplantation, for example, in patients with Parkinson's disease. With the speed of advances in genetic engineering increasing steadily, it is almost certain that the remaining problems will be overcome within the foreseeable future, and clinical allotransplantation will eventually become of historical interest only.
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Affiliation(s)
- David K C Cooper
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, BST W1543, 200 Lothrop Street, Pittsburgh, PA 15261, USA.
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60
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Hara H, Cooper DKC. The immunology of corneal xenotransplantation: a review of the literature. Xenotransplantation 2010; 17:338-49. [DOI: 10.1111/j.1399-3089.2010.00608.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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61
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Ekser B, Echeverri GJ, Hassett AC, Yazer MH, Long C, Meyer M, Ezzelarab M, Lin CC, Hara H, van der Windt DJ, Dons EM, Phelps C, Ayares D, Cooper DKC, Gridelli B. Hepatic function after genetically engineered pig liver transplantation in baboons. Transplantation 2010; 90:483-93. [PMID: 20606605 PMCID: PMC2933286 DOI: 10.1097/tp.0b013e3181e98d51] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND If "bridging" to allo-transplantation (Tx) is to be achieved by a pig liver xenograft, adequate hepatic function needs to be assured. METHODS We have studied hepatic function in baboons after Tx of livers from alpha1,3-galactosyltransferase gene-knockout (GTKO, n=1) or GTKO pigs transgenic for CD46 (GTKO/CD46, n=5). Monitoring was by liver function tests and coagulation parameters. Pig-specific proteins in the baboon serum/plasma were identified by Western blot. In four baboons, coagulation factors were measured. The results were compared with values from healthy humans, baboons, and pigs. RESULTS Recipient baboons died or were euthanized after 4 to 7 days after internal bleeding associated with profound thrombocytopenia. However, parameters of liver function, including coagulation, remained in the near-normal range, except for some cholestasis. Western blot demonstrated that pig proteins (albumin, fibrinogen, haptoglobin, and plasminogen) were produced by the liver from day 1. Production of several pig coagulation factors was confirmed. CONCLUSIONS After the Tx of genetically engineered pig livers into baboons (1) many parameters of hepatic function, including coagulation, were normal or near normal; (2) there was evidence for production of pig proteins, including coagulation factors; and (3) these appeared to function adequately in baboons although interspecies compatibility of such proteins remains to be confirmed.
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Affiliation(s)
- Burcin Ekser
- Thomas E Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
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Transgenic pigs for xenotransplantation: selection of promoter sequences for reliable transgene expression. Curr Opin Organ Transplant 2010; 15:201-6. [PMID: 20061949 DOI: 10.1097/mot.0b013e328336ba4a] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW Appropriate expression of immunomodulatory and anticoagulant proteins on endothelial cells is essential to prevent rejection of vascularized porcine organs after transplantation into primates. Here, we review the promoter sequences used for the establishment of transgenic pigs, as organ donors for xenotransplantation. RECENT FINDINGS Transgenic pigs were produced using viral, chicken, mouse, human, and porcine promoter sequences with ubiquitous or cell type-specific activity. In addition to the expression of human complement regulatory proteins, which were efficient to prevent hyperacute rejection of pig-to-primate xenografts, novel transgenes, targeting cellular rejection mechanisms, abnormal-blood coagulation, or the risk of viral transmission, have been published or announced in preliminary reports. SUMMARY Accurate spatiotemporal expression of immunomodulatory and anticoagulant proteins on the endothelial cells of transgenic pigs is required for the successful xenotransplantation of vascularized organs into primates. Targeting transgene expression specifically to the cells critical for xenograft rejection may eliminate potential side effects of ubiquitous expression. Comparison of regulatory sequences from various species indicates that carefully selected porcine promoter sequences may be beneficial to achieve this aim.
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63
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Cooper DK, Hara H, Yazer M. Genetically Engineered Pigs as a Source for Clinical Red Blood Cell Transfusion. Clin Lab Med 2010; 30:365-80. [DOI: 10.1016/j.cll.2010.02.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Ekser B, Cooper DKC. Overcoming the barriers to xenotransplantation: prospects for the future. Expert Rev Clin Immunol 2010; 6:219-30. [PMID: 20402385 PMCID: PMC2857338 DOI: 10.1586/eci.09.81] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cross-species transplantation (xenotransplantation) has immense potential to solve the critical need for organs, tissues and cells for clinical transplantation. The increasing availability of genetically engineered pigs is enabling progress to be made in pig-to-nonhuman primate experimental models. Potent pharmacologic immunosuppressive regimens have largely prevented T-cell rejection and a T-cell-dependent elicited antibody response. However, coagulation dysfunction between the pig and primate is proving to be a major problem, and this can result in life-threatening consumptive coagulopathy. This complication is unlikely to be overcome until pigs expressing a human 'antithrombotic' or 'anticoagulant' gene, such as thrombomodulin, tissue factor pathway inhibitor or CD39, become available. Progress in islet xenotransplantation has been more encouraging, and diabetes has been controlled in nonhuman primates for periods in excess of 6 months, although this has usually been achieved using immunosuppressive protocols that might not be clinically applicable. Further advances are required to overcome the remaining barriers.
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Affiliation(s)
- Burcin Ekser
- Thomas E Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA, USA, and Department of Surgery and Organ Transplantation, University of Padua, Padua, Italy
| | - David KC Cooper
- Thomas E Starzl Transplantation Institute, University of Pittsburgh Medical Center, Starzl Biomedical Science Tower, W1543, 200 Lothrop Street, Pittsburgh, PA 15261, USA, Tel.: +1 412 383 6961, Fax: +1 412 624 1172,
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Ekser B, Long C, Echeverri GJ, Hara H, Ezzelarab M, Lin CC, de Vera ME, Wagner R, Klein E, Wolf RF, Ayares D, Cooper DKC, Gridelli B. Impact of thrombocytopenia on survival of baboons with genetically modified pig liver transplants: clinical relevance. Am J Transplant 2010; 10:273-85. [PMID: 20041862 DOI: 10.1111/j.1600-6143.2009.02945.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A lack of deceased human donor livers leads to a significant mortality in patients with acute-on-chronic or acute (fulminant) liver failure or with primary nonfunction of an allograft. Genetically engineered pigs could provide livers that might bridge the patient to allotransplantation. Orthotopic liver transplantation in baboons using livers from alpha1,3-galactosyltransferase gene-knockout (GTKO) pigs (n = 2) or from GTKO pigs transgenic for CD46 (n = 8) were carried out with a clinically acceptable immunosuppressive regimen. Six of 10 baboons survived for 4-7 days. In all cases, liver function was adequate, as evidenced by tests of detoxification, protein synthesis, complement activity and coagulation parameters. The major problem that prevented more prolonged survival beyond 7 days was a profound thrombocytopenia that developed within 1 h after reperfusion, ultimately resulting in spontaneous hemorrhage at various sites. We postulate that this is associated with the expression of tissue factor on platelets after contact with pig endothelium, resulting in platelet and platelet-peripheral blood mononuclear cell(s) aggregation and deposition of aggregates in the liver graft, though we were unable to confirm this conclusively. If this problem can be resolved, we would anticipate that a pig liver could provide a period during which a patient in liver failure could be successfully bridged to allotransplantation.
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Affiliation(s)
- B Ekser
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
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Miyagawa S, Yamamoto A, Matsunami K, Wang D, Takama Y, Ueno T, Okabe M, Nagashima H, Fukuzawa M. Complement regulation in the GalT KO era. Xenotransplantation 2010; 17:11-25. [DOI: 10.1111/j.1399-3089.2010.00569.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Klymiuk N, Aigner B, Brem G, Wolf E. Genetic modification of pigs as organ donors for xenotransplantation. Mol Reprod Dev 2009; 77:209-21. [DOI: 10.1002/mrd.21127] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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van der Windt DJ, Bottino R, Casu A, Campanile N, Smetanka C, He J, Murase N, Hara H, Ball S, Loveland BE, Ayares D, Lakkis FG, Cooper DKC, Trucco M. Long-term controlled normoglycemia in diabetic non-human primates after transplantation with hCD46 transgenic porcine islets. Am J Transplant 2009; 9:2716-26. [PMID: 19845582 DOI: 10.1111/j.1600-6143.2009.02850.x] [Citation(s) in RCA: 198] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Xenotransplantation of porcine islets into diabetic non-human primates is characterized by (i) an initial massive graft loss possibly due to the instant blood-mediated inflammatory reaction and (ii) the requirement of intensive, clinically unfriendly immunosuppressive therapy. We investigated whether the transgenic expression of a human complement-regulatory protein (hCD46) on porcine islets would improve the outcome of islet xenotransplantation in streptozotocin-induced diabetic Cynomolgus monkeys. Immunosuppression consisted of thymoglobulin, anti-CD154 mAb for costimulation blockade, and mycophenolate mofetil. Following the transplantation of islets from wild-type pigs (n = 2) or from 1,3-galactosyltransferase gene-knockout pigs (n = 2), islets survived for a maximum of only 46 days, as evidenced by return to hyperglycemia and the need for exogenous insulin therapy. The transplantation of islets from hCD46 pigs resulted in graft survival and insulin-independent normoglycemia in four of five monkeys for the 3 months follow-up of the experiment. One normalized recipient, selected at random, was followed for >12 months. Inhibition of complement activation by the expression of hCD46 on the pig islets did not substantially reduce the initial loss of islet mass, rather was effective in limiting antibody-mediated rejection. This resulted in a reduced need for immunosuppression to preserve a sufficient islet mass to maintain normoglycemia long-term.
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Affiliation(s)
- D J van der Windt
- Division of Immunogenetics, Department of Pediatrics, Children's Hospital of Pittsburgh, of UPMC Pittsburgh, PA, USA
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Le Friec G, Kemper C. Complement: coming full circle. Arch Immunol Ther Exp (Warsz) 2009; 57:393-407. [PMID: 19866344 DOI: 10.1007/s00005-009-0047-4] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2009] [Accepted: 06/01/2009] [Indexed: 02/04/2023]
Abstract
The complement system has long been known to be a major element of innate immunity. Traditionally, it was regarded as the first line of defense against invading pathogens, leading to opsonization and phagocytosis or the direct lysis of microbes. However, from the second half of the twentieth century on, it became clear that complement is also intimately involved in the induction and "fine tuning" of adaptive B- and T-cell responses as well as lineage commitment. This growing recognition of the complement system's multifunctional role in immunity is consistent with the recent paradigm that complement is also necessary for the successful contraction of an adaptive immune response. This review aims at giving a condensed overview of complement's rise from a simple innate stop-and-go system to an essential and efficient participant in general immune homeostasis and acquired immunity.
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Affiliation(s)
- Gaëlle Le Friec
- King's College London, MRC Centre for Transplantation, London SE1 9RT, UK
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Long C, Hara H, Pawlikowski Z, Koike N, d'Arville T, Yeh P, Ezzelarab M, Ayares D, Yazer M, Cooper DKC. Genetically engineered pig red blood cells for clinical transfusion: initial in vitro studies. Transfusion 2009; 49:2418-29. [PMID: 19624491 DOI: 10.1111/j.1537-2995.2009.02306.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Pigs are a potential source of red blood cells (RBCs) and could resolve the shortage of human blood for transfusion. This study investigated in vitro the compatibility of genetically engineered pig RBCs (pRBCs) with the human innate immune response. STUDY DESIGN AND METHODS Human volunteers of all ABO blood types were sources of sera and those of O blood type were sources of circulating monocytes/macrophages. RBCs from ABO-compatible (ABO-C) and ABO-incompatible (ABO-I) humans and wild-type (WT) and alpha-1,3-galactosyltransferase gene-knockout (GTKO) pigs were tested for hemagglutination, immunoglobulin (Ig)M/IgG antibody binding, and complement-dependent cytotoxicity (CDC) using human sera. Phagocytosis of RBCs by human monocyte-derived macrophages was measured by coculture in the absence or presence of pooled human O serum. RESULTS RBCs showed significant differences (p < 0.01) with regard to hemagglutination, IgM and IgG binding, and CDC (ABO-C < GTKO < ABO-I < WT). In the absence of pooled human O serum (antibodies), there was no phagocytosis of any RBCs; in the presence of serum (antibodies), phagocytosis of ABO-I RBCs was greater than of WT (p < 0.01), which in turn was greater than of GTKO RBCs (p < 0.05). CONCLUSIONS GTKO RBCs were significantly more compatible than ABO-I and WT RBCs, but were not comparable to ABO-C combinations. In the presence of antibody, human monocyte-derived macrophages phagocytosed ABO-I RBC/sera combinations more efficiently than pRBCs. These observations contribute to our ultimate goal of using genetically engineered pRBCs for clinical blood transfusion. However, pigs will require other modifications or manipulations if they are to become suitable for human transfusion.
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Affiliation(s)
- Cassandra Long
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Starzl Biomedical Science Tower, W1540, 200 Lothrop Street, Pittsburgh, PA 15261, USA
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71
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Arlaud JJ, Baker L, Williams RL, French AJ. Oestrous synchronization, ovarian superovulation and intraspecific transfers from a closed breeding colony of inbred SLA miniature pigs. Reprod Domest Anim 2009; 45:951-8. [PMID: 19473311 DOI: 10.1111/j.1439-0531.2009.01467.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The inbred SLA miniature pig is a unique animal model developed for organ transplantation studies and pre-clinical experimental purposes. Reported oestrous synchronization and superovulation treatments were examined in two SLA haplotypes (AA and DD) to allow collection of embryos for both practical embryo transfer and experimental technologies from a closed breeding colony. Pre-puberal miniature pigs were poor responders to oestrous synchronization treatments, while post-puberal sows were equivalent to commercial sows. Following superovulation, the ovulation number (corpora .hemorrhagica) was higher (p < 0.05) in the cycling sows when compared with non-cycling sows. Ovulations were equivalent to commercial pre-puberal gilts and non-cycling sows (p > 0.05). No difference in ovulation number between haplotypes was observed, which differs from the previous report (DD>AA). Collection of zygotes for pronuclear injection was the highest in the non-cycling post-puberal miniature pig group (p < 0.05), although significantly lower when compared with the commercial pig treatment groups (p < 0.05). The incidence of cystic endometrial hyperplasia in our colony was equivalent to rates observed in commercial pigs. Pronuclear visualization following centrifugation was the highest in the non-cycling miniature sow group and approximates to about 25% of ovulations and about half the rate observed in the commercial pigs (50%). Miniature pig embryos transferred between SLA haplotypes and transfer of DD embryos to commercial pigs resulted in live births at a higher efficiency than previously reported. This study demonstrates the feasibility of undertaking assisted reproductive technologies in a closed breeding colony of inbred SLA miniature pigs without compromise to the breeding programmes.
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Affiliation(s)
- J J Arlaud
- Monash Institute of Medical Research, and Melbourne StemCell Sciences Australia Limited, Monash STRIP, Monash University, Melbourne, Australia
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72
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73
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Cowan PJ, d'Apice AJF. Complement activation and coagulation in xenotransplantation. Immunol Cell Biol 2009; 87:203-8. [DOI: 10.1038/icb.2008.107] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Peter J Cowan
- Immunology Research Centre, St Vincent's Hospital Melbourne Melbourne Victoria Australia
- Department of Medicine, University of Melbourne Melbourne Victoria Australia
| | - Anthony JF d'Apice
- Immunology Research Centre, St Vincent's Hospital Melbourne Melbourne Victoria Australia
- Department of Medicine, University of Melbourne Melbourne Victoria Australia
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74
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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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75
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Honorary Membership of International Xenotransplantation Association Conferred Upon Professor Ian F C McKenzie (September 18, 2007). Xenotransplantation 2008; 15:285-9. [DOI: 10.1111/j.1399-3089.2008.00491.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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76
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Hara H, Long C, Lin YJ, Tai HC, Ezzelarab M, Ayares D, Cooper DKC. In vitro investigation of pig cells for resistance to human antibody-mediated rejection. Transpl Int 2008; 21:1163-74. [PMID: 18764834 DOI: 10.1111/j.1432-2277.2008.00736.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Although human complement-dependent cytotoxicity (CDC) of alpha1,3-galactosyltransferase gene-knockout (GTKO) pig cells is significantly weaker than that of wild-type (WT) cells, successful xenotransplantation will require pigs with multiple genetic modifications. Sera from healthy humans were tested by (i) flow cytometry for binding of IgM/IgG, and (ii) CDC assay against peripheral blood mononuclear cells and porcine aortic endothelial cells from five types of pig - WT, GTKO, GTKO transgenic for H-transferase (GTKO/HT), WT transgenic for human complement regulatory protein CD46 (CD46) and GTKO/CD46. There was significantly higher mean IgM/IgG binding to WT and CD46 cells than to GTKO, GTKO/HT, and GTKO/CD46, but no difference between GTKO, GTKO/HT, and GTKO/CD46 cells. There was significantly higher mean CDC to WT than to GTKO, GTKO/HT, CD46, and GTKO/CD46 cells, but no difference between GTKO and GTKO/HT. Lysis of GTKO/CD46 cells was significantly lower than that of GTKO or CD46 cells. CD46 expression provided partial protection against serum from a baboon sensitized to a GTKO pig heart. GTKO/CD46 cells were significantly resistant to lysis by human serum and sensitized baboon serum. In conclusion, the greatest protection from CDC was obtained by the combination of an absence of Gal expression and the presence of CD46 expression, but the expression of HT appeared to offer no advantage over GTKO. Organs from GTKO/CD46 pigs are likely to be significantly less susceptible to CDC.
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Affiliation(s)
- Hidetaka Hara
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
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77
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Cornell LD, Smith RN, Colvin RB. Kidney transplantation: mechanisms of rejection and acceptance. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2008; 3:189-220. [PMID: 18039144 DOI: 10.1146/annurev.pathmechdis.3.121806.151508] [Citation(s) in RCA: 153] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We describe the molecular and cellular mechanisms believed to be responsible for the rejection of renal allografts, including acute T cell-mediated rejection, acute antibody-mediated (humoral) rejection, rejection mediated by the innate immune system, and chronic rejection. We present mechanisms of graft acceptance, including accommodation, regulation, and tolerance. Studies in animals have replicated many pathologic features of acute and chronic rejection. We illuminate the pathogenesis of human pathology by reflection from experimental models.
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Affiliation(s)
- Lynn D Cornell
- Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
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78
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Griesche N, Zikos D, Witkowski P, Nitsche A, Ellerbrok H, Spiller OB, Pauli G, Biere B. Growth characteristics of human adenoviruses on porcine cell lines. Virology 2008; 373:400-10. [PMID: 18191169 DOI: 10.1016/j.virol.2007.12.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2007] [Revised: 11/30/2007] [Accepted: 12/14/2007] [Indexed: 10/22/2022]
Abstract
Human adenoviruses (hAdV) have been recognized as a highly prevalent virus family causing severe disease in immunocompromised patients. In xenotransplantation the xenograft therefore will be exposed to these viruses, which in case of its infection might contribute to posttransplant complications. To evaluate the susceptibility of porcine cells for hAdV, we infected the porcine cell line POEK with seven serotypes representing all six hAdV species. Additionally, a second porcine cell line (ST) was infected with two serotypes. Viral replication of serotypes varied: porcine cells were fully permissive for serotypes 1, 4 and 17, semi-permissive for 11 and 21, and non-permissive for 31 and 40. Furthermore, we demonstrated the interaction of serotype 1 with the porcine homologue of the coxsackie-adenovirus receptor, the receptor used by many hAdV serotypes for cell attachment. Thus, various adenovirus types of different hAdV species may be capable of infecting different porcine tissue types.
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Affiliation(s)
- Nadine Griesche
- Robert Koch-Institut, Zentrum für Biologische Sicherheit 1, Nordufer 20, 13353 Berlin, Germany
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79
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Affiliation(s)
- Mauro S Sandrin
- Department of Surgery, The University of Melbourne, Austin Health/Northern Health, Heidelberg, Victoria, Australia.
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80
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The impact of the α1,3-galactosyltransferase gene knockout pig on xenotransplantation. Curr Opin Organ Transplant 2007. [DOI: 10.1097/mot.0b013e328028fdd8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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81
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Histopathology of discordant xenotransplantation. Curr Opin Organ Transplant 2006. [DOI: 10.1097/01.mot.0000218931.19773.f7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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82
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83
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Kim DD, Song WC. Membrane complement regulatory proteins. Clin Immunol 2005; 118:127-36. [PMID: 16338172 DOI: 10.1016/j.clim.2005.10.014] [Citation(s) in RCA: 252] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2005] [Accepted: 10/28/2005] [Indexed: 12/12/2022]
Abstract
A number of proteins anchored on the cell surface function to protect host tissues from bystander injury when complement is activated. In humans, they include decay-accelerating factor (DAF, CD55), membrane cofactor protein (MCP, CD46), complement receptor 1 (CR1, CD35) and CD59. Although disease conditions directly attributable to abnormal function of these proteins are relatively rare, it has become evident from recent studies using animal models that membrane complement regulatory proteins are important modulators of tissue injury in many autoimmune and inflammatory disease settings. Evidence is also emerging to support a role of these proteins in regulating cellular immunity. In this article, we highlight recent advances on the in vivo biology of membrane complement regulatory proteins and discuss their relevance in human disease pathogenesis and therapeutics.
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Affiliation(s)
- David D Kim
- Institute for Translational Medicine, University of Pennsylvania School of Medicine, Rm 1254 BRBII/III, 421 Curie Blvd, Philadelphia, PA 19104, USA
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84
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Milland J, Christiansen D, Sandrin MS. α1,3‐Galactosyltransferase knockout pigs are available for xenotransplantation: Are glycosyltransferases still relevant? Immunol Cell Biol 2005; 83:687-93. [PMID: 16266321 DOI: 10.1111/j.1440-1711.2005.01398.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In the early 1990s, the Galalpha(1,3)Gal carbohydrate linkage was found to be the major xenoepitope causing hyperacute rejection. This carbohydrate, the antibodies that bind to it, and the enzyme that produces it (alpha1,3-galactosyltransferase) were the foci of research by many groups. Nearly a decade later, alpha1,3-galactosyltransferase knockout pigs were finally produced; hyperacute rejection could be avoided in these pigs. Having achieved this goal, enthusiasm declined for the study of glycosyltransferases and their carbohydrate products. To examine whether this decline was premature, we evaluate whether gene deletion has indeed solved the initial rejection problem or, in fact, created new problems. This review addresses this by examining the impact of the gene deletion on cell surface carbohydrate. Surprisingly, Galalpha(1,3)Gal is still present in alpha1,3-galactosyltransferase knockout animals: it is possibly synthesized on lipid by iGb3 synthase. Furthermore, removal of alphaGal resulted in the exposure of the N-acetyllactosamine epitope. This exposed epitope can bind natural antibodies and perhaps should be capped by transgenic expression of another transferase. We believe the continued study of glycosyltransferases is essential to examine the new issues raised by the deletion of alpha1,3-galactosyltransferase.
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Affiliation(s)
- Julie Milland
- The Austin Research Institute, Austin Health, Melbourne, Victoria, Australia
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85
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Webster NL, Forni M, Bacci ML, Giovannoni R, Razzini R, Fantinati P, Zannoni A, Fusetti L, Dalprà L, Bianco MR, Papa M, Seren E, Sandrin MS, Mc Kenzie IFC, Lavitrano M. Multi-transgenic pigs expressing three fluorescent proteins produced with high efficiency by sperm mediated gene transfer. Mol Reprod Dev 2005; 72:68-76. [PMID: 15906394 DOI: 10.1002/mrd.20316] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Multi-gene transgenic pigs would be of benefit for large animal models in medical, agricultural, and pharmaceutical applications; in particular for xenotransplantation, where extensive genetic manipulation of donor pigs is required to make them suitable for organ grafting to humans. We used the sperm mediated gene transfer (SMGT) method to produce with high efficiency multi-gene transgenic pigs using three genes coding for fluorescent proteins: enhanced blue (EBFP), green (EGFP), and red (DsRed2). All three fluorescent proteins were expressed in 171 out of 195 normally developed morula/blastocysts examined at day 6 post insemination (88%). Genomic DNA of 18 piglets born from two litters was screened by PCR, showing that all piglets were transgenic with at least one gene, 7/18 piglets were triple transgenic, 7/18 double transgenic, and 4/18 single transgenic. Fluorescence in situ hybridization (FISH) analysis revealed multiple sites of integration of the transgenes. RNA and protein expression was found in muscle, heart, liver, hair, and peripheral blood mononuclear cells (PBMCs). These results show that SMGT is an effective method for introducing multiple genes into pigs as shown by the simultaneous expression of three fluorescent proteins.
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Affiliation(s)
- Nicole L Webster
- The Austin Research Institute, Studley Road, Heidelberg, Victoria, Australia
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Buhler LH. Xenotransplantation literature update March-April, 2004. Xenotransplantation 2004; 11:383-6. [PMID: 15196137 DOI: 10.1111/j.1399-3089.2004.00150.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Leo H Buhler
- Associate Editor, Xenotransplantation, Department of Surgery, University Hospital Geneva, Geneva, Switzerland.
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