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Hoang TX, Kim JY. Regulatory macrophages in solid organ xenotransplantation. KOREAN JOURNAL OF TRANSPLANTATION 2023; 37:229-240. [PMID: 38115165 PMCID: PMC10772277 DOI: 10.4285/kjt.23.0055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 11/10/2023] [Accepted: 11/24/2023] [Indexed: 12/21/2023] Open
Abstract
Due to a critical organ shortage, pig organs are being explored for use in transplantation. Differences between species, particularly in cell surface glycans, can trigger elevated immune responses in xenotransplantation. To mitigate the risk of hyperacute rejection, genetically modified pigs have been developed that lack certain glycans and express human complement inhibitors. Nevertheless, organs from these pigs may still provoke stronger inflammatory and innate immune reactions than allotransplants. Dysregulation of coagulation and persistent inflammation remain obstacles in the transplantation of pig organs into primates. Regulatory macrophages (Mregs), known for their anti-inflammatory properties, could offer a potential solution. Mregs secrete interleukin 10 and transforming growth factor beta, thereby suppressing immune responses and promoting the development of regulatory T cells. These Mregs are typically induced via the stimulation of monocytes or macrophages with macrophage colony-stimulating factor and interferon gamma, and they conspicuously express the stable marker dehydrogenase/reductase 9. Consequently, understanding the precise mechanisms governing Mreg generation, stability, and immunomodulation could pave the way for the therapeutic use of Mregs generated in vitro. This approach has the potential to reduce the required dosages and durations of anti-inflammatory and immunosuppressive medications in preclinical and clinical settings.
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Affiliation(s)
- Thi Xoan Hoang
- Department of Life Science, Gachon University, Seongnam, Korea
| | - Jae Young Kim
- Department of Life Science, Gachon University, Seongnam, Korea
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2
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Morticelli L, Rossdam C, Cajic S, Böthig D, Magdei M, Tuladhar SR, Petersen B, Fischer K, Rapp E, Korossis S, Haverich A, Schnieke A, Niemann H, Buettner FFR, Hilfiker A. Genetic knockout of porcine GGTA1 or CMAH/GGTA1 is associated with the emergence of neo-glycans. Xenotransplantation 2023; 30:e12804. [PMID: 37148126 DOI: 10.1111/xen.12804] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 03/28/2023] [Accepted: 04/25/2023] [Indexed: 05/07/2023]
Abstract
BACKGROUND Pig-derived tissues could overcome the shortage of human donor organs in transplantation. However, the glycans with terminal α-Gal and Neu5Gc, which are synthesized by enzymes, encoded by the genes GGTA1 and CMAH, are known to play a major role in immunogenicity of porcine tissue, ultimately leading to xenograft rejection. METHODS The N-glycome and glycosphingolipidome of native and decellularized porcine pericardia from wildtype (WT), GGTA1-KO and GGTA1/CMAH-KO pigs were analyzed by multiplexed capillary gel electrophoresis coupled to laser-induced fluorescence detection. RESULTS We identified biantennary and core-fucosylated N-glycans terminating with immunogenic α-Gal- and α-Gal-/Neu5Gc-epitopes on pericardium of WT pigs that were absent in GGTA1 and GGTA1/CMAH-KO pigs, respectively. Levels of N-glycans terminating with galactose bound in β(1-4)-linkage to N-acetylglucosamine and their derivatives elongated by Neu5Ac were increased in both KO groups. N-glycans capped with Neu5Gc were increased in GGTA1-KO pigs compared to WT, but were not detected in GGTA1/CMAH-KO pigs. Similarly, the ganglioside Neu5Gc-GM3 was found in WT and GGTA1-KO but not in GGTA1/CMAH-KO pigs. The applied detergent based decellularization efficiently removed GSL glycans. CONCLUSION Genetic deletion of GGTA1 or GGTA1/CMAH removes specific epitopes providing a more human-like glycosylation pattern, but at the same time changes distribution and levels of other porcine glycans that are potentially immunogenic.
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Affiliation(s)
- Lucrezia Morticelli
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
| | - Charlotte Rossdam
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Samanta Cajic
- Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
- glyXera GmbH, Magdeburg, Germany
| | - Dietmar Böthig
- Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Mikhail Magdei
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
| | - Sugat Ratna Tuladhar
- Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Björn Petersen
- Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut, Mariensee/Neustadt am Ruebenberge, Germany
| | - Konrad Fischer
- Chair of Livestock Biotechnology, School of Life Sciences Weihenstephan, Technische Universität München, Freising, Germany
| | - Erdmann Rapp
- Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
- glyXera GmbH, Magdeburg, Germany
| | - Sotirios Korossis
- Cardiopulmonary Regenerative Engineering (CARE) Group, Centre for Biological Engineering (CBE), Wolfson School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Loughborough, UK
| | - Axel Haverich
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
- Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Angelika Schnieke
- Chair of Livestock Biotechnology, School of Life Sciences Weihenstephan, Technische Universität München, Freising, Germany
| | - Heiner Niemann
- Clinic for Gastroenterology, Hepatology & Endocrinology, Hannover Medical School (MHH), Hannover, Germany
| | - Falk F R Buettner
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Andres Hilfiker
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
- Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
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Obukhova P, Tsygankova S, Chinarev A, Shilova N, Nokel A, Kosma P, Bovin N. Are there specific antibodies against Neu5Gc epitopes in the blood of healthy individuals? Glycobiology 2021; 30:395-406. [PMID: 31897477 DOI: 10.1093/glycob/cwz107] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 12/18/2019] [Accepted: 12/18/2019] [Indexed: 12/11/2022] Open
Abstract
Strong discrepancies in published data on the levels and epitope specificities of antibodies against the xenogenic N-glycolyl forms of sialoglycans (Hanganutziu-Deicher Neu5Gcɑ2-3Galβ1-4Glc and related antigens) in healthy donors prompted us to carry out a systematic study in this area using the printed glycan array and other methods. This article summarizes and discusses our published and previously unpublished data, as well as publicly available data from the Consortium for Functional Glycomics. As a result, we conclude that (1) the level of antibodies referred to as anti-Neu5Gc in healthy individuals is low; (2) there are antibodies that seem to interact with Neu5Gc-containing epitopes, but in fact they recognize internal fragments of Neu5Gc-containing glycans (without sialic acids), which served as antigens in the assays used and; (3) a population capable of interacting specifically with Neu5Gc (it does not bind the corresponding NAc analogs) does exist, but it binds the monosaccharide Neu5Gc better than the entire glycans containing it. In other words, in healthy donors, there are populations of antibodies capable of binding the Neu5Gc monosaccharide or the inner core -Galβ1-4Glc, but very few true anti-Neu5Gcɑ2-3Galβ1-4Glc antibodies, i.e., antibodies capable of specifically recognizing the entire trisaccharide.
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Affiliation(s)
- Polina Obukhova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 16/10 Miklukho-Maklaya, 117997 Moscow, Russia.,Federal State Budget Institution, National Medical Research Center for Obstetrics, Gynecology and Perinatology named after Academician V.I. Kulakov of the Ministry of Healthcare of Russian Federation, 4 Oparin str., 117997, Moscow, Russia
| | - Svetlana Tsygankova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 16/10 Miklukho-Maklaya, 117997 Moscow, Russia
| | - Alexander Chinarev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 16/10 Miklukho-Maklaya, 117997 Moscow, Russia
| | - Nadezhda Shilova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 16/10 Miklukho-Maklaya, 117997 Moscow, Russia.,Federal State Budget Institution, National Medical Research Center for Obstetrics, Gynecology and Perinatology named after Academician V.I. Kulakov of the Ministry of Healthcare of Russian Federation, 4 Oparin str., 117997, Moscow, Russia.,Semiotik LLC, 16/10 Miklukho-Maklaya, 117997 Moscow, Russia
| | - Alexey Nokel
- Federal State Budget Institution, National Medical Research Center for Obstetrics, Gynecology and Perinatology named after Academician V.I. Kulakov of the Ministry of Healthcare of Russian Federation, 4 Oparin str., 117997, Moscow, Russia.,Semiotik LLC, 16/10 Miklukho-Maklaya, 117997 Moscow, Russia
| | - Paul Kosma
- Department of Chemistry, University of Natural Resources and Life Sciences, 18 Muthgasse, 1190 Vienna, Austria, and
| | - Nicolai Bovin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 16/10 Miklukho-Maklaya, 117997 Moscow, Russia.,Auckland University of Technology, 55 Wellesley Street East, 1010, Auckland, New Zealand
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Morticelli L, Magdei M, Tschalaki N, Petersen B, Haverich A, Hilfiker A. Generation of glycans depleted decellularized porcine pericardium, using digestive enzymatic supplements and enzymatic mixtures for food industry. Xenotransplantation 2021; 28:e12705. [PMID: 34227157 DOI: 10.1111/xen.12705] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 05/27/2021] [Accepted: 06/24/2021] [Indexed: 11/29/2022]
Abstract
BACKGROUND Xenogeneic pericardium has been used largely for various applications in cardiovascular surgery. Nevertheless, xenogeneic pericardial patches fail mainly due to their antigenic components. The xenoantigens identified as playing a major role in recipient immune response are the Galα1-3Gal (α-Gal) epitope, the non-human sialic acid N-glycolylneuraminic acid (Neu5Gc), and the porcine SDa antigen, associated with both proteins and lipids. The reduction in glycans from porcine pericardium might hinder or reduce the immunogenicity of xenogeneic scaffolds. METHODS Decellularized porcine pericardia were further treated at different time points and dilutions with digestive enzymatic supplements and enzymatic mixtures applied for food industry, for the removal of potentially immunogenic carbohydrates. Carbohydrates removal was investigated using up to 8 different lectin stains for the identification of N- and O-glycosylations, as well as glycolipids. Histoarchitectural changes in the ECM were assessed using Elastica van Gieson stain, whereas changes in mechanical properties were investigated via uniaxial tensile test and burst pressure test. RESULTS Tissues after enzymatic treatments showed a dramatic decrease in lectin stainings in comparison to tissues which were only decellularized. Histological assessment revealed cell-nuclei removal after decellularization. Some of the enzymatic treatments induced elastic lamellae disruption. Tissue strength decreased after enzymatic treatment; however, treated tissues showed values of burst pressure higher than physiological transvalvular pressures. CONCLUSIONS The application of these enzymatic treatments for tissue deglycosylation is totally novel, low cost, and appears to be very efficient for glycan removal. The immunogenic potential of treated tissues will be further investigated in subsequent studies, in vitro and in vivo.
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Affiliation(s)
- Lucrezia Morticelli
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany.,Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Mikhail Magdei
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany.,Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Negin Tschalaki
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany.,Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Björn Petersen
- Department of Biotechnology, Institute of Farm Animal Genetics, Friedrich-Loeffler-Institute, Mariensee, Neustadt, Germany
| | - Axel Haverich
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany.,Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Andres Hilfiker
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany.,Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
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Lee EJ, Lee H, Park EM, Kang HJ, Kim SJ, Park CG. Immunoglobulin M and Immunoglobulin G Subclass Distribution of Anti-galactose-Alpha-1,3-Galactose and Anti-N-Glycolylneuraminic Acid Antibodies in Healthy Korean Adults. Transplant Proc 2021; 53:1762-1770. [PMID: 33581850 DOI: 10.1016/j.transproceed.2021.01.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/19/2020] [Accepted: 01/08/2021] [Indexed: 12/19/2022]
Abstract
BACKGROUND Human preformed antibodies (Abs), anti-galactose-alpha-1,3-galactose (Gal) and anti-N-glycolylneuraminic acid (Neu5Gc), can react with porcine antigens of wild-type pigs. To provide basic population data of the Abs for potential application in clinical xenotransplantation, we developed enzyme-linked immunosorbent assay methods and investigated the serum titers of anti-Gal and anti-Neu5Gc Abs, including immunoglobulin (Ig) M and IgG along with its subclasses, in humans. METHODS Anti-Gal and anti-Neu5Gc Abs serum titers were measured in 380 healthy Korean adults using the in-house enzyme-linked immunosorbent assays. The frequency and median values of anti-Gal and anti-Neu5Gc were measured, and their class and subclass distribution were evaluated. RESULTS The detection frequencies of anti-Gal were 99.2%, 95.0%, 23.2%, 94.5%, 12.4%, and 3.4% for IgM, IgG, IgG1, IgG2, IgG3, and IgG4, respectively. The detection frequencies of anti-Neu5Gc Abs were 87.4%, 96.6%, 1.6%, 46.3%, 0.0%, and 0.0% for IgM, IgG, IgG1, IgG2, IgG3, and IgG4, respectively. The median values of anti-Gal IgM (1001.6 ng/mL) and IgG (1198.3 ng/mL) were significantly higher than those of anti-Neu5Gc Abs (IgM, 328.4 ng/mL; IgG, 194.7 ng/mL; P < .001). IgG2 titers of both anti-Gal and anti-Neu5Gc Abs correlated better with the IgG class than the titers of other IgG subclasses. CONCLUSIONS The titers of anti-Gal Abs were higher than those of anti-Neu5Gc Abs. IgG2 was the main IgG subclass in both anti-Gal and anti-Neu5Gc Abs. Variation in the titers of anti-Gal or anti-Neu5Gc Abs may partly explain the biological and immunologic changes that occur in recipients of xenotransplants.
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Affiliation(s)
- Eun Jin Lee
- Department of Laboratory Medicine, Hallym University College of Medicine, Dongtan Sacred Heart Hospital, Hwaseong-si, Republic of Korea
| | - Haneulnari Lee
- Department of Laboratory Medicine, Hallym University College of Medicine, Hallym, University Sacred Heart Hospital, Anyang-si, Republic of Korea
| | - Eun Mi Park
- Department of Laboratory Medicine, Hallym University College of Medicine, Hallym, University Sacred Heart Hospital, Anyang-si, Republic of Korea
| | - Hee Jung Kang
- Department of Laboratory Medicine, Hallym University College of Medicine, Hallym, University Sacred Heart Hospital, Anyang-si, Republic of Korea.
| | - Sang Joon Kim
- Department of Surgery, Myongji Hospital, Goyang-si, Republic of Korea
| | - Chung-Gyu Park
- Xenotransplantation Research Center, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Microbiology and Immunology, Department of Biomedical Sciences, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea; Institute of Endemic Diseases, Seoul National University College of Medicine, Seoul, Republic of Korea
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6
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Anti-pig IgE and IgA Antibodies in Naive Primates and Nonhuman Primates With Pig Xenografts. Transplantation 2021; 105:318-327. [PMID: 32796494 DOI: 10.1097/tp.0000000000003408] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND Natural preformed anti-pig IgM/IgG antibodies in primates play an important role in xenograft rejection. As it is not clear how IgE and IgA engage in the immune system in xenotransplantation, we investigated natural preformed and elicited anti-pig IgE/IgA in naive primates and after xenotransplantation in nonhuman primates. METHODS The binding of IgM/IgG/IgE/IgA antibodies to red blood cells (RBCs) from wild-type (WT), α1,3-galactosyltransferase gene-knockout (GTKO), and GTKO/cytidine monophospho-N-acetylneuraminic acid hydroxylase gene-knockout/β-1,4 N-acetylgalactosaminyltransferase 2 gene-knockout (ie, triple-knockout pigs) pigs were measured by flow cytometry in naive human (n = 50) and baboon (n = 14) sera. Antibody binding to WT and GTKO pig RBCs (pRBCs) was also measured in the sera of baboons (nonsensitized n = 7, sensitized n = 2) and rhesus monkeys (nonsensitized n = 2, sensitized n = 11) following WT or GTKO pig organ/tissue xenotransplantation. Deposition of IgM/IgG/IgE/IgA in the grafts was detected by immunohistochemistry. RESULTS The majority of humans had natural preformed IgM/IgG/IgE/IgA to WT and GTKO pRBCs. In contrast, IgM/IgG/IgE/IgA to triple-knockout pRBCs were present at lower levels and frequency (P < 0.01). Baboons also had IgM/IgG/IgE/IgA antibodies against WT pRBCs, but fewer to GTKO and triple-knockout (P < 0.01). After xenotransplantation into nonhuman primates, when IgM/IgG increased, IgE/IgA also increased, but to a lesser extent. In addition to IgM/IgG, IgE or IgA deposition was observed in rejected pig xenografts. CONCLUSIONS Primates develop serum anti-pig IgE/IgA antibodies both naturally and during xenograft rejection. The pathophysiological role, if any, of anti-pig IgE/IgA antibodies remains unknown.
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Dobrochaeva K, Khasbiullina N, Shilova N, Knirel Y, Obukhova P, Nokel A, Kunetskiy R, Tsygankova S, Bello-Gil D, Costa C, Mañez R, Bovin N. Specificity profile of αGal antibodies in αGalT KO mice as probed with comprehensive printed glycan array: Comparison with human anti-Galili antibodies. Xenotransplantation 2021; 28:e12672. [PMID: 33432698 DOI: 10.1111/xen.12672] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 12/16/2020] [Accepted: 12/24/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND The α1,3-galactosyltransferase gene-knockout (GalT KO) mice are able to produce natural anti-αGal antibodies apparently without any specific immunization. GalT KO mice are commonly used as a model immunological system for studying anti-αGal responses to Gal-positive xenografts in human. In this study, we compared the specificity of mouse and human αGal antibodies to realize the adequacy of the murine model. METHODS Using hapten-specific affinity chromatography antibodies against Galα1-3Galβ1-4GlcNAcβ epitope were isolated from both human and GalT KO mice blood sera. Specificity of isolated antibodies was determined using a printed glycan array (PGA) containing 400 mammalian glycans and 200 bacterial polysaccharides. RESULTS The quantity of isolated specific anti-Galα antibodies corresponds to a content of <0.2% of total Ig, which is an order of magnitude lower than that generally assumed for both human and murine peripheral blood immunoglobulin, with a high predominance of IgM over IgG (95% vs 5%). Analysis using a printed glycan array has demonstrated that (a) antibodies from both species bind not only the Galα1-3Galβ1-4GlcNAcβ epitope, but also unrelated glycans; (b) particularly, for human (but not mouse) antibodies the best binders appear to be bacterial polysaccharides; (c) the profile of mouse antibodies is broader, it is noteworthy that they recognize a variety of human blood group B epitopes and even glycans without the α-galactosyl residue. CONCLUSIONS We believe that the mouse model should be used cautiously in xenotransplantation experiments when the fine epitope specificity of antibodies is critical.
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Affiliation(s)
- Kira Dobrochaeva
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Nailya Khasbiullina
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia.,National Medical Research Center for Obstetrics, Gynecology and Perinatology named after Academician V.I. Kulakov of the Ministry of Healthcare of Russian Federation, Moscow, Russia
| | - Nadezhda Shilova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.,National Medical Research Center for Obstetrics, Gynecology and Perinatology named after Academician V.I. Kulakov of the Ministry of Healthcare of Russian Federation, Moscow, Russia.,Semiotik LLC, Moscow, Russia
| | - Yuriy Knirel
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Polina Obukhova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.,National Medical Research Center for Obstetrics, Gynecology and Perinatology named after Academician V.I. Kulakov of the Ministry of Healthcare of Russian Federation, Moscow, Russia
| | - Alexey Nokel
- National Medical Research Center for Obstetrics, Gynecology and Perinatology named after Academician V.I. Kulakov of the Ministry of Healthcare of Russian Federation, Moscow, Russia.,Semiotik LLC, Moscow, Russia
| | - Roman Kunetskiy
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Svetlana Tsygankova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Daniel Bello-Gil
- Infectious Pathology and Transplantation Division, Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Spain
| | - Cristina Costa
- Infectious Pathology and Transplantation Division, Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Spain
| | - Rafael Mañez
- Infectious Pathology and Transplantation Division, Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Spain
| | - Nicolai Bovin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.,School of Engineering, Computer & Mathematical Sciences, Auckland University of Technology, Auckland, New Zealand
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Kappler K, Restin T, Lasanajak Y, Smith DF, Bassler D, Hennet T. Limited Neonatal Carbohydrate-Specific Antibody Repertoire Consecutive to Partial Prenatal Transfer of Maternal Antibodies. Front Immunol 2020; 11:573629. [PMID: 33162988 PMCID: PMC7591393 DOI: 10.3389/fimmu.2020.573629] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 09/08/2020] [Indexed: 12/20/2022] Open
Abstract
Despite the prominence of carbohydrate-specific antibodies in human sera, data on their emergence and antigen specificities are limited. Whereas maternal IgG are transferred prenatally to the fetal circulation, IgM present in cord blood originate from fetal B lymphocytes. Considering the limited exposure of the fetus to foreign antigens, we assessed the repertoire of carbohydrate-specific antibodies in human cord blood and matched maternal blood samples using glycan arrays. Carbohydrate-specific IgM was absent in cord blood, whereas low cord blood IgG reactivity to glycans was detectable. Comparing IgG reactivities of matched pairs, we observed a general lack of correlation in the antigen specificity of IgG from cord blood and maternal blood due to a selective exclusion of most carbohydrate-specific IgG from maternofetal transfer. Given the importance of intestinal bacteria in inducing carbohydrate-specific antibodies, we analyzed global antibody specificities toward commensal bacteria. Similar IgG reactivities to specific Bacteroides species were detected in matched cord and maternal blood samples, thus pointing to an efficient maternal transfer of anti-microbial IgG. Due to the observed selectivity in maternofetal IgG transfer, the lack of fetal antibodies to carbohydrate epitopes is only partially compensated by maternal IgG, thus resulting in a weak response to carbohydrate antigens in neonates.
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Affiliation(s)
| | - Tanja Restin
- Institute of Physiology, University of Zurich, Zurich, Switzerland.,Department of Neonatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Yi Lasanajak
- Emory Comprehensive Glycomics Core, Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, United States
| | - David F Smith
- Emory Comprehensive Glycomics Core, Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, United States
| | - Dirk Bassler
- Department of Neonatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Thierry Hennet
- Institute of Physiology, University of Zurich, Zurich, Switzerland
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Schussler O, Lila N, Grau J, Ruel M, Lecarpentier Y, Carpentier A. Possible Link Between the ABO Blood Group of Bioprosthesis Recipients and Specific Types of Structural Degeneration. J Am Heart Assoc 2020; 9:e015909. [PMID: 32698708 PMCID: PMC7792238 DOI: 10.1161/jaha.119.015909] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Background Pigs/bovines share common antigens with humans: α-Gal, present in all pigs/bovines close to the human B-antigen; and AH-histo-blood-group antigen, identical to human AH-antigen and present only in some animals. We investigate the possible impact of patients' ABO blood group on bioprosthesis structural valve degeneration (SVD) through calcification/pannus/tears/perforations for patients ≤60 years at implantation. Methods and Results This was a single-center study (Paris, France) that included all degenerative bioprostheses explanted between 1985 and 1998, mostly porcine bioprostheses (Carpentier-Edwards second/third porcine bioprostheses) and some bovine bioprostheses. For the period 1998 to 2014, only porcine bioprostheses with longevity ≥13 years were included (total follow-up ≥29 years). Except for blood groups, important predictive factors for SVD were prospectively collected (age at implantation/longevity/number/site/sex/SVD types) and analyzed using logistic regression. All variables were available for 500 explanted porcine bioprostheses. By multivariate analyses, the A group was associated with an increased risk of: tears (odds ratio[OR], 1.61; P=0.026); pannus (OR, 1.5; P=0.054), pannus with tears (OR, 1.73; P=0.037), and tendency for lower risk of: calcifications (OR, 0.63; P=0.087) or isolated calcification (OR, 0.67; P=0.17). A-antigen was associated with lower risk of perforations (OR 0.56; P=0.087). B-group patients had an increased risk of: perforations (OR, 1.73; P=0.043); having a pannus that was calcified (OR, 3.0, P=0.025). B-antigen was associated with a propensity for calcifications in general (OR, 1.34; P=0.25). Conclusions Patient's ABO blood group is associated with specific SVD types. We hypothesize that carbohydrate antigens, which may or may not be common to patient and animal bioprosthetic tissue, will determine a patient's specific immunoreactivity with respect to xenograft tissue and thus bioprosthesis outcome in terms of SVD.
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Affiliation(s)
- Olivier Schussler
- Deparments of Cardiovascular Surgery and Cardiovascular Research Laboratory Geneva University Hospitals and Faculty of Medicine Geneva Switzerland.,Service de Chirurgie Thoracique Hôpitaux Universitaire de StrasbourgParis University Paris France
| | - Nermine Lila
- Biosurgical Research Lab (Carpentier Foundation) APHPGeorges PompidouEuropean Georges Pompidou Hospital Paris France
| | - Juan Grau
- Department of Epidemiology Ottawa Heart InstituteUniversity of Ottawa Ontario Canada
| | - Marc Ruel
- Department of Epidemiology Ottawa Heart InstituteUniversity of Ottawa Ontario Canada
| | - Yves Lecarpentier
- Centre de Recherche Clinique Grand Hôpital de l'Est Francilien (GHEF) Meaux France
| | - Alain Carpentier
- Biosurgical Research Lab (Carpentier Foundation) APHPGeorges PompidouEuropean Georges Pompidou Hospital Paris France.,Division of Cardiac Surgery and Research Laboratory European HospitalEuropean Georges Pompidou Hospital Paris France
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10
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Galili U. Human Natural Antibodies to Mammalian Carbohydrate Antigens as Unsung Heroes Protecting against Past, Present, and Future Viral Infections. Antibodies (Basel) 2020; 9:antib9020025. [PMID: 32580274 PMCID: PMC7344964 DOI: 10.3390/antib9020025] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 06/18/2020] [Indexed: 12/22/2022] Open
Abstract
Human natural antibodies to mammalian carbohydrate antigens (MCA) bind to carbohydrate-antigens synthesized in other mammalian species and protect against zoonotic virus infections. Three such anti-MCA antibodies are: (1) anti-Gal, also produced in Old-World monkeys and apes, binds to α-gal epitopes synthesized in non-primate mammals, lemurs, and New-World monkeys; (2) anti-Neu5Gc binds to Neu5Gc (N-glycolyl-neuraminic acid) synthesized in apes, Old-World monkeys, and many non-primate mammals; and (3) anti-Forssman binds to Forssman-antigen synthesized in various mammals. Anti-viral protection by anti-MCA antibodies is feasible because carbohydrate chains of virus envelopes are synthesized by host glycosylation machinery and thus are similar to those of their mammalian hosts. Analysis of MCA glycosyltransferase genes suggests that anti-Gal appeared in ancestral Old-World primates following catastrophic selection processes in which parental populations synthesizing α-gal epitopes were eliminated in enveloped virus epidemics. However, few mutated offspring in which the α1,3galactosyltransferase gene was accidentally inactivated produced natural anti-Gal that destroyed viruses presenting α-gal epitopes, thereby preventing extinction of mutated offspring. Similarly, few mutated hominin offspring that ceased to synthesize Neu5Gc produced anti-Neu5Gc, which destroyed viruses presenting Neu5Gc synthesized in parental hominin populations. A present-day example for few humans having mutations that prevent synthesis of a common carbohydrate antigen (produced in >99.99% of humans) is blood-group Bombay individuals with mutations inactivating H-transferase; thus, they cannot synthesize blood-group O (H-antigen) but produce anti-H antibody. Anti-MCA antibodies prevented past extinctions mediated by enveloped virus epidemics, presently protect against zoonotic-viruses, and may protect in future epidemics. Travelers to regions with endemic zoonotic viruses may benefit from vaccinations elevating protective anti-MCA antibody titers.
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Affiliation(s)
- Uri Galili
- Department of Medicine, Rush University Medical School, Chicago, IL 60605, USA
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11
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Jin C, Cherian RM, Liu J, Playà-Albinyana H, Galli C, Karlsson NG, Breimer ME, Holgersson J. Identification by mass spectrometry and immunoblotting of xenogeneic antigens in the N- and O-glycomes of porcine, bovine and equine heart tissues. Glycoconj J 2020; 37:485-498. [PMID: 32542517 PMCID: PMC7329767 DOI: 10.1007/s10719-020-09931-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 05/06/2020] [Accepted: 06/04/2020] [Indexed: 12/11/2022]
Abstract
Animal bioprosthetic heart valves (BHV) are used to replace defective valves in patients with valvular heart disease. Especially young BHV recipients may experience a structural valve deterioration caused by an immune reaction in which α-Gal and Neu5Gc are potential target antigens. The expression of these and other carbohydrate antigens in animal tissues used for production of BHV was explored. Protein lysates of porcine aortic and pulmonary valves, and porcine, bovine and equine pericardia were analyzed by Western blotting using anti-carbohydrate antibodies and lectins. N-glycans were released by PNGase F digestion and O-glycans by β-elimination. Released oligosaccharides were analyzed by liquid chromatography – tandem mass spectrometry. In total, 102 N-glycans and 40 O-glycans were identified in animal heart tissue lysates. The N- and O-glycan patterns were different between species. α-Gal and Neu5Gc were identified on both N- and O-linked glycans, N,N´-diacetyllactosamine (LacdiNAc) on N-glycans only and sulfated O-glycans. The relative amounts of α-Gal-containing N-glycans were higher in bovine compared to equine and porcine pericardia. In contrast to the restricted number of proteins carrying α-Gal and LacdiNAc, the distribution of proteins carrying Neu5Gc-determinants varied between species and between different tissues of the same species. Porcine pericardium carried the highest level of Neu5Gc-sialylated O-glycans, and bovine pericardium the highest level of Neu5Gc-sialylated N-glycans. The identified N- and O-linked glycans, some of which may be immunogenic and remain in BHVs manufactured for clinical use, could direct future genetic engineering to prevent glycan expression rendering the donor tissues less immunogenic in humans.
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Affiliation(s)
- Chunsheng Jin
- Department of Medical Biochemistry, Institute of Biomedicine Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
| | - Reeja Maria Cherian
- Department of Surgery, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - Jining Liu
- Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Heribert Playà-Albinyana
- Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Biochemistry and Biotechnology, Faculty of Chemistry, Rovira i Virgili University, Tarragona, Spain
| | - Cesare Galli
- Avantea Laboratory of Reproductive Technologies, Cremona, Italy.,Avantea Foundation, Cremona, Italy
| | - Niclas G Karlsson
- Department of Medical Biochemistry, Institute of Biomedicine Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Michael E Breimer
- Department of Surgery, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - Jan Holgersson
- Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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12
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Nanno Y, Sterner E, Gildersleeve JC, Hering BJ, Burlak C. Profiling natural serum antibodies of non-human primates with a carbohydrate antigen microarray. Xenotransplantation 2019; 27:e12567. [PMID: 31762117 DOI: 10.1111/xen.12567] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 10/07/2019] [Accepted: 10/13/2019] [Indexed: 12/28/2022]
Abstract
BACKGROUND Engineering of α-Galactosyltransferase gene-knockout pigs circumvented hyperacute rejection of pig organs after xenotransplantation in non-human primates. Overcoming this hurdle revealed the importance of non-α-Gal carbohydrate antigens in the immunobiology of acute humoral xenograft rejection. METHODS This study analyzed serum from seven naïve cynomolgus monkeys (blood type O/B/AB = 3/2/2) for the intensity of natural IgM and IgG signals using carbohydrate antigen microarray, which included historically reported α-Gal and non-α-Gal carbohydrate antigens with various modifications. RESULTS The median (range) of IgM and IgG signals were 12.71 (7.23-16.38) and 9.05 (7.23-15.90), respectively. The highest IgM and IgG signals with narrowest distribution were from mono- and disaccharides, followed by modified structures. Natural anti-α-Gal antibody signals were medium to high in IgM (11.2-15.9) and medium in IgG (8.5-11.6) spectra, and was highest with Lac core structure (Galα1-3Galβ1-4Glc, iGb3) and lowest with LacNAc core structure (Galα1-3Galβ1-4GlcNAc). Similar signal intensities (up to 15.8 in IgM and up to 11.8 in IgG) were observed for historically detected natural non-α-Gal antigens, which included Tn antigen, T antigen, GM2 glycolipid, and Sda antigen. The hierarchical clustering analysis revealed the presence of clusters of anti-A antibodies and was capable of distinguishing between the blood group B and AB non-human primates. CONCLUSIONS The results presented here provide the most comprehensive evaluation of natural antibodies present in cynomolgus monkeys.
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Affiliation(s)
- Yoshihide Nanno
- Department of Surgery, Schulze Diabetes Institute, School of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Eric Sterner
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Jeffrey C Gildersleeve
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Bernhard J Hering
- Department of Surgery, Schulze Diabetes Institute, School of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Christopher Burlak
- Department of Surgery, Schulze Diabetes Institute, School of Medicine, University of Minnesota, Minneapolis, MN, USA
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13
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Kooner AS, Yu H, Chen X. Synthesis of N-Glycolylneuraminic Acid (Neu5Gc) and Its Glycosides. Front Immunol 2019; 10:2004. [PMID: 31555264 PMCID: PMC6724515 DOI: 10.3389/fimmu.2019.02004] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 08/07/2019] [Indexed: 12/12/2022] Open
Abstract
Sialic acids constitute a family of negatively charged structurally diverse monosaccharides that are commonly presented on the termini of glycans in higher animals and some microorganisms. In addition to N-acetylneuraminic acid (Neu5Ac), N-glycolyl neuraminic acid (Neu5Gc) is among the most common sialic acid forms in nature. Nevertheless, unlike most animals, human cells loss the ability to synthesize Neu5Gc although Neu5Gc-containing glycoconjugates have been found on human cancer cells and in various human tissues due to dietary incorporation of Neu5Gc. Some pathogenic bacteria also produce Neu5Ac and the corresponding glycoconjugates but Neu5Gc-producing bacteria have yet to be found. In addition to Neu5Gc, more than 20 Neu5Gc derivatives have been found in non-human vertebrates. To explore the biological roles of Neu5Gc and its naturally occurring derivatives as well as the corresponding glycans and glycoconjugates, various chemical and enzymatic synthetic methods have been developed to obtain a vast array of glycosides containing Neu5Gc and/or its derivatives. Here we provide an overview on various synthetic methods that have been developed. Among these, the application of highly efficient one-pot multienzyme (OPME) sialylation systems in synthesizing compounds containing Neu5Gc and derivatives has been proven as a powerful strategy.
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Affiliation(s)
| | - Hai Yu
- Department of Chemistry, University of California, Davis, Davis, CA, United States
| | - Xi Chen
- Department of Chemistry, University of California, Davis, Davis, CA, United States
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14
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Li KYC. Bioprosthetic Heart Valves: Upgrading a 50-Year Old Technology. Front Cardiovasc Med 2019; 6:47. [PMID: 31032263 PMCID: PMC6470412 DOI: 10.3389/fcvm.2019.00047] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 03/26/2019] [Indexed: 01/09/2023] Open
Abstract
Prosthetic heart valves have been commonly used to address the increasing prevalence of valvular heart disease. The ideal prosthetic heart valve substitute should closely mimic the characteristics of a normal native heart valve. Despite the development of various interventions, an exemplary valve replacement does not exist. This review provides an overview of the novel engineering valve designs and explores emergent immunologic insights into age-dependent structural valve degeneration (SVD).
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Affiliation(s)
- Kan Yan Chloe Li
- Institute of Cardiovascular Science, University College London, London, United Kingdom
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15
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Schussler O, Lila N, Perneger T, Mootoosamy P, Grau J, Francois A, Smadja DM, Lecarpentier Y, Ruel M, Carpentier A. Recipients with blood group A associated with longer survival rates in cardiac valvular bioprostheses. EBioMedicine 2019; 42:54-63. [PMID: 30878598 PMCID: PMC6491382 DOI: 10.1016/j.ebiom.2019.02.047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 02/12/2019] [Accepted: 02/20/2019] [Indexed: 01/02/2023] Open
Abstract
Background Pigs/bovines share with humans some of the antigens present on cardiac valves. Two such antigens are: the major xenogenic Ag, “Gal” present in all pig/bovine very close to human B-antigen of ABO-blood-group system; the minor Ag, pig histo-blood-group AH-antigen identical to human AH-antigen and present by some animals. We hypothesize that these antigens may modify the immunogenicity of the bioprosthesis and also its longevity. ABO distribution may vary between patients with low (<6 years) and high (≥15 years) bioprostheses longevity. Methods Single-centre registry study (Paris, France) including all degenerative porcine bioprostheses (mostly Carpentier-Edwards 2nd/3rd generation heart valves) explanted between 1985 and 1998 and some bovine bioprostheses. For period 1998–2014, all porcine bioprostheses with longevity ≥13 years (follow-up ≥29 years). Important predictive factors for bioprosthesis longevity: number, site of implantation, age were collected. Blood group and other variables were entered into an ordinal logistic regression analysis model predicting valve longevity, categorized as low (<6 years), medium (6–14.9 years), and high (≥15 years). Findings Longevity and ABO-blood group were obtained for 483 explanted porcine bioprostheses. Mean longevity was 10.2 ± 3.9 years [0–28] and significantly higher for A-patients than others (P = 0.009). Using multivariate analysis, group A was a strong predictive factor of longevity (OR 2.09; P < 0.001). For the 64 explanted bovine bioprosthesis with low/medium longevity, the association, with A-group was even more significant. Interpretation Patients of A-group but not B have a higher longevity of their bioprostheses. Future graft-host phenotyping and matching may give rise to a new generation of long-lasting bioprosthesis for implantation in humans, especially for the younger population. Fund None.
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Affiliation(s)
- O Schussler
- Division of Cardiovascular Surgery and Cardiovascular Research Laboratory, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland.
| | - N Lila
- Laboratory of Biosurgical Research (Alain Carpentier Foundation), University Paris Descartes, Sorbonne Paris Cité, Paris F-75475, France
| | - T Perneger
- Department of Clinical Epidemiology, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland
| | - P Mootoosamy
- Division of Cardiovascular Surgery and Cardiovascular Research Laboratory, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland
| | - J Grau
- Division of Cardiac Surgery and Research Laboratory, Department of Epidemiology, Ottawa Heart Institute, University of Ottawa Heart, Ottawa, Ontario, Canada
| | - A Francois
- Etablissement Français du Sang (EFS), Ile de France, Immuno-hematology Laboratory, Georges Pompidou Hospital, Paris, France
| | - D M Smadja
- Division of Cardiovascular Surgery and Cardiovascular Research Laboratory, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland; AP-HP, Hôpital Européen Georges Pompidou, Hematology Department, Paris Descartes University, Sorbonne Paris Cite, Inserm UMR-S1140, Paris, France
| | - Y Lecarpentier
- Centre de Recherche Clinique, Grand Hôpital de l'Est Francilien (GHEF), Meaux, France
| | - M Ruel
- Division of Cardiac Surgery and Research Laboratory, Department of Epidemiology, Ottawa Heart Institute, University of Ottawa Heart, Ottawa, Ontario, Canada
| | - A Carpentier
- Laboratory of Biosurgical Research (Alain Carpentier Foundation), University Paris Descartes, Sorbonne Paris Cité, Paris F-75475, France; AP-HP, Hôpital Européen Georges Pompidou, Department of Cardiovascular Surgery, Paris, France
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16
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Li Q, Shaikh S, Iwase H, Long C, Lee W, Zhang Z, Wang Y, Ayares D, Cooper DKC, Hara H. Carbohydrate antigen expression and anti-pig antibodies in New World capuchin monkeys: Relevance to studies of xenotransplantation. Xenotransplantation 2019; 26:e12498. [PMID: 30770572 DOI: 10.1111/xen.12498] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 11/23/2018] [Accepted: 12/06/2018] [Indexed: 02/06/2023]
Abstract
BACKGROUND Old World non-human primates (OWNHPs) are used for preclinical pig-to-NHP studies. However, like pigs, OWNHPs express Neu5Gc, and therefore do not develop natural anti-Neu5Gc antibodies. New World NHPs (NWNHPs) have been reported not to express Neu5Gc. We investigated the potential of NWNHPs in xenotransplantation research. METHODS We investigated expression of Gal, Neu5Gc, and Sda antigens on RBCs and PBMCs from humans, selected OWNHPs, and capuchin monkeys (a NWNHP). Serum anti-Gal and anti-Neu5Gc IgM and IgG levels were measured by ELISA. Binding of primate serum IgM and IgG to pig RBCs was measured by flow cytometry. RESULTS (a) Neither humans, OWNHPs, or capuchin monkeys expressed Gal on their RBCs, but capuchins expressed Gal on PBMCs. Humans and capuchins did not express Neu5Gc on either RBCs or PBMCs, but OWNHPs expressed Neu5Gc on both cells. Sda was not expressed on any RBCs or PBMCs. (b) By ELISA, human and OWNHP, but not capuchin, sera showed IgM and IgG binding to Gal. Human and capuchin, but not OWNHP, sera demonstrated some binding to Neu5Gc. (c) Anti-Sda IgM/IgG antibodies were detected in OWNHP sera. Knockout of Sda on pig RBCs did not significantly reduce human and capuchin antibody binding. CONCLUSION Capuchin monkeys could be surrogates for humans in experiments using RBCs, islets, neuronal cells, etc, from triple-knockout pigs (but may be too small to be used as recipients of pig organ grafts).
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Affiliation(s)
- Qi Li
- Department of Surgery, Xenotransplantation Program, University of Alabama at Birmingham, Birmingham, Alabama.,Second Affiliated Hospital, University of South China, Hengyang City, China
| | - Sahar Shaikh
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Hayato Iwase
- Department of Surgery, Xenotransplantation Program, University of Alabama at Birmingham, Birmingham, Alabama.,Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Cassandra Long
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Whayoung Lee
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Zhongqiang Zhang
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, Pennsylvania.,Department of Organ Transplantation and General Surgery, Second Xiangya Hospital of Central South University, Changsha, China
| | - Yi Wang
- Second Affiliated Hospital, University of South China, Hengyang City, China.,Transplantation Institute of Hainan Medical University, Haikou, China
| | | | - David K C Cooper
- Department of Surgery, Xenotransplantation Program, University of Alabama at Birmingham, Birmingham, Alabama.,Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Hidetaka Hara
- Department of Surgery, Xenotransplantation Program, University of Alabama at Birmingham, Birmingham, Alabama.,Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
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17
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Immune Responses of HLA Highly Sensitized and Nonsensitized Patients to Genetically Engineered Pig Cells. Transplantation 2019; 102:e195-e204. [PMID: 29266033 DOI: 10.1097/tp.0000000000002060] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND We investigated in vitro whether HLA highly sensitized patients with end-stage renal disease will be disadvantaged immunologically after a genetically engineered pig kidney transplant. METHODS Blood was drawn from patients with a calculated panel-reactive antibody (cPRA) 99% to 100% (Gp1, n = 10) or cPRA 0% (Gp2, n = 12), and from healthy volunteers (Gp3, n = 10). Serum IgM and IgG binding was measured (i) to galactose-α1-3 galactose and N-glycolylneuraminic acid glycans by enzyme-linked immunosorbent assay, and (ii) to pig red blood cell, pig aortic endothelial cells, and pig peripheral blood mononuclear cell from α1,3-galactosyltransferase gene-knockout (GTKO)/CD46 and GTKO/CD46/cytidine monophosphate-N-acetylneuraminic acid hydroxylase-knockout (CMAHKO) pigs by flow cytometry. (iii) T-cell and B-cell phenotypes were determined by flow cytometry, and (iv) proliferation of T-cell and B-cell carboxyfluorescein diacetate succinimidyl ester-mixed lymphocyte reaction. RESULTS (i) By enzyme-linked immunosorbent assay, there was no difference in IgM or IgG binding to galactose-α1-3 galactose or N-glycolylneuraminic acid between Gps1 and 2, but binding was significantly reduced in both groups compared to Gp3. (ii) IgM and IgG binding in Gps1 and 2 was also significantly lower to GTKO/CD46 pig cells than in healthy controls, but there were no differences between the 3 groups in binding to GTKO/CD46/CMAHKO cells. (iii and iv) Gp1 patients had more memory T cells than Gp2, but there was no difference in T or B cell proliferation when stimulated by any pig cells. The proliferative responses in all 3 groups were weakest when stimulated by GTKO/CD46/CMAHKO pig peripheral blood mononuclear cell. CONCLUSIONS (i) End-stage renal disease was associated with low antipig antibody levels. (ii) Xenoreactivity decreased with increased genetic engineering of pig cells. (iii) High cPRA status had no significant effect on antibody binding or T-cell and B-cell response.
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18
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Stahl EC, Bonvillain RW, Skillen CD, Burger BL, Hara H, Lee W, Trygg CB, Didier PJ, Grasperge BF, Pashos NC, Bunnell BA, Bianchi J, Ayares DL, Guthrie KI, Brown BN, Petersen TH. Evaluation of the host immune response to decellularized lung scaffolds derived from α-Gal knockout pigs in a non-human primate model. Biomaterials 2018; 187:93-104. [DOI: 10.1016/j.biomaterials.2018.09.038] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 09/21/2018] [Accepted: 09/23/2018] [Indexed: 12/11/2022]
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Costa A, Naranjo JD, Londono R, Badylak SF. Biologic Scaffolds. Cold Spring Harb Perspect Med 2017; 7:cshperspect.a025676. [PMID: 28320826 DOI: 10.1101/cshperspect.a025676] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Biologic scaffold materials composed of allogeneic or xenogeneic extracellular matrix are commonly used for the repair and functional reconstruction of injured and missing tissues. These naturally occurring bioscaffolds are manufactured by the removal of the cellular content from source tissues while preserving the structural and functional molecular units of the remaining extracellular matrix (ECM). The mechanisms by which these bioscaffolds facilitate constructive remodeling and favorable clinical outcomes include release or creation of effector molecules that recruit endogenous stem/progenitor cells to the site of scaffold placement and modulation of the innate immune response, specifically the activation of an anti-inflammatory macrophage phenotype. The methods by which ECM biologic scaffolds are prepared, the current understanding of in vivo scaffold remodeling, and the associated clinical outcomes are discussed in this article.
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Affiliation(s)
- Alessandra Costa
- McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania 15219
| | - Juan Diego Naranjo
- McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania 15219
| | - Ricardo Londono
- McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania 15219.,School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15219
| | - Stephen F Badylak
- McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania 15219.,Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15219.,Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15219
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20
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Gao B, Long C, Lee W, Zhang Z, Gao X, Landsittel D, Ezzelarab M, Ayares D, Huang Y, Cooper DKC, Wang Y, Hara H. Anti-Neu5Gc and anti-non-Neu5Gc antibodies in healthy humans. PLoS One 2017; 12:e0180768. [PMID: 28715486 PMCID: PMC5513429 DOI: 10.1371/journal.pone.0180768] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Accepted: 06/21/2017] [Indexed: 02/03/2023] Open
Abstract
Our group previously investigated the levels of anti-Gal and anti-nonGal IgM and IgG in a cohort of 75 healthy humans of various backgrounds, and found some significant differences related to factors such as age, gender, ABO blood group, diet, vaccination history, and geographic location during childhood. We have now expanded our cohort (n = 84) to investigate the levels of anti-Neu5Gc and anti-nonGal/nonNeu5Gc antibodies in healthy humans. Anti-nonGal and anti-nonGal/nonNeu5Gc human IgM and IgG binding to pRBCs and pAECs from GTKO/CD46 and GTKO/CD46/Neu5GcKO pigs were measured by flow cytometry. Anti-Gal and anti-Neu5Gc IgM and IgG levels were measured by ELISA. In summary, (i) the great majority (almost 100%) of humans had anti-Neu5Gc IgM and IgG antibodies that bound to pAECs and approximately 50% had anti-Neu5Gc antibodies that bound to pRBCs, (ii) there was significantly less human antibody binding to pig cells that did not express either Gal or Neu5Gc compared with those that did not express Gal alone, (iii) the levels of both IgM and IgG binding to GTKO/CD46/Neu5GcKO pRBCs and pAECs were low, (iv) the level of anti-Neu5Gc IgG was higher in men than women, (v) the level did not change with age or diet, and there was some variability associated with (vi) previous vaccination history and (vii) the geographic region in which the individual spent his or her childhood. Our study confirms that human antibody binding to RBCs and AECs from GTKO/CD46/Neu5GcKO pigs is greatly reduced compared to binding to GTKO/CD46 cells. However, all humans appear to have a low level of antibody that binds to pAECs that is not directed to either Gal or Neu5Gc. Our findings require consideration in planning clinical trials of xenotransplantation.
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Affiliation(s)
- Bingsi Gao
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, United States of America
- Center for Kidney Transplantation, Second Affiliated Hospital of the University of South China, Hengyang, Hunan, China
- Department of Obstetrics and Gynecology, Second Affiliated Hospital of the University of South China, Hengyang, Hunan, China
| | - Cassandra Long
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Whayoung Lee
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Zhongqiang Zhang
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, United States of America
- Department of General Surgery, Second Xiangya Hospital of the Central South University, Changsha, Hunan, China
| | - Xiaotian Gao
- Department of Biostatistics, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Doug Landsittel
- Department of Biostatistics and Clinical and Translational Science, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Mohamed Ezzelarab
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - David Ayares
- Revivicor, Blacksburg, VA, United States of America
| | - Yuliang Huang
- Department of Obstetrics and Gynecology, Second Affiliated Hospital of the University of South China, Hengyang, Hunan, China
| | - David K. C. Cooper
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Yi Wang
- Center for Kidney Transplantation, Second Affiliated Hospital of the University of South China, Hengyang, Hunan, China
- * E-mail: (HH); (YW)
| | - Hidetaka Hara
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, United States of America
- * E-mail: (HH); (YW)
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21
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Cowan PJ, Ierino FL. Reducing the Threshold for Clinical Renal Xenotransplantation. Transplantation 2017; 101:692-693. [PMID: 28099406 PMCID: PMC7228590 DOI: 10.1097/tp.0000000000001641] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 01/06/2017] [Indexed: 11/26/2022]
Affiliation(s)
- Peter J Cowan
- 1 Immunology Research Centre, St Vincent's Hospital Melbourne, Victoria, Australia. 2 Department of Medicine, University of Melbourne, St Vincent's Hospital Melbourne, Victoria, Australia. 3 Department of Nephrology, St Vincent's Hospital Melbourne, Victoria, Australia
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22
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Hurh S, Kang B, Choi I, Cho B, Lee EM, Kim H, Kim YJ, Chung YS, Jeong JC, Hwang JI, Kim JY, Lee BC, Surh CD, Yang J, Ahn C. Human antibody reactivity against xenogeneic N-glycolylneuraminic acid and galactose-α-1,3-galactose antigen. Xenotransplantation 2016; 23:279-92. [PMID: 27373998 DOI: 10.1111/xen.12239] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 05/07/2016] [Indexed: 12/19/2022]
Abstract
BACKGROUND Despite the development of α1,3-galactosyl transferase-knockout (GTKO) pigs, acute humoral xenograft rejection caused by antibodies against non-Gal antigens, along with complement activation, are hurdles that need to be overcome. Among non-Gal antigens, N-glycolylneuraminic acid (Neu5Gc) is considered to play an important role in xenograft rejection in human. METHODS We generated human embryonic kidney 293 (HEK293) cells that expressed xenogeneic Neu5Gc (HEK293-pCMAH) or α1,3Gal (HEK293-pGT) antigen and investigated the degree of human antibody binding and complement-dependent cytotoxicity (CDC) against these antigens using 100 individual human sera. RESULTS Both IgM and IgG bound to α1,3Gal, while only IgG bound to Neu5Gc. Of the ABO blood groups, the degree of IgG binding to α1,3Gal was highest for blood group A. The degree of CDC against HEK293-pCMAH cells was significantly lower than that against HEK293-pGT cells. However, CDC against HEK293-pCMAH cells was significantly higher than that against control HEK293 cells. In addition, the severity of CDC against HEK293-pCMAH cells positively correlated with that against GTKO pig aortic endothelial cells (PAECs), suggesting that Neu5Gc is the main antigen in GTKO PAECs. Similar to antibody-binding activity, only IgG binding correlated with CDC against HEK293-pCMAH cells. The most common subclass of IgGs against Neu5Gc was IgG1, which typically induces strong complement activation. CONCLUSIONS We showed that IgG-mediated CDC was detected in Neu5Gc-overexpressed HEK293 cells incubated with human sera; however, this antibody reactivity to Neu5Gc was highly variable among individuals. Our results suggest that additional modifications to the CMAH gene should be considered for widespread use of pig organs for human transplants.
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Affiliation(s)
- Sunghoon Hurh
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Korea.,Graduate School of Translational Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Bohae Kang
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Korea.,Graduate School of Translational Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Inho Choi
- Department of Pharmaceutical Engineering, College of Life and Health Sciences, Hoseo University, Asan, Chungcheongnam-do, Korea
| | - Bumrae Cho
- Designed Animal & Transplantation Research Institute, Institute of Green Bio Science & Technology, Seoul National University, Pyeongchang, Gangwon-do, Korea
| | - Eun Mi Lee
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Korea.,Graduate School of Translational Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Hwajung Kim
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | - Young June Kim
- Designed Animal & Transplantation Research Institute, Institute of Green Bio Science & Technology, Seoul National University, Pyeongchang, Gangwon-do, Korea
| | - Yun Shin Chung
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | - Jong Cheol Jeong
- Department of Nephrology, Ajou University School of Medicine, Suwon, Gyeonggi-do, Korea
| | - Jong-Ik Hwang
- Graduate School of Medicine, Korea University, Seoul, Korea
| | - Jae Young Kim
- Department of Life Science, Gachon University, Seongnam, Korea
| | - Byeong Chun Lee
- Designed Animal & Transplantation Research Institute, Institute of Green Bio Science & Technology, Seoul National University, Pyeongchang, Gangwon-do, Korea.,Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, Seoul, Korea.,Research Institute for Veterinary Science, Seoul National University, Seoul, Korea
| | - Charles D Surh
- Academy of Immunology and Microbiology, Institute for Basic Science, Pohang, Korea.,Department of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, Korea.,Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology, La Jolla, CA, USA
| | - Jaeseok Yang
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Korea.,Transplantation Center, Seoul National University Hospital, Seoul, Korea
| | - Curie Ahn
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Korea.,Designed Animal & Transplantation Research Institute, Institute of Green Bio Science & Technology, Seoul National University, Pyeongchang, Gangwon-do, Korea.,Transplantation Center, Seoul National University Hospital, Seoul, Korea.,Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
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23
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Abstract
The availability of cells, tissues and organs from a non-human species such as the pig could, at least in theory, meet the demand of organs necessary for clinical transplantation. At this stage, the important goal of getting over the first year of survival has been reported for both cellular and solid organ xenotransplantation in relevant preclinical primate models. In addition, xenotransplantation is already in the clinic as shown by the broad use of animal-derived medical devices, such as bioprosthetic heart valves and biological materials used for surgical tissue repair. At this stage, however, prior to starting a wide-scale clinical application of xenotransplantation of viable cells and organs, the important obstacle represented by the humoral immune response will need to be overcome. Likewise, the barriers posed by the activation of the innate immune system and coagulative pathway will have to be controlled. As far as xenogeneic nonviable xenografts, increasing evidence suggests that considerable immune reactions, mediated by both innate and adaptive immunity, take place and influence the long-term outcome of xenogeneic materials in patients, possibly precluding the use of bioprosthetic heart valves in young individuals. In this context, the present article provides an overview of current knowledge on the immune processes following xenotransplantation and on the possible therapeutic interventions to overcome the immunological drawbacks involved in xenotransplantation.
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Affiliation(s)
- M Vadori
- CORIT (Consortium for Research in Organ Transplantation), Via dell'Università 10, 35020 Legnaro, Padua, Italy
| | - E Cozzi
- CORIT (Consortium for Research in Organ Transplantation), Via dell'Università 10, 35020 Legnaro, Padua, Italy.,Transplant Immunology Unit, Department of Transfusion Medicine, Padua University Hospital, Via Giustiniani, 2, 35128 Padua, Italy
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24
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Lee W, Hara H, Ezzelarab MB, Iwase H, Bottino R, Long C, Ramsoondar J, Ayares D, Cooper DKC. Initial in vitro studies on tissues and cells from GTKO/CD46/NeuGcKO pigs. Xenotransplantation 2016; 23:137-50. [PMID: 26988899 DOI: 10.1111/xen.12229] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 02/15/2016] [Indexed: 12/20/2022]
Abstract
BACKGROUND The impact that the absence of expression of NeuGc in pigs might have on pig organ or cell transplantation in humans has been studied in vitro, but only using red blood cells (pRBCs) and peripheral blood mononuclear cells (pPBMCs) as the target cells for immune assays. We have extended this work in various in vitro models and now report our initial results. METHODS The models we have used involve GTKO/hCD46 and GTKO/hCD46/NeuGcKO pig aortas and corneas, and pRBCs, pPBMCs, aortic endothelial cells (pAECs), corneal endothelial cells (pCECs), and isolated pancreatic islets. We have investigated the effect of the absence of NeuGc expression on (i) human IgM and IgG binding, (ii) the T-cell proliferative response, (iii) human platelet aggregation, and (iv) in an in vitro assay of the instant blood-mediated inflammatory reaction (IBMIR) following exposure of pig islets to human blood/serum. RESULTS The lack of expression of NeuGc on some pig tissues (aortas, corneas) and cells (RBCs, PBMCs, AECs) significantly reduces the extent of human antibody binding. In contrast, the absence of NeuGc expression on some pig tissues (CECs, isolated islet cells) does not reduce human antibody binding, possibly due to their relatively low NeuGc expression level. The strength of the human T-cell proliferative response may also be marginally reduced, but is already weak to GTKO/hCD46 pAECs and islet cells. We also demonstrate that the absence of NeuGc expression on GTKO/hCD46 pAECs does not reduce human platelet aggregation, and nor does it significantly modify the IBMIR to pig islets. CONCLUSION The absence of NeuGc on some solid organs from GTKO/hCD46/NeuGcKO pigs should reduce the human antibody response after clinical transplantation when compared to GTKO/hCD46 pig organs. However, the clinical benefit of using certain tissue (e.g., cornea, islets) from GTKO/hCD46/NeuGcKO pigs is questionable.
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Affiliation(s)
- Whayoung Lee
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Hidetaka Hara
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Mohamed B Ezzelarab
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Hayato Iwase
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Rita Bottino
- Institute of Cellular Therapeutics, Allegheny-Singer Research Institute, Pittsburgh, PA, USA
| | - Cassandra Long
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | | | | | - David K C Cooper
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
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25
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Cooper DKC. Modifying the sugar icing on the transplantation cake. Glycobiology 2016; 26:571-81. [PMID: 26935763 DOI: 10.1093/glycob/cww028] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 02/25/2016] [Indexed: 12/13/2022] Open
Abstract
As a transplant surgeon, my interest in glycobiology began through my research into ABO-incompatible allotransplantation, and grew when my goal became overcoming the shortage of organs from deceased human donors by the transplantation of pig organs into patients with terminal organ failure (xenotransplantation/cross-species transplantation). The major target for human "natural" (preformed) anti-pig antibodies is galactose-α(1,3)-galactose (the "Gal" epitope), which is expressed on many pig cells, including the vascular endothelium. The binding of human IgM and IgG antibodies to Gal antigens initiates the process of hyperacute rejection, resulting in destruction of the pig graft within minutes or hours. This major barrier has been overcome by the production of pigs in which the gene for the enzyme α(1,3)-galactosyltransferase (GT) has been deleted by genetic engineering, resulting in GT knockout (GTKO) pigs. The two other known carbohydrate antigenic targets on pig cells for human anti-pig antibodies are (i) the product of the cytidine monophosphate-N-acetylneuraminic acid hydroxylase (CMAH) gene, i.e., N-glycolylneuraminic acid, and (ii) the product of the β1,4 N-acetylgalactosaminyltransferase gene, i.e., the Sd(a) antigen. Expression of these two has also been deleted in pigs. These genetic manipulations, together with others directed to overcoming primate complement and coagulation activation (the latter of which also relates to glycobiology) have contributed to the prolongation of pig graft survival in nonhuman primate recipients to many months rather than a few minutes. Clinical trials of the transplantation of pig cells are already underway and transplantation of pig organs may be expected within the relatively near future.
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Affiliation(s)
- David K C Cooper
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
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26
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Cooper DKC, Ezzelarab MB, Hara H, Iwase H, Lee W, Wijkstrom M, Bottino R. The pathobiology of pig-to-primate xenotransplantation: a historical review. Xenotransplantation 2016; 23:83-105. [PMID: 26813438 DOI: 10.1111/xen.12219] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 12/22/2015] [Indexed: 12/16/2022]
Abstract
The immunologic barriers to successful xenotransplantation are related to the presence of natural anti-pig antibodies in humans and non-human primates that bind to antigens expressed on the transplanted pig organ (the most important of which is galactose-α1,3-galactose [Gal]), and activate the complement cascade, which results in rapid destruction of the graft, a process known as hyperacute rejection. High levels of elicited anti-pig IgG may develop if the adaptive immune response is not prevented by adequate immunosuppressive therapy, resulting in activation and injury of the vascular endothelium. The transplantation of organs and cells from pigs that do not express the important Gal antigen (α1,3-galactosyltransferase gene-knockout [GTKO] pigs) and express one or more human complement-regulatory proteins (hCRP, e.g., CD46, CD55), when combined with an effective costimulation blockade-based immunosuppressive regimen, prevents early antibody-mediated and cellular rejection. However, low levels of anti-non-Gal antibody and innate immune cells and/or platelets may initiate the development of a thrombotic microangiopathy in the graft that may be associated with a consumptive coagulopathy in the recipient. This pathogenic process is accentuated by the dysregulation of the coagulation-anticoagulation systems between pigs and primates. The expression in GTKO/hCRP pigs of a human coagulation-regulatory protein, for example, thrombomodulin, is increasingly being associated with prolonged pig graft survival in non-human primates. Initial clinical trials of islet and corneal xenotransplantation are already underway, and trials of pig kidney or heart transplantation are anticipated within the next few years.
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Affiliation(s)
- David K C Cooper
- The Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Mohamed B Ezzelarab
- The Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Hidetaka Hara
- The Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Hayato Iwase
- The Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Whayoung Lee
- The Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Martin Wijkstrom
- The Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Rita Bottino
- Institute for Cellular Therapeutics, Allegheny-Singer Research Institute, Pittsburgh, PA, USA
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27
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Kim MK, Hara H. Current status of corneal xenotransplantation. Int J Surg 2015; 23:255-260. [DOI: 10.1016/j.ijsu.2015.07.685] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 07/15/2015] [Accepted: 07/17/2015] [Indexed: 02/09/2023]
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28
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Byrne GW, McGregor CGA, Breimer ME. Recent investigations into pig antigen and anti-pig antibody expression. Int J Surg 2015; 23:223-228. [PMID: 26306769 DOI: 10.1016/j.ijsu.2015.07.724] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 07/22/2015] [Accepted: 07/26/2015] [Indexed: 01/17/2023]
Abstract
Genetic engineering of donor pigs to eliminate expression of the dominant xenogeneic antigen galactose α1,3 galactose (Gal) has created a sea change in the immunobiology of xenograft rejection. Antibody mediated xenograft rejection of GGTA-1 α-galactosyltransferase (GTKO) deficient organs is now directed to a combination of non-Gal pig protein and carbohydrate antigens. Glycan analysis of GTKO tissues identified no new neo-antigens but detected high levels of N-acetylneuraminic acid (Neu5Gc) modified glycoproteins and glycolipids. Humans produce anti-Neu5Gc antibody and in very limited clinical studies sometimes show an induced anti-Neu5Gc antibody response after challenge with pig tissue. The pathogenicity of anti-Neu5Gc antibody in xenotransplantation is not clear however as non-human transplant models, critical for modelling anti-Gal immunity, do not produce anti-Neu5Gc antibody. Antibody induced after xenotransplantation in non-human primates is directed to an array of pig endothelial cells proteins and to a glycan produced by the pig B4GALNT2 gene. We anticipate that immune suppression will significantly affect the T-cell dependent and independent specificity of an induced antibody response and that donor pigs deficient in synthesis of multiple xenogeneic glycans will be important to future studies.
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Affiliation(s)
- Guerard W Byrne
- Department of Surgery, Mayo Clinic, Rochester, MN 55905, USA; Institute of Cardiovascular Science, University College London, London WC1E 6JF, UK.
| | - Christopher G A McGregor
- Department of Surgery, Mayo Clinic, Rochester, MN 55905, USA; Institute of Cardiovascular Science, University College London, London WC1E 6JF, UK
| | - Michael E Breimer
- Department of Surgery, Institute of Clinical Sciences, Sahlgrenska Academy at Gothenburg University, Gothenburg, Sweden
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29
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Galili U. Avoiding Detrimental Human Immune Response Against Mammalian Extracellular Matrix Implants. TISSUE ENGINEERING PART B-REVIEWS 2015; 21:231-41. [DOI: 10.1089/ten.teb.2014.0392] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Uri Galili
- Department of Surgery, University of Massachusetts Medical School, Worcester, Massachusetts
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30
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Byrne GW, Du Z, Stalboerger P, Kogelberg H, McGregor CGA. Cloning and expression of porcine β1,4 N-acetylgalactosaminyl transferase encoding a new xenoreactive antigen. Xenotransplantation 2014; 21:543-54. [PMID: 25176027 PMCID: PMC4262693 DOI: 10.1111/xen.12124] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 05/28/2014] [Indexed: 01/03/2023]
Abstract
Background Xenograft rejection of pigs organs with an engineered mutation in the GGTA-1 gene (GTKO) remains a predominantly antibody mediated process which is directed to a variety of non-Gal protein and carbohydrate antigens. We previously used an expression library screening strategy to identify six porcine endothelial cell cDNAs which encode pig antigens that bind to IgG induced after pig-to-primate cardiac xenotransplantation. One of these gene products was a glycosyltransferase with homology to the bovine β1,4 N-acetylgalactosaminyltransferase (B4GALNT2). We now characterize the porcine B4GALNT2 gene sequence, genomic organization, expression, and functional significance. Methods The porcine B4GALNT2 cDNA was recovered from the original library isolate, subcloned, sequenced, and used to identify a bacterial artificial chromosome (BAC) containing the entire B4GALNT2 locus from the Children's Hospital Oakland Research Institute BACPAC Resource Centre (#AC173453). PCR primers were designed to map the intron/exon genomic organization in the BAC clone. A stable human embryonic kidney (HEK) cell line expressing porcine B4GALNT2 (HEK-B4T) was produced. Expression of porcine B4GALNT2 in HEK-B4T cells was characterized by immune staining and siRNA transfection. The effects of B4GALNT2 expression in HEK-B4T cells was measured by flow cytometry and complement mediated lysis. Antibody binding to HEK and HEK-B4T cells was used to detect an induced antibody response to the B4GALNT2 produced glycan and the results were compared to GTKO PAEC specific non-Gal antibody induction. Expression of porcine B4GALNT2 in pig cells and tissues was measured by qualitative and quantitative real time reverse transcriptase PCR and by Dolichos biflorus agglutinin (DBA) tissue staining. Results The porcine B4GALNT2 gene shares a conserved genomic organization and encodes an open reading frame with 76 and 70% amino acid identity to the human and murine B4GALNT2 genes, respectively. The B4GALNT2 gene is expressed in porcine endothelial cells and shows a broadly distributed expression pattern. Expression of porcine B4GALNT2 in human HEK cells (HEK-B4T) results in increased binding of antibody to the B4GALNT2 enzyme, and increased reactivity with anti-Sda and DBA. HEK-B4T cells show increased sensitivity to complement mediated lysis when challenged with serum from primates after pig to primate cardiac xenotransplantation. In GTKO and GTKO:CD55 cardiac xenotransplantation recipients there is a significant correlation between the induction of a non-Gal antibody, measured using GTKO PAECs, and the induction of antibodies which preferentially bind to HEK-B4T cells. Conclusion The functional isolation of the porcine B4GALNT2 gene from a PAEC expression library, the pattern of B4GALNT2 gene expression and its sensitization of HEK-B4T cells to antibody binding and complement mediated lysis indicates that the enzymatic activity of porcine B4GALNT2 produces a new immunogenic non-Gal glycan which contributes in part to the non-Gal immune response detected after pig-to-baboon cardiac xenotransplantation.
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Affiliation(s)
- Guerard W Byrne
- Department of Surgery, Mayo Clinic, Rochester, MN, USA; Institute of Cardiovascular Science, University College London, London, UK
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31
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Abstract
PURPOSE The aim of this study was to investigate the distribution of antigens other than galactose-α-1,3-galactose (Gal) (non-Gal) recognized by human and rhesus monkey serum antibodies in the α-1,3-galactosyltransferase gene-knockout (GTKO) pig cornea. METHODS The distribution of non-Gal, specifically N-glycolylneuraminic acid (NeuGc), in the corneas from wild-type (WT) and GTKO pigs was identified. Corneal sections from WT and GTKO pigs were incubated with human or rhesus monkey serum to determine immunoglobulin (Ig)M and IgG binding to corneal tissue by means of fluorescent microscopy. RESULTS Strong expression of NeuGc was found in all layers of both WT and GTKO pig corneas. In both humans and monkeys, antibody binding (IgG > IgM) to GTKO was found to be weaker than that to entire WT pig corneas, but in both, most antibody binding, especially IgG, was to the epithelium. There was weak diffuse antibody binding, especially of IgG, to the corneal stroma, suggesting binding to antigens expressed on collagen. There was no or minimal binding of IgM/IgG to the corneal endothelium. CONCLUSIONS Although the cornea is avascular, antibodies in primate serum can bind to pig antigens, especially on epithelial cells and stromal collagen. Although the binding to entire GTKO corneas was weaker than that to WT corneas, deletion of the expression of NeuGc and expression of human complement-regulatory proteins in the pig cornea will be important if prolonged clinical corneal xenograft survival is to be achieved.
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32
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Wong ML, Griffiths LG. Immunogenicity in xenogeneic scaffold generation: antigen removal vs. decellularization. Acta Biomater 2014; 10:1806-16. [PMID: 24486910 DOI: 10.1016/j.actbio.2014.01.028] [Citation(s) in RCA: 167] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Revised: 12/15/2013] [Accepted: 01/23/2014] [Indexed: 12/11/2022]
Abstract
Decades of research have been undertaken towards the goal of tissue engineering using xenogeneic scaffolds. The primary advantages associated with use of xenogeneic tissue-derived scaffolds for in vitro development of replacement tissues and organs stem from the inherent extracellular matrix (ECM) composition and architecture. Native ECM possesses appropriate mechanical properties for physiological function of the biomaterial and signals for cell binding, growth and differentiation. Additionally, xenogeneic tissue is readily available. However, translation of xenogeneic scaffold-derived engineered tissues or organs into clinical therapies requires xenoantigenicity of the material to be adequately addressed prior to implantation. Failure to achieve this goal will result in a graft-specific host immune rejection response, jeopardizing in vivo survival of the resultant scaffold, tissue or organ. This review explores (i) the appropriateness of scaffold acellularity as an outcome measure for assessing reduction of the immunological barriers to the use of xenogeneic scaffolds for tissue engineering applications and (ii) the need for tissue engineers to strive for antigen removal during xenogeneic scaffold generation.
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Affiliation(s)
- Maelene L Wong
- Department of Veterinary Medicine: Medicine and Epidemiology, University of California, Davis, One Shields Ave., Davis, CA 95616, USA; Department of Biomedical Engineering, University of California, Davis, One Shields Ave., Davis, CA 95616, USA
| | - Leigh G Griffiths
- Department of Veterinary Medicine: Medicine and Epidemiology, University of California, Davis, One Shields Ave., Davis, CA 95616, USA.
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33
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Vadori M, Cozzi E. Immunological challenges and therapies in xenotransplantation. Cold Spring Harb Perspect Med 2014; 4:a015578. [PMID: 24616201 DOI: 10.1101/cshperspect.a015578] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Xenotransplantation, or the transplantation of cells, tissues, or organs between different species, was proposed a long time ago as a possible solution to the worldwide shortage of human organs and tissues for transplantation. In this setting, the pig is currently seen as the most likely candidate species. In the last decade, progress in this field has been remarkable and includes a better insight into the immunological mechanisms underlying the rejection process. Several immunological hurdles nonetheless remain, such as the strong antibody-mediated and innate or adaptive cellular immune responses linked to coagulation derangements, precluding indefinite xenograft survival. This article reviews our current understanding of the immunological mechanisms involved in xenograft rejection and the potential strategies that may enable xenotransplantation to become a clinical reality in the not-too-distant future.
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Affiliation(s)
- Marta Vadori
- CORIT (Consortium for Research in Organ Transplantation), Legnaro, 35020 Padua, Italy
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34
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Cowan PJ, Cooper DKC, d'Apice AJF. Kidney xenotransplantation. Kidney Int 2014; 85:265-75. [PMID: 24088952 PMCID: PMC3946635 DOI: 10.1038/ki.2013.381] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 07/12/2013] [Accepted: 07/17/2013] [Indexed: 12/14/2022]
Abstract
Xenotransplantation using pigs as donors offers the possibility of eliminating the chronic shortage of donor kidneys, but there are several obstacles to be overcome before this goal can be achieved. Preclinical studies have shown that, while porcine renal xenografts are broadly compatible physiologically, they provoke a complex rejection process involving preformed and elicited antibodies, heightened innate immune cell reactivity, dysregulated coagulation, and a strong T cell-mediated adaptive response. Furthermore, the susceptibility of the xenograft to proinflammatory and procoagulant stimuli is probably increased by cross-species molecular defects in regulatory pathways. To balance these disadvantages, xenotransplantation has at its disposal a unique tool to address particular rejection mechanisms and incompatibilities: genetic modification of the donor. This review focuses on the pathophysiology of porcine renal xenograft rejection, and on the significant genetic, pharmacological, and technical progress that has been made to prolong xenograft survival.
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Affiliation(s)
- Peter J Cowan
- 1] Immunology Research Centre, St Vincent's Hospital, Melbourne, Victoria, Australia [2] Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia
| | - David K C Cooper
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Anthony J F d'Apice
- 1] Immunology Research Centre, St Vincent's Hospital, Melbourne, Victoria, Australia [2] Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia
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35
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Is there a correlation between anti-pig antibody levels in humans and geographic location during childhood? Transplantation 2013; 96:387-93. [PMID: 23887601 DOI: 10.1097/tp.0b013e3182992a84] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND An initial observation suggested high levels of anti-pig antibodies in healthy humans who had spent their childhood in the Middle East. We tested larger cohorts to determine whether anti-pig antibody levels correlated with the geographic location in which the subject spent his/her childhood, because this might have implications for clinical trials of xenotransplantation. METHODS Anti-pig IgM and IgG levels (by flow cytometry using peripheral blood mononuclear cells from wild-type and α1,3-galactosyltransferase gene-knockout pigs) and anti-Gal IgM and IgG levels (by enzyme-linked immunosorbent assay) were measured in 75 volunteers. Comparisons of antibody levels were also made based on subject age, gender, ABO blood group, diet, and history of vaccination. RESULTS Antibody binding to α1,3-galactosyltransferase gene-knockout pig cells was less than to wild-type cells. There was a reduction in anti-pig IgM and anti-Gal IgM, but a slight increase in anti-nonGal IgG, with age. Women had higher levels of anti-Gal IgM than men. Blood group A subjects had higher levels of anti-pig IgM and IgG than those of group AB. Diet had no influence on antibody levels. Typhoid or measles-mumps-rubella vaccination was associated with lower anti-nonGal IgG or anti-Gal IgG, respectively, whereas influenza vaccination was associated with higher anti-nonGal IgG. There were some significant variations in antibody levels associated with location during childhood, with subjects from the Middle East demonstrating higher anti-nonGal IgG and anti-Gal IgG. CONCLUSION Clinical trials of xenotransplantation may be influenced by various factors, including the geographic location of the recipient during childhood, possibly associated with exposure to different microorganisms.
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Deng L, Chen X, Varki A. Exploration of sialic acid diversity and biology using sialoglycan microarrays. Biopolymers 2013; 99:650-65. [PMID: 23765393 PMCID: PMC7161822 DOI: 10.1002/bip.22314] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2013] [Accepted: 06/04/2013] [Indexed: 12/13/2022]
Abstract
Sialic acids (Sias) are a group of α-keto acids with a nine-carbon backbone, which display many types of modifications in nature. The diversity of natural Sia presentations is magnified by a variety of glycosidic linkages to underlying glycans, the sequences and classes of such glycans, as well as the spatial organization of Sias with their surroundings. This diversity is closely linked to the numerous and varied biological functions of Sias. Relatively large libraries of natural and unnatural Sias have recently been chemically/chemoenzymatically synthesized and/or isolated from natural sources. The resulting sialoglycan microarrays have proved to be valuable tools for the exploration of diversity and biology of Sias. Here we provide an overview of Sia diversity in nature, the approaches used to generate sialoglycan microarrays, and the achievements and challenges arising.
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Affiliation(s)
- Lingquan Deng
- Departments of Medicine and Cellular & Molecular MedicineGlycobiology Research and Training Center, University of CaliforniaSan Diego, La JollaCA92093‐0687
| | - Xi Chen
- Department of ChemistryUniversity of CaliforniaDavisCA95616
| | - Ajit Varki
- Departments of Medicine and Cellular & Molecular MedicineGlycobiology Research and Training Center, University of CaliforniaSan Diego, La JollaCA92093‐0687
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Hara H, Bentall A, Long C, Fang J, Andreyev O, Lunz J, Ezzelarab M, Abu-Elmagd KM, Shapiro R, Ayares D, Stegall M, Cooper DKC. Minimal effect of bortezomib in reducing anti-pig antibodies in human leukocyte antigen-sensitized patients: a pilot study. Xenotransplantation 2013; 20:429-37. [PMID: 23998233 DOI: 10.1111/xen.12052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 07/31/2013] [Indexed: 12/24/2022]
Abstract
BACKGROUND Bortezomib, a proteasome inhibitor used to treat multiple myeloma, has been administered (± plasma exchange ± intravenous immunoglobulin [IVIg]) in attempts to reduce antibodies against human leukocyte antigens (HLA) in sensitized patients undergoing organ transplantation. To our knowledge, bortezomib has not been investigated for its effect on natural anti-pig antibodies. If bortezomib could reduce the production of anti-pig antibodies, this would likely be beneficial to the outcome of pig organ grafts in primates. METHODS Nine patients received bortezomib either to reduce anti-HLA antibody levels before organ allotransplantation or to treat antibody-mediated rejection. Patients at the Mayo Clinic (Group 1; n = 4) received bortezomib alone, whereas at the UPMC (Group 2; n = 5), this was combined with plasmaphereses ± IVIg in some cases. Anti-pig IgM and IgG levels against wild-type (WT) and α1,3-galactosyltransferase gene knockout (GTKO) pig aortic endothelial cells (flow cytometry-relative mean fluorescence intensity) and anti-Gal IgM and IgG (ELISA-OD480 nm ) were measured pre- and post-bortezomib therapy. RESULTS Mean anti-pig IgM levels were 11.2 (WT) and 1.9 (GTKO) pre-bortezomib treatment and 9.4 (WT: P = 0.02) and 1.7 (GTKO: P = 0.33) post-bortezomib treatment, respectively. Mean anti-pig IgG levels were 4.3 (WT) and 1.5 (GTKO) pre-bortezomib treatment and 3.6 (WT: P = 0.21) and 1.4 (GTKO: P = 0.20) post-bortezomib treatment, respectively. Mean anti-Gal IgM and IgG levels were 0.7 and 1.1, respectively, pre-treatment, and 0.6 (P = 0.03) and 1.1 (NS), respectively, post-treatment. When the data were analyzed in Groups 1 and 2 separately, there were no significant differences between the pre- and post-bortezomib levels of anti-pig, anti-non-Gal, or anti-Gal IgM or IgG. CONCLUSIONS From this limited study, we conclude that bortezomib might reduce anti-Gal IgM levels in primates, but, in this respect alone, is unlikely to have any significant effect on the outcome of GTKO pig organ transplantation.
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Affiliation(s)
- Hidetaka Hara
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
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Byrne GW, Azimzadeh AM, Ezzelarab M, Tazelaar HD, Ekser B, Pierson RN, Robson SC, Cooper DKC, McGregor CGA. Histopathologic insights into the mechanism of anti-non-Gal antibody-mediated pig cardiac xenograft rejection. Xenotransplantation 2013; 20:292-307. [PMID: 25098626 PMCID: PMC4126170 DOI: 10.1111/xen.12050] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 07/31/2013] [Indexed: 01/13/2023]
Abstract
The histopathology of cardiac xenograft rejection has evolved over the last 20 yr with the development of new modalities for limiting antibody-mediated injury, advancing regimens for immune suppression, and an ever-widening variety of new donor genetics. These new technologies have helped us progress from what was once an overwhelming anti-Gal-mediated hyperacute rejection to a more protracted anti-Gal-mediated vascular rejection to what is now a more complex manifestation of non-Gal humoral rejection and coagulation dysregulation. This review summarizes the changing histopathology of Gal- and non-Gal-mediated cardiac xenograft rejection and discusses the contributions of immune-mediated injury, species-specific immune-independent factors, transplant and therapeutic procedures, and donor genetics to the overall mechanism(s) of cardiac xenograft rejection.
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Affiliation(s)
- Guerard W Byrne
- Institute of Cardiovascular Science, University College London, London, UK; Department of Surgery, Mayo Clinic, Rochester, MN, USA
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Galili U. α1,3Galactosyltransferase knockout pigs produce the natural anti-Gal antibody and simulate the evolutionary appearance of this antibody in primates. Xenotransplantation 2013; 20:267-76. [PMID: 23968556 DOI: 10.1111/xen.12051] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 07/31/2013] [Indexed: 11/27/2022]
Abstract
BACKGROUND Anti-Gal is the most abundant natural antibody in humans and Old World primates (apes and Old World monkeys). Its ligand, the α-gal epitope (Galα1-3Galβ1-4GlcNAc-R), is abundant in nonprimate mammals, prosimians and New World monkeys whereas it is absent in humans and Old World primates as a result of inactivation of the α1,3galactosyltransferase (α1,3GT) gene in ancestral Old World primates, as recent as 20-28 million years ago. Since anti-Gal has been a "forbidden" autoantibody for >140 million years of evolution in mammals producing α-gal epitopes it was of interest to determine whether ancestral Old World primates could produce anti-Gal once α-gal epitopes were eliminated, i.e. did they carry anti-Gal encoding immunoglobulin genes, or did evolutionary selection eliminate these genes that may be detrimental in mammals synthesizing α-gal epitopes. This question was studied by evaluating anti-Gal prodution in α1,3GT knockout (GT-KO) pigs recently generated from wild-type pigs in which the α-gal epitope is a major self-antigen. METHODS Anti-Gal antibody activity in pig sera was assessed by ELISA, flow cytometry and complement mediated cytolysis and compared to that in human sera. RESULTS The study demonstrates abundant production of the natural anti-Gal antibody in GT-KO pigs at titers even higher than in humans. The fine specificity of GT-KO pig anti-Gal is identical to that of human anti-Gal. CONCLUSIONS Pigs and probably other mammals producing α-gal epitopes carry immunoglobulin genes encoding anti-Gal as an autoantibody. Once the α-gal epitope is eliminated in GT-KO pigs, they produce anti-Gal. These findings strongly suggest that similar to GT-KO pigs, inactivation of the α1,3GT gene in ancestral Old World primates enabled the immediate production of anti-Gal, possibly as a protective antibody against detrimental microbial agents carrying α-gal epitopes.
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Affiliation(s)
- Uri Galili
- Department of Surgery, University of Massachusetts Medical School, Worcester, MA, USA
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Jang KS, Kim YG, Adhya M, Park HM, Kim BG. The sweets standing at the borderline between allo- and xenotransplantation. Xenotransplantation 2013; 20:199-208. [PMID: 23551837 DOI: 10.1111/xen.12030] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 02/28/2013] [Indexed: 01/06/2023]
Abstract
Animal cells are densely covered with glycoconjugates, such as N-glycan, O-glycan, and glycosphingolipids, which are important for various biological and immunological events at the cell surface and in the extracellular matrix. Endothelial α-Gal carbohydrate epitopes (Galα3Gal-R) expressed on porcine tissue or cell surfaces are such glycoconjugates and directly mediate hyperacute immunological rejection in pig-to-human xenotransplantation. Although researchers have been able to develop α1,3-galactosyltransferase (GalT) gene knockout (KO) pigs, there remain unclarified non-Gal antigens that prevent xenotransplantation. Based on our expertise in the structural analysis of xenoantigenic carbohydrates, we describe the immunologically significant non-human carbohydrate antigens, including α-Gal antigens, analyzed as part of efforts to assess the antigens responsible for hyperacute immunological rejection in pig-to-human xenotransplantation. The importance of studying human, pig, and GalT-KO pig glycoprofiles, and of developing adequate pig-to-human glycan databases, is also discussed.
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Affiliation(s)
- Kyoung-Soon Jang
- Institute of Molecular Biology and Genetics, Interdisciplinary Program for Biochemical Engineering and Biotechnology, Seoul National University, Seoul, Korea
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Tumor-associated glycans and their role in gynecological cancers: accelerating translational research by novel high-throughput approaches. Metabolites 2012; 2:913-39. [PMID: 24957768 PMCID: PMC3901231 DOI: 10.3390/metabo2040913] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 11/08/2012] [Accepted: 11/09/2012] [Indexed: 02/06/2023] Open
Abstract
Glycans are important partners in many biological processes, including carcinogenesis. The rapidly developing field of functional glycomics becomes one of the frontiers of biology and biomedicine. Aberrant glycosylation of proteins and lipids occurs commonly during malignant transformation and leads to the expression of specific tumor-associated glycans. The appearance of aberrant glycans on carcinoma cells is typically associated with grade, invasion, metastasis and overall poor prognosis. Cancer-associated carbohydrates are mostly located on the surface of cancer cells and are therefore potential diagnostic biomarkers. Currently, there is increasing interest in cancer-associated aberrant glycosylation, with growing numbers of characteristic cancer targets being detected every day. Breast and ovarian cancer are the most common and lethal malignancies in women, respectively, and potential glycan biomarkers hold promise for early detection and targeted therapies. However, the acceleration of research and comprehensive multi-target investigation of cancer-specific glycans could only be successfully achieved with the help of a combination of novel high-throughput glycomic approaches.
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Fang J, Walters A, Hara H, Long C, Yeh P, Ayares D, Cooper DKC, Bianchi J. Anti-gal antibodies in α1,3-galactosyltransferase gene-knockout pigs. Xenotransplantation 2012; 19:305-10. [PMID: 22970769 DOI: 10.1111/j.1399-3089.2012.00710.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Serum anti-galactose-α1,3-galactose (Gal) IgM and IgG antibody levels were measured by ELISA in α1,3-galactosyltransferase gene-knockout (GTKO) pigs (78 estimations in 47 pigs). A low level of anti-Gal IgM was present soon after birth, and rose to a peak at 4-6 m, which was maintained thereafter even in the oldest pigs tested (at >2 yr). Anti-Gal IgG was also present at birth, peaked at 3 m, and after 6 m steadily decreased until almost undetectable at 20 m. No differences in this pattern were seen between pigs of different gender. Total IgM followed a similar pattern as anti-Gal IgM, but total IgG did not decrease after 6m. The data provide useful baseline data for future experimental studies in GTKO pigs, e.g., relating to the antibody response to WT pig allografts.
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Affiliation(s)
- Jason Fang
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA 15261, USA
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Naso F, Gandaglia A, Iop L, Spina M, Gerosa G. Alpha-Gal detectors in xenotransplantation research: a word of caution. Xenotransplantation 2012; 19:215-20. [DOI: 10.1111/j.1399-3089.2012.00714.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
There have been significant advances in organ xenotransplantation (cross-species transplantation), especially in the development of genetically engineered pigs, but clinical trials of solid organ transplants are still a time away. However, there is a form of pig-to-human xenotransplantation that has been taking place since the 1960s-bioprosthetic heart valve (BHV) replacement. Recently, there has been increasing evidence that, despite glutaraldehyde fixation of BHVs, there is a significant immune reaction to the valves, leading to calcification, rapid structural deterioration, and failure, particularly in young patients who have a more vigorous immune system and metabolism than the elderly. However, it is the young patients who would most benefit from such BHVs because these avoid the complications associated with the lifelong anticoagulation required with mechanical valves. In this review, we examine pathologic and immunohistochemical reports of failed BHVs that suggest that there is an immune response to these valves. Small animal studies that link the development of calcification and BHV failure to the immune response are reviewed. We draw parallels between the problems of glutaraldehyde-fixed tissue xenotransplantation and those currently being faced in live organ xenotransplantation. Finally, we discuss the advances being made in the production of genetically modified pigs and the evidence that these pigs may become a source of BHVs that can be used worldwide to treat valvular heart disease in children and young adults (for whom there is no ideal valve replacement in existence today). The design of a BHV that is resistant to the host's immune response would be a major step forward in cardiac surgery.
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Wilhite T, Ezzelarab C, Hara H, Long C, Ayares D, Cooper DKC, Ezzelarab M. The effect of Gal expression on pig cells on the human T-cell xenoresponse. Xenotransplantation 2012; 19:56-63. [PMID: 22360754 DOI: 10.1111/j.1399-3089.2011.00691.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Lack of Gal expression on pig cells is associated with a reduced primate humoral immune response as well as a reduction in cytokine production by human cells in vitro. We investigated whether lack of Gal expression is associated with reduced human T-cell response in vitro. METHODS Peripheral blood mononuclear cells (PBMCs) were obtained from healthy humans and naïve baboons. Human CD4+ and CD8+ T cells were isolated. Porcine aortic endothelial cells (pAECs) were isolated from wild-type (WT) and α1,3-galactosyltransferase gene-knockout (GTKO) pigs. WT pAECs were treated with α-galactosidase, reducing Gal expression. Swine leukocyte antigen (SLA) class I and II expression on pAECs was measured, as was T-cell proliferation and cytokine production in response to pAECs. RESULTS Reduced Gal expression on WT pAECs after α-galactosidase treatment was associated with reduced human PBMC proliferation (P<0.005). SLA class I and II expression on WT and GTKO pAECs was comparable. Human CD4+ and CD8+ T-cell proliferation was less against GTKO pAECs before (P<0.001) and after (P<0.01 and P<0.05, respectively) activation. Human and baboon PBMC proliferation was less against GTKO pAECs before (P<0.05) and after (P<0.01 and P<0.05, respectively) activation. Human PBMCs produced a comparable cytokine/chemokine response to WT and GTKO pAECs. However, there was less production of IFN-γ/TNF-α by CD4+ and IFN-γ/granzyme B/IP-10 by CD8+ T cells in response to GTKO pAECs. CONCLUSIONS The absence of Gal on pig cells is associated with reduced human T-cell proliferation (and possibly selected cytokine production). Adaptive primate T-cell responses are likely to be reduced in GTKO xenograft recipients.
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Affiliation(s)
- Tyler Wilhite
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA 15261, USA
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Cooper DKC, Ekser B, Burlak C, Ezzelarab M, Hara H, Paris L, Tector AJ, Phelps C, Azimzadeh AM, Ayares D, Robson SC, Pierson RN. Clinical lung xenotransplantation--what donor genetic modifications may be necessary? Xenotransplantation 2012; 19:144-58. [PMID: 22702466 PMCID: PMC3775598 DOI: 10.1111/j.1399-3089.2012.00708.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Barriers to successful lung xenotransplantation appear to be even greater than for other organs. This difficulty may be related to several macro anatomic factors, such as the uniquely fragile lung parenchyma and associated blood supply that results in heightened vulnerability of graft function to segmental or lobar airway flooding caused by loss of vascular integrity (also applicable to allotransplants). There are also micro-anatomic considerations, such as the presence of large numbers of resident inflammatory cells, such as pulmonary intravascular macrophages and natural killer (NK) T cells, and the high levels of von Willebrand factor (vWF) associated with the microvasculature. We have considered what developments would be necessary to allow successful clinical lung xenotransplantation. We suggest this will only be achieved by multiple genetic modifications of the organ-source pig, in particular to render the vasculature resistant to thrombosis. The major problems that require to be overcome are multiple and include (i) the innate immune response (antibody, complement, donor pulmonary and recipient macrophages, monocytes, neutrophils, and NK cells), (ii) the adaptive immune response (T and B cells), (iii) coagulation dysregulation, and (iv) an inflammatory response (e.g., TNF-α, IL-6, HMGB1, C-reactive protein). We propose that the genetic manipulation required to provide normal thromboregulation alone may include the introduction of genes for human thrombomodulin/endothelial protein C-receptor, and/or tissue factor pathway inhibitor, and/or CD39/CD73; the problem of pig vWF may also need to be addressed. It would appear that exploration of every available therapeutic path will be required if lung xenotransplantation is to be successful. To initiate a clinical trial of lung xenotransplantation, even as a bridge to allotransplantation (with a realistic possibility of survival long enough for a human lung allograft to be obtained), significant advances and much experimental work will be required. Nevertheless, with the steadily increasing developments in techniques of genetic engineering of pigs, we are optimistic that the goal of successful clinical lung xenotransplantation can be achieved within the foreseeable future. The optimistic view would be that if experimental pig lung xenotransplantation could be successfully managed, it is likely that clinical application of this and all other forms of xenotransplantation would become more feasible.
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Affiliation(s)
- David K C Cooper
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA 15261, USA.
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Dons EM, Montoya C, Long CE, Hara H, Echeverri GJ, Ekser B, Ezzelarab C, Medellin DR, van der Windt DJ, Murase N, Rigatti LH, Wagner R, Wolf RF, Ezzelarab M, West LJ, Ijzermans JNM, Cooper DKC. T-cell-based immunosuppressive therapy inhibits the development of natural antibodies in infant baboons. Transplantation 2012; 93:769-76. [PMID: 22441321 PMCID: PMC3776575 DOI: 10.1097/tp.0b013e3182481168] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND We set out to determine whether B-cell tolerance to A/B-incompatible alloantigens and pig xenoantigens could be achieved in infant baboons. METHODS Artery patch grafts were implanted in the abdominal aorta in 3-month-old baboons using A/B-incompatible (AB-I) allografts or wild-type pig xenografts (pig). Group 1 (Gp1) (controls, n=6) received no immunosuppressive therapy (IS) and no graft. Gp2 (n=2) received an AB-I or pig graft but no IS. Gp3 received AB-I grafts+IS (Gp3A: n=2) or pig grafts+IS (Gp3B: n=2). IS consisted of ATG, anti-CD154mAb, and mycophenolate mofetil until age 8 to 12 months. Gp4 (n=2) received IS only but no graft. RESULTS In Gp1, anti-A/B and cytotoxic anti-pig immunoglobulin-M increased steadily during the first year. Gp2 became sensitized to donor-specific AB-I or pig antigens within 2 weeks. Gp3 and Gp4 infants that received anti-CD154mAb made no or minimal anti-A/B and anti-pig antibodies while receiving IS. DISCUSSION The production of natural anti-A/B and anti-pig antibodies was inhibited by IS with anti-CD154mAb, even in the absence of an allograft or xenograft, suggesting that natural antibodies may not be entirely T-cell independent. These data are in contrast to clinical experience with AB-I allotransplantation in infants, who cease producing only donor-specific antibodies.
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Affiliation(s)
- Eefje M. Dons
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA
- Department of Surgery, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Claudia Montoya
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA
| | - Cassandra E. Long
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA
| | - Hidetaka Hara
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA
| | - Gabriel J. Echeverri
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA
| | - Burcin Ekser
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA
| | - Corin Ezzelarab
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA
| | - Dasha Roa Medellin
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA
| | - Dirk J. van der Windt
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA
- Department of Surgery, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Noriko Murase
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA
| | - Lora H. Rigatti
- Division of Laboratory Animal Resources, University of Pittsburgh, Pittsburgh, PA
| | - Robert Wagner
- Division of Laboratory Animal Resources, University of Pittsburgh, Pittsburgh, PA
| | - Roman F. Wolf
- Comparative Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Mohamed Ezzelarab
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA
| | - Lori J. West
- Department of Pediatrics, Cardiac Transplant Research, University of Alberta, Edmonton, AL, Canada
| | - Jan N. M. Ijzermans
- Department of Surgery, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
| | - David K. C. Cooper
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA
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Burlak C, Wang ZY, Chihara RK, Lutz AJ, Wang Y, Estrada JL, Tector AJ. Identification of human preformed antibody targets in GTKO pigs. Xenotransplantation 2012; 19:92-101. [DOI: 10.1111/j.1399-3089.2012.00695.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Abstract
PURPOSE OF REVIEW Cardiac xenotransplantation (CXTx) remains a promising approach to alleviate the chronic shortage of donor hearts. This review summarizes recent results of heterotopic and orthotopic CXTx, highlights the role of non-Gal antibody in xenograft rejection, and discusses challenges to clinical orthotopic CXTx. RECENT FINDINGS Pigs mutated in the α 1,3 galactosyltransferase gene (GTKO pigs) are devoid of the galactose α1,3 galactose (αGal) carbohydrate antigen. This situation effectively eliminates any role for anti-Gal antibody in GTKO cardiac xenograft rejection. Survival of heterotopic GTKO cardiac xenografts in nonhuman primates continues to increase. GTKO graft rejection commonly involves vascular antibody deposition and variable complement deposition. Non-Gal antibody responses to porcine antigens associated with inflammation, complement, and hemostatic regulation and to new carbohydrate antigens have been identified. Their contribution to rejection remains under investigation. Orthotopic CXTx is limited by early perioperative cardiac xenograft dysfunction (PCXD). However, hearts affected by PCXD recover full cardiac function and orthotopic survival up to 2 months without rejection has been reported. SUMMARY CXTx remains a promising technology for treating end-stage cardiac failure. Genetic modification of the donor and refinement of immunosuppressive regimens have extended heterotopic cardiac xenograft survival from minutes to in excess of 8 months.
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Affiliation(s)
- Guerard W Byrne
- University College London, Institute for Cardiovascular Sciences, London, UK.
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Abstract
Anti-non gal antibodies are produced in xenograft recipients against multiple xenogeneic antigens. Studies in monkeys transplanted with pig organs lacking α-gal epitopes have suggested that anti-non gal antibodies mediate acute and chronic rejection of xenografts. This overview describes studies of these antibodies in patients who received xenografts and includes (1) an ovarian carcinoma patient receiving three intraperitoneal infusions of mouse fibroblasts in a gene therapy study, (2) orthopedic patients with torn anterior cruciate ligament replaced by a ligament made of pig patellar tendon, and (3) diabetic patients receiving fetal pig islet cell clusters xenograft together with a kidney allograft. Anti-non gal antibodies were found to be continuously produced as long as the xenograft was present in the recipient and were directed against a large number of pig proteins. Monitoring the immune response in the recipient of mouse fibroblasts indicated that the production of anti-non gal antibodies is much slower than that of the anti-Gal antibody, suggesting that they are generated by multiple B-cell clones, each initially comprising relatively few cells. Potent immunosuppression to prevent allograft rejection does not fully inhibit the production of anti-non gal antibodies. Much of this antibody response seems to be due to the differences in amino acid sequences between pig and human orthologous proteins as a result of evolutionary mutations. Overcoming the anti-non gal antibody barrier will require immunosuppressive agents that preferentially inhibit this immune response while maintaining protection against pathogens, or alternatively development of methods for induction of immune tolerance to xenogeneic pig antigens.
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