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Vafadar A, Vosough P, Jahromi HK, Tajbakhsh A, Savardshtaki A, Butler AE, Sahebkar A. The role of efferocytosis and transplant rejection: Strategies in promoting transplantation tolerance using apoptotic cell therapy and/or synthetic particles. Cell Biochem Funct 2023; 41:959-977. [PMID: 37787641 DOI: 10.1002/cbf.3852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 07/26/2023] [Accepted: 08/24/2023] [Indexed: 10/04/2023]
Abstract
Recently, efforts have been made to recognize the precise reason(s) for transplant failure and the process of rejection utilizing the molecular signature. Most transplant recipients do not appreciate the unknown length of survival of allogeneic grafts with the existing standard of care. Two noteworthy immunological pathways occur during allogeneic transplant rejection. A nonspecific innate immune response predominates in the early stages of the immune reaction, and allogeneic antigens initiate a donor-specific adaptive reaction. Though the adaptive response is the major cause of allograft rejection, earlier pro-inflammatory responses that are part of the innate immune response are also regarded as significant in graft loss. The onset of the innate and adaptive immune response causes chronic and acute transplant rejection. Currently employed immunosuppressive medications have shown little or no influence on chronic rejection and, as a result, on overall long-term transplant survival. Furthermore, long-term pharmaceutical immunosuppression is associated with side effects, toxicity, and an increased risk of developing diseases, both infectious and metabolic. As a result, there is a need for the development of innovative donor-specific immunosuppressive medications to regulate the allorecognition pathways that induce graft loss and to reduce the side effects of immunosuppression. Efferocytosis is an immunomodulatory mechanism with fast and efficient clearance of apoptotic cells (ACs). As such, AC therapy strategies have been suggested to limit transplant-related sequelae. Efferocytosis-based medicines/treatments can also decrease the use of immunosuppressive drugs and have no detrimental side effects. Thus, this review aims to investigate the impact of efferocytosis on transplant rejection/tolerance and identify approaches using AC clearance to increase transplant viability.
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Affiliation(s)
- Asma Vafadar
- Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Parisa Vosough
- Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Hossein Kargar Jahromi
- Research Center for Non-Communicable Disease, Jahrom University of Medical Sciences, Jahrom, Iran
| | - Amir Tajbakhsh
- Department of Molecular Medicine, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Amir Savardshtaki
- Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran
- Infertility Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Alexandra E Butler
- Research Department, Royal College of Surgeons in Ireland - Bahrain, Adliya, Bahrain
| | - Amirhossein Sahebkar
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
- Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Biotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
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Lu TY, Xu XL, Du XG, Wei JH, Yu JN, Deng SL, Qin C. Advances in Innate Immunity to Overcome Immune Rejection during Xenotransplantation. Cells 2022; 11:cells11233865. [PMID: 36497122 PMCID: PMC9735653 DOI: 10.3390/cells11233865] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/26/2022] [Accepted: 11/28/2022] [Indexed: 12/03/2022] Open
Abstract
Transplantation is an effective approach for treating end-stage organ failure. There has been a long-standing interest in xenotransplantation as a means of increasing the number of available organs. In the past decade, there has been tremendous progress in xenotransplantation accelerated by the development of rapid gene-editing tools and immunosuppressive therapy. Recently, the heart and kidney from pigs were transplanted into the recipients, which suggests that xenotransplantation has entered a new era. The genetic discrepancy and molecular incompatibility between pigs and primates results in barriers to xenotransplantation. An increasing body of evidence suggests that innate immune responses play an important role in all aspects of the xenogeneic rejection. Simultaneously, the role of important cellular components like macrophages, natural killer (NK) cells, and neutrophils, suggests that the innate immune response in the xenogeneic rejection should not be underestimated. Here, we summarize the current knowledge about the innate immune system in xenotransplantation and highlight the key issues for future investigations. A better understanding of the innate immune responses in xenotransplantation may help to control the xenograft rejection and design optimal combination therapies.
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Affiliation(s)
- Tian-Yu Lu
- NHC Key Laboratory of Human Disease Comparative Medicine, Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, National Human Diseases Animal Model Resource Center, Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, International Center for Technology and Innovation of animal model, Beijing 100021, China
| | - Xue-Ling Xu
- National Engineering Laboratory of Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Xu-Guang Du
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Jin-Hua Wei
- Cardiovascular Surgery Department, Center of Laboratory Medicine, National Center for Cardiovascular Diseases, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China
| | - Jia-Nan Yu
- NHC Key Laboratory of Human Disease Comparative Medicine, Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, National Human Diseases Animal Model Resource Center, Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, International Center for Technology and Innovation of animal model, Beijing 100021, China
| | - Shou-Long Deng
- NHC Key Laboratory of Human Disease Comparative Medicine, Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, National Human Diseases Animal Model Resource Center, Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, International Center for Technology and Innovation of animal model, Beijing 100021, China
- Correspondence: (S.-L.D.); (C.Q.)
| | - Chuan Qin
- NHC Key Laboratory of Human Disease Comparative Medicine, Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, National Human Diseases Animal Model Resource Center, Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, International Center for Technology and Innovation of animal model, Beijing 100021, China
- Changping National Laboratory (CPNL), Beijing 102206, China
- Correspondence: (S.-L.D.); (C.Q.)
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Sykes M, Sachs DH. Progress in xenotransplantation: overcoming immune barriers. Nat Rev Nephrol 2022; 18:745-761. [PMID: 36198911 DOI: 10.1038/s41581-022-00624-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/19/2022] [Indexed: 11/09/2022]
Abstract
A major limitation of organ allotransplantation is the insufficient supply of donor organs. Consequently, thousands of patients die every year while waiting for a transplant. Progress in xenotransplantation that has permitted pig organ graft survivals of years in non-human primates has led to renewed excitement about the potential of this approach to alleviate the organ shortage. In 2022, the first pig-to-human heart transplant was performed on a compassionate use basis, and xenotransplantation experiments using pig kidneys in deceased human recipients provided encouraging data. Many advances in xenotransplantation have resulted from improvements in the ability to genetically modify pigs using CRISPR-Cas9 and other methodologies. Gene editing has the capacity to generate pig organs that more closely resemble those of humans and are hence more physiologically compatible and less prone to rejection. Despite such modifications, immune responses to xenografts remain powerful and multi-faceted, involving innate immune components that do not attack allografts. Thus, the induction of innate and adaptive immune tolerance to prevent rejection while preserving the capacity of the immune system to protect the recipient and the graft from infection is desirable to enable clinical xenotransplantation.
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Affiliation(s)
- Megan Sykes
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University, New York, NY, USA. .,Department of Surgery, Columbia University, New York, NY, USA. .,Department of Microbiology and Immunology, Columbia University, New York, NY, USA.
| | - David H Sachs
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University, New York, NY, USA. .,Department of Surgery, Columbia University, New York, NY, USA.
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4
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Maeda A, Kogata S, Toyama C, Lo PC, Okamatsu C, Yamamoto R, Masahata K, Kamiyama M, Eguchi H, Watanabe M, Nagashima H, Okuyama H, Miyagawa S. The Innate Cellular Immune Response in Xenotransplantation. Front Immunol 2022; 13:858604. [PMID: 35418992 PMCID: PMC8995651 DOI: 10.3389/fimmu.2022.858604] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 02/23/2022] [Indexed: 01/02/2023] Open
Abstract
Xenotransplantation is very attractive strategy for addressing the shortage of donors. While hyper acute rejection (HAR) caused by natural antibodies and complement has been well defined, this is not the case for innate cellular xenogeneic rejection. An increasing body of evidence suggests that innate cellular immune responses contribute to xenogeneic rejection. Various molecular incompatibilities between receptors and their ligands across different species typically have an impact on graft outcome. NK cells are activated by direct interaction as well as by antigen dependent cellular cytotoxicity (ADCC) mechanisms. Macrophages are activated through various mechanisms in xenogeneic conditions. Macrophages recognize CD47 as a "marker of self" through binding to SIRPα. A number of studies have shown that incompatibility of porcine CD47 against human SIRPα contributes to the rejection of xenogeneic target cells by macrophages. Neutrophils are an early responder cell that infiltrates xenogeneic grafts. It has also been reported that neutrophil extracellular traps (NETs) activate macrophages as damage-associated pattern molecules (DAMPs). In this review, we summarize recent insights into innate cellular xenogeneic rejection.
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Affiliation(s)
- Akira Maeda
- Department of Promotion for Blood and Marrow Transplantation, Aichi Medical University School of Medicine, Nagakute, Japan.,Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Suita, Japan
| | - Shuhei Kogata
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Suita, Japan
| | - Chiyoshi Toyama
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Suita, Japan
| | - Pei-Chi Lo
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Suita, Japan
| | - Chizu Okamatsu
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Suita, Japan
| | - Riho Yamamoto
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Suita, Japan
| | - Kazunori Masahata
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Suita, Japan
| | - Masafumi Kamiyama
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Suita, Japan
| | - Hiroshi Eguchi
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Suita, Japan
| | - Masahito Watanabe
- International Institute for Bio-Resource Research, Meiji University, Kawasaki, Japan
| | - Hiroshi Nagashima
- International Institute for Bio-Resource Research, Meiji University, Kawasaki, Japan
| | - Hiroomi Okuyama
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Suita, Japan
| | - Shuji Miyagawa
- Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Suita, Japan.,International Institute for Bio-Resource Research, Meiji University, Kawasaki, Japan
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5
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Podestà MA, Sykes M. Chimerism-Based Tolerance to Kidney Allografts in Humans: Novel Insights and Future Perspectives. Front Immunol 2022; 12:791725. [PMID: 35069574 PMCID: PMC8767096 DOI: 10.3389/fimmu.2021.791725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 12/15/2021] [Indexed: 11/18/2022] Open
Abstract
Chronic rejection and immunosuppression-related toxicity severely affect long-term outcomes of kidney transplantation. The induction of transplantation tolerance – the lack of destructive immune responses to a transplanted organ in the absence of immunosuppression – could potentially overcome these limitations. Immune tolerance to kidney allografts from living donors has been successfully achieved in humans through clinical protocols based on chimerism induction with hematopoietic cell transplantation after non-myeloablative conditioning. Notably, two of these protocols have led to immune tolerance in a significant fraction of HLA-mismatched donor-recipient combinations, which represent the large majority of cases in clinical practice. Studies in mice and large animals have been critical in dissecting tolerance mechanisms and in selecting the most promising approaches for human translation. However, there are several key differences in tolerance induction between these models and humans, including the rate of success and stability of donor chimerism, as well as the relative contribution of different mechanisms in inducing donor-specific unresponsiveness. Kidney allograft tolerance achieved through durable full-donor chimerism may be due to central deletion of graft-reactive donor T cells, even though mechanistic data from patient series are lacking. On the other hand, immune tolerance attained with transient mixed chimerism-based protocols initially relies on Treg-mediated suppression, followed by peripheral deletion of donor-reactive recipient T-cell clones under antigenic pressure from the graft. These conclusions were supported by data deriving from novel high-throughput T-cell receptor sequencing approaches that allowed tracking of alloreactive repertoires over time. In this review, we summarize the most important mechanistic studies on tolerance induction with combined kidney-bone marrow transplantation in humans, discussing open issues that still need to be addressed and focusing on techniques developed in recent years to efficiently monitor the alloresponse in tolerance trials. These cutting-edge methods will be instrumental for the development of immune tolerance protocols with improved efficacy and to identify patients amenable to safe immunosuppression withdrawal.
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Affiliation(s)
- Manuel Alfredo Podestà
- Renal Division, ASST Santi Paolo e Carlo, Department of Health Sciences, University of Milan, Milano, Italy
| | - Megan Sykes
- Columbia Center for Translational Immunology, Department of Medicine, Department of Surgery, Department of Microbiology and Immunology, Columbia University, New York, NY, United States
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Furuya K, Zheng YW, Ge JY, Zhang L, Furuta T, Liang C, Abe H, Yagi H, Hamada H, Isoda H, Hui L, Ohkohchi N, Oda T. The evidence of a macrophage barrier in the xenotransplantation of human hematopoietic stem cells to severely immunodeficient rats. Xenotransplantation 2021; 28:e12702. [PMID: 34145650 DOI: 10.1111/xen.12702] [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: 01/04/2021] [Revised: 04/15/2021] [Accepted: 06/02/2021] [Indexed: 11/29/2022]
Abstract
BACKGROUND The human-to-rat hematopoietic stem cell transplantation (HSCT) model is rare, unlike its human-to-mouse counterpart. The rat models are desired, especially in areas of physiology, toxicology, and pharmacology. In addition to lymphocytes, macrophages are also considered to be important for xenotransplantation. We generated a rat xenotransplantation model to prove the role of macrophages as a xenotransplantation barrier. METHODS Immunodeficiency in SRG rats, which are Sprague-Dawley (SD) rats lacking Rag2 and Il2rg, was confirmed by flow cytometry and spleen immunostaining. Human umbilical cord blood was collected after scheduled cesarean section at the University of Tsukuba Hospital. Cord blood mononuclear cells (CB-MNCs) were transplanted into the SRG rats administered several injections of clodronate liposome (CL), which cause macrophage depletion. Survival of human cells was observed by flow cytometry. Rat macrophage phagocytosis assay was performed to check the species-specific effects of rat macrophages on injected human/rat blood cells. RESULTS SRG rats were deficient in T/B/NK cells. Without CL pretreatment, human CB-MNCs were removed from SRG rats within 7 hours after transplantation. The rats pretreated with CL could survive after transplantation. Prolonged survival for more than 4 weeks was observed only following a one-time CL injection. Rat macrophages had a species-specific potential for the phagocytosis of human blood cells in vivo. CONCLUSION In human-to-rat HSCT, the short period of early macrophage control, leading to macrophage immunotolerance, is important for engraftment. The generated model can be useful for the creation of future xenotransplantation models or other clinical research.
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Affiliation(s)
- Kinji Furuya
- Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Yun-Wen Zheng
- Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.,Guangdong Provincial Key Laboratory of Large Animal Models for Biomedicine and School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, China.,Institute of Regenerative Medicine and Affiliated Hospital of Jiangsu University, Jiangsu University, Zhenjiang, China.,Department of Regenerative Medicine, School of Medicine, Yokohama City University, Yokohama, Japan
| | - Jian-Yun Ge
- Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.,Guangdong Provincial Key Laboratory of Large Animal Models for Biomedicine and School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, China
| | - Ludi Zhang
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Science, Shanghai, China
| | - Tomoaki Furuta
- Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Chen Liang
- Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Haruna Abe
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Hiroya Yagi
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Hiromi Hamada
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Hiroko Isoda
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Lijian Hui
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Science, Shanghai, China
| | - Nobuhiro Ohkohchi
- Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Tatsuya Oda
- Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
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Rao JS, Matson AW, Taylor RT, Burlak C. Xenotransplantation Literature Update January/February 2021. Xenotransplantation 2021; 28:e12685. [PMID: 33884670 DOI: 10.1111/xen.12685] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Joseph Sushil Rao
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota, Minneapolis, MN, USA.,Solid Organ Transplantation, Department of Surgery, University of Minnesota, Minneapolis, MN, USA
| | - Anders W Matson
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota, Minneapolis, MN, USA
| | - R Travis Taylor
- Department of Medical Microbiology and Immunology, University of Toledo Medical Center, Toledo, OH, USA
| | - Christopher Burlak
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota, Minneapolis, MN, USA
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Hosny N, Matson AW, Kumbha R, Steinhoff M, Sushil Rao J, El-Abaseri TB, Sabek NA, Mahmoud MA, Hering BJ, Burlak C. 3'UTR enhances hCD47 cell surface expression, self-signal function, and reduces ER stress in porcine fibroblasts. Xenotransplantation 2020; 28:e12641. [PMID: 32892439 DOI: 10.1111/xen.12641] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 08/08/2020] [Accepted: 08/17/2020] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Macrophages contribute to xenograft rejection by direct cytotoxicity and by amplifying T cell-mediated immune responses. It has been shown that transgenic expression of hCD47 protects porcine cells from human macrophages by restoring the CD47-SIRPα self-recognition signal. It has also been reported that the long 3' untranslated region (3'UTR) of the hCD47 gene, which is missing from constructs previously used to make hCD47 transgenic pigs, is critical for efficient cell surface expression in human cells. The aim of this study was to investigate the impact of a modified form of the 3'UTR on the expression, localization, and function of hCD47 in transfected porcine cells. METHODS hCD47 constructs with and without the modified 3'UTR were knocked into the GGTA1 locus in porcine fetal fibroblasts using CRISPR. Flow cytometry of the transfected cells was used to analyze hCD47 localization. Endoplasmic reticulum (ER), mitochondrial, and oxidative stress were examined by gene expression analysis and confocal microscopy. Phagocytosis of transfected cells by human macrophages was measured by flow cytometry, and stimulation of human/non-human (NHP) primate lymphocytes by the cells was examined using a PBMCs proliferation assay. RESULTS Cells transfected with the construct lacking the 3'UTR (hCD47(3'UTR-)) exhibited predominantly intracellular expression of hCD47, and showed evidence of ER stress, dysregulated mitochondrial biogenesis, oxidative stress, and autophagy. Inclusion of the 3'UTR (hCD47(3'UTR+)) decreased intracellular expression of hCD47 by 36% and increased cell surface expression by 53%. This was associated with a significant reduction in cellular stress markers and a higher level of protection from phagocytosis by human macrophages. Furthermore, hCD47(3'UTR+) porcine cells stimulated significantly less proliferation of human/NHP T cells than hCD47(3'UTR-) cells. CONCLUSION Our results suggest the potential benefits of using hCD47 constructs containing the 3'UTR to generate genetically engineered hCD47-expressing donor pigs.
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Affiliation(s)
- Nora Hosny
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota School of Medicine, Minneapolis, MN, USA.,Department of Medical Biochemistry and Molecular Biology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Anders W Matson
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota School of Medicine, Minneapolis, MN, USA
| | - Ramesh Kumbha
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota School of Medicine, Minneapolis, MN, USA
| | - Magie Steinhoff
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota School of Medicine, Minneapolis, MN, USA
| | - Joseph Sushil Rao
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota School of Medicine, Minneapolis, MN, USA.,Division of Solid Organ Transplantation, Department of Surgery, University of Minnesota School of Medicine, Minneapolis, MN, USA
| | - Taghrid B El-Abaseri
- Department of Medical Biochemistry and Molecular Biology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Nagwan A Sabek
- Department of Medical Biochemistry and Molecular Biology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Moushira A Mahmoud
- Department of Medical Biochemistry and Molecular Biology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Bernhard J Hering
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota School of Medicine, Minneapolis, MN, USA
| | - Christopher Burlak
- Department of Surgery, Schulze Diabetes Institute, University of Minnesota School of Medicine, Minneapolis, MN, USA
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Shu S, Ren J, Song J. Cardiac xenotransplantation: a promising way to treat advanced heart failure. Heart Fail Rev 2020; 27:71-91. [DOI: 10.1007/s10741-020-09989-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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10
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Lu T, Yang B, Wang R, Qin C. Xenotransplantation: Current Status in Preclinical Research. Front Immunol 2020; 10:3060. [PMID: 32038617 PMCID: PMC6989439 DOI: 10.3389/fimmu.2019.03060] [Citation(s) in RCA: 103] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 12/16/2019] [Indexed: 12/13/2022] Open
Abstract
The increasing life expectancy of humans has led to a growing numbers of patients with chronic diseases and end-stage organ failure. Transplantation is an effective approach for the treatment of end-stage organ failure; however, the imbalance between organ supply and the demand for human organs is a bottleneck for clinical transplantation. Therefore, xenotransplantation might be a promising alternative approach to bridge the gap between the supply and demand of organs, tissues, and cells; however, immunological barriers are limiting factors in clinical xenotransplantation. Thanks to advances in gene-editing tools and immunosuppressive therapy as well as the prolonged xenograft survival time in pig-to-non-human primate models, clinical xenotransplantation has become more viable. In this review, we focus on the evolution and current status of xenotransplantation research, including our current understanding of the immunological mechanisms involved in xenograft rejection, genetically modified pigs used for xenotransplantation, and progress that has been made in developing pig-to-pig-to-non-human primate models. Three main types of rejection can occur after xenotransplantation, which we discuss in detail: (1) hyperacute xenograft rejection, (2) acute humoral xenograft rejection, and (3) acute cellular rejection. Furthermore, in studies on immunological rejection, genetically modified pigs have been generated to bridge cross-species molecular incompatibilities; in the last decade, most advances made in the field of xenotransplantation have resulted from the production of genetically engineered pigs; accordingly, we summarize the genetically modified pigs that are currently available for xenotransplantation. Next, we summarize the longest survival time of solid organs in preclinical models in recent years, including heart, liver, kidney, and lung xenotransplantation. Overall, we conclude that recent achievements and the accumulation of experience in xenotransplantation mean that the first-in-human clinical trial could be possible in the near future. Furthermore, we hope that xenotransplantation and various approaches will be able to collectively solve the problem of human organ shortage.
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Affiliation(s)
- Tianyu Lu
- Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China.,NHC Key Laboratory of Human Disease Comparative Medicine, The Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.,Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, Beijing, China
| | - Bochao Yang
- Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China.,NHC Key Laboratory of Human Disease Comparative Medicine, The Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.,Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, Beijing, China
| | - Ruolin Wang
- Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China.,NHC Key Laboratory of Human Disease Comparative Medicine, The Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.,Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, Beijing, China
| | - Chuan Qin
- Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China.,NHC Key Laboratory of Human Disease Comparative Medicine, The Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.,Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, Beijing, China
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11
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Sykes M. IXA Honorary Member Lecture, 2017: The long and winding road to tolerance. Xenotransplantation 2018; 25:e12419. [PMID: 29913040 DOI: 10.1111/xen.12419] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 05/03/2018] [Indexed: 12/18/2022]
Abstract
The last 15 years or so have seen exciting progress in xenotransplantation, with porcine organ grafts surviving months or even years in non-human primates. These advances reflect the application of new scientific knowledge, improved immunosuppressive agents, and genetic engineering. The field has recently enjoyed a renaissance of interest and hope, largely due to the exponential increase in our capacity to genetically engineer porcine source animals. However, immune responses to xenografts are very powerful and widespread clinical application of xenotransplantation will depend on the ability to suppress these immune responses while preserving the capacity to protect both the recipient and the graft from infectious microorganisms. Our work over the last three decades has aimed to engineer the immune system of the recipient in a manner that achieves specific tolerance to the xenogeneic donor while preserving otherwise normal immune function. Important proofs of principle have been obtained, first in rodents, and later in human immune systems in "humanized mice" and finally in non-human primates, demonstrating the capacity and potential synergy of mixed xenogeneic chimerism and xenogeneic thymic transplantation in tolerizing multiple arms of the immune system. Considering the fact that clinical tolerance has recently been achieved for allografts and the even greater importance of avoiding excessive immunosuppression for xenografts, it is my belief that it is both possible and imperative that we likewise achieve xenograft tolerance. I expect this to be accomplished through the availability of targeted approaches to recipient immune conditioning, understanding of immunological mechanisms of tolerance, advanced knowledge of physiological incompatibilities, and the availability of inbred miniature swine with optimized use of genetic engineering.
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Affiliation(s)
- Megan Sykes
- Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA.,Department of Medicine, Columbia University, New York, NY, USA.,Department of Microbiology & Immunology, Columbia University, New York, NY, USA.,Department of Surgery, Columbia University, New York, NY, USA
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Liu L, He C, Liu J, Lv Z, Wang G, Gao H, Dai Y, Cooper DKC, Cai Z, Mou L. Transplant Tolerance: Current Insights and Strategies for Long-Term Survival of Xenografts. Arch Immunol Ther Exp (Warsz) 2018; 66:355-364. [PMID: 29992337 DOI: 10.1007/s00005-018-0517-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/18/2018] [Indexed: 12/20/2022]
Abstract
Xenotransplantation is an attractive solution to the problem of allograft shortage. However, transplants across discordant species barriers are subject to vigorous immunologic and pathobiologic hurdles, some of which might be overcome with the induction of immunologic tolerance. Several strategies have been designed to induce tolerance to a xenograft at both the central (including induction of mixed chimerism and thymic transplantation) and peripheral (including adoptive transfer of regulatory cells and blocking T cell costimulation) levels. Currently, xenograft tolerance has been well-established in rodent models, but these protocols have not yet achieved similar success in nonhuman primates. This review will discuss the major barriers that impede the establishment of immunological tolerance across xenogeneic barriers and the potential solution to these challenges, and provide a perspective on the future of the development of novel tolerance-inducing strategies.
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Affiliation(s)
- Lu Liu
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center' Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen University School of Medicine, Shenzhen University Health Science Center, Shenzhen, 518035, Guangdong, China.,Department of Gastroenterology' Center For Digestive Diseases, People's Hospital of Baoan District, The 8th people's Hospital of Shenzhen, Shenzhen, 518101, Guangdong, China
| | - Chen He
- Department of Ophthalmology, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen, 518035, Guangdong, China
| | - Jintao Liu
- Department of Gastroenterology' Center For Digestive Diseases, People's Hospital of Baoan District, The 8th people's Hospital of Shenzhen, Shenzhen, 518101, Guangdong, China
| | - Zhiwu Lv
- Department of Gastroenterology' Center For Digestive Diseases, People's Hospital of Baoan District, The 8th people's Hospital of Shenzhen, Shenzhen, 518101, Guangdong, China
| | - Ganlu Wang
- Department of Gastroenterology' Center For Digestive Diseases, People's Hospital of Baoan District, The 8th people's Hospital of Shenzhen, Shenzhen, 518101, Guangdong, China
| | - Hanchao Gao
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center' Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen University School of Medicine, Shenzhen University Health Science Center, Shenzhen, 518035, Guangdong, China
| | - Yifan Dai
- Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - David K C Cooper
- Xenotransplantation Program/Department of Surgery, The University of Alabama at Birmingham, Birmingham, AL, 35233, USA
| | - Zhiming Cai
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center' Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen University School of Medicine, Shenzhen University Health Science Center, Shenzhen, 518035, Guangdong, China
| | - Lisha Mou
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center' Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen University School of Medicine, Shenzhen University Health Science Center, Shenzhen, 518035, Guangdong, China.
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Prolonged Survival of Pig Skin on Baboons After Administration of Pig Cells Expressing Human CD47. Transplantation 2017; 101:316-321. [PMID: 27232934 DOI: 10.1097/tp.0000000000001267] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Successful xenotransplantation will likely depend, in part, on the induction of immunological tolerance, because the high levels of immunosuppression otherwise required would likely have unacceptable side effects. Rapid clearance of administered porcine hematopoietic stem cells by primate macrophages has hampered previous attempts to induce tolerance through mixed hematopoietic chimerism across a pig-to-primate barrier. Phagocytosis is normally inhibited by binding of cell surface protein CD47 to macrophage signal regulatory protein α receptors. However, pig CD47 has previously been shown to be ineffective in transducing signals through primate signal regulatory protein α. METHODS Mobilized peripheral blood hematopoietic cells from transgenic swine expressing high or low levels of human CD47 were infused into conditioned baboons at 3 time points over a 9-week period. Xenogeneic peripheral blood chimerism was assessed after each infusion. Split thickness skin grafts from the hematopoietic cell donor swine were placed on recipients 5 weeks after the last cell infusion and 7 weeks after the discontinuation of all immunosuppression to test immune response. RESULTS The level and duration of transient chimerism were substantially greater in baboons receiving hematopoietic cells from a pig expressing high levels of human CD47. Skin graft survival on high CD47 recipients was prolonged as well, in 1 case showing no signs of rejection at least 53 days after placement. CONCLUSIONS Prolongation of transient porcine chimerism via transgenic expression of human CD47 in a primate model is associated with an immune modulating effect, leading to markedly prolonged survival of donor swine skin xenografts that may be applicable to clinical solid organ xenotransplantation.
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Cooper DKC, Bottino R. Recent advances in understanding xenotransplantation: implications for the clinic. Expert Rev Clin Immunol 2015; 11:1379-90. [PMID: 26548357 PMCID: PMC4879962 DOI: 10.1586/1744666x.2015.1083861] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The results of organ and cell allotransplantation continue to improve, but the field remains limited by a lack of deceased donor organs. Xenotransplantation, for example, between pig and human, offers unlimited organs and cells for clinical transplantation. The immune barriers include a strong innate immune response in addition to the adaptive T-cell response. The innate response has largely been overcome by the transplantation of organs from pigs with genetic modifications that protect their tissues from this response. T-cell-mediated rejection can be controlled by immunosuppressive agents that inhibit costimulation. Coagulation dysfunction between the pig and primate remains problematic but is being overcome by the transplantation of organs from pigs that express human coagulation-regulatory proteins. The remaining barriers will be resolved by the introduction of novel genetically-engineered pigs. Limited clinical trials of pig islet and corneal transplantation are already underway.
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Affiliation(s)
- David K. C. Cooper
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA
| | - Rita Bottino
- Institute of Cellular Therapeutics, Allegheny-Singer Research Institute, Pittsburgh, PA
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15
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Griesemer A, Yamada K, Sykes M. Xenotransplantation: immunological hurdles and progress toward tolerance. Immunol Rev 2015; 258:241-58. [PMID: 24517437 DOI: 10.1111/imr.12152] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The discrepancy between organ need and organ availability represents one of the major limitations in the field of transplantation. One possible solution to this problem is xenotransplantation. Research in this field has identified several obstacles that have so far prevented the successful development of clinical xenotransplantation protocols. The main immunologic barriers include strong T-cell and B-cell responses to solid organ and cellular xenografts. In addition, components of the innate immune system can mediate xenograft rejection. Here, we review these immunologic and physiologic barriers and describe some of the strategies that we and others have developed to overcome them. We also describe the development of two strategies to induce tolerance across the xenogeneic barrier, namely thymus transplantation and mixed chimerism, from their inception in rodent models through their current progress in preclinical large animal models. We believe that the addition of further beneficial transgenes to Gal knockout swine, combined with new therapies such as Treg administration, will allow for successful clinical application of xenotransplantation.
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Affiliation(s)
- Adam Griesemer
- Columbia Center for Translational Immunology, Columbia University College of Physicians and Surgeons, New York, NY, USA
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16
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Tena A, Kurtz J, Leonard DA, Dobrinsky JR, Terlouw SL, Mtango N, Verstegen J, Germana S, Mallard C, Arn JS, Sachs DH, Hawley RJ. Transgenic expression of human CD47 markedly increases engraftment in a murine model of pig-to-human hematopoietic cell transplantation. Am J Transplant 2014; 14:2713-22. [PMID: 25278264 PMCID: PMC4236244 DOI: 10.1111/ajt.12918] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 06/16/2014] [Accepted: 07/06/2014] [Indexed: 01/25/2023]
Abstract
Mixed chimerism approaches for induction of tolerance of solid organ transplants have been applied successfully in animal models and in the clinic. However, in xenogeneic models (pig-to-primate), host macrophages participate in the rapid clearance of porcine hematopoietic progenitor cells, hindering the ability to achieve mixed chimerism. CD47 is a cell-surface molecule that interacts in a species-specific manner with SIRPα receptors on macrophages to inhibit phagocytosis and expression of human CD47 (hCD47) on porcine cells has been shown to inhibit phagocytosis by primate macrophages. We report here the generation of hCD47 transgenic GalT-KO miniature swine that express hCD47 in all blood cell lineages. The effect of hCD47 expression on xenogeneic hematopoietic engraftment was tested in an in vivo mouse model of human hematopoietic cell engraftment. High-level porcine chimerism was observed in the bone marrow of hCD47 progenitor cell recipients and smaller but readily measurable chimerism levels were observed in the peripheral blood of these recipients. In contrast, transplantation of WT progenitor cells resulted in little or no bone marrow engraftment and no detectable peripheral chimerism. These results demonstrate a substantial protective effect of hCD47 expression on engraftment and persistence of porcine cells in this model, presumably by modulation of macrophage phagocytosis.
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Affiliation(s)
- Aseda Tena
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
| | - Josef Kurtz
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA,Department of Biology, Emmanuel College, Boston, MA
| | - David A. Leonard
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
| | | | | | | | | | - Sharon Germana
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
| | - Christopher Mallard
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
| | - J. Scott Arn
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
| | - David H. Sachs
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
| | - Robert J. Hawley
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
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Boksa M, Zeyland J, Słomski R, Lipiński D. Immune modulation in xenotransplantation. Arch Immunol Ther Exp (Warsz) 2014; 63:181-92. [PMID: 25354539 PMCID: PMC4429136 DOI: 10.1007/s00005-014-0317-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 07/22/2014] [Indexed: 01/17/2023]
Abstract
The use of animals as donors of tissues and organs for xenotransplantations may help in meeting the increasing demand for organs for human transplantations. Clinical studies indicate that the domestic pig best satisfies the criteria of organ suitability for xenotransplantation. However, the considerable phylogenetic distance between humans and the pig causes tremendous immunological problems after transplantation, thus genetic modifications need to be introduced to the porcine genome, with the aim of reducing xenotransplant immunogenicity. Advances in genetic engineering have facilitated the incorporation of human genes regulating the complement into the porcine genome, knockout of the gene encoding the formation of the Gal antigen (α1,3-galactosyltransferase) or modification of surface proteins in donor cells. The next step is two-fold. Firstly, to inhibit processes of cell-mediated xenograft rejection, involving natural killer cells and macrophages. Secondly, to inhibit rejection caused by the incompatibility of proteins participating in the regulation of the coagulation system, which leads to a disruption of the equilibrium in pro- and anti-coagulant activity. Only a simultaneous incorporation of several gene constructs will make it possible to produce multitransgenic animals whose organs, when transplanted to human recipients, would be resistant to hyperacute and delayed xenograft rejection.
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Affiliation(s)
- Magdalena Boksa
- Department of Biochemistry and Biotechnology, Poznań University of Life Sciences, Dojazd 11, 60-632, Poznań, Poland,
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Maeda A, Kawamura T, Ueno T, Usui N, Eguchi H, Miyagawa S. The suppression of inflammatory macrophage-mediated cytotoxicity and proinflammatory cytokine production by transgenic expression of HLA-E. Transpl Immunol 2013; 29:76-81. [PMID: 23994719 DOI: 10.1016/j.trim.2013.08.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2013] [Revised: 08/09/2013] [Accepted: 08/11/2013] [Indexed: 12/31/2022]
Abstract
BACKGROUND Macrophages participate in xenogenic rejection and represent a major biological obstacle to successful xenotransplantation. The signal inhibitory regulatory protein α (SIRPα) receptor was reported to be a negative regulator of macrophage phagocytic activity via interaction with CD47, its ligand. Because a majority of human macrophages express the inhibitory receptor CD94/NKG2A, which binds specifically to the human leukocyte antigen (HLA)-E and contains immunoreceptor tyrosine-based inhibition motifs (ITIMs), the inhibitory function of HLA class I molecules, HLA-E, on macrophage-mediated cytolysis was examined. The suppressive effect against proinflammatory cytokine production by macrophages was also examined. METHODS Complementary DNA (cDNA) of HLA-E, and CD47 were prepared and transfected into swine endothelial cells (SEC). The expression of the modified genes was evaluated by flow cytometry and macrophage-mediated cytolysis was assessed using in vitro generated macrophages. RESULTS Transgenic expression of HLA-E significantly suppressed the macrophage-mediated cytotoxicity. HLA-E transgenic expression demonstrated a significant suppression equivalent to CD47 transgenic expression. Furthermore, transgenic HLA-E suppressed the production of pro-inflammatory cytokines by inflammatory macrophages. CONCLUSIONS These results indicate that generating transgenic HLA-E pigs might protect porcine grafts from, not only NK cytotoxicity, but also macrophage-mediated cytotoxicity.
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Affiliation(s)
- Akira Maeda
- Department of Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
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19
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del Rio ML, Seebach JD, Fernández-Renedo C, Rodriguez-Barbosa JI. ITIM-dependent negative signaling pathways for the control of cell-mediated xenogeneic immune responses. Xenotransplantation 2013; 20:397-406. [PMID: 23968542 DOI: 10.1111/xen.12049] [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: 05/29/2013] [Accepted: 07/31/2013] [Indexed: 12/24/2022]
Abstract
Xenotransplantation is an innovative field of research with the potential to provide us with an alternative source of organs to face the severe shortage of human organ donors. For several reasons, pigs have been chosen as the most suitable source of organs and tissues for transplantation in humans. However, porcine xenografts undergo cellular immune responses representing a major barrier to their acceptance and normal functioning. Innate and adaptive xenogeneic immunity is mediated by both the recognition of xenogeneic tissue antigens and the lack of inhibition due to molecular cross-species incompatibilities of regulatory pathways. Therefore, the delivery of immunoreceptor tyrosine-based inhibitory motif (ITIM)-dependent and related negative signals to control innate (NK cells, macrophages) and adaptive T and B cells might overcome cell-mediated xenogeneic immunity. The proof of this concept has already been achieved in vitro by the transgenic overexpression of human ligands of several inhibitory receptors in porcine cells resulting in their resistance against xenoreactivity. Consequently, several transgenic pigs expressing tissue-specific human ligands of inhibitory coreceptors (HLA-E, CD47) or soluble competitors of costimulation (belatacept) have already been generated. The development of these robust and innovative approaches to modulate human anti-pig cellular immune responses, complementary to conventional immunosuppression, will help to achieve long-term xenograft survival. In this review, we will focus on the current strategies to enhance negative signaling pathways for the regulation of undesirable cell-mediated xenoreactive immune responses.
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Affiliation(s)
- Maria-Luisa del Rio
- Transplantation Immunobiology Section, Institute of Biomedicine, University of Leon, Leon, Spain; Leon University Hospital, Castilla and Leon Transplantation Regional Agency, Leon, Spain
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20
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Brock LG, Delputte PL, Waldman JP, Nauwynck HJ, Rees MA. Porcine sialoadhesin: a newly identified xenogeneic innate immune receptor. Am J Transplant 2012; 12:3272-82. [PMID: 22958948 PMCID: PMC3513673 DOI: 10.1111/j.1600-6143.2012.04247.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Extracorporeal porcine liver perfusion is being developed as a bridge to liver allotransplantation for patients with fulminant hepatic failure. This strategy is limited by porcine Kupffer cell destruction of human erythrocytes, mediated by lectin binding of a sialic acid motif in the absence of antibody and complement. Sialoadhesin, a macrophage restricted lectin that binds sialic acid, was originally described as a sheep erythrocyte binding receptor. Given similarities between sialoadhesin and the unidentified macrophage lectin in our model, we hypothesized porcine sialoadhesin contributed to recognition of human erythrocytes. Two additional types of macrophages were identified to bind human erythrocytes-spleen and alveolar. Expression of sialoadhesin was confirmed by immunofluorescence in porcine tissues and by flow cytometry on primary macrophages. A stable transgenic cell line expressing porcine sialoadhesin (pSn CHO) bound human erythrocytes, while a sialoadhesin mutant cell line did not. Porcine macrophage and pSn CHO recognition of human erythrocytes was inhibited approximately 90% by an antiporcine sialoadhesin monoclonal antibody and by human erythrocyte glycoproteins. Furthermore, this binding was substantially reduced by sialidase treatment of erythrocytes. These data support the hypothesis that porcine sialoadhesin is a xenogeneic receptor that mediates porcine macrophage binding of human erythrocytes in a sialic acid-dependent manner.
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Affiliation(s)
- Linda G. Brock
- Department of Urology, University of Toledo Health Sciences Campus, Toledo, OH USA
| | - Peter L. Delputte
- Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Joshua P. Waldman
- Department of Urology, University of Toledo Health Sciences Campus, Toledo, OH USA
| | - Hans J. Nauwynck
- Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Michael A. Rees
- Department of Urology, University of Toledo Health Sciences Campus, Toledo, OH USA
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Scalea J, Hanecamp I, Robson SC, Yamada K. T-cell-mediated immunological barriers to xenotransplantation. Xenotransplantation 2012; 19:23-30. [PMID: 22360750 DOI: 10.1111/j.1399-3089.2011.00687.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Xenotransplantion remains the most viable option for significant expansion of the donor organ pool in clinical transplantation. With the advent of nuclear transfer technologies, the production of transgenic swine has become a possibility. These animals have allowed transplant investigators to overcome humoral mechanisms of hyperacute xenograft rejection in experimental pig-to-non-human primate models. However, other immunologic barriers preclude long-term acceptance of xenografts. This review article focuses on a major feature of xenogeneic rejection: xenogeneic T cell responses. Evidence obtained from both small and large animal models, particularly those using either islet cells or kidneys, have demonstrated that T cell responses play a major role in xenogeneic rejection, and that immunosuppression alone is likely incapable of completely suppressing these responses. Additionally, both the direct and indirect pathway of antigen presentation appear to be involved in these anti donor processes. Enhanced understanding of (i) CD47 and its role in transduced xeno-bone marrow (ii) CD39 and its role in coagulation dysregulation and (iii) thymic transplantation have provided us with encouraging results. Presently, experiments evaluating the possibility of xenogeneic tolerance are underway.
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Affiliation(s)
- Joseph Scalea
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA 02129, USA
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22
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Abstract
PURPOSE OF REVIEW This review assesses the recent progress in xenograft rejection by innate immune responses, with a focus on innate cellular xenoreactivity. RECENT FINDINGS Current literature was reviewed for new insights into the role of innate cellular immunity in xenograft rejection. Increasing evidence confirms that vigorous innate immune cell activation is accounted for by a combination of xenoantigen recognition by activating receptors, and incompatibility in inhibitory receptor-ligand interactions. Although both innate humoral and cellular xenoimmune responses are predominantly elicited by preformed and induced xenoreactive antibodies in nonhuman primates following porcine xenotransplantation, innate immune cells can also be activated by xenografts in the absence of antibodies. The latter antibody-independent response will likely persist in recipients even when adaptive xenoimmune responses are suppressed. In addition to xenograft rejection by recipient innate immune cells, phagocytic cells within liver xenografts are also deleterious to recipients by causing thrombocytopenia. SUMMARY Strategies of overcoming innate immune responses are required for successful clinical xenotransplantation. In addition to developing better immunosuppressive and tolerance induction protocols, endeavors towards further genetic modifications of porcine source animals are ultimately important for successful clinical xenotransplantation.
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Affiliation(s)
- Hui Wang
- Columbia Center for Translational Immunology, Columbia University College of Physicians and Surgeons, New York 10032, USA
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Wang C, Wang H, Ide K, Wang Y, Van Rooijen N, Ohdan H, Yang YG. Human CD47 expression permits survival of porcine cells in immunodeficient mice that express SIRPα capable of binding to human CD47. Cell Transplant 2011; 20:1915-20. [PMID: 21535911 DOI: 10.3727/096368911x566253] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Signal regulatory protein α (SIRPα) is a critical immune inhibitory receptor on macrophages, and its interaction with CD47 prevents autologous phagocytosis. We have previously shown that pig CD47 does not interact with human SIRPα, and that human CD47 expression inhibits phagocytosis of porcine cells by human macrophages in vitro. In this study, we have investigated the potential of human CD47 expression to promote porcine cell survival in vivo. Human CD47-expressing and control porcine B-lymphoma cells were transplanted into T- and B-cell-deficient nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice that express SIRPα capable of interacting with human CD47. Only the human CD47-expressing porcine lymphoma cells survived and were able to form tumors in NOD/SCID mice; however, both the control and human CD47-expressing porcine cells survived in macrophage-depleted NOD/SCID mice. These results indicate that transgenic expression of human CD47 may provide an effective approach to inhibiting macrophage-mediated xenograft rejection in clinical xenotransplantation.
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Affiliation(s)
- Chunfeng Wang
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, China
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Abstract
Robust immune responses to xenografts remain a major obstacle to clinical translation of xenotransplantation, which could otherwise be a potential solution to the worldwide shortage of organ donors. The more vigorous xenograft rejection relative to allograft rejection is largely accounted for by the extensive genetic disparities between the donor and recipient. Xenografts activate host immunity not only by expressing immunogenic xenoantigens that provide the targets for immune recognition and rejection, but also by lacking ligands for the host immune inhibitory receptors. This review is focused on recent findings regarding the role of CD47, a ligand of an immune inhibitory receptor SIRPalpha, in xenograft rejection and induction of xenotolerance.
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Affiliation(s)
- Yong-Guang Yang
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
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25
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Cooper DK, Hara H, Yazer M. Genetically Engineered Pigs as a Source for Clinical Red Blood Cell Transfusion. Clin Lab Med 2010; 30:365-80. [DOI: 10.1016/j.cll.2010.02.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Long C, Hara H, Pawlikowski Z, Koike N, d'Arville T, Yeh P, Ezzelarab M, Ayares D, Yazer M, Cooper DKC. Genetically engineered pig red blood cells for clinical transfusion: initial in vitro studies. Transfusion 2009; 49:2418-29. [PMID: 19624491 DOI: 10.1111/j.1537-2995.2009.02306.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Pigs are a potential source of red blood cells (RBCs) and could resolve the shortage of human blood for transfusion. This study investigated in vitro the compatibility of genetically engineered pig RBCs (pRBCs) with the human innate immune response. STUDY DESIGN AND METHODS Human volunteers of all ABO blood types were sources of sera and those of O blood type were sources of circulating monocytes/macrophages. RBCs from ABO-compatible (ABO-C) and ABO-incompatible (ABO-I) humans and wild-type (WT) and alpha-1,3-galactosyltransferase gene-knockout (GTKO) pigs were tested for hemagglutination, immunoglobulin (Ig)M/IgG antibody binding, and complement-dependent cytotoxicity (CDC) using human sera. Phagocytosis of RBCs by human monocyte-derived macrophages was measured by coculture in the absence or presence of pooled human O serum. RESULTS RBCs showed significant differences (p < 0.01) with regard to hemagglutination, IgM and IgG binding, and CDC (ABO-C < GTKO < ABO-I < WT). In the absence of pooled human O serum (antibodies), there was no phagocytosis of any RBCs; in the presence of serum (antibodies), phagocytosis of ABO-I RBCs was greater than of WT (p < 0.01), which in turn was greater than of GTKO RBCs (p < 0.05). CONCLUSIONS GTKO RBCs were significantly more compatible than ABO-I and WT RBCs, but were not comparable to ABO-C combinations. In the presence of antibody, human monocyte-derived macrophages phagocytosed ABO-I RBC/sera combinations more efficiently than pRBCs. These observations contribute to our ultimate goal of using genetically engineered pRBCs for clinical blood transfusion. However, pigs will require other modifications or manipulations if they are to become suitable for human transfusion.
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Affiliation(s)
- Cassandra Long
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Starzl Biomedical Science Tower, W1540, 200 Lothrop Street, Pittsburgh, PA 15261, USA
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Cadili A, Kneteman N. The role of macrophages in xenograft rejection. Transplant Proc 2009; 40:3289-93. [PMID: 19100374 DOI: 10.1016/j.transproceed.2008.08.125] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2008] [Accepted: 08/29/2008] [Indexed: 11/25/2022]
Abstract
Safe and effective xenotransplantation would provide a valuable answer to many of the limitations of allogenic transplantation. Such limitations include scarcity of organ supply and morbidity to donors in cases of living-related donor transplantation. The main hurdle to the efficacious application of xenotransplantation in clinical medicine is the fierce host immune response to xenografts. This immune response is embodied in 3 different types of xenograft rejection. Both hyperacute rejection and delayed xenograft rejection are mediated by natural antibodies and are concerned primarily with whole organ rejection. Cellular xenograft rejection (CXR), on the other hand, is concerned with both whole organ and CXR and is mediated by innate immunity rather than natural antibodies. Macrophages, which are cells of the innate immune system, play a role in all 3 types of xenograft rejection (not just CXR). They impart their effects both directly and through T-cell activation.
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Affiliation(s)
- A Cadili
- Department of Surgery, University of Alberta, Edmonton, Alberta, Canada
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28
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Xenotransplantation: role of natural immunity. Transpl Immunol 2008; 21:70-4. [PMID: 18992342 DOI: 10.1016/j.trim.2008.10.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2008] [Accepted: 10/09/2008] [Indexed: 11/20/2022]
Abstract
Hyperacute rejection, mediated by natural anti-Galalpha1,3Galbeta1,4GlcNAc (alphaGal) antibodies and the classically activated complement pathway, was identified as the first major barrier to the survival of porcine organs in humans. Subsequently, discordant pig-to-nonhuman primate and concordant rodent models revealed key roles for T and B lymphocytes in the second form of rejection, acute vascular rejection (AVR) or delayed xenograft rejection (DXR). As significant progress was made in strategies to circumvent or suppress xenoreactivity of the adaptive immune system, it became clear that, apart from natural antibodies, other innate immune system elements actively participate in AVR/DXR and represent a barrier to xenograft acceptance that may be particularly difficult to overcome. Observations in pig-to-primate and semi-discordant and concordant rodent models indicate that Natural Killer (NK) cells play a more prominent role in xenograft than in allograft rejection. Several mechanisms through which human NK cells recognize porcine endothelial cells have been elucidated and these appear to be more diverse than those involved in NK cell alloreactivity. Further, it has been demonstrated that human macrophages and neutrophils can directly recognize pig derived cells and can mediate direct xenograft damage. Here, we review the recent progress in the understanding of the xenoreactivity of the natural immune system, focussing on preclinical pig-to-(non)human primate systems, and discuss the proposed strategies to overcome these barriers.
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Hara H, Gridelli B, Lin YJ, Marcos A, Cooper DKC. Liver xenografts for the treatment of acute liver failure: clinical and experimental experience and remaining immunologic barriers. Liver Transpl 2008; 14:425-34. [PMID: 18383106 DOI: 10.1002/lt.21476] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A critical element restricting the application of liver transplantation is the shortage of human deceased donor organs. Xenotransplantation using pig organs might be a solution to this shortage. Although the problems that still require resolution include the immunologic barrier, the potential risk of transferring infectious agents with the transplanted organ, and uncertainty about whether the transplanted organ will function satisfactorily in the human environment, recent progress in the genetic manipulation of pigs has led to the prospect that clinical xenografting, at least as a bridge to allotransplantation, may be possible in the foreseeable future. Experience with clinical auxiliary and orthotopic liver xenotransplantation and experimental liver xenotransplantation in nonhuman primate and other large animal models is reviewed, and the remaining immunologic problems are discussed. Evidence suggests that, in patients with hepatic failure, the pig liver may be less susceptible to antibody-mediated injury than other pig organs, such as the heart or kidney. Pig Kupffer cells and other macrophages will recognize and phagocytose primate red blood cells, but this problem should be overcome by pretransplant depletion of macrophages from the organ-source pig. From the evidence currently available, it does not seem unduly optimistic to anticipate that a liver from an alpha1,3-galactosyltransferase gene-knockout pig would survive at least long enough to function as a successful bridge to allotransplantation.
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Affiliation(s)
- Hidetaka Hara
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA 15261, USA
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Sykes M. 2007 IXA Presidential Address. Progress toward an ideal source animal: opportunities and challenges in a changing world. Xenotransplantation 2008; 15:7-13. [DOI: 10.1111/j.1399-3089.2008.00441.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Wang H, Madariaga ML, Wang S, Van Rooijen N, Oldenborg PA, Yang YG. Lack of CD47 on nonhematopoietic cells induces split macrophage tolerance to CD47null cells. Proc Natl Acad Sci U S A 2007; 104:13744-9. [PMID: 17699632 PMCID: PMC1949343 DOI: 10.1073/pnas.0702881104] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2007] [Indexed: 12/25/2022] Open
Abstract
Macrophages recognize CD47 as a marker of "self" and phagocytose CD47(null) hematopoietic cells. Using CD47 chimera models, here, we show that the phagocytic activity of macrophages against CD47(null) hematopoietic cells is conferred by CD47 expression on nonhematopoietic cells, and this "education" process is hematopoietic cell-independent. Macrophages in the chimeras where nonhematopoietic cells express CD47 phagocytose CD47(null) cells, whereas those in the chimeras lacking CD47 on nonhematopoietic cells are tolerant to CD47(null) cells. However, macrophages in the latter chimeras retain phagocytic activity against CD47(null) RBCs, demonstrating a split macrophage tolerance to CD47(null) hematopoietic cells. The findings highlight the potential importance of nonhematopoietic cells in the regulation of macrophage function, and suggest a previously uncharacterized mechanism of macrophage tolerance.
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Affiliation(s)
- Hui Wang
- *Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129
| | - Maria Lucia Madariaga
- *Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129
| | - Shumei Wang
- *Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129
| | - Nico Van Rooijen
- Department of Molecular Cell Biology, Faculty of Medicine, Vrije Universiteit, VUMC, Van der Boechorstraat 7, 1081 BT, Amsterdam, The Netherlands; and
| | - Per-Arne Oldenborg
- Department of Integrative Medical Biology, Section for Histology and Cell Biology, Umeå University, SE-901 87 Umeå, Sweden
| | - Yong-Guang Yang
- *Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129
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Yang YG, Sykes M. Xenotransplantation: current status and a perspective on the future. Nat Rev Immunol 2007; 7:519-31. [PMID: 17571072 DOI: 10.1038/nri2099] [Citation(s) in RCA: 231] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Xenotransplantation using pigs as the transplant source has the potential to resolve the severe shortage of human organ donors. Although the development of relatively non-toxic immunosuppressive or tolerance-inducing regimens will be required to justify clinical trials using pig organs, recent advances in our understanding of the biology of xenograft rejection and zoonotic infections, and the generation of alpha1,3-galactosyltransferase-deficient pigs have moved this approach closer to clinical application. This Review highlights the major obstacles impeding the translation of xenotransplantation into clinical therapies and the potential solutions, providing a perspective on the future of clinical xenotransplantation.
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Affiliation(s)
- Yong-Guang Yang
- Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02129, USA
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Ide K, Wang H, Tahara H, Liu J, Wang X, Asahara T, Sykes M, Yang YG, Ohdan H. Role for CD47-SIRPalpha signaling in xenograft rejection by macrophages. Proc Natl Acad Sci U S A 2007; 104:5062-6. [PMID: 17360380 PMCID: PMC1829264 DOI: 10.1073/pnas.0609661104] [Citation(s) in RCA: 228] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
We have previously proven that human macrophages can phagocytose porcine cells even in the absence of Ab or complement opsonization, indicating that macrophages present a pivotal immunological obstacle to xenotransplantation. A recent report indicates that the signal regulatory protein (SIRP)alpha is a critical immune inhibitory receptor on macrophages, and its interaction with CD47, a ligand for SIRPalpha, prevents autologous phagocytosis. Considering the limited compatibility (73%) in amino acid sequences between pig and human CD47, we hypothesized that the interspecies incompatibility of CD47 may contribute to the rejection of xenogeneic cells by macrophages. In the present study, we have demonstrated that porcine CD47 does not induce SIRPalpha tyrosine phosphorylation in human macrophage-like cell line, and soluble human CD47-Fc fusion protein inhibits the phagocytic activity of human macrophages toward porcine cells. In addition, we have verified that manipulation of porcine cells for expression of human CD47 radically reduces the susceptibility of the cells to phagocytosis by human macrophages. These results indicate that the interspecies incompatibility of CD47 significantly contributes to the rejection of xenogeneic cells by macrophages. Genetic induction of human CD47 on porcine cells could provide inhibitory signaling to SIRPalpha on human macrophages, providing a novel approach to preventing macrophage-mediated xenograft rejection.
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Affiliation(s)
- Kentaro Ide
- *Department of Surgery, Division of Frontier Medical Science, Programs for Biomedical Research, Graduate School of Biomedical Science, Hiroshima University, Hiroshima 734-8551, Japan
| | - Hui Wang
- Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129; and
| | - Hiroyuki Tahara
- *Department of Surgery, Division of Frontier Medical Science, Programs for Biomedical Research, Graduate School of Biomedical Science, Hiroshima University, Hiroshima 734-8551, Japan
| | - Jianxiang Liu
- Neuroprotection Research Laboratory, Department of Radiology and Neurology, Massachusetts General Hospital, and Program in Neuroscience, Harvard Medical School, Boston, MA 02129
| | - Xiaoying Wang
- Neuroprotection Research Laboratory, Department of Radiology and Neurology, Massachusetts General Hospital, and Program in Neuroscience, Harvard Medical School, Boston, MA 02129
| | - Toshimasa Asahara
- *Department of Surgery, Division of Frontier Medical Science, Programs for Biomedical Research, Graduate School of Biomedical Science, Hiroshima University, Hiroshima 734-8551, Japan
| | - Megan Sykes
- Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129; and
| | - Yong-Guang Yang
- Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129; and
- To whom correspondence may be addressed at:
Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Massachusetts General Hospital-East, Building 149, 13th Street, Boston, MA 02129. E-mail:
| | - Hideki Ohdan
- *Department of Surgery, Division of Frontier Medical Science, Programs for Biomedical Research, Graduate School of Biomedical Science, Hiroshima University, Hiroshima 734-8551, Japan
- To whom correspondence may be addressed at:
Department of Surgery, Division of Frontier Medical Science, Programs for Biomedical Research, Graduate School of Biomedical Science, Hiroshima University, 1-2-3 Kasumi, Minami-Ku, Hiroshima 734-8551, Japan. E-mail:
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Wang H, VerHalen J, Madariaga ML, Xiang S, Wang S, Lan P, Oldenborg PA, Sykes M, Yang YG. Attenuation of phagocytosis of xenogeneic cells by manipulating CD47. Blood 2006; 109:836-42. [PMID: 17008545 PMCID: PMC1785095 DOI: 10.1182/blood-2006-04-019794] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Signal regulatory protein alpha (SIRPalpha) is a critical immune inhibitory receptor on macrophages, and its interaction with CD47, a ligand for SIRPalpha, prevents autologous phagocytosis. We hypothesized that interspecies incompatibility of CD47 may contribute to the rejection of xenogeneic cells by macrophages. Here, we show that pig CD47 does not interact with mouse SIPRalpha. Similar to CD47-/- mouse cells, porcine red blood cells (RBCs) failed to induce SIRPalpha tyrosine phosphorylation in mouse macrophages. Blocking SIRPalpha with antimouse SIRPalpha mAb (P84) significantly enhanced the phagocytosis of CD47+/+ mouse cells, but did not affect the engulfment of porcine or CD47-/- mouse cells by mouse macrophages. CD47-deficient mice, whose macrophages do not phagocytose CD47-/- mouse cells, showed markedly delayed clearance of porcine RBCs compared with wild-type mouse recipients. Furthermore, mouse CD47 expression on porcine cells markedly reduced their phagocytosis by mouse macrophages both in vitro and in vivo. These results indicate that interspecies incompatibility of CD47 contributes significantly to phagocytosis of xenogeneic cells by macrophages and suggest that genetic manipulation of donor CD47 to improve its interaction with the recipient SIRPalpha may provide a novel approach to prevent phagocyte-mediated xenograft rejection.
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Affiliation(s)
- Hui Wang
- Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA
- Wenzhou Medical College, Wenzhou, China
| | - Jon VerHalen
- Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Maria Lucia Madariaga
- Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Shuanglin Xiang
- Beth Israel Deaconess Medical Center of Harvard Medical School, Boston, MA
| | - Shumei Wang
- Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Ping Lan
- Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Per-Arne Oldenborg
- Department of Integrative Medical Biology, Section for Histology and Cell Biology, Umeå University, Umeå, Sweden
| | - Megan Sykes
- Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Yong-Guang Yang
- Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA
- Wenzhou Medical College, Wenzhou, China
- Correspondence: Yong-Guang Yang,
Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, MGH-East, Bldg 149-5102, 13th St, Boston, MA 02129; e-mail:
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Affiliation(s)
- Michael A Rees
- Department of Urology, Medical College of Ohio, Toledo, USA.
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Tseng YL, Dor FJMF, Kuwaki K, Ryan D, Wood J, Denaro M, Giovino M, Yamada K, Hawley R, Patience C, Schuurman HJ, Awwad M, Sachs DH, Cooper DKC. Bone marrow transplantation from alpha1,3-galactosyltransferase gene-knockout pigs in baboons. Xenotransplantation 2005; 11:361-70. [PMID: 15196131 DOI: 10.1111/j.1399-3089.2004.00151.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Successful hematopoietic cell allotransplantation results in donor-specific tolerance, but this approach has been unsuccessful in the wild-type pig-to-baboon xenotransplantation model, as pig cells were lost from the circulation within 5 days. However, after cessation of immunosuppressive therapy on day 28, all baboons demonstrated non-specific unresponsiveness on mixed leukocyte reaction (MLR) for at least 30 days. We have now investigated the transplantation of bone marrow (BM) cells from miniature swine homozygous for alpha1,3-galactosyltransferase gene-knockout (GalT-KO). METHODS Baboons (n = 3) were pre-treated with whole body and thymic irradiation, anti-thymocyte globulin, and splenectomy, and received immunosuppressive and supportive therapy for 28 days. BM was harvested from GalT-KO swine (n = 3). The baboons were monitored for the presence of pig cells by flow cytometry and colony-forming units (CFUs), and for cellular reactivity by MLR. RESULTS A mean of 11 x 10(8) BM cells/kg was infused into each baboon. The mean absolute numbers and percentages of pig cells detected in the blood at 2 h and on days 1, 2 and 4, respectively, were 641/microl (9.5%), 132/microl (3.4%), 242/microl (3.9%), and 156/microl (2.9%). One baboon died (from accidental hemorrhage) on day 6, at which time chimerism was present in the blood (2.0%) and BM (6.4%); pig cell engraftment in the BM was confirmed by polymerase chain reaction (PCR) of CFUs. In the two other baboons, blood chimerism was lost after day 5 but returned at low levels (<1%) between days 9 to 16 and 7 to 17, respectively, indicating transient BM engraftment. Both surviving baboons showed non-specific unresponsiveness on MLR until they were euthanized on days 85 and 110, respectively. CONCLUSIONS By using BM cells from GalT-KO pigs, chimerism was detected at levels comparable with previous studies when 30-fold more growth factor-mobilized peripheral blood progenitor cells had been transplanted. In addition, cellular hyporesponsiveness was prolonged. However, long-term engraftment and chimerism were not achieved.
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Affiliation(s)
- Y-L Tseng
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02129, USA
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Tseng YL, Tseng YL, Sachs DH, Cooper DKC. Porcine Hematopoietic Progenitor Cell Transplantation in Nonhuman Primates: A Review of Progress. Transplantation 2005; 79:1-9. [PMID: 15714161 DOI: 10.1097/01.tp.0000146504.73727.13] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The critical shortage of human donor organs for transplantation would be overcome if a suitable animal, e.g., the pig, could be used as an organ source. There are, however, several immune barriers that have to date resulted in limited function of pig organs transplanted into nonhuman primates. It would be beneficial, and indeed may be essential, to induce a state of tolerance in the primate recipient to the pig organ. In allotransplantation, the successful transplantation of hematopoietic progenitor cells with the development of mixed chimerism is associated with the induction of tolerance toward a donor-specific organ. For some years, this approach has been explored in the pig-to-nonhuman primate model. This experience is briefly reviewed. The problems of natural and elicited anti-pig antibodies, recipient platelet adhesion to pig hematopietic progenitor cells, and the rapid removal of these cells by the host macrophage-phagocytic system are highlighted. Recent experience with the use of hematopoietic cells from pigs homozygous for alpha1,3-galactosyltransferase gene-knockout is reported.
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Affiliation(s)
- Yau-Lin Tseng
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02129, USA
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Dor FJMF, Tseng YL, Kuwaki K, Ko DSC, Cooper DKC. Pig spleen transplantation induces transient hematopoietic cell chimerism in baboons. Xenotransplantation 2004; 11:298-300. [PMID: 15099211 DOI: 10.1111/j.1399-3089.2004.00131.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Yang YG. Application of xenogeneic stem cells for induction of transplantation tolerance: present state and future directions. ACTA ACUST UNITED AC 2004; 26:187-200. [PMID: 15378269 DOI: 10.1007/s00281-004-0159-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2004] [Accepted: 04/18/2004] [Indexed: 01/22/2023]
Abstract
Xenotransplantation using pig organs provides a possible solution to the severe shortage of allogeneic organ donors, one of the major limiting factors in clinical transplantation. However, because of the greater antigenic differences that exist between different species than within a species, the immune response to xenografts is much more vigorous than to allografts. Thus, tolerance induction is essential to the success of clinical xenotransplantation. Tolerance induced by mixed hematopoietic chimerism across the MHC barrier is remarkably robust, but its ability to induce tolerance across highly disparate xenogeneic barriers remains poorly studied. None of the current available regimens of host conditioning, which permit hematopoietic stem cell engraftment and chimerism induction in allogeneic or closely related (concordant) xenogeneic combinations, has been demonstrated to be effective in establishing porcine hematopoietic chimerism in a discordant xenogeneic species. Unlike bone marrow transplantation within the same species, the innate immune system and the species specificity of cytokines and adhesion molecules essential to hematopoiesis pose formidable obstacles to the establishment of donor hematopoiesis across discordant xenogeneic barriers. The genetic incompatibility between species may also impede xenograft tolerance induction by mixed chimerism. While we remain far from achieving tolerance in clinical xenotransplantation, recent studies using a transgenic mouse model have proven the principle that mixed hematopoietic chimerism may induce mouse and human T cell tolerance to porcine xenografts. This review article focuses on the barriers to porcine hematopoietic engraftment in highly disparate xenogeneic species and the possible application of mixed hematopoietic chimerism to xenograft tolerance induction.
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Affiliation(s)
- Yong-Guang Yang
- Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, MGH-East, Building 149, 13th Street, Boston, MA 02129, USA.
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Rouhani FJ, Dor FJMF, Cooper DKC. Investigation of red blood cells from α1,3-galactosyltransferase-knockout pigs for human blood transfusion. Transfusion 2004; 44:1004-12. [PMID: 15225240 DOI: 10.1111/j.1537-2995.2004.04002.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Pigs are a potential source of red blood cells (RBCs) for transfusion into humans, but the presence of galactose-alpha1,3-galactose (Gal) epitopes on their surface, against which humans have anti-Gal, has been perceived as a major barrier. alpha1,3-Galactosyltransferase gene-knockout pigs, which do not express Gal epitopes on RBCs (Gal-/-), have recently become available. STUDY DESIGN AND METHODS In vitro, RBCs from Gal-/- pigs were exposed to sera from naïve humans or baboons or from baboons previously sensitized to pig antigens; immunoglobulin binding was measured by flow cytometry, and cytotoxicity, by a hemolytic assay. In vivo, relatively small numbers of Gal-/- RBCs were transfused into two nonsensitized untreated baboons. The survival of pig RBCs was detected by flow cytometry. RESULTS In vitro, binding of immunoglobulin (Ig) M from naïve human or baboon sera was detected to Gal-/- RBCs but was significantly less than to Gal+/+ RBCs; IgG binding to Gal-/- RBCs was absent or minimal. Sera had minimal cytotoxicity to Gal-/- RBCs compared to Gal+/+ RBCs. Sensitized baboon sera demonstrated much higher IgG binding to Gal-/- RBCs and increased cytotoxicity, but again these were less than to Gal+/+ RBCs. In vivo, the transfusion of relatively small volumes of Gal-/- RBCs was followed by detection of the cells in the baboon's blood for only 5 minutes. CONCLUSION Pig RBCs are rapidly phagocytosed from the primate circulation by a mechanism not involving anti-Gal.
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Affiliation(s)
- Foad J Rouhani
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, USA
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Eckermann JM, Buhler LH, Zhu A, Dor FJMF, Awwad M, Cooper DKC. Initial investigation of the potential of modified porcine erythrocytes for transfusion in primates. Xenotransplantation 2004; 11:18-26. [PMID: 14962289 DOI: 10.1111/j.1399-3089.2004.00087.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
There is a shortage of human blood for transfusion. The possibility of using alpha-galactosidase-treated pig red blood cells (pRBCs) for transfusion into humans has been investigated. pRBCs were treated in vitro with alpha-galactosidase. In vitro binding of antibodies (Abs) in baboon or human sera to untreated/treated pRBCs was assessed by flow cytometry and serum cytotoxicity. In vivo clearance rates of (1) autologous baboon red blood cells (RBCs), (2) unmodified pRBCs, and (3) alpha-galactosidase-treated pRBCs were measured after transfusion into baboons receiving either no treatment or depletion of complement +/- depletion of anti-Gal alpha 1-3Gal (Gal) Ab or of macrophage phagocytes. In vitro binding of baboon or human Abs to treated pRBCs was absent or minimal compared with untreated pRBCs, and serum cytotoxicity was completely inhibited. In vivo autologous baboon RBCs survived for >16 days and unmodified pRBCs for <15 min in an untreated baboon. Treated pRBCs survived for 2 h in an untreated baboon, for 24 h in a complement-depleted baboon, and for 72 h when the baboon was depleted of both complement and anti-Gal Ab, or of complement and macrophage phagocytes. All baboons, however, became sensitized to Gal antigens. Failure to prolong the in vivo survival of treated pRBCs could be due to inadequate removal of Gal epitopes because sensitization to Gal developed, or could imply other, as yet unidentified, causes for RBC destruction. To fully assess the potential of pRBC transfusion in humans, more complete alpha-galactosidase treatment of pRBCs will be required.
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Affiliation(s)
- Jan M Eckermann
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA, USA
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Zhan Y, Brady JL, Irawaty W, Thomas HE, Kay TW, Lew AM. Activated macrophages require T cells for xenograft rejection under the kidney capsule. Immunol Cell Biol 2003. [DOI: 10.1046/j.1440-1711.2003.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Yifan Zhan
- Walter and Eliza Hall Institute of Medical Research Parkville Victoria Australia
| | - Jamie L Brady
- Walter and Eliza Hall Institute of Medical Research Parkville Victoria Australia
| | - Windy Irawaty
- St. Vincent's Institute of Medical Research Melbourne Victoria Australia
| | - Helen E Thomas
- St. Vincent's Institute of Medical Research Melbourne Victoria Australia
| | - Thomas W Kay
- St. Vincent's Institute of Medical Research Melbourne Victoria Australia
| | - Andrew M Lew
- Walter and Eliza Hall Institute of Medical Research Parkville Victoria Australia
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Zhan Y, Brady JL, Irawaty W, Thomas HE, Kay TW, Lew AM. Activated macrophages require T cells for xenograft rejection under the kidney capsule. Immunol Cell Biol 2003; 81:451-8. [PMID: 14636242 DOI: 10.1046/j.1440-1711.2003..x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Transplantation of tissues from other species has been advocated as a way to overcome the extreme shortage of human donors. Rejection, however, remains a major hurdle for clinical xenotransplantation. Although activation of macrophages by T cells is critical for the cellular rejection of xenografts, what other important interactions between these two types of cells remain less defined. When we activated macrophages of immuno-deficient mice (SCID or Rag-/-) using interferon-gamma and lipopolysacharide, xenogeneic cells were rejected by activated macrophages in the peritoneal cavity (which has an abundance of resident macrophages), but were not rejected under the kidney capsule (which requires the recruitment of effectors). This difference between the two sites implies that activated macrophages are inefficient for self-recruitment to peripheral graft sites and that T cells may still be required for the process. To test this hypothesis further, immunodeficient mice that had received xenogeneic cells were infused with peritoneal exudate cells (containing activated macrophages and activated T cells) from preimmunized immunocompetent mice. Xenogeneic cells at both the kidney capsule and peritoneal sites were rejected soon after cell transfer. However, when the exudate cells were transferred into SCID recipients that first had been injected with T cell depleting antibodies, xenograft rejection was only prominent at the peritoneal site but not kidney capsule site. These results argue that activated macrophages (as the result of T cell activation) still require T cells for xenograft rejection at peripheral sites.
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Affiliation(s)
- Yifan Zhan
- Walter and Eliza Hall Institute of Medical Research and St. Vincent's Institute of Medical Research, Melbourne, Victoria, Australia
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Affiliation(s)
- Fabien Sebille
- Department of Immunology, Faculty of Medicine, Imperial College of Science, Technology and Medicine, London, UK
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Cheng J, Glaser RM, Kruger-Grey H, White-Scharf ME, Cooper DKC, Thall AD. Promotion of xenogeneic hematopoietic chimerism in rodents by mononuclear phagocyte depletion. Xenotransplantation 2002; 9:402-9. [PMID: 12371936 DOI: 10.1034/j.1399-3089.2002.01112.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The successful establishment of tolerance toward pig tissues in primates through hematopoietic progenitor cell engraftment is restricted by the rapid disappearance of these cells in the recipient following infusion. We developed and tested the hypothesis that phagocytes of the reticuloendothelial system are responsible for the rapid clearance of infused pig hematopoietic cells using a mouse model. Mice received non-myeloablative conditioning and, on various days, were injected with medronate-encapsulated liposomes (M-L) or control blank liposomes, followed by the intravenous infusion of miniature swine hematopoietic cells. M-L were well-tolerated in mice (n=100) at levels that deplete mononuclear phagocytes. Depletion of mononuclear phagocytes in normal Balb/c mice as well as in severe combined immune deficient mice increased the accumulation of pig hematopoietic cells in the bone marrow (BM) by 10-fold when measured 24 h after the infusion of the cells. Colony-forming unit analysis showed an increased accumulation of pig hematopoietic progenitors in the BM of mice that were infused with medronate-liposomes. We conclude that depletion of mononuclear phagocytes by M-L has the potential to lower the barrier to the establishment of mixed chimerism and tolerance induction in xenotransplantation.
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Affiliation(s)
- J Cheng
- BioTransplant Inc., Charlestown, Massachusetts General Hospital, Boston, MA 02129, USA
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McMorrow IM, Buhler L, Treter S, Neethling FA, Alwayn IPJ, Comrack CA, Kitamura H, Awwad M, DerSimonian H, Cooper DKC, Sachs DH, LeGuern C. Modulation of the in vivo primate anti-Gal response through administration of anti-idiotypic antibodies. Xenotransplantation 2002; 9:106-14. [PMID: 11897003 DOI: 10.1034/j.1399-3089.2002.1o028.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Polyclonal anti-idiotypic antibodies (AIA) were generated against human Gal alpha 1,3Gal antibodies (anti-Gal) isolated from a single donor. Specificity of the AIA was demonstrated by selective binding to anti-Gal antibodies (Ab) and absence of reactivity to non-Gal Ab. The idiotopes identified by AIA were present on anti-Gal Ab from all of the human samples evaluated (n=59) as well as on pooled samples, demonstrating that a restricted number of dominant idiotopes characterized the human anti-Gal Ab response. Furthermore, the AIA had cross-species reactivity with baboon serum samples (n=19), suggesting that the overall shape of the anti-Gal Ab combining site is conserved throughout the Old World primates and providing additional evidence of the limited heterogeneity of the anti-Gal Ab repertoire. In order to evaluate the potential effect of AIA in the modulation of the anti-Gal response in vivo, a baboon was injected with repeated doses of the purified AIA. Following AIA treatment, new Ab were generated that reduced Ab-mediated cytotoxicity to porcine cells. Furthermore, administration of the AIA to a baboon prolonged the survival of intravenously infused pig hematopoietic cells when compared with their survival in a control baboon that did not receive prior AIA treatment but underwent a similar conditioning regimen.
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Affiliation(s)
- Isabel M McMorrow
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston 02129, USA.
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