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Clough DW, King JL, Li F, Shea LD. Integration of Islet/Beta-Cell Transplants with Host Tissue Using Biomaterial Platforms. Endocrinology 2020; 161:5902435. [PMID: 32894299 PMCID: PMC8253249 DOI: 10.1210/endocr/bqaa156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 08/27/2020] [Indexed: 12/30/2022]
Abstract
Cell-based therapies are emerging for type I diabetes mellitus (T1D), an autoimmune disease characterized by the destruction of insulin-producing pancreatic β-cells, as a means to provide long-term restoration of glycemic control. Biomaterial scaffolds provide an opportunity to enhance the manufacturing and transplantation of islets or stem cell-derived β-cells. In contrast to encapsulation strategies that prevent host contact with the graft, recent approaches aim to integrate the transplant with the host to facilitate glucose sensing and insulin distribution, while also needing to modulate the immune response. Scaffolds can provide a supportive niche for cells either during the manufacturing process or following transplantation at extrahepatic sites. Scaffolds are being functionalized to deliver oxygen, angiogenic, anti-inflammatory, or trophic factors, and may facilitate cotransplantation of cells that can enhance engraftment or modulate immune responses. This local engineering of the transplant environment can complement systemic approaches for maximizing β-cell function or modulating immune responses leading to rejection. This review discusses the various scaffold platforms and design parameters that have been identified for the manufacture of human pluripotent stem cell-derived β-cells, and the transplantation of islets/β-cells to maintain normal blood glucose levels.
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Affiliation(s)
- Daniel W Clough
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
| | - Jessica L King
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
| | - Feiran Li
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
| | - Lonnie D Shea
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
- Correspondence: Lonnie D. Shea, Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA. E-mail:
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2
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Abstract
PURPOSE OF REVIEW Pancreatic islet cell transplantation is currently the only curative cell therapy for type 1 diabetes mellitus. However, its potential to treat many more patients is limited by several challenges. The emergence of 3D bioprinting technology from recent advances in 3D printing, biomaterials, and cell biology has provided the means to overcome these challenges. RECENT FINDINGS 3D bioprinting allows for the precise fabrication of complex 3D architectures containing spatially distributed cells, biomaterials (bioink), and bioactive factors. Different strategies to capitalize on this ability have been investigated for the 3D bioprinting of pancreatic islets. In particular, with co-axial bioprinting technology, the co-printability of islets with supporting cells such as endothelial progenitor cells and regulatory T cells, which have been shown to accelerate revascularization of islets and improve the outcome of various transplantations, respectively, has been achieved. 3D bioprinting of islets for generation of an artificial pancreas is a newly emerging field of study with a vast potential to improve islet transplantation.
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Affiliation(s)
- Juewan Kim
- Department of Molecular & Cellular Biology, School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Kyungwon Kang
- Discipline of Medicine, School of Medicine, The University of Adelaide, Adelaide, South Australia, 5000, Australia
| | - Christopher J Drogemuller
- Discipline of Medicine, School of Medicine, The University of Adelaide, Adelaide, South Australia, 5000, Australia
- Central Northern Adelaide Renal and Transplantation Service (CNARTS), The Royal Adelaide Hospital, Adelaide, South Australia, 5000, Australia
| | - Gordon G Wallace
- Intelligent Polymer Research Institute, ARC Centre of Excellence for Electromaterial Science, University of Wollongong, Wollongong, New South Wales, 2522, Australia
| | - P Toby Coates
- Discipline of Medicine, School of Medicine, The University of Adelaide, Adelaide, South Australia, 5000, Australia.
- Central Northern Adelaide Renal and Transplantation Service (CNARTS), The Royal Adelaide Hospital, Adelaide, South Australia, 5000, Australia.
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Ernst AU, Bowers DT, Wang LH, Shariati K, Plesser MD, Brown NK, Mehrabyan T, Ma M. Nanotechnology in cell replacement therapies for type 1 diabetes. Adv Drug Deliv Rev 2019; 139:116-138. [PMID: 30716349 PMCID: PMC6677642 DOI: 10.1016/j.addr.2019.01.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Revised: 01/17/2019] [Accepted: 01/28/2019] [Indexed: 12/12/2022]
Abstract
Islet transplantation is a promising long-term, compliance-free, complication-preventing treatment for type 1 diabetes. However, islet transplantation is currently limited to a narrow set of patients due to the shortage of donor islets and side effects from immunosuppression. Encapsulating cells in an immunoisolating membrane can allow for their transplantation without the need for immunosuppression. Alternatively, "open" systems may improve islet health and function by allowing vascular ingrowth at clinically attractive sites. Many processes that enable graft success in both approaches occur at the nanoscale level-in this review we thus consider nanotechnology in cell replacement therapies for type 1 diabetes. A variety of biomaterial-based strategies at the nanometer range have emerged to promote immune-isolation or modulation, proangiogenic, or insulinotropic effects. Additionally, coating islets with nano-thin polymer films has burgeoned as an islet protection modality. Materials approaches that utilize nanoscale features manipulate biology at the molecular scale, offering unique solutions to the enduring challenges of islet transplantation.
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Affiliation(s)
- Alexander U Ernst
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Daniel T Bowers
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Long-Hai Wang
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Kaavian Shariati
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Mitchell D Plesser
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Natalie K Brown
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Tigran Mehrabyan
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Minglin Ma
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA.
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Zhu H, Li W, Liu Z, Li W, Chen N, Lu L, Zhang W, Wang Z, Wang B, Pan K, Zhang X, Chen G. Selection of Implantation Sites for Transplantation of Encapsulated Pancreatic Islets. TISSUE ENGINEERING PART B-REVIEWS 2018; 24:191-214. [PMID: 29048258 DOI: 10.1089/ten.teb.2017.0311] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Pancreatic islet transplantation has been validated as a valuable therapy for type 1 diabetes mellitus patients with exhausted insulin treatment. However, this therapy remains limited by the shortage of donor and the requirement of lifelong immunosuppression. Islet encapsulation, as an available bioartificial pancreas (BAP), represents a promising approach to enable protecting islet grafts without or with minimal immunosuppression and possibly expanding the donor pool. To develop a clinically implantable BAP, some key aspects need to be taken into account: encapsulation material, capsule design, and implant site. Among them, the implant site exerts an important influence on the engraftment, stability, and biocompatibility of implanted BAP. Currently, an optimal site for encapsulated islet transplantation may include sufficient capacity to host large graft volumes, portal drainage, ease of access using safe and reproducible procedure, adequate blood/oxygen supply, minimal immune/inflammatory reaction, pliable for noninvasive imaging and biopsy, and potential of local microenvironment manipulation or bioengineering. Varying degrees of success have been confirmed with the utilization of liver or extrahepatic sites in an experimental or preclinical setting. However, the ideal implant site remains to be further engineered or selected for the widespread application of encapsulated islet transplantation.
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Affiliation(s)
- Haitao Zhu
- 1 Department of Pediatrics (No. 3 Ward), Northwest Women's and Children's Hospital , Xi'an, China .,2 Department of Hepatobiliary Surgery, the First Affiliated Hospital, Medical School of Xi'an Jiaotong University , Xi'an, China
| | - Wenjing Li
- 1 Department of Pediatrics (No. 3 Ward), Northwest Women's and Children's Hospital , Xi'an, China
| | - Zhongwei Liu
- 3 Department of Cardiology, Shaanxi Provincial People's Hospital , Xi'an, China
| | - Wenliang Li
- 1 Department of Pediatrics (No. 3 Ward), Northwest Women's and Children's Hospital , Xi'an, China
| | - Niuniu Chen
- 1 Department of Pediatrics (No. 3 Ward), Northwest Women's and Children's Hospital , Xi'an, China
| | - Linlin Lu
- 1 Department of Pediatrics (No. 3 Ward), Northwest Women's and Children's Hospital , Xi'an, China
| | - Wei Zhang
- 1 Department of Pediatrics (No. 3 Ward), Northwest Women's and Children's Hospital , Xi'an, China
| | - Zhen Wang
- 1 Department of Pediatrics (No. 3 Ward), Northwest Women's and Children's Hospital , Xi'an, China
| | - Bo Wang
- 2 Department of Hepatobiliary Surgery, the First Affiliated Hospital, Medical School of Xi'an Jiaotong University , Xi'an, China .,4 Institute of Advanced Surgical Technology and Engineering, Xi'an Jiaotong University , Xi'an, China
| | - Kaili Pan
- 5 Department of Pediatrics (No. 2 Ward), Northwest Women's and Children's Hospital , Xi'an, China
| | - Xiaoge Zhang
- 1 Department of Pediatrics (No. 3 Ward), Northwest Women's and Children's Hospital , Xi'an, China
| | - Guoqiang Chen
- 1 Department of Pediatrics (No. 3 Ward), Northwest Women's and Children's Hospital , Xi'an, China
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5
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Abstract
Review of emerging advances and persisting challenges in the engineering and translation of islet encapsulation technologies.
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Affiliation(s)
| | - Long-Hai Wang
- Department of Biological and Environmental Engineering
- Cornell University
- Ithaca
- USA
| | - Minglin Ma
- Department of Biological and Environmental Engineering
- Cornell University
- Ithaca
- USA
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Arifin DR, Valdeig S, Anders RA, Bulte JWM, Weiss CR. Magnetoencapsulated human islets xenotransplanted into swine: a comparison of different transplantation sites. Xenotransplantation 2016; 23:211-21. [PMID: 27225644 DOI: 10.1111/xen.12235] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 03/17/2016] [Indexed: 12/17/2022]
Abstract
BACKGROUND The fate of magnetically labeled, barium-gelled alginate/protamine sulfate/alginate microcapsules (APSA magnetocapsules) following xenotransplantation was assessed by magnetic resonance imaging (MRI) and histopathology. METHODS Magnetocapsules with and without human islets were transplanted into five different clinically accessible sites: portal vein, subcutaneous tissue, skeletal muscle, the liver and the kidney subcapsular space. The surface of APSA magnetocapsules was modified using clinical-grade heparin to mitigate an instant blood-mediated inflammatory reaction. RESULTS The accuracy of site-specific delivery was confirmed using a clinical 1.5T MRI setup, where the magnetocapsules appeared as distinct hypointense entities after transplantation. As proven by the Lee-White blood coagulation test, heparin-treated APSA magnetocapsules did not induce blood clotting for more than 48 h in vitro. Heparinized magnetocapsules induced innate and adaptive immune responses in vivo regardless of the transplantation sites. CONCLUSION We have demonstrated the feasibility of using a clinical 1.5T MRI to non-invasively detect the accuracy of APSA magnetocapsule injection into various clinically accessible transplantation sites. Among the investigated transplantation sites, the liver and kidney subcapsular space were found to be the least immuno-responsive toward xenografted magneto-encapsulated human islets.
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Affiliation(s)
- Dian R Arifin
- Division of MR Research, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.,Institute for Cell Engineering, Cellular Imaging Section and Vascular Biology Program, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Steffi Valdeig
- Interventional Radiology Center, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Robert A Anders
- Gastrointestinal Liver Pathology, Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Jeff W M Bulte
- Division of MR Research, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.,Institute for Cell Engineering, Cellular Imaging Section and Vascular Biology Program, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Chemical & Biomolecular Engineering, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.,Department of Biomedical Engineering, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.,Department of Oncology, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Clifford R Weiss
- Interventional Radiology Center, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
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Staels W, De Groef S, Heremans Y, Coppens V, Van Gassen N, Leuckx G, Van de Casteele M, Van Riet I, Luttun A, Heimberg H, De Leu N. Accessory cells for β-cell transplantation. Diabetes Obes Metab 2016; 18:115-24. [PMID: 26289770 DOI: 10.1111/dom.12556] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 07/22/2015] [Accepted: 08/13/2015] [Indexed: 12/16/2022]
Abstract
Despite recent advances, insulin therapy remains a treatment, not a cure, for diabetes mellitus with persistent risk of glycaemic alterations and life-threatening complications. Restoration of the endogenous β-cell mass through regeneration or transplantation offers an attractive alternative. Unfortunately, signals that drive β-cell regeneration remain enigmatic and β-cell replacement therapy still faces major hurdles that prevent its widespread application. Co-transplantation of accessory non-islet cells with islet cells has been shown to improve the outcome of experimental islet transplantation. This review will highlight current travails in β-cell therapy and focuses on the potential benefits of accessory cells for islet transplantation in diabetes.
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MESH Headings
- Animals
- Cell Proliferation
- Cell Separation/trends
- Cells, Cultured
- Diabetes Mellitus, Type 1/immunology
- Diabetes Mellitus, Type 1/metabolism
- Diabetes Mellitus, Type 1/pathology
- Diabetes Mellitus, Type 1/surgery
- Diabetes Mellitus, Type 2/immunology
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/pathology
- Diabetes Mellitus, Type 2/surgery
- Endothelial Progenitor Cells/cytology
- Endothelial Progenitor Cells/immunology
- Endothelial Progenitor Cells/pathology
- Endothelial Progenitor Cells/transplantation
- Graft Rejection/immunology
- Graft Rejection/metabolism
- Graft Rejection/prevention & control
- Graft Survival
- Humans
- Immune Tolerance
- Insulin-Secreting Cells/cytology
- Insulin-Secreting Cells/immunology
- Insulin-Secreting Cells/metabolism
- Insulin-Secreting Cells/transplantation
- Islets of Langerhans Transplantation/adverse effects
- Islets of Langerhans Transplantation/immunology
- Mesenchymal Stem Cell Transplantation/adverse effects
- Mesenchymal Stem Cell Transplantation/trends
- Neural Crest/cytology
- Neural Crest/immunology
- Neural Crest/pathology
- Neural Crest/transplantation
- Stem Cell Transplantation/adverse effects
- Stem Cell Transplantation/trends
- T-Lymphocytes, Regulatory/cytology
- T-Lymphocytes, Regulatory/immunology
- T-Lymphocytes, Regulatory/pathology
- T-Lymphocytes, Regulatory/transplantation
- Transplantation, Autologous/adverse effects
- Transplantation, Autologous/trends
- Transplantation, Heterotopic/adverse effects
- Transplantation, Heterotopic/trends
- Transplantation, Homologous/adverse effects
- Transplantation, Homologous/trends
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Affiliation(s)
- W Staels
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
- Division of Pediatric Endocrinology, Department of Pediatrics, Ghent University Hospital, Ghent, Belgium
- Department of Pediatrics and Genetics, Ghent University, Ghent, Belgium
| | - S De Groef
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
| | - Y Heremans
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
| | - V Coppens
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
| | - N Van Gassen
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
| | - G Leuckx
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
| | - M Van de Casteele
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
| | - I Van Riet
- Department Hematology Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - A Luttun
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, KU Leuven, Leuven, Belgium
| | - H Heimberg
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
| | - N De Leu
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
- Department of Endocrinology, UZ Brussel, Brussels, Belgium
- Department of Endocrinology, ASZ Aalst, Aalst, Belgium
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Abstract
The liver is the current site of choice for pancreatic islet transplantation, even though it is far from being an ideal site because of immunologic, anatomic, and physiologic factors leading to a significant early graft loss. A huge amount of alternative sites have been used for islet transplantation in experimental animal models to provide improved engraftment and long-term survival minimizing surgical complications. The pancreas, gastric submucosa, genitourinary tract, muscle, omentum, bone marrow, kidney capsule, peritoneum, anterior eye chamber, testis, and thymus have been explored. Site-specific differences exist in term of islet engraftment, but few alternative sites have potential clinical translation and generally the evidence of a post-transplant islet function better than that reached after intraportal infusion is still lacking. This review discusses site-specific benefits and drawbacks taking into account immunologic, metabolic, and technical aspects to identify the ideal microenvironment for islet function and survival.
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Affiliation(s)
- Elisa Cantarelli
- San Raffaele Diabetes Research Institute, San Raffaele Scientific Institute, Milan, Italy.
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Jones KS. Assays on the influence of biomaterials on allogeneic rejection in tissue engineering. TISSUE ENGINEERING PART B-REVIEWS 2009; 14:407-17. [PMID: 18826337 DOI: 10.1089/ten.teb.2008.0264] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
In tissue engineering, innate responses to biomaterial scaffolds will affect rejection of allogeneic cells. Biomaterials directly influence innate and adaptive immune cell adhesion, reactive oxygen intermediate production, cytokine secretion, nuclear factor-kappa B nuclear translocation, gene expression, and cell surface markers, all of which are likely to affect allogeneic rejection responses. A major goal in tissue engineering is to induce transplant tolerance, potentially by manipulating the biomaterial component. This review describes methods of measuring responses of macrophages, dendritic cells, and T cells stimulated in vitro and in vivo and addresses key factors in assay development. Such tests include mixed leukocyte reactions, enzyme-linked immunosorbent spot assays, trans-vivo delayed-type hypersensitivity assays, and measurement of dendritic cell subsets and anti-donor antibodies; we propose extending these studies to tissue engineering.
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Affiliation(s)
- Kim S Jones
- Department of Chemical Engineering, McMaster University, Hamilton, Ontario, Canada.
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Merani S, Toso C, Emamaullee J, Shapiro AMJ. Optimal implantation site for pancreatic islet transplantation. Br J Surg 2008; 95:1449-61. [PMID: 18991254 DOI: 10.1002/bjs.6391] [Citation(s) in RCA: 181] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Since the first report of successful pancreatic islet transplantation to reverse hyperglycaemia in diabetic rodents, there has been great interest in determining the optimal site for implantation. Although the portal vein remains the most frequently used site clinically, it is not ideal. About half of the islets introduced into the liver die during or shortly after transplantation. Although many patients achieve insulin independence after portal vein infusion of islets, in the long term most resume insulin injections. METHODS This review considers possible sites and techniques of islet transplantation in small and large animal models, and in humans. Metabolic, immunological and technical aspects are discussed. RESULTS AND CONCLUSION Many groups have sought an alternative site that might offer improved engraftment and long-term survival, together with reduced procedure-related complications. The spleen, pancreas, kidney capsule, peritoneum and omental pouch have been explored. The advantages and disadvantages of various sites are discussed in order to define the most suitable for clinical use and to direct future research.
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Affiliation(s)
- S Merani
- Surgical Medical Research Institute, University of Alberta, Edmonton, Canada
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Yin D, Tao J, Lee DD, Shen J, Hara M, Lopez J, Kuznetsov A, Philipson LH, Chong AS. Recovery of islet beta-cell function in streptozotocin- induced diabetic mice: an indirect role for the spleen. Diabetes 2006; 55:3256-63. [PMID: 17130468 DOI: 10.2337/db05-1275] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Limitations in islet beta-cell transplantation as a therapeutic option for type 1 diabetes have prompted renewed interest in islet regeneration as a source of new islets. In this study we tested whether severely diabetic adult C57BL/6 mice can regenerate beta-cells. Diabetes was induced in C57BL/6 mice with high-dose streptozotocin (160-170 mg/kg). In the absence of islet transplantation, all diabetic mice remained diabetic (blood glucose >400 mg/dl), and no spontaneous reversal of diabetes was observed. When syngeneic islets (200/mouse) were transplanted into these diabetic mice under a single kidney capsule, stable restoration of euglycemia for >/=120 days was achieved. Removal of the kidney bearing the transplanted islets at 120 days posttransplantation revealed significant restoration of endogenous beta-cell function. This restoration of islet function was associated with increased beta-cell mass, as well as beta-cell hypertrophy and proliferation. The restoration of islet cell function was facilitated by the presence of a spleen; however, the facilitation was not due to the direct differentiation of spleen-derived cells into beta-cells. This study supports the possibility of restoring beta-cell function in diabetic individuals and points to a role for the spleen in facilitating this process.
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Affiliation(s)
- Dengping Yin
- Section of Transplantation, Department of Surgery, The University of Chicago, Chicago, IL 60637, USA
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12
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Kimmel SG, Ohbatake M, Kushida M, Merguerian P, Clarke ID, Kim PC. Murine xenogeneic immune responses to the human testis: a presumed immune-privileged tissue. Transplantation 2000; 69:1075-84. [PMID: 10762210 DOI: 10.1097/00007890-200003270-00010] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
INTRODUCTION Immune privilege provides a natural paradigm for potentially down-regulating allogeneic and xenogeneic inflammatory immune responses. Fas ligand has been suggested as a general underlying mechanism of immune privilege; the human Fas ligand has been shown to ligate murine Fas in vitro. METHODS In this study, we examined whether the human testicular xenograft, a presumed immune-privileged tissue would have prolonged survival in mice. In addition, in vitro and in vivo murine xenogeneic immune responses to the human testicular xenografts were characterized using MHC class I, MHC class II, CD4, CD8, CD4/8 knockout mice. RESULTS Unlike in rodent testis, Fas ligand mRNA is not expressed and Fas is highly expressed in human testis. Human testicular xenografts are immunogenic, and do not induce any preferential pattern of recipient systemic Th1 or Th2 cytokine bias. Interestingly, an indefinite survival of the human testicular xenografts is observed in murine MHC class II knockout mice, whereas the human skin xenografts were rejected without a delay. In vivo murine immune responses to human testicular xenografts require a recipient MHC class II-dependent CD4 T cell-mediated process that appears to depend on B7-1/B7-2 costimulatory signals. CONCLUSIONS Our results demonstrate that the concept of immune privilege, as defined by the expression of Fas ligand and prolonged survival after transplantation, cannot be extended to human testis. The stringent restriction of murine xenogeneic immune responses to discordant human testicular xenografts to the indirect MHC class II-dependent CD4 T cell-mediated pathway suggests a potential venue for immune modulation to induce tolerance across a discordant species barrier.
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Affiliation(s)
- S G Kimmel
- Department of Surgery, The Hospital for Sick Children and The University of Toronto, Ontario, Canada
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13
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Immunoprivileged Sites for Allo-and Xenotransplantation. Xenotransplantation 1997. [DOI: 10.1007/978-3-642-60572-7_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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