1
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Nashimoto Y, Konno A, Imaizumi T, Nishikawa K, Ino K, Hori T, Kaji H, Shintaku H, Goto M, Shiku H. Microfluidic vascular formation model for assessing angiogenic capacities of single islets. Biotechnol Bioeng 2024; 121:1050-1059. [PMID: 38131167 DOI: 10.1002/bit.28631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 09/12/2023] [Accepted: 12/07/2023] [Indexed: 12/23/2023]
Abstract
Pancreatic islet transplantation presents a promising therapy for individuals suffering from type 1 diabetes. To maintain the function of transplanted islets in vivo, it is imperative to induce angiogenesis. However, the mechanisms underlying angiogenesis triggered by islets remain unclear. In this study, we introduced a microphysiological system to study the angiogenic capacity and dynamics of individual islets. The system, which features an open-top structure, uniquely facilitates the inoculation of islets and the longitudinal observation of vascular formation in in vivo like microenvironment with islet-endothelial cell communication. By leveraging our system, we discovered notable islet-islet heterogeneity in the angiogenic capacity. Transcriptomic analysis of the vascularized islets revealed that islets with high angiogenic capacity exhibited upregulation of genes related to insulin secretion and downregulation of genes related to angiogenesis and fibroblasts. In conclusion, our microfluidic approach is effective in characterizing the vascular formation of individual islets and holds great promise for elucidating the angiogenic mechanisms that enhance islet transplantation therapy.
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Affiliation(s)
- Yuji Nashimoto
- Institute of Biomaterials and Bioengineering (IBB), Tokyo Medical and Dental University (TMDU), Tokyo, Japan
- Frontier Research Institute for Interdisciplinary Sciences (FRIS), Tohoku University, Miyagi, Japan
- Graduate School of Engineering, Tohoku University, Miyagi, Japan
- Graduate School of Environmental Studies, Tohoku University, Miyagi, Japan
- Cluster for Pioneering Research, RIKEN, Saitama, Japan
| | - An Konno
- Graduate School of Environmental Studies, Tohoku University, Miyagi, Japan
| | - Takuto Imaizumi
- Graduate School of Environmental Studies, Tohoku University, Miyagi, Japan
| | | | - Kosuke Ino
- Graduate School of Engineering, Tohoku University, Miyagi, Japan
| | - Takeshi Hori
- Institute of Biomaterials and Bioengineering (IBB), Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Hirokazu Kaji
- Institute of Biomaterials and Bioengineering (IBB), Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Hirofumi Shintaku
- Cluster for Pioneering Research, RIKEN, Saitama, Japan
- Institute for Life and Medical Sciences, Kyoto University, Kyoto, Japan
| | - Masafumi Goto
- Division of Transplantation and Regenerative Medicine, Graduate School of Medicine, Tohoku University, Miyagi, Japan
| | - Hitoshi Shiku
- Graduate School of Engineering, Tohoku University, Miyagi, Japan
- Graduate School of Environmental Studies, Tohoku University, Miyagi, Japan
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2
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Urbanczyk M, Jeyagaran A, Zbinden A, Lu CE, Marzi J, Kuhlburger L, Nahnsen S, Layland SL, Duffy G, Schenke-Layland K. Decorin improves human pancreatic β-cell function and regulates ECM expression in vitro. Matrix Biol 2023; 115:160-183. [PMID: 36592738 DOI: 10.1016/j.matbio.2022.12.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 12/23/2022] [Accepted: 12/29/2022] [Indexed: 01/01/2023]
Abstract
Transplantation of islets of Langerhans is a promising alternative treatment strategy in severe cases of type 1 diabetes mellitus; however, the success rate is limited by the survival rate of the cells post-transplantation. Restoration of the native pancreatic niche during transplantation potentially can help to improve cell viability and function. Here, we assessed for the first time the regulatory role of the small leucine-rich proteoglycan decorin (DCN) in insulin secretion in human β-cells, and its impact on pancreatic extracellular matrix (ECM) protein expression in vitro. In depth analyses utilizing next-generation sequencing as well as Raman microspectroscopy and Raman imaging identified pathways related to glucose metabolism to be upregulated in DCN-treated cells, including oxidative phosphorylation within the mitochondria as well as proteins and lipids of the endoplasmic reticulum. We further showed the effectiveness of DCN in a transplantation setting by treating collagen type 1-encapsulated β-cell-containing pseudo-islets with DCN. Taken together, in this study, we demonstrate the potential of DCN to improve the function of insulin-secreting β-cells while reducing the expression of ECM proteins affiliated with fibrotic capsule formation, making DCN a highly promising therapeutic agent for islet transplantation.
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Affiliation(s)
- Max Urbanczyk
- Institute of Biomedical Engineering, Department for Medical Technologies and Regenerative Medicine, Eberhard Karls University Tübingen, Silcherstr. 7/1, Tübingen 72076, Germany
| | - Abiramy Jeyagaran
- Institute of Biomedical Engineering, Department for Medical Technologies and Regenerative Medicine, Eberhard Karls University Tübingen, Silcherstr. 7/1, Tübingen 72076, Germany; NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
| | - Aline Zbinden
- Institute of Biomedical Engineering, Department for Medical Technologies and Regenerative Medicine, Eberhard Karls University Tübingen, Silcherstr. 7/1, Tübingen 72076, Germany; Department of Immunology, Leiden University Medical Center Leiden, ZA 2333, the Netherlands
| | - Chuan-En Lu
- Institute of Biomedical Engineering, Department for Medical Technologies and Regenerative Medicine, Eberhard Karls University Tübingen, Silcherstr. 7/1, Tübingen 72076, Germany
| | - Julia Marzi
- Institute of Biomedical Engineering, Department for Medical Technologies and Regenerative Medicine, Eberhard Karls University Tübingen, Silcherstr. 7/1, Tübingen 72076, Germany; NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany; Cluster of Excellence iFIT (EXC 2180) "Image-Guided and Functionally Instructed Tumor Therapies", Eberhard Karls University Tübingen, Tübingen, Germany
| | - Laurence Kuhlburger
- Quantitative Biology Center (QBiC), Eberhard Karls University of Tübingen, Tübingen, Germany; Biomedical Data Science, Department of Computer Science, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Sven Nahnsen
- Quantitative Biology Center (QBiC), Eberhard Karls University of Tübingen, Tübingen, Germany; Biomedical Data Science, Department of Computer Science, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Shannon L Layland
- Institute of Biomedical Engineering, Department for Medical Technologies and Regenerative Medicine, Eberhard Karls University Tübingen, Silcherstr. 7/1, Tübingen 72076, Germany; Department of Women's Health, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Garry Duffy
- Discipline of Anatomy and the Regenerative Medicine Institute, School of Medicine, College of Medicine Nursing and Health Sciences, National University of Ireland Galway, Ireland; Science Foundation Ireland (SFI) Centre for Research in Advanced Materials for Biomedical Engineering (AMBER), Trinity College Dublin & National University of Ireland Galway, Galway, Ireland
| | - Katja Schenke-Layland
- Institute of Biomedical Engineering, Department for Medical Technologies and Regenerative Medicine, Eberhard Karls University Tübingen, Silcherstr. 7/1, Tübingen 72076, Germany; NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany; Cluster of Excellence iFIT (EXC 2180) "Image-Guided and Functionally Instructed Tumor Therapies", Eberhard Karls University Tübingen, Tübingen, Germany.
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3
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Jeyagaran A, Lu CE, Zbinden A, Birkenfeld AL, Brucker SY, Layland SL. Type 1 diabetes and engineering enhanced islet transplantation. Adv Drug Deliv Rev 2022; 189:114481. [PMID: 36002043 PMCID: PMC9531713 DOI: 10.1016/j.addr.2022.114481] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 08/01/2022] [Accepted: 08/02/2022] [Indexed: 01/24/2023]
Abstract
The development of new therapeutic approaches to treat type 1 diabetes mellitus (T1D) relies on the precise understanding and deciphering of insulin-secreting β-cell biology, as well as the mechanisms responsible for their autoimmune destruction. β-cell or islet transplantation is viewed as a potential long-term therapy for the millions of patients with diabetes. To advance the field of insulin-secreting cell transplantation, two main research areas are currently investigated by the scientific community: (1) the identification of the developmental pathways that drive the differentiation of stem cells into insulin-producing cells, providing an inexhaustible source of cells; and (2) transplantation strategies and engineered transplants to provide protection and enhance the functionality of transplanted cells. In this review, we discuss the biology of pancreatic β-cells, pathology of T1D and current state of β-cell differentiation. We give a comprehensive view and discuss the different possibilities to engineer enhanced insulin-secreting cell/islet transplantation from a translational perspective.
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Affiliation(s)
- Abiramy Jeyagaran
- Institute of Biomedical Engineering, Department for Medical Technologies and Regenerative Medicine, Eberhard Karls University Tübingen, 72076 Tübingen, Germany,NMI Natural and Medical Sciences Institute at the University Tübingen, 72770 Reutlingen, Germany
| | - Chuan-en Lu
- Institute of Biomedical Engineering, Department for Medical Technologies and Regenerative Medicine, Eberhard Karls University Tübingen, 72076 Tübingen, Germany
| | - Aline Zbinden
- Department of Immunology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Andreas L. Birkenfeld
- Department of Internal Medicine IV, University Hospital Tübingen, Tübingen, Germany,Institute for Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the University of Tübingen, German Center for Diabetes Research (DZD e.V.), Munich, Germany
| | - Sara Y. Brucker
- Department of Women's Health, Eberhard Karls University, 72076 Tübingen, Germany
| | - Shannon L. Layland
- Institute of Biomedical Engineering, Department for Medical Technologies and Regenerative Medicine, Eberhard Karls University Tübingen, 72076 Tübingen, Germany,Department of Women's Health, Eberhard Karls University, 72076 Tübingen, Germany,Corresponding author at: Institute of Biomedical Engineering, Department for Medical Technologies and Regenerative Medicine, Eberhard Karls University Tübingen, Silcherstrasse 7/1, 72076 Tübingen, Germany.
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4
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The Potential of Cell Sheet Technology for Beta Cell Replacement Therapy. CURRENT TRANSPLANTATION REPORTS 2022. [DOI: 10.1007/s40472-022-00371-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Abstract
Purpose of Review
Here, we review the use of cell sheet technology using different cell types and its potential for restoring the extracellular matrix microenvironment, perfusion, and immunomodulatory action on islets and beta cells.
Recent Findings
Cell sheets can be produced with different fabrication techniques ranging from the widely used temperature responsive system to the magnetic system. A variety of cells have been used to produce cell sheets including skin fibroblasts, smooth muscle cells, human umbilical vein endothelial cells, and mesenchymal stem cells.
Summary
CST would allow to recreate the ECM of islets which would provide cues to support islet survival and improvement of islet function. Depending on the used cell type, different additional supporting properties like immunoprotection or cues for better revascularization could be provided. Furthermore, CST offers the possibility to use other implantation sites than inside the liver. Further research should focus on cell sheet thickness and size to generate a potential translational therapy.
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5
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Graham ML, Ramachandran S, Singh A, Moore MEG, Flanagan EB, Azimzadeh A, Burlak C, Mueller KR, Martins K, Anazawa T, Balamurugan AN, Bansal-Pakala P, Murtaugh MP, O’Brien TD, Papas KK, Spizzo T, Schuurman HJ, Hancock WW, Hering BJ. Clinically available immunosuppression averts rejection but not systemic inflammation after porcine islet xenotransplant in cynomolgus macaques. Am J Transplant 2022; 22:745-760. [PMID: 34704345 PMCID: PMC9832996 DOI: 10.1111/ajt.16876] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 09/30/2021] [Accepted: 10/19/2021] [Indexed: 01/25/2023]
Abstract
A safe, efficacious, and clinically applicable immunosuppressive regimen is necessary for islet xenotransplantation to become a viable treatment option for diabetes. We performed intraportal transplants of wild-type adult porcine islets in 25 streptozotocin-diabetic cynomolgus monkeys. Islet engraftment was good in 21, partial in 3, and poor in 1 recipient. Median xenograft survival was 25 days with rapamycin and CTLA4Ig immunosuppression. Adding basiliximab induction and maintenance tacrolimus to the base regimen significantly extended median graft survival to 147 days (p < .0001), with three animals maintaining insulin-free xenograft survival for 265, 282, and 288 days. We demonstrate that this regimen suppresses non-Gal anti-pig antibody responses, circulating effector memory T cell expansion, effector function, and infiltration of the graft. However, a chronic systemic inflammatory state manifested in the majority of recipients with long-term graft survival indicated by increased neutrophil to lymphocyte ratio, IL-6, MCP-1, CD40, and CRP expression. This suggests that this immunosuppression regimen fails to regulate innate immunity and resulting inflammation is significantly associated with increased incidence and severity of adverse events making this regimen unacceptable for translation. Additional studies are needed to optimize a maintenance regimen for regulating the innate inflammatory response.
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Affiliation(s)
- Melanie L. Graham
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | | | - Amar Singh
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | - Meghan E. G. Moore
- Department of Veterinary Population Medicine, University of Minnesota, St. Paul, MN
| | - E. Brian Flanagan
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | - Agnes Azimzadeh
- Department of Surgery, University of Maryland, Baltimore, MD
| | - Christopher Burlak
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | - Kate R. Mueller
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | - Kyra Martins
- Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, MN
| | - Takayuki Anazawa
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | | | - Pratima Bansal-Pakala
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | - Michael P. Murtaugh
- Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, MN
| | - Timothy D. O’Brien
- Department of Veterinary Population Medicine, University of Minnesota, St. Paul, MN
| | - Klearchos K. Papas
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | | | - Henk-J. Schuurman
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN,Spring Point Project, Minneapolis, MN
| | - Wayne W. Hancock
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA
| | - Bernhard. J. Hering
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
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6
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Xiong Y, Scerbo MJ, Seelig A, Volta F, O'Brien N, Dicker A, Padula D, Lickert H, Gerdes JM, Berggren PO. Islet vascularization is regulated by primary endothelial cilia via VEGF-A-dependent signaling. eLife 2020; 9:56914. [PMID: 33200981 PMCID: PMC7695455 DOI: 10.7554/elife.56914] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 11/16/2020] [Indexed: 12/31/2022] Open
Abstract
Islet vascularization is essential for intact islet function and glucose homeostasis. We have previously shown that primary cilia directly regulate insulin secretion. However, it remains unclear whether they are also implicated in islet vascularization. At eight weeks, murine Bbs4-/-islets show significantly lower intra-islet capillary density with enlarged diameters. Transplanted Bbs4-/- islets exhibit delayed re-vascularization and reduced vascular fenestration after engraftment, partially impairing vascular permeability and glucose delivery to β-cells. We identified primary cilia on endothelial cells as the underlying cause of this regulation, via the vascular endothelial growth factor-A (VEGF-A)/VEGF receptor 2 (VEGFR2) pathway. In vitro silencing of ciliary genes in endothelial cells disrupts VEGF-A/VEGFR2 internalization and downstream signaling. Consequently, key features of angiogenesis including proliferation and migration are attenuated in human BBS4 silenced endothelial cells. We conclude that endothelial cell primary cilia regulate islet vascularization and vascular barrier function via the VEGF-A/VEGFR2 signaling pathway.
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Affiliation(s)
- Yan Xiong
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska University Hospital L1, Stockholm, Sweden
| | - M Julia Scerbo
- Institute for Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany
| | - Anett Seelig
- Institute for Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany
| | - Francesco Volta
- Institute for Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany.,Technical University Munich, Munich, Germany
| | - Nils O'Brien
- Institute for Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany
| | - Andrea Dicker
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska University Hospital L1, Stockholm, Sweden
| | - Daniela Padula
- Institute for Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany
| | - Heiko Lickert
- Institute for Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany.,Technical University Munich, Munich, Germany.,Deutsches Zentrum für Diabetesforschung, DZD, Munich, Germany
| | - Jantje Mareike Gerdes
- Institute for Diabetes and Regeneration Research, Helmholtz Zentrum München, Neuherberg, Germany.,Deutsches Zentrum für Diabetesforschung, DZD, Munich, Germany
| | - Per-Olof Berggren
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska University Hospital L1, Stockholm, Sweden
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7
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Figueiredo H, Figueroa ALC, Garcia A, Fernandez-Ruiz R, Broca C, Wojtusciszyn A, Malpique R, Gasa R, Gomis R. Targeting pancreatic islet PTP1B improves islet graft revascularization and transplant outcomes. Sci Transl Med 2020; 11:11/497/eaar6294. [PMID: 31217339 DOI: 10.1126/scitranslmed.aar6294] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 01/16/2019] [Accepted: 05/23/2019] [Indexed: 12/12/2022]
Abstract
Deficient vascularization is a major driver of early islet graft loss and one of the primary reasons for the failure of islet transplantation as a viable treatment for type 1 diabetes. This study identifies the protein tyrosine phosphatase 1B (PTP1B) as a potential modulator of islet graft revascularization. We demonstrate that grafts of pancreatic islets lacking PTP1B exhibit increased revascularization, which is accompanied by improved graft survival and function, and recovery of normoglycemia and glucose tolerance in diabetic mice transplanted with PTP1B-deficient islets. Mechanistically, we show that the absence of PTP1B leads to activation of hypoxia-inducible factor 1α-independent peroxisome proliferator-activated receptor γ coactivator 1α/estrogen-related receptor α signaling and enhanced expression and production of vascular endothelial growth factor A (VEGF-A) by β cells. These observations were reproduced in human islets. Together, these findings reveal that PTP1B regulates islet VEGF-A production and suggest that this phosphatase could be targeted to improve islet transplantation outcomes.
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Affiliation(s)
- Hugo Figueiredo
- Diabetes and Obesity Research Laboratory, August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain.,University of Barcelona, 08036 Barcelona, Spain.,Escuela de Medicina y Ciencias de la Salud, Dept. Medicina Cardiovascular y Metabolómica, Tecnológico de Monterrey, 66278 San Pedro Garza García, Nuevo León, Mexico
| | - Ana Lucia C Figueroa
- Diabetes and Obesity Research Laboratory, August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain.,University of Barcelona, 08036 Barcelona, Spain
| | - Ainhoa Garcia
- Diabetes and Obesity Research Laboratory, August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain.,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain
| | - Rebeca Fernandez-Ruiz
- Diabetes and Obesity Research Laboratory, August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain.,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain
| | - Christophe Broca
- CHU Montpellier, Laboratory of Cell Therapy for Diabetes (LTCD), Hospital St-Eloi, 34295 Montpellier, France
| | - Anne Wojtusciszyn
- CHU Montpellier, Laboratory of Cell Therapy for Diabetes (LTCD), Hospital St-Eloi, 34295 Montpellier, France.,Department of Endocrinology, Diabetes and Nutrition, University Hospital of Montpellier, Lapeyronie Hospital, 34295 Montpellier, France.,Service of Endocrinology, Diabetes and Metabolism, Lausanne University Hospital, 1011 Lausanne, Switzerland
| | - Rita Malpique
- Diabetes and Obesity Research Laboratory, August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain
| | - Rosa Gasa
- Diabetes and Obesity Research Laboratory, August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain. .,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain
| | - Ramon Gomis
- Diabetes and Obesity Research Laboratory, August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain. .,University of Barcelona, 08036 Barcelona, Spain.,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain.,Universitat Oberta de Catalunya (UOC), 08018 Barcelona, Spain.,Department of Endocrinology and Nutrition, Hospital Clinic of Barcelona, 08036 Barcelona, Spain
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8
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Bowers DT, Song W, Wang LH, Ma M. Engineering the vasculature for islet transplantation. Acta Biomater 2019; 95:131-151. [PMID: 31128322 PMCID: PMC6824722 DOI: 10.1016/j.actbio.2019.05.051] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 04/13/2019] [Accepted: 05/20/2019] [Indexed: 12/17/2022]
Abstract
The microvasculature in the pancreatic islet is highly specialized for glucose sensing and insulin secretion. Although pancreatic islet transplantation is a potentially life-changing treatment for patients with insulin-dependent diabetes, a lack of blood perfusion reduces viability and function of newly transplanted tissues. Functional vasculature around an implant is not only necessary for the supply of oxygen and nutrients but also required for rapid insulin release kinetics and removal of metabolic waste. Inadequate vascularization is particularly a challenge in islet encapsulation. Selectively permeable membranes increase the barrier to diffusion and often elicit a foreign body reaction including a fibrotic capsule that is not well vascularized. Therefore, approaches that aid in the rapid formation of a mature and robust vasculature in close proximity to the transplanted cells are crucial for successful islet transplantation or other cellular therapies. In this paper, we review various strategies to engineer vasculature for islet transplantation. We consider properties of materials (both synthetic and naturally derived), prevascularization, local release of proangiogenic factors, and co-transplantation of vascular cells that have all been harnessed to increase vasculature. We then discuss the various other challenges in engineering mature, long-term functional and clinically viable vasculature as well as some emerging technologies developed to address them. The benefits of physiological glucose control for patients and the healthcare system demand vigorous pursuit of solutions to cell transplant challenges. STATEMENT OF SIGNIFICANCE: Insulin-dependent diabetes affects more than 1.25 million people in the United States alone. Pancreatic islets secrete insulin and other endocrine hormones that control glucose to normal levels. During preparation for transplantation, the specialized islet blood vessel supply is lost. Furthermore, in the case of cell encapsulation, cells are protected within a device, further limiting delivery of nutrients and absorption of hormones. To overcome these issues, this review considers methods to rapidly vascularize sites and implants through material properties, pre-vascularization, delivery of growth factors, or co-transplantation of vessel supporting cells. Other challenges and emerging technologies are also discussed. Proper vascular growth is a significant component of successful islet transplantation, a treatment that can provide life-changing benefits to patients.
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Affiliation(s)
- Daniel T Bowers
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Wei Song
- 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
| | - Minglin Ma
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA.
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9
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Jiang K, Chaimov D, Patel SN, Liang JP, Wiggins SC, Samojlik MM, Rubiano A, Simmons CS, Stabler CL. 3-D physiomimetic extracellular matrix hydrogels provide a supportive microenvironment for rodent and human islet culture. Biomaterials 2019; 198:37-48. [PMID: 30224090 PMCID: PMC6397100 DOI: 10.1016/j.biomaterials.2018.08.057] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 07/31/2018] [Accepted: 08/27/2018] [Indexed: 01/19/2023]
Abstract
Organ-on-a-chip platforms serve as cost-efficient testbeds for screening pharmaceutical agents, mimicking natural physiology, and studying disease. In the field of diabetes, the development of an islet-on-a-chip platform would have broad implications in understanding disease pathology and discovering potential therapies. Islet microphysiological systems are limited, however, by their poor cell survival and function in culture. A key factor that has been implicated in this decline is the disruption of islet-matrix interactions following isolation. Herein, we sought to recapitulate the in vivo peri-islet niche using decellularized extracellular matrix (ECM) hydrogels. Sourcing from porcine bladder, lung, and pancreas tissues, 3-D ECM hydrogels were generated, characterized, and validated using both rodent and human pancreatic islets. Optimized decellularization protocols resulted in hydrogels with distinctive viscoelastic properties that correlated to their matrix composition. The in situ 3-D encapsulation of human or rat islets within ECM hydrogels resulted in improved functional stability over standard culture conditions. Islet composition and morphology were also altered, with enhanced retention of islet-resident endothelial cells and the formation of cord-like structures or sprouts emerging from the islet spheroid. These supportive 3-D physiomimetic ECM hydrogels can be leveraged within microfluidic platforms for the long-term culture of islets.
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Affiliation(s)
- K Jiang
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, United States
| | - D Chaimov
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, United States
| | - S N Patel
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, United States
| | - J-P Liang
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, United States
| | - S C Wiggins
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, United States
| | - M M Samojlik
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, United States
| | - A Rubiano
- Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL, United States
| | - C S Simmons
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, United States; Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL, United States
| | - C L Stabler
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, United States.
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10
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Abstract
PURPOSES OF REVIEW Scattered throughout the pancreas, the endocrine islets rely on neurovascular support for signal relay to regulate hormone secretion and for maintaining tissue homeostasis. The islet accessory cells (or components) of neurovascular tissues include the endothelial cells, pericytes, smooth muscle cells, neurons (nerve fibers), and glia. Research results derived from experimental diabetes and islet transplantation indicate that the accessory cells are reactive in islet injury and can affect islet function and homeostasis in situ or in an ectopic environment. RECENT FINDINGS Recent advances in cell labeling and tissue imaging have enabled investigation of islet accessory cells to gain insights into their network structures, functions, and remodeling in disease. It has become clear that in diabetes, the islet neurovascular tissues are not just bystanders damaged in neuropathy and vascular complications; rather, they participate in islet remodeling in response to changes in the microenvironment. Because of the fundamental differences between humans and animal models in neuroinsular cytoarchitecture and cell proliferation, examination of islet accessory cells in clinical specimens and donor pancreases warrants further attention.
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Affiliation(s)
- Shiue-Cheng Tang
- Department of Medical Science and Institute of Biotechnology, National Tsing Hua University, Hsinchu, 30013, Taiwan.
| | - Claire F Jessup
- College of Medicine and Public Health, Flinders University and Discipline of Medicine, University of Adelaide, Adelaide, SA, 5001, Australia.
| | - Martha Campbell-Thompson
- Department of Pathology, Immunology, and Laboratory Medicine, 1395 Center Drive, College of Medicine, University of Florida, Gainesville, FL, 32610, USA.
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11
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Boyuk G, Arzu Yigit A, Aydogan I. Co-culture of rat luteal cells with islet cells enhances islet viability and revascularization. In Vitro Cell Dev Biol Anim 2018; 54:640-647. [DOI: 10.1007/s11626-018-0286-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Accepted: 07/27/2018] [Indexed: 10/28/2022]
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12
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Gebe JA, Preisinger A, Gooden MD, D'Amico LA, Vernon RB. Local, Controlled Release In Vivo of Vascular Endothelial Growth Factor Within a Subcutaneous Scaffolded Islet Implant Reduces Early Islet Necrosis and Improves Performance of the Graft. Cell Transplant 2018; 27:531-541. [PMID: 29756517 PMCID: PMC6038045 DOI: 10.1177/0963689718754562] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Islet transplantation remains the only alternative to daily insulin therapy for control of type 1 diabetes (T1D) in humans. To avoid the drawbacks of intrahepatic islet transplantation, we are developing a scaffolded islet implant to transplant islets into nonhepatic sites. The implant test bed, sized for mice, consists of a limited (2-mm) thickness, large-pore polymeric sponge scaffold perforated with peripheral cavities that contain islets suspended in a collagen hydrogel. A central cavity in the scaffold holds a 2-mm diameter alginate sphere for controlled release of the angiogenic cytokine vascular endothelial growth factor ( VEGF). Host microvessels readily penetrate the scaffold and collagen gel to vascularize the islets. Here, we evaluate the performance of the implant in a subcutaneous (SC) graft site. Implants incorporating 500 syngeneic islets reversed streptozotocin-induced diabetes in mice approximately 30 d after SC placement. Controlled release of a modest quantity (20 ng) of VEGF within the implant significantly reduced the time to normoglycemia compared to control implants lacking VEGF. Investigation of underlying causes for this effect revealed that inclusion of 20 ng of VEGF in the implants significantly reduced central necrosis of islets 24 h after grafting and increased implant vascularization (measured 12 d after grafting). Collectively, our results demonstrate (1) that the scaffolded islet implant design can reverse diabetes in SC sites in the absence of prevascularization of the graft site and (2) that relatively low quantities of VEGF, delivered by controlled release within the implant, can be a useful approach to limit islet stress after grafting.
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Affiliation(s)
- John A Gebe
- 1 Matrix Biology Program, Benaroya Research Institute at Virginia Mason, Seattle, WA, USA
| | - Anton Preisinger
- 1 Matrix Biology Program, Benaroya Research Institute at Virginia Mason, Seattle, WA, USA
| | - Michel D Gooden
- 1 Matrix Biology Program, Benaroya Research Institute at Virginia Mason, Seattle, WA, USA
| | - Leonard A D'Amico
- 1 Matrix Biology Program, Benaroya Research Institute at Virginia Mason, Seattle, WA, USA.,2 Cancer Immunotherapy Trials, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Robert B Vernon
- 1 Matrix Biology Program, Benaroya Research Institute at Virginia Mason, Seattle, WA, USA
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13
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Chen CC, Pouliquen E, Broisat A, Andreata F, Racapé M, Bruneval P, Kessler L, Ahmadi M, Bacot S, Saison-Delaplace C, Marcaud M, Van Huyen JPD, Loupy A, Villard J, Demuylder-Mischler S, Berney T, Morelon E, Tsai MK, Kolopp-Sarda MN, Koenig A, Mathias V, Ducreux S, Ghezzi C, Dubois V, Nicoletti A, Defrance T, Thaunat O. Endothelial chimerism and vascular sequestration protect pancreatic islet grafts from antibody-mediated rejection. J Clin Invest 2017; 128:219-232. [PMID: 29202467 DOI: 10.1172/jci93542] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 10/12/2017] [Indexed: 12/31/2022] Open
Abstract
Humoral rejection is the most common cause of solid organ transplant failure. Here, we evaluated a cohort of 49 patients who were successfully grafted with allogenic islets and determined that the appearance of donor-specific anti-HLA antibodies (DSAs) did not accelerate the rate of islet graft attrition, suggesting resistance to humoral rejection. Murine DSAs bound to allogeneic targets expressed by islet cells and induced their destruction in vitro; however, passive transfer of the same DSAs did not affect islet graft survival in murine models. Live imaging revealed that DSAs were sequestrated in the circulation of the recipients and failed to reach the endocrine cells of grafted islets. We used murine heart transplantation models to confirm that endothelial cells were the only accessible targets for DSAs, which induced the development of typical microvascular lesions in allogeneic transplants. In contrast, the vasculature of DSA-exposed allogeneic islet grafts was devoid of lesions because sprouting of recipient capillaries reestablished blood flow in grafted islets. Thus, we conclude that endothelial chimerism combined with vascular sequestration of DSAs protects islet grafts from humoral rejection. The reduced immunoglobulin concentrations in the interstitial tissue, confirmed in patients, may have important implications for biotherapies such as vaccines and monoclonal antibodies.
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Affiliation(s)
- Chien-Chia Chen
- French National Institute of Health and Medical Research (INSERM) Unit 1111, Lyon, France
| | - Eric Pouliquen
- Edouard Herriot University Hospital, Department of Transplantation, Nephrology and Clinical Immunology, Lyon, France
| | - Alexis Broisat
- French National Institute of Health and Medical Research (INSERM) Unit 1039, Grenoble, France; Bioclinical Radiopharmaceutical Laboratory, Joseph Fourier University (Grenoble 1), Grenoble, France
| | - Francesco Andreata
- French National Institute of Health and Medical Research (INSERM) Unit 1148, Laboratory of Vascular Translational Science, F-75018, Paris, France; Paris Diderot University, Paris, France
| | - Maud Racapé
- Paris Translational Research Centre for Organ Transplantation, Paris Descartes University, Paris, France
| | - Patrick Bruneval
- Paris Translational Research Centre for Organ Transplantation, Paris Descartes University, Paris, France
| | - Laurence Kessler
- Department of Diabetology, University Hospital, Strasbourg, France; Federation of Translational Medicine of Strasbourg, University of Strasbourg, Strasbourg, France.,Groupe Rhin-Rhône-Alpes-Genève pour la Greffe d'Ilots de Langerhans (GRAGIL) Consortium
| | - Mitra Ahmadi
- French National Institute of Health and Medical Research (INSERM) Unit 1039, Grenoble, France; Bioclinical Radiopharmaceutical Laboratory, Joseph Fourier University (Grenoble 1), Grenoble, France
| | - Sandrine Bacot
- French National Institute of Health and Medical Research (INSERM) Unit 1039, Grenoble, France; Bioclinical Radiopharmaceutical Laboratory, Joseph Fourier University (Grenoble 1), Grenoble, France
| | - Carole Saison-Delaplace
- French National Institute of Health and Medical Research (INSERM) Unit 1111, Lyon, France.,Edouard Herriot University Hospital, Department of Transplantation, Nephrology and Clinical Immunology, Lyon, France
| | - Marina Marcaud
- Edouard Herriot University Hospital, Department of Transplantation, Nephrology and Clinical Immunology, Lyon, France
| | - Jean-Paul Duong Van Huyen
- Paris Translational Research Centre for Organ Transplantation, Paris Descartes University, Paris, France
| | - Alexandre Loupy
- Paris Translational Research Centre for Organ Transplantation, Paris Descartes University, Paris, France.,Department of Kidney Transplantation, Necker Hospital, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Jean Villard
- Department of Immunology and Allergy and Department of Laboratory Medicine, Geneva University Hospital, Geneva, Switzerland
| | - Sandrine Demuylder-Mischler
- Department of Surgery, Islet Isolation, and Transplantation Center, Geneva University Hospitals, Geneva, Switzerland
| | - Thierry Berney
- Groupe Rhin-Rhône-Alpes-Genève pour la Greffe d'Ilots de Langerhans (GRAGIL) Consortium.,Department of Surgery, Islet Isolation, and Transplantation Center, Geneva University Hospitals, Geneva, Switzerland
| | - Emmanuel Morelon
- French National Institute of Health and Medical Research (INSERM) Unit 1111, Lyon, France.,Edouard Herriot University Hospital, Department of Transplantation, Nephrology and Clinical Immunology, Lyon, France.,Groupe Rhin-Rhône-Alpes-Genève pour la Greffe d'Ilots de Langerhans (GRAGIL) Consortium.,Lyon-Est Medical Faculty, Claude Bernard University (Lyon 1), Lyon, France
| | - Meng-Kun Tsai
- Department of Surgery, National Taiwan University Hospital and National Taiwan University, College of Medicine, Taipei, Taiwan
| | | | - Alice Koenig
- French National Institute of Health and Medical Research (INSERM) Unit 1111, Lyon, France
| | - Virginie Mathias
- French National Blood Service (EFS), HLA Laboratory, Lyon, France
| | | | - Catherine Ghezzi
- French National Institute of Health and Medical Research (INSERM) Unit 1039, Grenoble, France; Bioclinical Radiopharmaceutical Laboratory, Joseph Fourier University (Grenoble 1), Grenoble, France
| | - Valerie Dubois
- French National Blood Service (EFS), HLA Laboratory, Lyon, France
| | - Antonino Nicoletti
- French National Institute of Health and Medical Research (INSERM) Unit 1148, Laboratory of Vascular Translational Science, F-75018, Paris, France; Paris Diderot University, Paris, France
| | - Thierry Defrance
- French National Institute of Health and Medical Research (INSERM) Unit 1111, Lyon, France
| | - Olivier Thaunat
- French National Institute of Health and Medical Research (INSERM) Unit 1111, Lyon, France.,Edouard Herriot University Hospital, Department of Transplantation, Nephrology and Clinical Immunology, Lyon, France.,Groupe Rhin-Rhône-Alpes-Genève pour la Greffe d'Ilots de Langerhans (GRAGIL) Consortium.,Lyon-Est Medical Faculty, Claude Bernard University (Lyon 1), Lyon, France
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Rivas-Carrillo JD, Navarro-Alvarez N, Soto-Gutierrez A, Okitsu T, Chen Y, Tabata Y, Misawa H, Noguchi H, Matsumoto S, Tanaka N, Kobayashi N. Amelioration of Diabetes in Mice after Single-Donor Islet Transplantation Using the Controlled Release of Gelatinized FGF-2. Cell Transplant 2017; 15:939-44. [PMID: 17299999 DOI: 10.3727/000000006783981323] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Fibroblast growth factor (FGF)-2 has been recognized to be a key element involved in angiogenesis and a putative factor involved in stem cell-mediated islet regeneration. However, the usefulness of FGF-2 in an islet transplantation setting has not yet been explored. We therefore evaluated the effect of FGF-2 on both islet culture and islet transplantation. Isolated islets were cultured in the presence of 100 ng/ml FGF-2 for a week and then the glucose-responding insulin secretion and insulin contents were measured. Gelatinized FGF-2 (100 ng), which allowed the controlled release of FGF-2, was used for islet transplantation of streptozotocin-induced diabetic mice. Islets (150 IEQ), obtained from a single donor, mixed with gelatinized FGF-2, were transplanted into the subrenal capsule of the mice and the animals were observed for 30 days. Revascularization around the islet grafts was examined. The blood glucose levels were measured and the intraperitoneal glucose tolerance test (IPGTT) was performed. The supplementation of FGF-2 maintained proper insulin secretion and insulin contents in an in vitro culture. The use of gelatinized FGF-2 facilitated revascularization and favorable islet engraftment, thus resulting in an amelioration of the blood glucose levels in diabetic mice. The utilization of FGF-2 showed increased contents of insulin in the islet grafts and revealed a similar pattern as that of normal healthy mice in IPGTT. In contrast, the transplantation of islets without FGF-2 supplementation showed poor revascularization and failed to control the blood glucose levels in the diabetic mice.
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Affiliation(s)
- Jorge David Rivas-Carrillo
- Department of Surgery, Okayama University Graduate School of Medicine and Dentistry, Okayama 700-8558, Japan
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15
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Johansson A, Sandvik D, Carlsson PO. Inhibition of p38 MAP Kinase in the Early Posttransplantation Phase Redistributes Blood Vessels from the Surrounding Stroma into the Transplanted Endocrine Tissue. Cell Transplant 2017; 15:483-8. [PMID: 17121159 DOI: 10.3727/000000006783981729] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Transplanted pancreatic islets attain a chronically decreased vascular density following transplantation, despite the increased concentrations of vascular endothelial growth factor (VEGF) secreted from beta-cells in response to hypoxia during culture and in the immediate posttransplantation phase. VEGF, however, exerts dual effects on endothelial cells, and in islet endothelial cells of the adult, the vascular permeability-inducing effects of VEGF seem normally more pronounced than those to induce angiogenesis. p38 MAP kinase activity has recently been shown to serve as a switch to separate these properties of VEGF; inhibition of p38 MAP kinase activity enhances VEGF-induced angiogenesis and, at the same time, abrogates VEGF-induced vascular permeability. We hypothesized that the revascularization of transplanted islets may be hampered by a predisposition of adult islet endothelial cells to react to VEGF by forming fenestrae rather than migrating and proliferating. We therefore administered the p38 MAP kinase inhibitor SB203580 by daily IP injections for the first 14 days following transplantation, and then studied the influence of this treatment on the oxygen tension, blood perfusion, and vascular density of the islet grafts 1 month posttransplantation. SB203580 treatment redistributed islet graft blood vessels from the stroma into the endocrine tissue, and this redistribution of blood vessels into the endocrine tissue was accompanied by an increased oxygenation of the islet cells. However, the total number of blood vessels in the tissue was not affected. The blood perfusion of the islet grafts was also similar in control and SB203580-treated animals. Our results suggest that effects of VEGF to preferentially induce vascular permeability may partially contribute to, but is not the main cause of, low revascularization of transplanted islets.
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Affiliation(s)
- Asa Johansson
- Department of Medical Cell Biology, Uppsala University, SE-751 23 Uppsala, Sweden
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16
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Kidszun A, Schneider D, Erb D, Hertl G, Schmidt V, Eckhard M, Preissner KT, Breier G, Bretzel RG, Linn T. Isolated Pancreatic Islets in Three-Dimensional Matrices are Responsive to Stimulators and Inhibitors of Angiogenesis. Cell Transplant 2017; 15:489-97. [PMID: 17121160 DOI: 10.3727/000000006783981774] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The formation of a new microvasculature is essential for the long-term survival and function of the islet graft. In this study we examined endothelium of isolated pancreatic islets by stimulation with growth factors, different culture conditions, and genetic modification. We also inspected the effect of immunosuppressives used in human transplantation on angiogenesis. Isolated islets were embedded in a three-dimensional fibrin or Matrigel matrix. The effect of hyperglycemia, hypoxia, and the addition of VEGF and bFGF was investigated. We exposed islets from transgenic mice expressing the VEGF gene (RIP1VEGF-A) to high glucose (16.7 mmol/L) medium and tested the immunosuppressive agents rapamycin (100 ng/ml) and FK506 (100 ng/ml). To quantify angiogenesis the percentage of sprouting islets was determined. New endothelial capillary-like structures protruded from isolated pancreatic islets. Addition of VEGF to the islets and transgenic RIP-VEGF islets showed a two- to threefold increase of sprouting islets compared to control. Hypoxic culture conditions stimulated angiogenesis, resulting in a twofold increase of capillary sprouting. Rapamycin and FK506 proved to be potent inhibitors of angiogenesis in this system, because a decrease of sprouting islets of more than 20% by both agents was observed. Isolated pancreatic islets are capable of forming new capillary structures and are susceptible to pro- and antiangiogenic stimuli.
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Affiliation(s)
- André Kidszun
- Medical Clinic and Policlinic 3, Justus Liebig University, Rodthohl 6, 35392 Giessen, Germany
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17
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Sabek OM, Fraga DW, Henry J, Gaber LW, Kotb M, Gaber AO. Expression of Transforming Growth Factor-β by Human Islets: Impact on Islet Viability and Function. Cell Transplant 2017; 16:775-85. [DOI: 10.3727/000000007783465217] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Transforming growth factor-β1 (TGF-β1) is a pleotropic cytokine that promotes angiogenesis and extracellular matrix protein synthesis in addition to its immunosuppressive effects. The purpose of this study is to identify optimal conditions for in vivo expression of TGF-β1 by human islets to exploit the possible beneficial effects and minimize undesirable side effects. We transduced human islets with adenoviral vectors encoding the active form of Ad-TGF-β1 or Ad-LacZ to test the effects of TGF-β1 gene expression on islet in vivo function following their transplantation into a NOD-SCID mouse model. Islets were transduced with multiplicity of infection (MOI) of 20, 10, 5, and 2.5 per islet cell. At a MOI ranging from 2.5 to 20, expression of TGF-β1 in islet supernatant persisted for 1–2 months and ranged from 153 ± 5 to 2574 ± 1299 pg/ml, respectively. Transduction with the lowest MOI (2.5) did not compromise the in vivo production of human C-peptide. We conclude that TGF-β1 expression in transplanted islets does not compromise viability and that adenoviral transduction with the TGF-β1 gene has a dose-dependent effect, with larger MOIs being deleterious. The data also indicate that in vitro culture system and the in vivo NOD-SCID model could be used successfully to evaluate the nonimmune effects of gene transduction.
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Affiliation(s)
- Omaima M. Sabek
- Department of Surgery, Methodist Hospital/Cornell University, Physicians Organization, Houston, TX, USA
| | - Daniel W. Fraga
- Department of Surgery, Methodist Hospital/Cornell University, Physicians Organization, Houston, TX, USA
| | - James Henry
- Environmental Health and Safety, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Lillian W. Gaber
- Department of Surgery, Methodist Hospital/Cornell University, Physicians Organization, Houston, TX, USA
| | - Malak Kotb
- Department of Surgery, Division of Transplantation, University of Tennessee, Memphis, TN, USA
| | - A. Osama Gaber
- Department of Surgery, Methodist Hospital/Cornell University, Physicians Organization, Houston, TX, USA
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18
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Linn T, Erb D, Schneider D, Kidszun A, Elçin AE, Bretzel RG, Elçin YM. Polymers for Induction of Revascularization in the Rat Fascial Flap: Application of Vascular Endothelial Growth Factor and Pancreatic Islet Cells. Cell Transplant 2017; 12:769-78. [PMID: 14653623 DOI: 10.3727/000000003108747244] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
One of the major obstacles in transplanting avascular tissue or metabolically active cells for ischemic diseases is the loss of transplanted cells due to lack of oxygen and nutrients in the early posttransplantation period. Biodegradable polymeric tissue engineering scaffolds and hydrogels have a potential to incorporate cells or cellular organoids such as islets of Langerhans and growth factors. In this study, we tested the efficiency of two types of polymeric materials to carry recombinant human vascular endothelial growth factor (rhVEGF) or pancreatic tumor cell lines, namely Ins-1 and AR42J, for the induction of new vessels. Chitosan hydrogel fibers with micropores were prepared and molded into a cylinder construct (5 mm φ 8 mm height). Macroporous PLGA scaffolds with a pore size of 250–400 μm were prepared and cut into cylinders (6 mm φ 3 mm height). Both chitosan and PLGA constructs were loaded with rhVEGF (3 μg) or seeded with the cell lines (5 × 105 cells and 3 × 105 cells/construct, respectively, for AR42J and INS-1 cells), and transplanted into the fascial flaps of Wistar rats. At distinct time points up to 4 weeks postimplantation, polymers were explanted, fixed, and vessel density was counted on sections stained with anti-Factor-VIII antibody. Additionally, the kinetics of rhVEGF release from PLGA microspheres (φ of 50–80 μm) was determined using VEGF Elisa. Endogenous VEGF release from pancreatic rat cell lines was also determined. Light microscopy study was performed on H&E-stained paraffin sections of the islet-polymer samples. The vascular density of rhVEGF-loaded chitosan constructs was increased fourfold 2 weeks after subcutaneous transplantation compared with rhVEGF-unloaded controls (465 ± 144 vs. 104 ± 80 vessels per mm2, p < 0.05). Protein leakage occurred, but was not observed after 2 weeks. Higher insulin content was detected in rat islet grafts transplanted following VEGF application. More than 50% of total rhVEGF was released on the first day of in vitro culture of PLGA microspheres. rhVEGF secretion had another, but smaller, peak on the third day followed by a constant release. By comparison, endogeneous VEGF secretion of pancreatic tumor cells was measured within a 3-day culture period. Biodegradable polymer scaffolds and hydrogels may have potential use as solid supports to induce angiogenesis for pancreatic cell transplantation.
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Affiliation(s)
- Thomas Linn
- Justus Liebig University, Medical Clinic and Policlinic 3, 35392 Giessen, Germany.
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19
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Li Y, Fan P, Ding XM, Tian XH, Feng XS, Yan H, Pan XM, Tian PX, Zheng J, Ding CG, Xue WJ. Polyglycolic Acid Fibrous Scaffold Improving Endothelial Cell Coating and Vascularization of Islet. Chin Med J (Engl) 2017; 130:832-839. [PMID: 28345548 PMCID: PMC5381318 DOI: 10.4103/0366-6999.202730] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background: Improving islet graft revascularization has become a crucial task for prolonging islet graft survival. Endothelial cells (ECs) are the basis of new microvessels in an isolated islet, and EC coating has been demonstrated to improve the vascularization and survival of an islet. However, the traditional method of EC coating of islets has low efficiency in vitro. This study was conducted to evaluate the effect of a polyglycolic acid (PGA) scaffold on the efficiency of islet coating by ECs and the angiogenesis in the coated islet graft. Methods: A PGA fibrous scaffold was used for EC coating of islet culture and was evaluated for its efficiency of EC coating on islets and islet graft angiogenesis. Results: In in vitro experiments, we found that apoptosis index of ECs-coating islet in PGA group (27% ± 8%) was significantly lower than that in control group (83% ± 20%, P < 0.05) after 7 days culture. Stimulation index was significantly greater in the PGA group than in the control group at day 7 after ECs-coating (2.07 ± 0.31 vs. 1.80 ± 0.23, P < 0.05). vascular endothelial growth factor (VEGF) level in the PGA group was significantly higher than the coating in the control group after 7 days culture (52.10 ± 13.50 ng/ml vs. 16.30 ± 8.10 ng/ml, P < 0.05). Because of a tight, circumvallated, adhesive and three-dimensional growth microenvironment, islet cultured in a PGA scaffold had higher coating efficiency showing stronger staining intensity of enzyme than those in the control group after 14 days of culture following ECs-coating. For in vivo study, PGA scaffold significantly prolonged the average survival time of EC-coated islet graft after transplantation compared with control group (15.30 ± 5.60 days vs. 8.30 ± 2.45 days, P < 0.05). The angiogenesis and area of survived grafts were more in the PGA group compared with the control group by measuring the mean microvessel density (8.60 ± 1.21/mm2 vs. 5.20 ± 0.87/mm2, P < 0.05). In addition, expression of VEGF and tyrosin-protein kinase receptor (Tie-2) gene increased in PGA scaffold group than that in control group by real-time reverse transcription-polymerase chain reaction analysis. Conclusions: These results demonstrate that the efficiency of EC coating of islets was successfully increased by culturing ECs on a PGA scaffold. This method enhances the function, survival, and vascularization of isolated islets in vitro and in vivo.
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Affiliation(s)
- Yang Li
- Department of Renal Transplantation, Center of Nephrology, The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi 710061, China
| | - Ping Fan
- Department of Rheumatism and Immunology, The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi 710061, China
| | - Xiao-Ming Ding
- Department of Renal Transplantation, Center of Nephrology, The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi 710061, China
| | - Xiao-Hui Tian
- Department of Renal Transplantation, Center of Nephrology, The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi 710061, China
| | - Xin-Shun Feng
- Department of Renal Transplantation, Center of Nephrology, The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi 710061, China
| | - Hang Yan
- Department of Renal Transplantation, Center of Nephrology, The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi 710061, China
| | - Xiao-Ming Pan
- Department of Renal Transplantation, Center of Nephrology, The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi 710061, China
| | - Pu-Xun Tian
- Department of Renal Transplantation, Center of Nephrology, The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi 710061, China
| | - Jin Zheng
- Department of Renal Transplantation, Center of Nephrology, The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi 710061, China
| | - Chen-Guang Ding
- Department of Renal Transplantation, Center of Nephrology, The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi 710061, China
| | - Wu-Jun Xue
- Department of Renal Transplantation, Center of Nephrology, The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi 710061, China
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20
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Narayanan S, Loganathan G, Dhanasekaran M, Tucker W, Patel A, Subhashree V, Mokshagundam S, Hughes MG, Williams SK, Balamurugan AN. Intra-islet endothelial cell and β-cell crosstalk: Implication for islet cell transplantation. World J Transplant 2017; 7:117-128. [PMID: 28507914 PMCID: PMC5409911 DOI: 10.5500/wjt.v7.i2.117] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 02/28/2017] [Accepted: 03/24/2017] [Indexed: 02/05/2023] Open
Abstract
The intra-islet microvasculature is a critical interface between the blood and islet endocrine cells governing a number of cellular and pathophysiological processes associated with the pancreatic tissue. A growing body of evidence indicates a strong functional and physical interdependency of β-cells with endothelial cells (ECs), the building blocks of islet microvasculature. Intra-islet ECs, actively regulate vascular permeability and appear to play a role in fine-tuning blood glucose sensing and regulation. These cells also tend to behave as “guardians”, controlling the expression and movement of a number of important immune mediators, thereby strongly contributing to the physiology of islets. This review will focus on the molecular signalling and crosstalk between the intra-islet ECs and β-cells and how their relationship can be a potential target for intervention strategies in islet pathology and islet transplantation.
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21
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Establishment, characterization and long-term culture of human endocrine pancreas-derived microvascular endothelial cells. Cytotherapy 2017; 19:141-152. [DOI: 10.1016/j.jcyt.2016.10.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 10/07/2016] [Accepted: 10/12/2016] [Indexed: 12/24/2022]
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22
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Silva PN, Atto Z, Regeenes R, Tufa U, Chen YY, Chan WCW, Volchuk A, Kilkenny DM, Rocheleau JV. Highly efficient adenoviral transduction of pancreatic islets using a microfluidic device. LAB ON A CHIP 2016; 16:2921-2934. [PMID: 27378588 DOI: 10.1039/c6lc00345a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Tissues are challenging to genetically manipulate due to limited penetration of viral particles resulting in low transduction efficiency. We are particularly interested in expressing genetically-encoded sensors in ex vivo pancreatic islets to measure glucose-stimulated metabolism, however poor viral penetration biases these measurements to only a subset of cells at the periphery. To increase mass transfer of viral particles, we designed a microfluidic device that holds islets in parallel hydrodynamic traps connected by an expanding by-pass channel. We modeled viral particle flow into the tissue using fluorescently-labelled gold nanoparticles of varying sizes and showed a penetration threshold of only ∼5 nm. To increase this threshold, we used EDTA to transiently reduce cell-cell adhesion and expand intercellular space. Ultimately, a combination of media flow and ETDA treatment significantly increased adenoviral transduction to the core of the islet. As proof-of-principle, we used this protocol to transduce an ER-targeted redox sensitive sensor (eroGFP), and revealed significantly greater ER redox capacity at core islet cells. Overall, these data demonstrate a robust method to enhance transduction efficiency of islets, and potentially other tissues, by using a combination of microfluidic flow and transient tissue expansion.
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Affiliation(s)
- Pamuditha N Silva
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College St., Toronto, Ontario M5S 3G9, Canada.
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23
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Buitinga M, Janeczek Portalska K, Cornelissen DJ, Plass J, Hanegraaf M, Carlotti F, de Koning E, Engelse M, van Blitterswijk C, Karperien M, van Apeldoorn A, de Boer J. Coculturing Human Islets with Proangiogenic Support Cells to Improve Islet Revascularization at the Subcutaneous Transplantation Site. Tissue Eng Part A 2016; 22:375-85. [PMID: 26871862 DOI: 10.1089/ten.tea.2015.0317] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
While subcutaneous tissue has been proposed as a clinically relevant site for pancreatic islet transplantation, a major issue of concern remains, which is its poor vascular state. In an effort to overcome this limitation, we present an efficient and reproducible method to form human composite islets (CIs) with proangiogenic cell types in a controlled manner using nonadherent agarose microwell templates. In this study, we assessed the three-dimensional structure, function, and angiogenic potential of human CIs with human mesenchymal stromal cells (hMSCs), with or without human umbilical vein endothelial cells (HUVECs), and preconditioned hMSCs (PC-hMSCs) in EGM-2 under shear stress. Distinct cellular rearrangements could be observed in CIs, but islet functionality was maintained. In vitro angiogenesis assays found significantly enhanced sprout formation in case of CIs. In particular, the number of sprouts emanating from CIs with PC-hMSCs was significantly increased compared to other conditions. Subsequent in vivo assessment confirmed the proangiogenic potential of CIs. However, in contrast to our in vitro angiogenesis assays, CIs with hMSCs and HUVECs exhibited a higher in vivo angiogenic potential compared to control islets or islets combined with hMSCs or PC-hMSCs. These findings highlight the importance and necessity of verifying in vitro studies with in vivo models to reliably predict, in this case, revascularization outcomes. Regardless, we demonstrate here the therapeutic potential of CIs with proangiogenic support cells to enhance islet revascularization at a clinically relevant, although poorly vascularized, transplantation site.
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Affiliation(s)
- Mijke Buitinga
- 1 Department of Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente , Enschede, The Netherlands
| | - Karolina Janeczek Portalska
- 2 Department of Tissue Regeneration, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente , Enschede, The Netherlands
| | - Dirk-Jan Cornelissen
- 1 Department of Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente , Enschede, The Netherlands
| | - Jacqueline Plass
- 1 Department of Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente , Enschede, The Netherlands
| | - Maaike Hanegraaf
- 3 Department of Nephrology, Leiden University Medical Center , Leiden, The Netherlands
| | - Françoise Carlotti
- 3 Department of Nephrology, Leiden University Medical Center , Leiden, The Netherlands
| | - Eelco de Koning
- 3 Department of Nephrology, Leiden University Medical Center , Leiden, The Netherlands .,4 Department of Endocrinology, Leiden University Medical Center , Leiden, The Netherlands .,5 Hubrecht Institute-Royal Netherlands Academy of Arts and Sciences (KNAW) and University Medical Center Utrecht , Utrecht, The Netherlands
| | - Marten Engelse
- 3 Department of Nephrology, Leiden University Medical Center , Leiden, The Netherlands
| | - Clemens van Blitterswijk
- 6 Department of Complex Tissue Regeneration, Institute for Technology Inspired Regenerative Medicine (MERLN), Maastricht University , Maastricht, The Netherlands
| | - Marcel Karperien
- 1 Department of Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente , Enschede, The Netherlands
| | - Aart van Apeldoorn
- 1 Department of Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente , Enschede, The Netherlands
| | - Jan de Boer
- 7 Laboratory for Cell Biology-Inspired Tissue Engineering, Institute for Technology Inspired Regenerative Medicine (MERLN) , Maastricht, The Netherlands
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24
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Riopel M, Trinder M, Wang R. Fibrin, a scaffold material for islet transplantation and pancreatic endocrine tissue engineering. TISSUE ENGINEERING PART B-REVIEWS 2014; 21:34-44. [PMID: 24947304 DOI: 10.1089/ten.teb.2014.0188] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Fibrin is derived from fibrinogen during injury to produce a blood clot and thus promote wound repair. Composed of different domains, including Arg-Gly-Asp amino acid motifs, fibrin is used extensively as a hydrogel and sealant in the clinic. By binding to cell surface receptors like integrins and acting as a supportive 3D scaffold, fibrin has been useful in promoting cell differentiation, proliferation, function, and survival. In particular, fibrin has been able to maintain islet cell architecture, promote beta cell insulin secretion, and islet angiogenesis, as well as inducing a protective effect against cell death. During islet transplantation, fibrin improved neovascularization and islet function. These improvements resulted in reduced number of transplanted islets necessary to reverse diabetes. Therefore, fibrin, as a biocompatible and biodegradable scaffold, should be considered during subcutaneous islet transplantation and beta cell expansion in vitro to ensure maintenance of islet cell function, proliferation, and survival to develop effective cell-based therapies for the treatment of diabetes.
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Affiliation(s)
- Matthew Riopel
- 1 Children's Health Research Institute, London, Ontario, Canada
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25
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Culturing Free-Floating and Fibrin-Embedded Islets with Endothelial Cells: Effects on Insulin Secretion and Apoptosis. Cell Mol Bioeng 2014. [DOI: 10.1007/s12195-014-0332-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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26
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Clarkin CE, King AJ, Dhadda P, Chagastelles P, Nardi N, Wheeler-Jones CP, Jones PM. Activin receptor-like kinase 5 inhibition reverses impairment of endothelial cell viability by endogenous islet mesenchymal stromal cells. Stem Cells 2014; 31:547-59. [PMID: 23255220 DOI: 10.1002/stem.1305] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 11/06/2012] [Accepted: 11/21/2012] [Indexed: 01/08/2023]
Abstract
Following islet transplantation, islet graft revascularization is compromised due to loss of endothelial cells (ECs) during islet culture. TGF-β signaling pathways are essential for vascular homeostasis but their importance for islet EC function is unclear. We have identified a population of multipotent mesenchymal stromal cells (MSCs) within islets and investigated how modulation of TGF-β signaling by these cells influences islet EC viability. Cultured islets exhibited reduced expression of EC markers (VEGFR2, VE-cadherin and CD31), which was associated with diminished but sustained expression of endoglin a marker of both ECs and MSCs. Double fluorescent labeling of islets in situ with the EC marker CD31 disclosed a population of CD31-negative cells which were positive for endoglin. In vitro coculture of microvascular ECs with endoglin-positive, CD31-negative islet MSCs reduced VEGFR2 protein expression, disrupted EC angiogenic behavior, and increased EC detachment. Medium conditioned by islet MSCs significantly decreased EC viability and increased EC caspase 3/7 activity. EC:MSC cocultures showed enhanced Smad2 phosphorylation consistent with altered ALK5 signaling. Pharmacological inhibition of ALK5 activity with SB431542 (SB) improved EC survival upon contact with MSCs, and SB-treated cultured islets retained EC marker expression and sensitivity to exogenous VEGF164 . Thus, endoglin-expressing islet MSCs influence EC ALK5 signaling in vitro, which decreases EC viability, and changes in ALK5 activity in whole cultured islets contribute to islet EC loss. Modifying TGF-β signaling may enable maintenance of islet ECs during islet isolation and thus improve islet graft revascularization post-transplantation.
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Affiliation(s)
- Claire E Clarkin
- Diabetes Research Group, Division of Diabetes and Nutritional Sciences, School of Medicine, Kings College London, London, UK.
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27
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Samikannu B, Chen C, Lingwal N, Padmasekar M, Engel FB, Linn T. Dipeptidyl peptidase IV inhibition activates CREB and improves islet vascularization through VEGF-A/VEGFR-2 signaling pathway. PLoS One 2013; 8:e82639. [PMID: 24349326 PMCID: PMC3859629 DOI: 10.1371/journal.pone.0082639] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2013] [Accepted: 11/04/2013] [Indexed: 01/09/2023] Open
Abstract
Substitution of pancreatic islets is a potential therapy to treat diabetes and it depends on reconstitution of islet’s capillary network. In this study, we addressed the question whether stabilization of Glucagon-Like-Peptide-1 (GLP-1) by inhibiting Dipeptidyl Peptidase-IV (DPP-IV) increases β-cell mass by modulating vascularization. Mouse or porcine donor islets were implanted under kidney capsule of diabetic mice treated with DPP-IV inhibitor sitagliptin. Grafts were analyzed for insulin production, β-cell proliferation and vascularization. In addition, the effect of sitagliptin on sprouting and Vascular Endothelial Growth Factor (VEGF)-A expression was examined ex vivo. The cAMP response element-binding (CREB) and VEGF-A/ Vascular Endothelial Growth Factor Receptor (VEGFR)-2 signaling pathway leading to islet vascularization was explored. Sitagliptin increased mean insulin content of islet grafts and area of insulin-positive tissue as well as β-cell proliferation. Interestingly, sitagliptin treatment also markedly increased endothelial cell proliferation, microvessel density and blood flow. Finally, GLP-1 (7-36) stimulated sprouting and VEGF expression, which was significantly enhanced by sitagliptin- mediated inhibition of DPP-IV. Our in vivo data demonstrate that sitagliptin treatment phosphorylated CREB and induced islet vascularization through VEGF-A/VEGFR-2 signaling pathway. This study paves a new pathway for improvement of islet transplantation in treating diabetes mellitus.
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Affiliation(s)
- Balaji Samikannu
- Third Medical Clinic and Policlinic, Justus-Liebig-University, Giessen, Germany
- * E-mail:
| | - Chunguang Chen
- CRTD / DFG- Center for Regenerative Therapies Dresden, Paul Langerhans Institut Dresden, Dresden, Germany
| | - Neelam Lingwal
- Third Medical Clinic and Policlinic, Justus-Liebig-University, Giessen, Germany
| | - Manju Padmasekar
- Third Medical Clinic and Policlinic, Justus-Liebig-University, Giessen, Germany
| | - Felix B. Engel
- University Hospital Erlangen, Experimental Renal and Cardiovascular Research, Nephropathology Division, Department of Pathology, Erlangen, Germany
| | - Thomas Linn
- Third Medical Clinic and Policlinic, Justus-Liebig-University, Giessen, Germany
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28
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Synergism of a natural plant product, oleanolic acid with calcineurin inhibitor in prolonging islet allograft survival. Transpl Immunol 2013; 29:64-70. [DOI: 10.1016/j.trim.2013.09.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 09/03/2013] [Accepted: 09/04/2013] [Indexed: 11/19/2022]
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29
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Paget MB, Murray HE, Bailey CJ, Downing R. Pre-transplant signal induction for vascularisation in human islets. Diab Vasc Dis Res 2013; 10:536-45. [PMID: 24062164 DOI: 10.1177/1479164113504770] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Human islet transplant success is partially impaired by slow revascularisation. Our study investigated the potential for rotational cell culture (RC) of human islets combined with thiazolidinedione (TZD) stimulation of peroxisome proliferator-activated receptor gamma (PPARγ) to upregulate vascular endothelial growth factor (VEGF) expression in the islets. Four groups of human islets were studied: static culture (SC) with and without 25 mmol/L TZD and RC with and without 25 mmol/L TZD. These were assessed for insulin secretion and soluble VEGF-A release. Both proteins were quantified by enzyme-linked immunosorbent assay (ELISA), supported with qualitative immunofluorescence staining. RC + TZD increased insulin secretion by >20% (p < 0.05-0.001) in response to 16.7 mmol/L glucose and 16.7 mmol/L glucose + 10 mmol/L theophylline (G + T). This effect was seen at all time intervals compared with SC and without addition of TZD. Soluble VEGF-A release was significantly augmented by RC and TZD exposure with an increased effect of >30% (p < 0.001) at 72 h under both SC and RC conditions. RC supplemented with a TZD enhances and prolongs the release of insulin and soluble VEGF-A by isolated human islets.
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Affiliation(s)
- Michelle B Paget
- Islet Research Laboratory, Worcestershire Clinical Research Unit, Worcestershire Acute Hospitals NHS Trust, Worcester, UK
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30
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Pre-culturing islets with mesenchymal stromal cells using a direct contact configuration is beneficial for transplantation outcome in diabetic mice. Cytotherapy 2013; 15:449-59. [DOI: 10.1016/j.jcyt.2012.11.008] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Revised: 10/23/2012] [Accepted: 11/19/2012] [Indexed: 12/17/2022]
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31
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Combined strategy of endothelial cells coating, Sertoli cells coculture and infusion improves vascularization and rejection protection of islet graft. PLoS One 2013; 8:e56696. [PMID: 23437215 PMCID: PMC3577699 DOI: 10.1371/journal.pone.0056696] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Accepted: 01/14/2013] [Indexed: 11/19/2022] Open
Abstract
Improving islet graft revascularization and inhibiting rejection become crucial tasks for prolonging islet graft survival. Endothelial cells (ECs) are the basis of islet vascularization and Sertoli cells (SCs) have the talent to provide nutritional support and exert immunosuppressive effects. We construct a combined strategy of ECs coating in the presence of nutritious and immune factors supplied by SCs in a co-culture system to investigate the effect of vascularization and rejection inhibition for islet graft. In vivo, the combined strategy improved the survival and vascularization as well as inhibited lymphocytes and inflammatory cytokines. In vitro, we found the combinatorial strategy improved the function of islets and the effect of ECs-coating on islets. Combined strategy treated islets revealed higher levels of anti-apoptotic signal molecules (Bcl-2 and HSP-32), survival and function related molecules (PDX-1, Ki-67, ERK1/2 and Akt) and demonstrated increased vascular endothelial growth factor receptor 2 (KDR) and angiogenesis signal molecules (FAk and PLC-γ). SCs effectively inhibited the activation of lymphocyte stimulated by islets and ECs. Predominantly immunosuppressive cytokines could be detected in culture supernatants of the SCs coculture group. These results suggest that ECs-coating and Sertoli cells co-culture or infusion synergistically enhance islet survival and function after transplantation.
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32
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Jung HS, Kim MJ, Hong SH, Lee YJ, Kang S, Lee H, Chung SS, Park JS, Park KS. The potential of endothelial colony-forming cells to improve early graft loss after intraportal islet transplantation. Cell Transplant 2013; 23:273-83. [PMID: 23294520 DOI: 10.3727/096368912x661364] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Early graft loss in islet transplantation means that a large amount of donor islets is required. Endothelial cells and endothelial colony-forming cells (ECFCs) have been reported to improve instant blood-mediated inflammatory reaction (IBMIR) in vitro. In this study, we examined if ECFC-coated porcine islets would prevent early graft loss in vivo. Human ECFCs were prepared from cord blood and cocultured with islets to make composite grafts. Diabetic nude mice underwent intraportal transplantation. Blood glucose levels were monitored, and morphological examination of the grafts along with analysis of the components of IBMIR and inflammatory reaction were performed with the liver tissues. The ECFC-coated islets significantly decreased blood glucose levels immediately after transplantation compared to the uncoated islets. Composite ECFC islet grafts were observed in the liver sections, associated with a more insulin(+) area compared to that of the uncoated group within 48 h after transplantation. Deposition of CD41a, C5b-9, and CD11b(+) cells was also decreased in the ECFC-coated group. Expression of porcine HMGB1 and mouse TNF-α was increased in the transplantated groups compared to the sham operation group, with a trend of a decreasing trend across the uncoated group, the ECFC-coated group, and the sham group. We demonstrated that the composite ECFC porcine islets transplanted into the portal vein of nude mice improved early graft loss and IBMIR in vivo.
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Affiliation(s)
- Hye Seung Jung
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
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33
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Abstract
BACKGROUND Transplanting pancreatic islets is of significant interest for type 1 diabetes mellitus. After intraportal injection of islets, inferior engraftment and eventual loss of transplanted islets constitute major limitations. Therefore, alternative approaches will be helpful. Here, we evaluated in animals whether an isolated venous sac would support survival of transplanted islets, along with correction of hyperglycemia. METHODS Pancreatic islets isolated from adult Lewis rats were transplanted either into an isolated venous sac made from lumbar vein or into the portal vein of syngeneic rats. The integrity and vascular organization of the venous sac was determined by studies of the local microcirculation. The engraftment, survival, and function of transplanted islets were analyzed by histology, including endocrine function in situ and by glycemic control in rats with streptozotocin-induced diabetes. RESULTS Transplanted islets showed normal morphology with insulin expression in isolated venous sac during the long term. Transplanted islets received blood supply from vasa vasorum and had access to drainage through venous tributaries in the venous sac. This resulted in restoration of euglycemia in diabetic rats. Removal of islet graft-bearing venous sac in diabetic rats led to recurrence of hyperglycemia. By contrast, euglycemia was not restored in rats treated by intraportal transplantation of islets. CONCLUSIONS We demonstrated that pancreatic islets successfully engrafted and functioned in the isolated venous sac with ability to restore euglycemia in diabetic rats. Therefore, the isolated venous sac offers a new site for transplantation of pancreatic islets. This would be clinically beneficial as an alternative to intrahepatic islet transplantation.
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Henriksnäs J, Lau J, Zang G, Berggren PO, Köhler M, Carlsson PO. Markedly decreased blood perfusion of pancreatic islets transplanted intraportally into the liver: disruption of islet integrity necessary for islet revascularization. Diabetes 2012; 61:665-73. [PMID: 22315321 PMCID: PMC3282819 DOI: 10.2337/db10-0895] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Experimental studies indicate low revascularization of intraportally transplanted islets. This study aimed to quantify, for the first time, the blood perfusion of intrahepatically transplanted islets and elucidate necessary factors for proper islet graft revascularization at this site. Yellow chameleon protein 3.0 islets expressing fluorescent protein in all cells were transplanted. Graft blood perfusion was determined by microspheres. The vascular density and relative contribution of donor blood vessels in revascularization was evaluated using islets expressing green fluorescent protein under the Tie-2 promoter. Blood perfusion of intrahepatic islets was as a mean only 5% of that of native islets at 1-month posttransplantation. However, there was a marked heterogeneity where blood perfusion was less decreased in islets transplanted without prior culture and in many cases restored in islets with disrupted integrity. Analysis of vascular density showed that distorted islets were well revascularized, whereas islets still intact at 1-month posttransplantation were almost avascular. Few donor endothelial cells were observed in the new islet vasculature. The very low blood perfusion of intraportally transplanted islets is likely to predispose for ischemia and hamper islet function. Since donor endothelial cells do not expand posttransplantation, disruption of islet integrity is necessary for revascularization to occur by recipient blood vessels.
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Affiliation(s)
| | - Joey Lau
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Guangxiang Zang
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Per-Olof Berggren
- Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, Stockholm, Sweden
| | - Martin Köhler
- Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, Stockholm, Sweden
| | - Per-Ola Carlsson
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
- Corresponding author: Per-Ola Carlsson,
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35
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Negi S, Jetha A, Aikin R, Hasilo C, Sladek R, Paraskevas S. Analysis of beta-cell gene expression reveals inflammatory signaling and evidence of dedifferentiation following human islet isolation and culture. PLoS One 2012; 7:e30415. [PMID: 22299040 PMCID: PMC3267725 DOI: 10.1371/journal.pone.0030415] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Accepted: 12/15/2011] [Indexed: 12/20/2022] Open
Abstract
The stresses encountered during islet isolation and culture may have deleterious effects on beta-cell physiology. However, the biological response of human islet cells to isolation remains poorly characterized. A better understanding of the network of signaling pathways induced by islet isolation and culturing may lead to strategies aimed at improving islet graft survival and function. Laser capture microdissection (LCM) was used to extract beta-cell RNA from 1) intact pancreatic islets, 2) freshly isolated islets, 3) islets cultured for 3 days, and changes in gene expression were examined by microarray analysis. We identified a strong inflammatory response induced by islet isolation that continues during in-vitro culture manifested by upregulation of several cytokines and cytokine-receptors. The most highly upregulated gene, interleukin-8 (IL-8), was induced by 3.6-fold following islet isolation and 56-fold after 3 days in culture. Immunofluorescence studies showed that the majority of IL-8 was produced by beta-cells themselves. We also observed that several pancreas-specific transcription factors were down-regulated in cultured islets. Concordantly, several pancreatic progenitor cell-specific transcription factors like SOX4, SOX9, and ID2 were upregulated in cultured islets, suggesting progressive transformation of mature beta-cell phenotype toward an immature endocrine cell phenotype. Our findings suggest islet isolation and culture induces an inflammatory response and loss of the mature endocrine cell phenotype. A better understanding of the signals required to maintain a mature beta-cell phenotype may help improve the efficacy of islet transplantation.
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Affiliation(s)
- Sarita Negi
- Human Islet Transplantation Laboratory, McGill University Health Centre, Montreal, Quebec, Canada
- Department of Surgery, McGill University, Montreal, Quebec, Canada
| | - Arif Jetha
- Human Islet Transplantation Laboratory, McGill University Health Centre, Montreal, Quebec, Canada
- Department of Surgery, McGill University, Montreal, Quebec, Canada
| | - Reid Aikin
- Human Islet Transplantation Laboratory, McGill University Health Centre, Montreal, Quebec, Canada
- Department of Surgery, McGill University, Montreal, Quebec, Canada
| | - Craig Hasilo
- Human Islet Transplantation Laboratory, McGill University Health Centre, Montreal, Quebec, Canada
- Department of Surgery, McGill University, Montreal, Quebec, Canada
| | - Rob Sladek
- McGill University and Genome Quebec Innovation Centre, Montreal, Quebec, Canada
| | - Steven Paraskevas
- Human Islet Transplantation Laboratory, McGill University Health Centre, Montreal, Quebec, Canada
- Department of Surgery, McGill University, Montreal, Quebec, Canada
- * E-mail:
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36
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Improving islet engraftment by gene therapy. J Transplant 2011; 2011:594851. [PMID: 22132301 PMCID: PMC3202131 DOI: 10.1155/2011/594851] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 08/22/2011] [Indexed: 11/18/2022] Open
Abstract
Islet cell transplantation is currently the only feasible long-term treatment option for patients with type 1 diabetes. However, the majority of transplanted islets experience damage and apoptosis during the isolation process, a blood-mediated inflammatory microenvironment in the portal vein upon islet infusion, hypoxia induced by the low oxygenated milieu, and poor-revascularization-mediated lack of nutrients, and impaired hormone modulation in the local transplanted site. Strategies using genetic modification methods through overexpression or silencing of those proteins involved in promoting new formation of blood vessels or inhibition of apoptosis may overcome these hurdles and improve islet engraftment outcomes.
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37
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Nyqvist D, Speier S, Rodriguez-Diaz R, Molano RD, Lipovsek S, Rupnik M, Dicker A, Ilegems E, Zahr-Akrawi E, Molina J, Lopez-Cabeza M, Villate S, Abdulreda MH, Ricordi C, Caicedo A, Pileggi A, Berggren PO. Donor islet endothelial cells in pancreatic islet revascularization. Diabetes 2011; 60:2571-7. [PMID: 21873551 PMCID: PMC3178280 DOI: 10.2337/db10-1711] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Freshly isolated pancreatic islets contain, in contrast to cultured islets, intraislet endothelial cells (ECs), which can contribute to the formation of functional blood vessels after transplantation. We have characterized how donor islet endothelial cells (DIECs) may contribute to the revascularization rate, vascular density, and endocrine graft function after transplantation of freshly isolated and cultured islets. RESEARCH DESIGN AND METHODS Freshly isolated and cultured islets were transplanted under the kidney capsule and into the anterior chamber of the eye. Intravital laser scanning microscopy was used to monitor the revascularization process and DIECs in intact grafts. The grafts' metabolic function was examined by reversal of diabetes, and the ultrastructural morphology by transmission electron microscopy. RESULTS DIECs significantly contributed to the vasculature of fresh islet grafts, assessed up to 5 months after transplantation, but were hardly detected in cultured islet grafts. Early participation of DIECs in the revascularization process correlated with a higher revascularization rate of freshly isolated islets compared with cultured islets. However, after complete revascularization, the vascular density was similar in the two groups, and host ECs gained morphological features resembling the endogenous islet vasculature. Surprisingly, grafts originating from cultured islets reversed diabetes more rapidly than those originating from fresh islets. CONCLUSIONS In summary, DIECs contributed to the revascularization of fresh, but not cultured, islets by participating in early processes of vessel formation and persisting in the vasculature over long periods of time. However, the DIECs did not increase the vascular density or improve the endocrine function of the grafts.
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Affiliation(s)
- Daniel Nyqvist
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, Stockholm, Sweden
- Corresponding authors: Per-Olof Berggren, , and Daniel Nyqvist,
| | - Stephan Speier
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, Stockholm, Sweden
| | - Rayner Rodriguez-Diaz
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, Florida
| | - R. Damaris Molano
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, Florida
| | - Saša Lipovsek
- Institute of Physiology, Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | - Marjan Rupnik
- Institute of Physiology, Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | - Andrea Dicker
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, Stockholm, Sweden
| | - Erwin Ilegems
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, Stockholm, Sweden
| | - Elsie Zahr-Akrawi
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, Florida
| | - Judith Molina
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, Florida
| | - Maite Lopez-Cabeza
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, Florida
| | - Susana Villate
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, Florida
| | - Midhat H. Abdulreda
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, Florida
| | - Camillo Ricordi
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, Stockholm, Sweden
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, Florida
| | - Alejandro Caicedo
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, Florida
| | - Antonello Pileggi
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, Florida
| | - Per-Olof Berggren
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, Stockholm, Sweden
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, Florida
- Division of Integrative Biosciences and Biotechnology, World Class University Program, Pohang University of Science and Technology, Pohang, Korea
- Corresponding authors: Per-Olof Berggren, , and Daniel Nyqvist,
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Cheng JYC, Raghunath M, Whitelock J, Poole-Warren L. Matrix components and scaffolds for sustained islet function. TISSUE ENGINEERING PART B-REVIEWS 2011; 17:235-47. [PMID: 21476869 DOI: 10.1089/ten.teb.2011.0004] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The clinical treatment of diabetes by islet transplantation is limited by low islet survival rates. A fundamental reason for this inefficiency is likely due to the removal of islets from their native environment. The isolation process not only disrupts interactions between blood vessels and endocrine cells, but also dramatically changes islet cell interaction with the extracellular matrix (ECM). Biomolecular cues from the ECM are important for islet survival, proliferation, and function; however, very little is known about the composition of islet ECM and the role each component plays. Without a thorough understanding of islet ECM, current endeavors to prolong islet survival via scaffold engineering lack a systematic basis. The following article reviews current knowledge of islet ECM and attempts to explain the roles they play in islet function. In addition, the effects of in vitro simulations of the native islet scaffold will be evaluated. Greater understanding in these areas will provide a preliminary platform from which a sustainable bioartificial pancreas may be developed.
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Affiliation(s)
- Jennifer Y C Cheng
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, Australia.
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Gupta R, Sefton MV. Application of an endothelialized modular construct for islet transplantation in syngeneic and allogeneic immunosuppressed rat models. Tissue Eng Part A 2011; 17:2005-15. [PMID: 21449709 DOI: 10.1089/ten.tea.2010.0542] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Modular tissue engineering is a novel approach to assemble tissues with an inherent vascularization. In this article, we evaluated whether endothelialized module-driven vascularization enhances islet engraftment in diabetic rats. Two thousand islets were transplanted in the omental pouch of syngeneic and allogeneic immunosuppressed diabetic recipients as free islets, islets in collagen modules, or islets in endothelialized modules. Transplantation of islets in endothelialized modules significantly increased the vessel density compared with controls. Donor green fluorescent protein-positive endothelial cells (ECs) formed vessels in proximity to transplanted islets; donor vessels connected to host vasculature as the vessels included erythrocytes in their lumens and were supported by host smooth muscle cells by 21 days. Transplantation of 2000 islets reversed diabetes in two of five of syngeneic recipients until 60 days, although there was no apparent benefit to islet function of adding ECs relative to collagen modules without EC. However, there was a trend toward increased viability when islets were implanted in endothelialized modules compared with collagen modules at 21 days. Meanwhile, 2000 islets in allogeneic immunosuppressed recipients lowered blood glucose levels short term, but there was graft failure within 1 week. This study explored the simultaneous transplantation of primary ECs with islets in diabetic recipients. The endothelialized modular approach increased vessel density around transplanted islets. Further modulation (i.e., acceleration) of vessel maturation, is presumed necessary to improve islet engraftment.
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Affiliation(s)
- Rohini Gupta
- Institute of Biomaterials and Biomedical Engineering and Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Canada
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40
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Park K, Shim E, Choi B, Moon C, Kim S, Kim Y, Kwon C, Joh J, Koh G, Kim S. Cartilage Oligomeric Matrix Protein–Angiopoientin-1 Enhances Angiogenesis of Isolated Islet and Maintains Normoglycemia Following Transplantation. Transplant Proc 2010; 42:2653-7. [DOI: 10.1016/j.transproceed.2010.04.048] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 12/08/2009] [Accepted: 04/08/2010] [Indexed: 11/25/2022]
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Shimoda M, Chen S, Noguchi H, Matsumoto S, Grayburn PA. In vivo non-viral gene delivery of human vascular endothelial growth factor improves revascularisation and restoration of euglycaemia after human islet transplantation into mouse liver. Diabetologia 2010; 53:1669-79. [PMID: 20405100 PMCID: PMC3804430 DOI: 10.1007/s00125-010-1745-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2010] [Accepted: 03/03/2010] [Indexed: 10/19/2022]
Abstract
AIMS/HYPOTHESIS Delivery of the gene for human vascular endothelial growth factor (VEGF, also known as VEGFA) to both the transplanted islets and the surrounding tissue may promote islet revascularisation and survival. We previously showed the effective delivery of VEGF gene to rat myocardium by an ultrasound-mediated gene-transfer method named ultrasound-targeted microbubble destruction (UTMD). Here we examined the effect of non-viral VEGF delivery using UTMD on transplanted islets in vivo. METHODS A marginal number of human islets were transplanted into livers of mice which were a model for diabetes. Then, non-viral plasmid vectors encoding VEGF (VEGF group, n = 11) or the gene for green fluorescent protein (GFP) (GFP group, n = 7) were introduced into the host liver by UTMD. Transplantation without gene delivery was performed as a control (no-UTMD group, n = 8). Blood glucose, serum human insulin, C-peptide levels and the revascularisation in graft islets were evaluated. RESULTS Restoration of euglycaemia occurred in 13% in the no-UTMD group and 14% in the GFP group, whereas 73% mice in the VEGF group became euglycaemic at day 30 (p < 0.05 in no-UTMD vs VEGF). Serum human insulin and C-peptide were significantly higher in the VEGF group at day 32 (insulin: no-UTMD, 17 +/- 8; GFP, 37 +/- 17; VEGF, 109 +/- 26 pmol/l, respectively, p < 0.05; C-peptide: no-UTMD, 68 +/- 38; GFP, 115 +/- 58; VEGF, 791 +/- 230 pmol/l, respectively, p < 0.05). Vessel density in graft islets was significantly higher in the VEGF group (no-UTMD, 169 +/- 36; GFP, 227 +/- 39; VEGF, 649 +/- 51 counts/mm(2), respectively, p < 0.05). CONCLUSIONS/INTERPRETATION Delivery of VEGF gene to host liver using UTMD promoted islet revascularisation after islet transplantation and improved the restoration of euglycaemia.
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Affiliation(s)
- M. Shimoda
- Division of Cardiology, Department of Internal Medicine, Baylor, University Medical Center, Baylor Heart and Vascular Institute, 621 North Hall St, Suite H030, Dallas, TX 75226, USA, Baylor Heart and Vascular Institute, 621 North Hall St, Suite H030, Dallas, TX 75226, USA
| | - S. Chen
- Division of Cardiology, Department of Internal Medicine, Baylor, University Medical Center, Baylor Heart and Vascular Institute, 621 North Hall St, Suite H030, Dallas, TX 75226, USA
| | - H. Noguchi
- Baylor Heart and Vascular Institute, 621 North Hall St, Suite H030, Dallas, TX 75226, USA
| | - S. Matsumoto
- Baylor Heart and Vascular Institute,, 621 North Hall St, Suite H030,, Dallas, TX 75226, USA
| | - P. A. Grayburn
- Division of Cardiology, Department of Internal Medicine, Baylor, University Medical Center, Baylor Heart and Vascular Institute, 621 North Hall St, Suite H030, Dallas, TX 75226, USA
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Chow LW, Wang LJ, Kaufman DB, Stupp SI. Self-assembling nanostructures to deliver angiogenic factors to pancreatic islets. Biomaterials 2010; 31:6154-61. [PMID: 20552727 PMCID: PMC2965796 DOI: 10.1016/j.biomaterials.2010.04.002] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Supramolecular self-assembly of nanoscale filaments offers a vehicle to signal cells within dense cell aggregates such as pancreatic islets. We previously developed a heparin-binding peptide amphiphile (HBPA) that self-assembles into nanofiber gels at concentrations of 1% by weight when mixed with heparin and activates heparin-binding, angiogenic growth factors. We report here on the use of these molecules at concentrations 100 times lower to drive delivery of the nanofibers into the dense islet interior. Using fluorescent markers, HBPA molecules, heparin, and FGF2 were shown to be present in and on the surface of murine islets. The intraislet nanofibers were found to be necessary to retain FGF2 within the islet for 48 h and to increase cell viability significantly for at least 7 days in culture. Furthermore, enhanced insulin secretion was observed with the nanofibers for 3 days in culture. Delivery of FGF2 and VEGF in conjunction with the HBPA/heparin nanofibers also induced a significant amount of islet endothelial cell sprouting from the islets into a peptide amphiphile 3-D matrix. We believe the infiltration of bioactive nanofibers in the interior of islets as an artificial ECM can improve cell viability and function in vitro and enhance their vascularization in the presence of growth factors such as FGF2 and VEGF. The approach described here may have significant impact on islet transplantation to treat type 1 diabetes.
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Affiliation(s)
- Lesley W. Chow
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, United States
| | - Ling-jia Wang
- Department of Surgery, Division of Organ Transplantation, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, United States
| | - Dixon B. Kaufman
- Department of Surgery, Division of Organ Transplantation, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, United States
- Institute for BioNanotechnology in Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, United States
| | - Samuel I. Stupp
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, United States
- Institute for BioNanotechnology in Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, United States
- Department of Chemistry, Northwestern University, Evanston, IL 60208, United States
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, United States
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Richards OC, Raines SM, Attie AD. The role of blood vessels, endothelial cells, and vascular pericytes in insulin secretion and peripheral insulin action. Endocr Rev 2010; 31:343-63. [PMID: 20164242 PMCID: PMC3365844 DOI: 10.1210/er.2009-0035] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Accepted: 12/17/2009] [Indexed: 02/08/2023]
Abstract
The pathogenesis of type 2 diabetes is intimately intertwined with the vasculature. Insulin must efficiently enter the bloodstream from pancreatic beta-cells, circulate throughout the body, and efficiently exit the bloodstream to reach target tissues and mediate its effects. Defects in the vasculature of pancreatic islets can lead to diabetic phenotypes. Similarly, insulin resistance is accompanied by defects in the vasculature of skeletal muscle, which ultimately reduce the ability of insulin and nutrients to reach myocytes. An underappreciated participant in these processes is the vascular pericyte. Pericytes, the smooth muscle-like cells lining the outsides of blood vessels throughout the body, have not been directly implicated in insulin secretion or peripheral insulin delivery. Here, we review the role of the vasculature in insulin secretion, islet function, and peripheral insulin delivery, and highlight a potential role for the vascular pericyte in these processes.
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Affiliation(s)
- Oliver C Richards
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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Johansson A, Olerud J, Johansson M, Carlsson PO. Angiostatic factors normally restrict islet endothelial cell proliferation and migration: implications for islet transplantation. Transpl Int 2010; 22:1182-8. [PMID: 19891047 DOI: 10.1111/j.1432-2277.2009.00939.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
New blood vessel formation in transplanted islets occurs within 7-14 days post-transplantation through both the expansion of donor islet endothelium and ingrowth of blood vessels from the implantation organ. However, several studies indicate that although the islets attract recipient blood vessels, the formed intra-islet vascular network is insufficient, which affects islet post-transplant function. This study aimed to develop an in vitro model to investigate the migration and proliferation properties of isolated liver and islet endothelium.Rat islet or liver endothelium was purified using Bandeiraea simplicifolia(BS-1)-coated Dynabeads. The liver endothelium displayed an increased migration and proliferation to islet-conditioned medium. These effects were fully prevented by adding a neutralizing vascular endothelial growth factor (VEGF)-antibody. In contrast, islet-produced VEGF failed to induce islet endothelial cell migration and only had marginal effects on islet endothelial cell proliferation.These properties could, however, be activated through blocking the effects of either endostatin, thrombospondin-1 or alpha(1)-antitrypsin. In conclusion, VEGF may attract recipient blood vessels towards intrahepatically transplanted islets,but intra-islet vascular expansion is hampered by angiostatic factors present within the islets and the islet endothelium. Inhibition of angiostatic factors early after transplantation may provide a strategy to restore the islet vascular network and improve islet graft function.
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Affiliation(s)
- Asa Johansson
- Department of Medical Cell Biology, Uppsala University, Husargatan 3, Box 571, SE-751 23 Uppsala, Sweden.
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Kim HI, Yu JE, Lee SY, Sul AY, Jang MS, Rashid MA, Park SG, Kim SJ, Park CG, Kim JH, Park KS. The effect of composite pig islet-human endothelial cell grafts on the instant blood-mediated inflammatory reaction. Cell Transplant 2009; 18:31-7. [PMID: 19476207 DOI: 10.3727/096368909788237113] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Instant blood-mediated inflammatory reaction (IBMIR) causes rapid islet loss in portal vein islet transplantation. Endothelial cells are known to protect against complement-mediated lysis and activation of coagulation. We tested composite pig islet-human endothelial cell grafts as a strategy to overcome IBMIR. Porcine islets were cocultured with human endothelial cells in specially modified culture medium composed of M199 and M200 for 1-9 days. A positive control group, negative control group, and the endothelial cell-coated group were examined with an in vitro tubing loop assay using human blood. The endothelial cell-coated group was subdivided and analyzed by degree of surface coverage by endothelial cells (< or = 50% vs. > 50%) or coculture time (< 5 days vs. > or = 5 days). Platelet consumption and complement and coagulation activation were assessed by platelet count, C3a, and thrombin-antithrombin complex (TAT), respectively. After 60-min incubation in human blood, the endothelial cell-coated group showed platelet consumption inhibition and low C3a and TAT assay results compared to uncoated controls. When the endothelial cell-coated group was subdivided by degree of surface coverage, the < or = 50% coated group showed less platelet consumption and less activation of complement and coagulation compared with the positive control (uncoated) group. On analysis by coculture time, only the subgroup cocultured for < 5 days showed the same protective effect. Human endothelial cell-coated pig islets, especially the partially coated and short-term cocultured pig islet-human endothelial cell composites, reduced all components of IBMIR. If the optimal endothelial cell-islet coculture method could be identified, human endothelial cell coating of pig islets would offer new strategies to improve xenogenic islet transplantation outcomes.
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Affiliation(s)
- Hyoung-Il Kim
- Xenotransplantation Research Center, Seoul 110-744, Republic of Korea
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Lau J, Kampf C, Mattsson G, Nyqvist D, Köhler M, Berggren PO, Carlsson PO. Beneficial role of pancreatic microenvironment for angiogenesis in transplanted pancreatic islets. Cell Transplant 2009; 18:23-30. [PMID: 19476206 DOI: 10.3727/096368909788237131] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Pancreatic islets implanted heterotopically (i.e., into the kidney, spleen, or liver) become poorly revascularized following transplantation. We hypothesized that islets implanted into the pancreas would become better revascularized. Islets isolated from transgenic mice expressing enhanced yellow fluorescent protein (EYFP) in all somatic cells were cultured before they were implanted into the pancreas or beneath the renal capsule of athymic mice. Vascular density was evaluated in histological sections 1 month posttransplantation. EYFP was used as reporter for the transgene to identify the transplanted islets. Islet endothelial cells were visualized by staining with the lectin Bandeiraea simplicifolia (BS-1). Capillary numbers in intrapancreatically implanted islets were only slightly lower than those counted in endogenous islets, whereas islets implanted beneath the renal capsule had a markedly lower vascular density. In order to determine if this high graft vascular density at the intrapancreatic site reflected expansion of remnant donor endothelial cells or increased ingrowth of blood vessels from the host, also islets from Tie2-green fluorescent protein (GFP) mice (i.e., islets with fluorescent endothelial cells) were transplanted into the pancreas or beneath the renal capsule of athymic mice. These islet grafts revealed that the new vascular structures formed in the islet grafts contained very few GFP-positive cells, and thus mainly were of recipient origin. The reason(s) for the much better ingrowth of blood vessels at the intrapancreatic site merits further studies, because this may help us form strategies to overcome the barrier for ingrowth of host vessels also into islets in heterotopic implantation sites.
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Affiliation(s)
- Joey Lau
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden.
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Abstract
Pancreatic islets are highly vascularized micro-organs. Approximately 10% of an islet consists of blood vessels. The induction and maintenance of the islet vascular system depend on VEGF secreted from β-cells. VEGF is also critical for the phenotype of the islet vasculature by induction of a vast number of fenestrae. The islet vasculature serves the role of supplying the endocrine cells with oxygen and nutrients, but may also be important for proper glucose sensing of the cells, for paracrine support of endocrine function and growth, and for drainage of metabolites and secreted islet hormones into the systemic circulation. Emerging evidence suggests an important role of islet endothelial cells to maintain β-cell function and growth by secretion of molecules such as hepatocyte growth factor, thrombospondin-1 and laminins, thereby forming a vascular niche for the endocrine cells.
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Affiliation(s)
- Johan Olerud
- a Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Åsa Johansson
- a Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Per-Ola Carlsson
- b Department of Medical Sciences, Section for Endocrinology and Diabetology, Uppsala University Hospital, Uppsala, Sweden and Department of Medical Cell Biology, Husargatan 3, Box 571, SE-75123, Uppsala, Sweden.
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Chen C, Kuehn C, Bretzel RG, Linn T. Anti-inflammatory thalidomide improves islet grafts survival and functions in a xenogenic environment. PLoS One 2009; 4:e6312. [PMID: 19617916 PMCID: PMC2708353 DOI: 10.1371/journal.pone.0006312] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2009] [Accepted: 06/10/2009] [Indexed: 12/14/2022] Open
Abstract
Thalidomide possesses both anti-inflammatory and anti-angiogenic properties. This study investigates its potential application in islet transplantation with a xenogenic transplantation model. Transplantation was performed using C57Bl/6 mice and NMRI nu/nu mice as recipients of porcine islets. Moreover, islet graft vasculature and inflammation were investigated to identify the mechanisms of thalidomide action. In the immunocompetent environment of C57Bl/6 mice, a fast graft rejection was observed. The group treated with thalidomide 200 mg/kg BW per day achieved and maintained euglycemia in the complete observation period for 42 days. The treated mice had more functional islet graft mass with less leukocyte infiltration. The pro-inflammatory TNF-α and VEGF content in islet grafted kidneys was significantly lowered by the treatment. By comparison, thalidomide was not effective in improving graft survival in immunocompromised nude mice. It strongly inhibited the VEGF and TNF-α-induced endothelial proliferation of isolated pig islets in a dose dependent manner. The magnitude of thalidomide's inhibitory effect was nearly identical to the effect of VEGF- receptor 2 inhibitor SU416 and anti-TNF-receptor 1 neutralizing antibody, and was reversed by sphingosine-1-phosphate. In conclusion, the anti-inflammatory effect of thalidomide improved islet graft survival and function in a transplantation model with a maximum immune barrier.
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Affiliation(s)
- Chunguang Chen
- Medical Clinic and Policlinic 3, Justus-Liebig University Giessen, Giessen, Germany
| | - Carina Kuehn
- Medical Clinic and Policlinic 3, Justus-Liebig University Giessen, Giessen, Germany
| | - Reinhard G. Bretzel
- Medical Clinic and Policlinic 3, Justus-Liebig University Giessen, Giessen, Germany
| | - Thomas Linn
- Medical Clinic and Policlinic 3, Justus-Liebig University Giessen, Giessen, Germany
- * E-mail:
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49
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Iken M, Brandhorst H, Korsgren O, Brandhorst D. Pig pancreas oxygenation at 20 degrees C increases islet ATP generation but deteriorates islet function. Cell Transplant 2009; 18:745-51. [PMID: 19520045 DOI: 10.3727/096368909x470838] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Successful pancreas preservation during storage in oxygenated perfluorodecalin (PFD) is mainly related to oxidative ATP generation during storage. Increasing the storage temperature would accelerate this process essential for resuscitation of ischemically damaged pancreatic tissue. The present study aimed at comparing islet isolation outcome from adult pig pancreata preserved in oxygenated PFD by means of a one-layer method during storage on ice or at 20 degrees C. Resected pancreata were intraductally flushed with cold UW solution and promptly processed (n = 6) or stored for 3 h in continuously oxygenated PFD at 4 degrees C (n = 5) or 20 degrees C (n = 7). Prior to digestion-filtration pancreata were intraductally injected with UW supplemented with Serva collagenase NB8 and neutral protease. Islet quality assessment determined viability, glucose stimulation index, mitochondrial activity, intracellular ATP content, and transplant function in diabetic nude mice. Pancreata oxygenated for 3 h at 20 degrees C yielded islet numbers similar to organs oxygenated at 4 degrees C. Compared to a storage temperature of 20 degrees C, preservation at 4 degrees C reduced islet ATP content (p < 0.05) as well as islet viability (p < 0.05). Nevertheless, PFD storage at 20 degrees C decreased insulin response to glucose compared to unstored pancreata (p < 0.05). In contrast to unstored pancreata or cold-stored organs, transplantation of islets isolated after oxygenation at 20 degrees C was characterized by an early loss of transplant function in 50% of recipients (p < 0.05). The present study demonstrates that PFD storage at 20 degrees C enhances islet ATP synthesis within a short period of oxygenation but deteriorates islet function. We conclude that the present data reflect an equilibration between reduced depression of metabolic activity resulting in damage of islets and temperature-stimulated acceleration of ATP synthesis. Future studies are required to adjust the optimum storage temperature for pancreas oxygenation in different species.
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Affiliation(s)
- M Iken
- Department of Gastroenterology, Hepatology & Endocrinology, Medical School, Hanover, Germany
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50
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Johansson M, Olerud J, Jansson L, Carlsson PO. Prolactin treatment improves engraftment and function of transplanted pancreatic islets. Endocrinology 2009; 150:1646-53. [PMID: 19095742 DOI: 10.1210/en.2008-1318] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Transplantation of pancreatic islets is clinically used to treat type 1 diabetes but requires multiple donors. Previous experimental studies demonstrated that transplanted islets have a low blood vessel density, which leads to a hypoxic microenvironment. The present study tested the hypothesis that experimental prolactin pretreatment, a substance that seems to stimulate angiogenesis in endogenous islets, would increase graft blood vessel density, thereby improving transplantation outcome. Pancreatic islets from C57BL/6 mice were incubated with prolactin (500 ng/ml) or vehicle during the last 24 h of culture before syngeneic transplantation beneath the renal capsule, or recipients were injected with prolactin or vehicle for the first 7 d after transplantation. One month after transplantation, graft vascular density, blood flow, oxygen tension, endocrine volume, and function were evaluated. Also, human islets were incubated with prolactin or vehicle before experimental transplantation and investigated for vascular engraftment. Vascular engraftment of syngeneically transplanted mouse islets was improved by both in vivo and in vitro prolactin pretreatment. Moreover, prolactin pretreatment in vitro of islets used for transplantation improved recovery from diabetes in a minimal islet mass model. Interestingly, also human islets subjected to prolactin treatment before experimental transplantation demonstrated improved revascularization, blood perfusion, and oxygen tension when evaluated 1 month after transplantation. We conclude that prolactin may improve engraftment of transplanted pancreatic islets. The protocol with pretreatment of islets ex vivo could minimize the risk of side effects when used in the clinical setting.
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Affiliation(s)
- Magnus Johansson
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
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