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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: 10] [Impact Index Per Article: 5.0] [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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Safley SA, Barber GF, Holdcraft RW, Gazda LS, Duncanson S, Poznansky MC, Sambanis A, Weber CJ. Multiple clinically relevant immunotherapies prolong the function of microencapsulated porcine islet xenografts in diabetic NOD mice without the use of anti‐CD154 mAb. Xenotransplantation 2020; 27:e12577. [DOI: 10.1111/xen.12577] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 12/06/2019] [Accepted: 12/09/2019] [Indexed: 11/28/2022]
Affiliation(s)
- Susan A. Safley
- Department of Surgery Emory University School of Medicine Atlanta GA
| | - Graham F. Barber
- Department of Surgery Emory University School of Medicine Atlanta GA
- Parker H. Petit Institute of Bioengineering and Bioscience Georgia Institute of Technology Atlanta GA
| | | | | | - Stephanie Duncanson
- School of Chemical & Biomolecular Engineering Department of Biomedical Engineering Georgia Institute of Technology Atlanta GA
- Oncorus Cambridge MA
| | - Mark C. Poznansky
- Vaccine and Immunotherapy Center Massachusetts General Hospital (East) Charlestown MA
| | - Athanassios Sambanis
- School of Chemical & Biomolecular Engineering Department of Biomedical Engineering Georgia Institute of Technology Atlanta GA
- W. M. Keck Foundation Los Angeles CA
| | - Collin J. Weber
- Department of Surgery Emory University School of Medicine Atlanta GA
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3
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White AM, Shamul JG, Xu J, Stewart S, Bromberg JS, He X. Engineering Strategies to Improve Islet Transplantation for Type 1 Diabetes Therapy. ACS Biomater Sci Eng 2019; 6:2543-2562. [PMID: 33299929 DOI: 10.1021/acsbiomaterials.9b01406] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Type 1 diabetes is an autoimmune disease in which the immune system attacks insulin-producing beta cells of pancreatic islets. Type 1 diabetes can be treated with islet transplantation; however, patients must be administered immunosuppressants to prevent immune rejection of the transplanted islets if they are not autologous or not engineered with immune protection/isolation. To overcome biological barriers of islet transplantation, encapsulation strategies have been developed and robustly investigated. While islet encapsulation can prevent the need for immunosuppressants, these approaches have not shown much success in clinical trials due to a lack of long-term insulin production. Multiple engineering strategies have been used to improve encapsulation and post-transplantation islet survival. In addition, more efficient islet cryopreservation methods have been designed to facilitate the scaling-up of islet transplantation. Other islet sources have been identified including porcine islets and stem cell-derived islet-like aggregates. Overall, islet-laden capsule transplantation has greatly improved over the past 30 years and is moving towards becoming a clinically feasible treatment for type 1 diabetes.
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Affiliation(s)
- Alisa M White
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA
| | - James G Shamul
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA
| | - Jiangsheng Xu
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA
| | - Samantha Stewart
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA
| | - Jonathan S Bromberg
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD 21201.,Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201.,Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, MD 21201.,Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, MD 21201
| | - Xiaoming He
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.,Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, MD 21201.,Robert E. Fischell Institute for Biomedical Devices, University of Maryland, College Park, MD 20742, USA, Baltimore, MD 21201, USA
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Stabler CL, Li Y, Stewart JM, Keselowsky BG. Engineering immunomodulatory biomaterials for type 1 diabetes. NATURE REVIEWS. MATERIALS 2019; 4:429-450. [PMID: 32617176 PMCID: PMC7332200 DOI: 10.1038/s41578-019-0112-5] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
A cure for type 1 diabetes (T1D) would help millions of people worldwide, but remains elusive thus far. Tolerogenic vaccines and beta cell replacement therapy are complementary therapies that seek to address aberrant T1D autoimmune attack and subsequent beta cell loss. However, both approaches require some form of systematic immunosuppression, imparting risks to the patient. Biomaterials-based tools enable localized and targeted immunomodulation, and biomaterial properties can be designed and combined with immunomodulatory agents to locally instruct specific immune responses. In this Review, we discuss immunomodulatory biomaterial platforms for the development of T1D tolerogenic vaccines and beta cell replacement devices. We investigate nano- and microparticles for the delivery of tolerogenic agents and autoantigens, and as artificial antigen presenting cells, and highlight how bulk biomaterials can be used to provide immune tolerance. We examine biomaterials for drug delivery and as immunoisolation devices for cell therapy and islet transplantation, and explore synergies with other fields for the development of new T1D treatment strategies.
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Affiliation(s)
- CL Stabler
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
- Interdisciplinary Graduate Program in Biomedical Sciences, University of Florida, Gainesville, FL, USA
- University of Florida Diabetes Institute, Gainesville, FL, USA
| | - Y Li
- Interdisciplinary Graduate Program in Biomedical Sciences, University of Florida, Gainesville, FL, USA
| | - JM Stewart
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - BG Keselowsky
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
- Interdisciplinary Graduate Program in Biomedical Sciences, University of Florida, Gainesville, FL, USA
- University of Florida Diabetes Institute, Gainesville, FL, USA
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Song S, Roy S. Progress and challenges in macroencapsulation approaches for type 1 diabetes (T1D) treatment: Cells, biomaterials, and devices. Biotechnol Bioeng 2016; 113:1381-402. [PMID: 26615050 DOI: 10.1002/bit.25895] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 10/30/2015] [Accepted: 11/24/2015] [Indexed: 12/15/2022]
Abstract
Macroencapsulation technology has been an attractive topic in the field of treatment for Type 1 diabetes due to mechanical stability, versatility, and retrievability of the macro-capsule design. Macro-capsules can be categorized into extravascular and intravascular devices, in which solute transport relies either on diffusion or convection, respectively. Failure of macroencapsulation strategies can be due to limited regenerative capacity of the encased insulin-producing cells, sub-optimal performance of encapsulation biomaterials, insufficient immunoisolation, excessive blood thrombosis for vascular perfusion devices, and inadequate modes of mass transfer to support cell viability and function. However, significant technical advancements have been achieved in macroencapsulation technology, namely reducing diffusion distance for oxygen and nutrients, using pro-angiogenic factors to increase vascularization for islet engraftment, and optimizing membrane permeability and selectivity to prevent immune attacks from host's body. This review presents an overview of existing macroencapsulation devices and discusses the advances based on tissue-engineering approaches that will stimulate future research and development of macroencapsulation technology. Biotechnol. Bioeng. 2016;113: 1381-1402. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Shang Song
- Department of Bioengineering and Therapeutic Sciences, University of California-San Francisco, San Francisco, California 94158
| | - Shuvo Roy
- Department of Bioengineering and Therapeutic Sciences, University of California-San Francisco, San Francisco, California 94158.
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Perez RA, Kim HW. Core-shell designed scaffolds for drug delivery and tissue engineering. Acta Biomater 2015; 21:2-19. [PMID: 25792279 DOI: 10.1016/j.actbio.2015.03.013] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 03/03/2015] [Accepted: 03/08/2015] [Indexed: 11/19/2022]
Abstract
Scaffolds that secure and deliver therapeutic ingredients like signaling molecules and stem cells hold great promise for drug delivery and tissue engineering. Employing a core-shell design for scaffolds provides a promising solution. Some unique methods, such as co-concentric nozzle extrusion, microfluidics generation, and chemical confinement reactions, have been successful in producing core-shelled nano/microfibers and nano/microspheres. Signaling molecules and drugs, spatially allocated to the core and/or shell part, can be delivered in a controllable and sequential manner for optimal therapeutic effects. Stem cells can be loaded within the core part on-demand, safely protected from the environments, which ultimately affords ex vivo culture and in vivo tissue engineering. The encapsulated cells experience three-dimensional tissue-mimic microenvironments in which therapeutic molecules are secreted to the surrounding tissues through the semi-permeable shell. Tuning the material properties of the core and shell, changing the geometrical parameters, and shaping them into proper forms significantly influence the release behaviors of biomolecules and the fate of the cells. This topical issue highlights the immense usefulness of core-shell designs for the therapeutic actions of scaffolds in the delivery of signaling molecules and stem cells for tissue regeneration and disease treatment.
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Affiliation(s)
- Roman A Perez
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan 330-714, Republic of Korea; Department of Nanobiomedical Science & BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan 330-714, Republic of Korea
| | - Hae-Won Kim
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan 330-714, Republic of Korea; Department of Nanobiomedical Science & BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan 330-714, Republic of Korea; Department of Biomaterials Science, College of Dentistry, Dankook University, Cheonan 330-714, Republic of Korea.
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7
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Denner J, Graham M. Xenotransplantation of islet cells: what can the non-human primate model bring for the evaluation of efficacy and safety? Xenotransplantation 2015; 22:231-5. [DOI: 10.1111/xen.12169] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
| | - Melanie Graham
- Department of Surgery; Preclinical Research Center; University of Minnesota; Saint Paul MN USA
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Ma M, Chiu A, Sahay G, Doloff JC, Dholakia N, Thakrar R, Cohen J, Vegas A, Chen D, Bratlie KM, Dang T, York RL, Hollister-Lock J, Weir GC, Anderson DG. Core-shell hydrogel microcapsules for improved islets encapsulation. Adv Healthc Mater 2013; 2:667-72. [PMID: 23208618 PMCID: PMC3814167 DOI: 10.1002/adhm.201200341] [Citation(s) in RCA: 115] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Indexed: 12/22/2022]
Abstract
Islets microencapsulation holds great promise to treat type 1 diabetes. Currently used alginate microcapsules often have islets protruding outside capsules, leading to inadequate immuno-protection. A novel design of microcapsules with core-shell structures using a two-fluid co-axial electro-jetting is reported. Improved encapsulation and diabetes correction is achieved in a single step by simply confining the islets in the core region of the capsules.
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Affiliation(s)
- Minglin Ma
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
- Department of Anesthesiology, Children Hospital Boston, 300 Longwood Ave, Boston, MA 02115, USA
| | - Alan Chiu
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
- Department of Anesthesiology, Children Hospital Boston, 300 Longwood Ave, Boston, MA 02115, USA
| | - Gaurav Sahay
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Joshua C. Doloff
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
- Department of Anesthesiology, Children Hospital Boston, 300 Longwood Ave, Boston, MA 02115, USA
| | - Nimit Dholakia
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
- Department of Anesthesiology, Children Hospital Boston, 300 Longwood Ave, Boston, MA 02115, USA
| | - Raj Thakrar
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
- Department of Anesthesiology, Children Hospital Boston, 300 Longwood Ave, Boston, MA 02115, USA
| | - Joshua Cohen
- Section on Islet Cell and Regenerative Biology, Research Division, Joslin Diabetes Center, One Joslin Place, Boston, MA 02215, USA
| | - Arturo Vegas
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
- Department of Anesthesiology, Children Hospital Boston, 300 Longwood Ave, Boston, MA 02115, USA
| | - Delai Chen
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
- Department of Anesthesiology, Children Hospital Boston, 300 Longwood Ave, Boston, MA 02115, USA
| | - Kaitlin M. Bratlie
- Departments of Materials Science & Engineering and Chemical & Biological Engineering, Iowa State University, Ames, IA, 50011
| | - Tram Dang
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
- Department of Anesthesiology, Children Hospital Boston, 300 Longwood Ave, Boston, MA 02115, USA
| | - Roger L. York
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
- Department of Anesthesiology, Children Hospital Boston, 300 Longwood Ave, Boston, MA 02115, USA
| | - Jennifer Hollister-Lock
- Section on Islet Cell and Regenerative Biology, Research Division, Joslin Diabetes Center, One Joslin Place, Boston, MA 02215, USA
| | - Gordon C. Weir
- Section on Islet Cell and Regenerative Biology, Research Division, Joslin Diabetes Center, One Joslin Place, Boston, MA 02215, USA
| | - Daniel G. Anderson
- David H Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
- Division of Health Science Technology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
- Department of Anesthesiology, Children Hospital Boston, 300 Longwood Ave, Boston, MA 02115, USA
- Section on Islet Cell and Regenerative Biology, Research Division, Joslin Diabetes Center, One Joslin Place, Boston, MA 02215, USA
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Souza YEDMD, Chaib E, Lacerda PGDD, Crescenzi A, Bernal-Filho A, D'Albuquerque LAC. Islet transplantation in rodents. Do encapsulated islets really work? ARQUIVOS DE GASTROENTEROLOGIA 2012; 48:146-52. [PMID: 21709957 DOI: 10.1590/s0004-28032011000200011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Accepted: 11/19/2010] [Indexed: 11/22/2022]
Abstract
CONTEXT Diabetes mellitus type I affects around 240 million people in the world and only in the USA 7.8% of the population. It has been estimated that the costs of its complications account for 5% to 10% of the total healthcare spending around the world. According to World Health Organization, 300 million people are expected to develop diabetes mellitus by the year 2025. The pancreatic islet transplantation is expected to be less invasive than a pancreas transplant, which is currently the most commonly used approach. OBJECTIVES To compare the encapsulated and free islet transplantation in rodents looking at sites of islet implantation, number of injected islets, viability and immunosuppression. METHODS A literature search was conducted using MEDLINE/PUBMED and SCIELO with terms about islet transplantation in the rodent from 2000 to 2010. We found 2,636 articles but only 56 articles from 2000 to 2010 were selected. RESULTS In these 56 articles used, 34% were encapsulated and 66% were nonencapsulated islets. Analyzing both types of islets transplantation, the majority of the encapsulated islets were implanted into the peritoneal cavity and the nonencapsulated islets into the liver, through the portal vein. In addition, the great advantage of the peritoneal cavity as the site of islet transplantation is its blood supply. Both vascular endothelial cells and vascular endothelial growth factor were used to stimulate angiogenesis of the islet grafts, increasing the vascularization rapidly after implantation. It also has been proven that there is influence of the capsules, since the larger the capsule more chances there are of central necrosis. In some articles, the use of immunosuppression demonstrated to increase the life expectancy of the graft. CONCLUSION While significant progress has been made in the islets transplantation field, many obstacles remain to be overcome. Microencapsulation provides a means to transplant islets without immunosuppressive agents and may enable the performance of xenotransplantation. The use of alternative donor sources, fewer islets per capsule and the appropriate deployment location, such as the peritoneal cavity, may give a future perspective to the application of immunoprotective capsules and viability in clinical practice. A variety of strategies, such as genetic engineering, co-encapsulation, improvement in oxygen supply or the establishment of hypoxia resistance will also improve the islet transplantation performance. It remains to be determined which combination of strategies with encapsulation can fulfill the promise of establishing a simple and safe transplantation as a cure for diabetes.
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Goh F, Sambanis A. In vivo noninvasive monitoring of dissolved oxygen concentration within an implanted tissue-engineered pancreatic construct. Tissue Eng Part C Methods 2011; 17:887-94. [PMID: 21486202 DOI: 10.1089/ten.tec.2011.0098] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The function of an implanted tissue-engineered pancreatic construct is influenced by many in vivo factors; however, assessing its function is based primarily on end physiologic effects. As oxygen significantly affects cell function, we established a dual perfluorocarbon method that utilizes (19)F nuclear magnetic resonance spectroscopy, with perfluorocarbons as oxygen concentration markers, to noninvasively monitor dissolved oxygen concentration (DO) in βTC-tet cell-containing alginate beads and at the implantation milieu. Beads were implanted in the peritoneal cavity of normal and streptozotocin-induced diabetic mice. Using this method, the feasibility of acquiring real-time in vivo DO measurements was demonstrated. Results showed that the mouse peritoneal environment is hypoxic and the DO is further reduced when βTC-tet cell constructs were implanted. The DO within cell-containing beads decreased considerably over time and could be correlated with the relative changes in the number of viable encapsulated cells. The reduction of construct DO due to the metabolic activity of the βTC-tet cells was also compatible with the implant therapeutic function, as observed in the reversal of hyperglycemia in diabetic mice. The importance of these findings in assessing implant functionality and host animal physiology is discussed.
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Affiliation(s)
- Fernie Goh
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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11
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de Vos P, Spasojevic M, Faas MM. Treatment of diabetes with encapsulated islets. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 670:38-53. [PMID: 20384217 DOI: 10.1007/978-1-4419-5786-3_5] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Cell encapsulation has been proposed for the treatment of a wide variety of diseases since it allows for transplantation of cells in the absence of undesired immunosuppression. The technology has been proposed to be a solution for the treatment of diabetes since it potentially allows a mandatory minute-to-minute regulation of glucose levels without side-effects. Encapsulation is based on the principle that transplanted tissue is protected for the host immune system by a semipermeable capsule. Many different concepts of capsules have been tested. During the past two decades three major approaches of encapsulation have been studied. These include (i) intravascular macrocapsules, which are anastomosed to the vascular system as AV shunt, (ii) extravascular macrocapsules, which are mostly diffusion chambers transplanted at different sites and (iii) extravascular microcapsules transplanted in the peritoneal cavity. The advantages and pitfalls of the three approaches are discussed and compared in view of applicability in clinical islet transplantation.
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Affiliation(s)
- Paul de Vos
- Department of Pathology and Laboratory Medicine, Section of Immunoendocrinology, University of Groningen. Hanzeplein 1, 9700 RB Groningen, The Netherlands.
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Mendelsohn A, Desai T. Inorganic nanoporous membranes for immunoisolated cell-based drug delivery. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 670:104-25. [PMID: 20384222 DOI: 10.1007/978-1-4419-5786-3_10] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Materials advances enabled by nanotecbnology have brought about promising approaches to improve the encapsulation mechanism for immunoisolated cell-based drug delivery. Cell-based drug delivery is a promising treatment for many diseases but has thus far achieved only limited clinical success. Treatment of insulin dependent diabetes mellitus (IDDM) by transplantation of pancreatic beta-cells represents the most anticipated application ofcell-based drug delivery technology. This review outlines the challenges involved with maintaining transplanted cell viability and discusses how inorganic nanoporous membranes may be useful in achieving clinical success.
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Affiliation(s)
- Adam Mendelsohn
- UCSF/UCB Joint Graduate Group in Bioengineering, University of California, San Francisco, University of California, Berkeley, USA
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13
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Abalovich AG, Bacqué MC, Grana D, Milei J. Pig pancreatic islet transplantation into spontaneously diabetic dogs. Transplant Proc 2009; 41:328-30. [PMID: 19249548 DOI: 10.1016/j.transproceed.2008.08.159] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2008] [Accepted: 08/14/2008] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Pig islet xenotransplantation represents an attractive way to solve our human organ shortage. In this preclinical protocol, we implanted adult porcine islets microencapsulated in alginate-polylysin into insulin-dependent diabetic dogs. METHODS Pancreata were obtained from animals weighing 100 to 150 kg in a slaughterhouse. The islets were isolated by collagenase digestion. The encapsulation technique was a modification of Sun's method. Isolated islets (5000 islet equivalents per kilogram of dog weight) were mixed with 1.6% low-viscocity alginate. Microcapsules were cultured for 36 hours before implantation. The five dogs were in healthy prior to induction of diabetes mellitus at least 1 year prior. Under sedation, we implanted microcapsules. We performed determinations of peripheral blood insulin at baseline and every 3 months as well as glycosylated hemoglobin at baseline and every 4 months. During follow-up, glycemia was estimated twice a day at 3 hours after morning and night meals using a blood glucose monitoring system. RESULTS We observed significant decrease (20%-80%) in insulin needs (P < .01). Of note, before the procedure no hormone was detected in the blood at 6 to 12 months after transplantation, plasma insulin had improved significantly (P < .05) and glycosylated hemoglobin also showed a significant decrease (P < .01). All owners subjectively claimed that their animals were enjoying a better quality of life. DISCUSSION Our preliminary data suggested that pig islet microencapsulation achieved metabolic control in type I diabetic dogs without the risk of immunosuppression using one or two procedures per year.
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Affiliation(s)
- A G Abalovich
- Universidad de San Martín, Escuela de Ciencia y Tecnología, Buenos Aires, Argentina.
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Battiston B, Raimondo S, Tos P, Gaidano V, Audisio C, Scevola A, Perroteau I, Geuna S. Chapter 11 Tissue Engineering of Peripheral Nerves. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2009; 87:227-49. [DOI: 10.1016/s0074-7742(09)87011-6] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Yang KC, Wu CC, Lin FH, Qi Z, Kuo TF, Cheng YH, Chen MP, Sumi S. Chitosan/gelatin hydrogel as immunoisolative matrix for injectable bioartificial pancreas. Xenotransplantation 2008; 15:407-16. [DOI: 10.1111/j.1399-3089.2008.00503.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Wilson JT, Chaikof EL. Challenges and emerging technologies in the immunoisolation of cells and tissues. Adv Drug Deliv Rev 2008; 60:124-45. [PMID: 18022728 DOI: 10.1016/j.addr.2007.08.034] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Accepted: 08/13/2007] [Indexed: 12/22/2022]
Abstract
Protection of transplanted cells from the host immune system using immunoisolation technology will be important in realizing the full potential of cell-based therapeutics. Microencapsulation of cells and cell aggregates has been the most widely explored immunoisolation strategy, but widespread clinical application of this technology has been limited, in part, by inadequate transport of nutrients, deleterious innate inflammatory responses, and immune recognition of encapsulated cells via indirect antigen presentation pathways. To reduce mass transport limitations and decrease void volume, recent efforts have focused on developing conformal coatings of micron and submicron scale on individual cells or cell aggregates. Additionally, anti-inflammatory and immunomodulatory capabilities are being integrated into immunoisolation devices to generate bioactive barriers that locally modulate host responses to encapsulated cells. Continued exploration of emerging paradigms governed by the inherent challenges associated with immunoisolation will be critical to actualizing the clinical potential of cell-based therapeutics.
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Calafiore R, Basta G. Artificial pancreas to treat type 1 diabetes mellitus. METHODS IN MOLECULAR MEDICINE 2007; 140:197-236. [PMID: 18085211 DOI: 10.1007/978-1-59745-443-8_12] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Substitution of diseased organ/tissues with totally artificial machines or transplantable biohybrid devices where functionally competent cells are enveloped within immunoprotective artificial membranes could represent one of the future goals in medicine. In particular, artificial or, closer to feasibility, biohybrid artificial pancreas (BHAP) could replace the function of pancreatic islet beta-cells that have been destroyed by autoimmunity, thereby obviating the need to treat patients with type 1 diabetes mellitus (TIDM) with multiple daily insulin injections. State-of-the-art diabetes therapy and perspectives in the use of BHAP, with special regard to islet-cell-containing microcapsules fabricated with alginate-based polymers, including applications to experimental animal models according to different chemical procedures, are reviewed. Special emphasis has been given to preparation methods, immunoprotection strategies, and biocompatibility of the islet-cell-containing microbarriers, as well as to approaches to ameliorate these features. Currently available BHAP prototypes have been critically reviewed to define expectations about the next generation devices targeting the final cure of TIDM.
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18
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Black SP, Constantinidis I, Cui H, Tucker-Burden C, Weber CJ, Safley SA. Immune responses to an encapsulated allogeneic islet β-cell line in diabetic NOD mice. Biochem Biophys Res Commun 2006; 340:236-43. [PMID: 16375863 DOI: 10.1016/j.bbrc.2005.11.180] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2005] [Accepted: 11/22/2005] [Indexed: 02/02/2023]
Abstract
Our goal is to develop effective islet grafts for treating type 1 diabetes. Since human islets are scarce, we evaluated the efficacy of a microencapsulated insulin-secreting conditionally transformed allogeneic beta-cell line (betaTC-tet) in non-obese diabetic mice treated with tetracycline to inhibit cell growth. Relatively low serum levels of tetracycline controlled proliferation of betaTC-tet cells without inhibiting effective control of hyperglycemia in recipients. There was no significant host cellular reaction to the allografts or host cell adherence to microcapsules, and host cytokine levels were similar to those of sham-operated controls. We conclude that encapsulated allogeneic beta-cell lines may be clinically relevant, because they effectively restore euglycemia and do not elicit a strong cellular immune response following transplantation. To our knowledge, this is the first extensive characterization of the kinetics of host cellular and cytokine responses to an encapsulated islet cell line in an animal model of type 1 diabetes.
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Affiliation(s)
- Sasha P Black
- Charles River Laboratories, Pre-clinical Services Montreal, Senneville, Que., Canada H9X 3R3.
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19
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Safley SA, Kapp LM, Tucker-Burden C, Hering B, Kapp JA, Weber CJ. Inhibition of cellular immune responses to encapsulated porcine islet xenografts by simultaneous blockade of two different costimulatory pathways. Transplantation 2005; 79:409-18. [PMID: 15729166 DOI: 10.1097/01.tp.0000150021.06027.dc] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Transplantation of human islets has been successful clinically. Since human islets are scarce, we are studying microencapsulated porcine islet xenografts in nonobese diabetic (NOD) mice. We have evaluated the cellular immune response in NOD mice with and without dual costimulatory blockade. METHODS Alginate-poly-L-lysine-encapsulated adult porcine islets were transplanted i.p. in untreated diabetic NODs and NODs treated with CTLA4-Ig to block CD28/B7 and with anti-CD154 mAb to inhibit CD40/CD40-ligand interactions. Groups of mice were sacrificed on subsequent days; microcapsules were evaluated by histology; peritoneal cells were analyzed by FACS; and peritoneal cytokines were quantified by ELISA. Controls included immunoincompetent NOD-Scids and diabetic NODs given sham surgery or empty microcapsules. RESULTS Within 20 days, encapsulated porcine islets induced accumulation of large numbers of macrophages, eosinophils, and significant numbers of CD4 and CD8 T cells at the graft site, and all grafts were rejected. During rejection, IFNgamma, IL-12 and IL-5 were significantly elevated over sham-operated controls, whereas IL-2, TNFalpha, IL-4, IL-6, IL-10, IL-1beta and TGFbeta were unchanged. Treatment with CTLA4-Ig and anti-CD154 prevented graft destruction in all animals during the 26 days of the experiment, dramatically inhibited recruitment of host inflammatory cells, and inhibited peritoneal IFNgamma and IL-5 concentrations while delaying IL-12 production. CONCLUSIONS When two different pathways of T cell costimulation were blocked, T cell-dependent inflammatory responses were inhibited, and survival of encapsulated islet xenografts was significantly prolonged. These findings suggest synergy between encapsulation of donor islets and simultaneous blockade of two host costimulatory pathways in prolonging xenoislet transplant survival.
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Affiliation(s)
- Susan A Safley
- Gottlich Laboratory for Diabetes and Islet Transplant Research, Department of Surgery, Emory University School of Medicine, 5105 Woodruff Memorial Building, 101 Woodruff Circle, Atlanta, GA 30322, USA.
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20
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de Groot M, Schuurs TA, van Schilfgaarde R. Causes of limited survival of microencapsulated pancreatic islet grafts. J Surg Res 2004; 121:141-50. [PMID: 15313388 DOI: 10.1016/j.jss.2004.02.018] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2003] [Indexed: 01/02/2023]
Abstract
Successful transplantation of pancreatic tissue has been demonstrated to be an efficacious method of restoring glycemic control in type 1 diabetic patients. To establish graft acceptance patients require lifelong immunosuppression, which in turn is associated with severe deleterious side effects. Microencapsulation is a technique that enables the transplantation of pancreatic islets in the absence of immunosuppression by protecting the islet tissue through a mechanical barrier. This protection may even allow for the transplantation of animal tissue, which opens the perspective of using animal donors as a means to solve the problem of organ shortage. Microencapsulation is not yet applied in clinical practice, mainly because encapsulated islet graft survival is limited. In the present review we discuss the principal causes of microencapsulated islet graft failure, which are related to a lack of biocompatibility, limited immunoprotective properties, and hypoxia. Next to the causes of encapsulated islet graft failure we discuss possible improvements in the encapsulation technique and additional methods that could prolong encapsulated islet graft survival. Strategies that may well support encapsulated islet grafts include co-encapsulation of islets with Sertoli cells, the genetic modification of islet cells, the creation of an artificial implantation site, and the use of alternative donor sources. We conclude that encapsulation in combination with one or more of these additional strategies may well lead to a simple and safe transplantation therapy as a cure for diabetes.
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Affiliation(s)
- Martijn de Groot
- Surgical Research Laboratory, Department of Surgery, University Hospital Groningen, Hanzeplein 1 (CMC V, Y2144), 9713 GZ Groningen, Netherlands.
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21
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Murakami Y, Iwata H, Kitano E, Kitamura H, Ikada Y. Dextran sulfate as a material for the preparation of a membrane for immunoisolation. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2004; 14:875-85. [PMID: 14661867 DOI: 10.1163/156856203322381384] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Bioartificial pancreas, in which the islets of Langerhans (islets) are enclosed in an artificial membrane to be protected from the host immune system, is expected to be a promising medical device to treat patients who suffer from insulin-dependent diabetes. Our strategy for preparation of a bioartificial pancreas involves utilizing a membrane including polymeric materials that can inhibit the complement. In our series of studies, we have examined interactions of various polyanions with the complement system to search for potential complement inhibitors. In this study, we concentrated our efforts to clarify the effects of dextran sulfate on the complement system. All of the dextran sulfates examined inhibited the complement activation through both classical and alternative pathways as previously reported. In addition to their inhibitory effects, a certain species of dextran sulfate (molecular mass 10 kDa, degree of sulfonation in a pyranose ring 1.99) specifically degraded C3 without complement activation and, thus, anaphylatoxins that trigger inflammatory reactions were not generated. These facts suggest that a membrane including dextran sulfate effectively protects the islet cells from humoral immunity in addition to not triggering inflammatory reactions. These properties of the membrane make it suitable for a bioratificial pancreas.
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Affiliation(s)
- Yoshinobu Murakami
- Institute for Frontier Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
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22
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Yanay O, Barry SC, Flint LY, Brzezinski M, Barton RW, Osborne WRA. Long-Term Erythropoietin Gene Expression from Transduced Cells in Bioisolator Devices. Hum Gene Ther 2003; 14:1587-93. [PMID: 14633401 DOI: 10.1089/104303403322542239] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Recombinant erythropoietin (EPO) is widely administered for long-term treatment of anemia associated with renal failure and other chronic diseases. The ability to deliver EPO by gene therapy would have clinical and economic benefit. We compared autologous and allogeneic transduced primary vascular smooth muscle cells for their ability to provide sustained EPO gene expression when encapsulated in TheraCyte devices implanted subcutaneously (SQ) or intraperitoneally (IP) in rats. Cells were transduced with retrovirus vector LrEpSN encoding rat EPO cDNA. Rats that received either autologous or allogeneic transduced cells showed elevated hematocrits (HCTs) ranging from 50 to 79% that were sustained for more than 12 months. The HCT of control rats remained at baseline (45.8%). Rats that received second SQ implants of either autologous or allogeneic cells showed elevations in hematocrit that were sustained for up to 12 months, suggesting the absence of immunological responses to transduced cells or implant material. All experimental groups had statistically significant elevated HCT (p < 0.001) when compared with controls. Both SQ and IP implantation were equally effective in delivering EPO long term. There were no significant differences in white blood cell (WBC) or platelet (PLT) values between treated and control animals. Implantation of TheraCyte devices was well tolerated and histological evaluation of the devices up to 12 months after surgery revealed a high degree of vascularization and no evidence of host immune response. TheraCyte devices offer a simple and safe gene delivery system that provides sustained therapeutic gene expression, permit removal and implantation of new devices, and do not require immunosuppression of the host.
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MESH Headings
- Anemia/therapy
- Animals
- Blood Platelets/metabolism
- Cells, Cultured
- DNA, Complementary/metabolism
- Erythropoietin/biosynthesis
- Erythropoietin/genetics
- Gene Expression
- Genetic Therapy/methods
- Genetic Vectors
- Hematocrit
- Leukocytes/metabolism
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- Rats
- Rats, Inbred F344
- Rats, Wistar
- Retroviridae/genetics
- Time Factors
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Affiliation(s)
- Ofer Yanay
- Department of Pediatrics, University of Washington, Seattle, WA 98195, USA
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Safley SA, Kapp JA, Weber CJ. Proliferative and cytokine responses in CTLA4-Ig-treated diabetic NOD mice transplanted with microencapsulated neonatal porcine ICCs. Cell Transplant 2003; 11:695-705. [PMID: 12518896 DOI: 10.3727/000000002783985413] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Our goal is to develop effective islet xenografts for treating human diabetes. We have studied microencapsulated neonatal porcine islet cell clusters (ICCs) transplanted intraperitoneally in spontaneously diabetic NOD mice, where they function to maintain normoglycemia in the autoimmune host. Nonencapsulated neonatal porcine ICCs functioned for 4.5 +/- 0.5 days before being rejected; encapsulation prolonged graft function to 17 +/- 2 days. CTLA4-Ig treatment did not enhance the survival of nonencapsulated ICCs. However, CTLA4-Ig treatment significantly extended the function of encapsulated ICCs to 73 +/- 5 days. Histological analyses demonstrated a profuse pericapsular cellular reaction associated with rejection of encapsulated islet xenografts in untreated mice, while this reaction was significantly reduced in CTLA4-Ig-treated mice. To study mechanisms of xenograft rejection in this model, we analyzed proliferative responses to neonatal porcine ICCs and cytokines present in the peritoneal cavities of transplanted mice. Spleen cells from both CTLA4-Ig-treated and untreated rejecting NODs exhibited vigorous proliferation in the absence of antigenic stimulation, suggesting prior activation in vivo, while splenocytes from CTLA4-Ig-treated NODs with functioning grafts had low proliferative levels, equal to controls. Islet-specific proliferation was not detected in islet-rejecting mice, perhaps due to their high background levels. With the exception of elevated IL-6 levels, empty capsules did not provoke a significant peritoneal cytokine response compared with sham surgery or untransplanted control mice. However, IL-5, IL-12, TGF-beta, and IL-1beta were significantly elevated in NODs receiving encapsulated neonatal porcine ICCs compared with untransplanted controls. There were no significant differences between peritoneal cytokine concentrations in CTLA4-Ig-treated mice with long-term functioning grafts compared to mice that rejected grafts at earlier time points. We conclude that the combination of donor islet microencapsulation and brief treatment of the recipient with co-stimulatory blockade delays sensitization of the host, possibly by altering mechanism(s) for recruitment and/or activation of host effector cells.
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Affiliation(s)
- Susan A Safley
- Department of Surgery, Emory University School of Medicine, Atlanta, GA 30322, USA.
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24
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Zhang Z, Bédard E, Luo Y, Wang H, Deng S, Kelvin D, Zhong R. Animal models in xenotransplantation. Expert Opin Investig Drugs 2000; 9:2051-68. [PMID: 11060792 DOI: 10.1517/13543784.9.9.2051] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The severe shortage of donor organs has provided a strong impetus to push the investigation into the use of animal organs for humans. Xenotransplantation will not only benefit patients, but also represents a unique and potentially profitable business opportunity. However, there are many barriers to successful clinical xenotransplantation, including immunological barriers, physiological incompatibility, zoonosis and ethical concerns. This overview will focus on currently available animal models used in attempts to break through the immunological barriers to xenotransplantation. There are many advantages to using small animal, namely rodent, models in xenotransplantation research. For example, the use of the mouse model allows the use of knockout mice and careful dissection of rejection mechanisms at the molecular level. The following models can be used to study hyperacute rejection (HAR): guinea-pig-to-rat, mouse-to-rabbit, guinea-pig-to-mouse, rat-to-presensitised mouse and rat-to-alpha-Gal knockout mouse. The hamster-to-rat, mouse-to-rat and rat-to-mouse models are commonly used to study acute vascular rejection. Large animal models are complex and expensive, but they are more relevant to clinical xenotransplantation. Based on experiments using transgenic pig-to-primate models, HAR can be overcome. However, acute vascular rejection remains a major barrier at the present time. A pig cartilage-to-monkey model has been developed to study chronic rejection. Other novel models such as pig venous segment-to-monkey model and rat-to-primate model may represent viable options to study immunological barriers following xenotransplantation. Like many other medical breakthroughs, animal research will continue to make enormous contributions towards the eventual success of xenotransplantation.
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Affiliation(s)
- Z Zhang
- London Health Sciences Center, University Campus, 339 Windermere Road, London, Ontario, N6A 5A5, Canada.
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