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Einstein SA, Steyn LV, Weegman BP, Suszynski TM, Sambanis A, O'Brien TD, Avgoustiniatos ES, Firpo MT, Graham ML, Janecek J, Eberly LE, Garwood M, Putnam CW, Papas KK. Hypoxia within subcutaneously implanted macroencapsulation devices limits the viability and functionality of densely loaded islets. FRONTIERS IN TRANSPLANTATION 2023; 2:1257029. [PMID: 38993891 PMCID: PMC11235299 DOI: 10.3389/frtra.2023.1257029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 10/20/2023] [Indexed: 07/13/2024]
Abstract
Introduction Subcutaneous macroencapsulation devices circumvent disadvantages of intraportal islet therapy. However, a curative dose of islets within reasonably sized devices requires dense cell packing. We measured internal PO2 of implanted devices, mathematically modeled oxygen availability within devices and tested the predictions with implanted devices containing densely packed human islets. Methods Partial pressure of oxygen (PO2) within implanted empty devices was measured by noninvasive 19F-MRS. A mathematical model was constructed, predicting internal PO2, viability and functionality of densely packed islets as a function of external PO2. Finally, viability was measured by oxygen consumption rate (OCR) in day 7 explants loaded at various islet densities. Results In empty devices, PO2 was 12 mmHg or lower, despite successful external vascularization. Devices loaded with human islets implanted for 7 days, then explanted and assessed by OCR confirmed trends proffered by the model but viability was substantially lower than predicted. Co-localization of insulin and caspase-3 immunostaining suggested that apoptosis contributed to loss of beta cells. Discussion Measured PO2 within empty devices declined during the first few days post-transplant then modestly increased with neovascularization around the device. Viability of islets is inversely related to islet density within devices.
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Affiliation(s)
- Samuel A Einstein
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN, United States
- Department of Radiology, The Pennsylvania State University, Hershey, PA, United States
| | - Leah V Steyn
- Department of Surgery, University of Arizona, Tucson, AZ, United States
| | - Bradley P Weegman
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN, United States
- Sylvatica Biotech Inc., North Charleston, SC, United States
| | - Thomas M Suszynski
- Department of Plastic Surgery, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Athanassios Sambanis
- Department of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Timothy D O'Brien
- Veterinary Population Medicine Department, University of Minnesota, Saint Paul, MN, United States
- Department of Medicine, Stem Cell Institute, University of Minnesota, Minneapolis, MN, United States
| | | | - Meri T Firpo
- Department of Medicine, Stem Cell Institute, University of Minnesota, Minneapolis, MN, United States
| | - Melanie L Graham
- Veterinary Population Medicine Department, University of Minnesota, Saint Paul, MN, United States
- Department of Surgery, Preclinical Research Center, University of Minnesota, Saint Paul, MN, United States
| | - Jody Janecek
- Department of Surgery, Preclinical Research Center, University of Minnesota, Saint Paul, MN, United States
| | - Lynn E Eberly
- Division of Biostatistics, University of Minnesota, Minneapolis, MN, United States
| | - Michael Garwood
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN, United States
| | - Charles W Putnam
- Department of Surgery, University of Arizona, Tucson, AZ, United States
| | - Klearchos K Papas
- Department of Surgery, University of Arizona, Tucson, AZ, United States
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2
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Wang Y, Wang K, Luo Y, Chen H. Hydrogel-Bondable Asymmetric Planar Membranes with Hierarchical Pore Structures for Cell Scaffolding and Encapsulation. ACS Biomater Sci Eng 2023; 9:1706-1719. [PMID: 36795620 DOI: 10.1021/acsbiomaterials.2c01415] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Biomaterials for cell replacement therapy could facilitate the delivery, function, and retrieval of transplanted therapeutic cells. However, the limited capacity to accommodate a sufficient quantity of cells in biomedical devices has hindered the success of clinical application, resulting from the suboptimal spatial organization of cells and insufficient permeation of nutrients in the materials. Herein, through the immersion-precipitation phase transfer (IPPT) process from polyether sulfone (PES), we develop planar asymmetric membranes with a hierarchical pore architecture spanning from nanopores (∼20 nm) in the dense skin and open-ended microchannel arrays with gradient pore size increasing vertically from microns to ∼100 μm. The nanoporous skin would be an ultrathin diffusion barrier, while the microchannels could support high-density cell loading by acting as separate chambers allowing uniform distribution of cells in the scaffold. Alginate hydrogel could permeate into the channels and form a sealing layer after gelation, which could slow down the invasion of host immune cells into the scaffold. The hybrid thin-sheet encapsulation system (∼400 μm thick) could protect allogeneic cells over half-year after intraperitoneal (IP) implantation in immune-competent mice. Such structural membranes and plastic-hydrogel hybrids of thin dimensions could find important applications in cell delivery therapy.
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Affiliation(s)
- Yi Wang
- Department of Biomedical Engineering, College of Future Technology, Peking University, Haidian District, Beijing 100871, China
| | - Kai Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University; Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing 100191, China
| | - Ying Luo
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Haifeng Chen
- Department of Biomedical Engineering, College of Future Technology, Peking University, Haidian District, Beijing 100871, China
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3
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Duy Nguyen BT, Nguyen Thi HY, Nguyen Thi BP, Kang DK, Kim JF. The Roles of Membrane Technology in Artificial Organs: Current Challenges and Perspectives. MEMBRANES 2021; 11:239. [PMID: 33800659 PMCID: PMC8065507 DOI: 10.3390/membranes11040239] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 03/20/2021] [Accepted: 03/20/2021] [Indexed: 02/07/2023]
Abstract
The recent outbreak of the COVID-19 pandemic in 2020 reasserted the necessity of artificial lung membrane technology to treat patients with acute lung failure. In addition, the aging world population inevitably leads to higher demand for better artificial organ (AO) devices. Membrane technology is the central component in many of the AO devices including lung, kidney, liver and pancreas. Although AO technology has improved significantly in the past few decades, the quality of life of organ failure patients is still poor and the technology must be improved further. Most of the current AO literature focuses on the treatment and the clinical use of AO, while the research on the membrane development aspect of AO is relatively scarce. One of the speculated reasons is the wide interdisciplinary spectrum of AO technology, ranging from biotechnology to polymer chemistry and process engineering. In this review, in order to facilitate the membrane aspects of the AO research, the roles of membrane technology in the AO devices, along with the current challenges, are summarized. This review shows that there is a clear need for better membranes in terms of biocompatibility, permselectivity, module design, and process configuration.
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Affiliation(s)
- Bao Tran Duy Nguyen
- Department of Energy and Chemical Engineering, Incheon National University, Incheon 22012, Korea; (B.T.D.N.); (H.Y.N.T.); (B.P.N.T.)
| | - Hai Yen Nguyen Thi
- Department of Energy and Chemical Engineering, Incheon National University, Incheon 22012, Korea; (B.T.D.N.); (H.Y.N.T.); (B.P.N.T.)
| | - Bich Phuong Nguyen Thi
- Department of Energy and Chemical Engineering, Incheon National University, Incheon 22012, Korea; (B.T.D.N.); (H.Y.N.T.); (B.P.N.T.)
| | - Dong-Ku Kang
- Department of Chemistry, Incheon National University, Incheon 22012, Korea
| | - Jeong F. Kim
- Department of Energy and Chemical Engineering, Incheon National University, Incheon 22012, Korea; (B.T.D.N.); (H.Y.N.T.); (B.P.N.T.)
- Innovation Center for Chemical Engineering, Incheon National University, Incheon 22012, Korea
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4
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Ernst AU, Bowers DT, Wang LH, Shariati K, Plesser MD, Brown NK, Mehrabyan T, Ma M. Nanotechnology in cell replacement therapies for type 1 diabetes. Adv Drug Deliv Rev 2019; 139:116-138. [PMID: 30716349 PMCID: PMC6677642 DOI: 10.1016/j.addr.2019.01.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Revised: 01/17/2019] [Accepted: 01/28/2019] [Indexed: 12/12/2022]
Abstract
Islet transplantation is a promising long-term, compliance-free, complication-preventing treatment for type 1 diabetes. However, islet transplantation is currently limited to a narrow set of patients due to the shortage of donor islets and side effects from immunosuppression. Encapsulating cells in an immunoisolating membrane can allow for their transplantation without the need for immunosuppression. Alternatively, "open" systems may improve islet health and function by allowing vascular ingrowth at clinically attractive sites. Many processes that enable graft success in both approaches occur at the nanoscale level-in this review we thus consider nanotechnology in cell replacement therapies for type 1 diabetes. A variety of biomaterial-based strategies at the nanometer range have emerged to promote immune-isolation or modulation, proangiogenic, or insulinotropic effects. Additionally, coating islets with nano-thin polymer films has burgeoned as an islet protection modality. Materials approaches that utilize nanoscale features manipulate biology at the molecular scale, offering unique solutions to the enduring challenges of islet transplantation.
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Affiliation(s)
- Alexander U Ernst
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Daniel T Bowers
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Long-Hai Wang
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Kaavian Shariati
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Mitchell D Plesser
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Natalie K Brown
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Tigran Mehrabyan
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Minglin Ma
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA.
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Salg GA, Giese NA, Schenk M, Hüttner FJ, Felix K, Probst P, Diener MK, Hackert T, Kenngott HG. The emerging field of pancreatic tissue engineering: A systematic review and evidence map of scaffold materials and scaffolding techniques for insulin-secreting cells. J Tissue Eng 2019; 10:2041731419884708. [PMID: 31700597 PMCID: PMC6823987 DOI: 10.1177/2041731419884708] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 10/04/2019] [Indexed: 12/18/2022] Open
Abstract
A bioartificial endocrine pancreas is proposed as a future alternative to current treatment options. Patients with insulin-secretion deficiency might benefit. This is the first systematic review that provides an overview of scaffold materials and techniques for insulin-secreting cells or cells to be differentiated into insulin-secreting cells. An electronic literature survey was conducted in PubMed/MEDLINE and Web of Science, limited to the past 10 years. A total of 197 articles investigating 60 different materials met the inclusion criteria. The extracted data on materials, cell types, study design, and transplantation sites were plotted into two evidence gap maps. Integral parts of the tissue engineering network such as fabrication technique, extracellular matrix, vascularization, immunoprotection, suitable transplantation sites, and the use of stem cells are highlighted. This systematic review provides an evidence-based structure for future studies. Accumulating evidence shows that scaffold-based tissue engineering can enhance the viability and function or differentiation of insulin-secreting cells both in vitro and in vivo.
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Affiliation(s)
- Gabriel Alexander Salg
- Department of General, Abdominal and Transplantation Surgery, Heidelberg University Hospital, Heidelberg, Germany
| | - Nathalia A Giese
- Department of General, Abdominal and Transplantation Surgery, Heidelberg University Hospital, Heidelberg, Germany
| | - Miriam Schenk
- Department of General, Abdominal and Transplantation Surgery, Heidelberg University Hospital, Heidelberg, Germany
| | - Felix J Hüttner
- Department of General, Abdominal and Transplantation Surgery, Heidelberg University Hospital, Heidelberg, Germany
| | - Klaus Felix
- Department of General, Abdominal and Transplantation Surgery, Heidelberg University Hospital, Heidelberg, Germany
| | - Pascal Probst
- Department of General, Abdominal and Transplantation Surgery, Heidelberg University Hospital, Heidelberg, Germany
| | - Markus K Diener
- Department of General, Abdominal and Transplantation Surgery, Heidelberg University Hospital, Heidelberg, Germany
| | - Thilo Hackert
- Department of General, Abdominal and Transplantation Surgery, Heidelberg University Hospital, Heidelberg, Germany
| | - Hannes Götz Kenngott
- Department of General, Abdominal and Transplantation Surgery, Heidelberg University Hospital, Heidelberg, Germany
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Groot Nibbelink M, Skrzypek K, Karbaat L, Both S, Plass J, Klomphaar B, van Lente J, Henke S, Karperien M, Stamatialis D, van Apeldoorn A. An important step towards a prevascularized islet microencapsulation device: in vivo prevascularization by combination of mesenchymal stem cells on micropatterned membranes. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2018; 29:174. [PMID: 30413974 PMCID: PMC6244873 DOI: 10.1007/s10856-018-6178-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 10/17/2018] [Indexed: 06/08/2023]
Abstract
Extrahepatic transplantation of islets of Langerhans could aid in better survival of islets after transplantation. When islets are transfused into the liver 60-70% of them are lost immediately after transplantation. An important factor for a successful extrahepatic transplantation is a well-vascularized tissue surrounding the implant. There are many strategies known for enhancing vessel formation such as adding cells with endothelial potential, the combination with angiogenic factors and / or applying surface topography at the exposed surface of the device. Previously we developed porous, micropatterned membranes which can be applied as a lid for an islet encapsulation device and we showed that the surface topography induces human umbilical vein endothelial cell (HUVEC) alignment and interconnection. This was achieved without the addition of hydrogels, often used in angiogenesis assays. In this work, we went one step further towards clinical implementation of the device by combining this micropatterned lid with Mesenchymal Stem Cells (MSCs) to facilitate prevascularization in vivo. As for HUVECs, the micropatterned membranes induced MSC alignment and organization in vitro, an important contributor to vessel formation, whereas in vivo (subcutaneous rat model) they contributed to improved implant prevascularization. In fact, the combination of MSCs seeded on the micropatterned membrane induced the highest vessel formation score in 80% of the sections.
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Affiliation(s)
- Milou Groot Nibbelink
- Developmental BioEngineering, MIRA Institute of Biomedical Technology and Technical Medicine, University of Twente, Maastricht, The Netherlands.
| | - Katarzyna Skrzypek
- (Bio)artificial organs. Department of Biomaterials Science and Technology, MIRA Institute of Biomedical Technology and Technical Medicine University of Twente, Maastricht, The Netherlands
| | - Lisanne Karbaat
- (Bio)artificial organs. Department of Biomaterials Science and Technology, MIRA Institute of Biomedical Technology and Technical Medicine University of Twente, Maastricht, The Netherlands
| | - Sanne Both
- Developmental BioEngineering, MIRA Institute of Biomedical Technology and Technical Medicine, University of Twente, Maastricht, The Netherlands
| | - Jacqueline Plass
- Developmental BioEngineering, MIRA Institute of Biomedical Technology and Technical Medicine, University of Twente, Maastricht, The Netherlands
| | - Bettie Klomphaar
- Biomedical Signals and Systems, MIRA Institute of Biomedical Technology and Technical Medicine, University of Twente, Maastricht, The Netherlands
| | - Jéré van Lente
- Developmental BioEngineering, MIRA Institute of Biomedical Technology and Technical Medicine, University of Twente, Maastricht, The Netherlands
| | - Sieger Henke
- Developmental BioEngineering, MIRA Institute of Biomedical Technology and Technical Medicine, University of Twente, Maastricht, The Netherlands
| | - Marcel Karperien
- Developmental BioEngineering, MIRA Institute of Biomedical Technology and Technical Medicine, University of Twente, Maastricht, The Netherlands
| | - Dimitrios Stamatialis
- (Bio)artificial organs. Department of Biomaterials Science and Technology, MIRA Institute of Biomedical Technology and Technical Medicine University of Twente, Maastricht, The Netherlands
| | - Aart van Apeldoorn
- Developmental BioEngineering, MIRA Institute of Biomedical Technology and Technical Medicine, University of Twente, Maastricht, The Netherlands
- Complex Tissue Regeneration, MERLN Institute for Technology Inspired Regenerative Medicine, Maastricht University, Maastricht, The Netherlands
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7
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Abstract
Review of emerging advances and persisting challenges in the engineering and translation of islet encapsulation technologies.
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Affiliation(s)
| | - Long-Hai Wang
- Department of Biological and Environmental Engineering
- Cornell University
- Ithaca
- USA
| | - Minglin Ma
- Department of Biological and Environmental Engineering
- Cornell University
- Ithaca
- USA
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8
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Liu Z, Hu W, He T, Dai Y, Hara H, Bottino R, Cooper DKC, Cai Z, Mou L. Pig-to-Primate Islet Xenotransplantation: Past, Present, and Future. Cell Transplant 2017; 26:925-947. [PMID: 28155815 PMCID: PMC5657750 DOI: 10.3727/096368917x694859] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 03/21/2017] [Indexed: 12/17/2022] Open
Abstract
Islet allotransplantation results in increasing success in treating type 1 diabetes, but the shortage of deceased human donor pancreata limits progress. Islet xenotransplantation, using pigs as a source of islets, is a promising approach to overcome this limitation. The greatest obstacle is the primate immune/inflammatory response to the porcine (pig) islets, which may take the form of rapid early graft rejection (the instant blood-mediated inflammatory reaction) or T-cell-mediated rejection. These problems are being resolved by the genetic engineering of the source pigs combined with improved immunosuppressive therapy. The results of pig-to-diabetic nonhuman primate islet xenotransplantation are steadily improving, with insulin independence being achieved for periods >1 year. An alternative approach is to isolate islets within a micro- or macroencapsulation device aimed at protecting them from the human recipient's immune response. Clinical trials using this approach are currently underway. This review focuses on the major aspects of pig-to-primate islet xenotransplantation and its potential for treatment of type 1 diabetes.
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Affiliation(s)
- Zhengzhao Liu
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center, Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen, Guangdong, P.R. China
| | - Wenbao Hu
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center, Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen, Guangdong, P.R. China
| | - Tian He
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center, Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen, Guangdong, P.R. China
| | - Yifan Dai
- Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Nanjing, Jiangsu, P.R. China
| | - Hidetaka Hara
- Xenotransplantation Program/Department of Surgery, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Rita Bottino
- Institute for Cellular Therapeutics, Allegheny-Singer Research Institute, Pittsburgh, PA, USA
| | - David K. C. Cooper
- Xenotransplantation Program/Department of Surgery, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Zhiming Cai
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center, Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen, Guangdong, P.R. China
| | - Lisha Mou
- Shenzhen Xenotransplantation Medical Engineering Research and Development Center, Institute of Translational Medicine, Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Shenzhen, Guangdong, P.R. China
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9
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Zhu HT, Lu L, Liu XY, Yu L, Lyu Y, Wang B. Treatment of diabetes with encapsulated pig islets: an update on current developments. J Zhejiang Univ Sci B 2016; 16:329-43. [PMID: 25990050 DOI: 10.1631/jzus.b1400310] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The potential use of allogeneic islet transplantation in curing type 1 diabetes mellitus has been adequately demonstrated, but its large-scale application is limited by the short supply of donor islets and the need for sustained and heavy immunosuppressive therapy. Encapsulation of pig islets was therefore suggested with a view to providing a possible alternative source of islet grafts and avoiding chronic immunosuppression and associated adverse or toxic effects. Nevertheless, several vital elements should be taken into account before this therapy becomes a clinical reality, including cell sources, encapsulation approaches, and implantation sites. This paper provides a comprehensive review of xenotransplantation of encapsulated pig islets for the treatment of type 1 diabetes mellitus, including current research findings and suggestions for future studies.
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Affiliation(s)
- Hai-tao Zhu
- Heart Center, Northwest Women's and Children's Hospital, Xi'an 710061, China; Department of Hepatobiliary Surgery, the First Affiliated Hospital, Medical College, Xi'an Jiaotong University, Xi'an 710061, China; Department of Hand Surgery, China-Japan Union Hospital, Norman Bethune Health Science Center, Jilin University, Changchun 130033, China; Institute of Advanced Surgical Technology and Engineering, Xi'an Jiaotong University, Xi'an 710061, China
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10
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Zhang L, Zhao X, Liu D, Wang H, He C. Polyvinylpyrrolidone-polydimethylsiloxane amphiphilic co-networks: Synthesis, characterization, and perm-selective behavior. J Appl Polym Sci 2016. [DOI: 10.1002/app.42985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Li Zhang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials; College of Materials Science and Engineering, Donghua University; 2999 North Renmin Road, Songjiang District Shanghai 201620 People's Republic of China
| | - Xinzhen Zhao
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials; College of Materials Science and Engineering, Donghua University; 2999 North Renmin Road, Songjiang District Shanghai 201620 People's Republic of China
| | - Dapeng Liu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials; College of Materials Science and Engineering, Donghua University; 2999 North Renmin Road, Songjiang District Shanghai 201620 People's Republic of China
| | - Haiye Wang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials; College of Materials Science and Engineering, Donghua University; 2999 North Renmin Road, Songjiang District Shanghai 201620 People's Republic of China
| | - Chunju He
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials; College of Materials Science and Engineering, Donghua University; 2999 North Renmin Road, Songjiang District Shanghai 201620 People's Republic of China
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11
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Plenderleith RA, Pateman CJ, Rodenburg C, Haycock JW, Claeyssens F, Sammon C, Rimmer S. Arginine-glycine-aspartic acid functional branched semi-interpenetrating hydrogels. SOFT MATTER 2015; 11:7567-7578. [PMID: 26280624 DOI: 10.1039/c5sm00695c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
For the first time a series of functional hydrogels based on semi-interpenetrating networks with both branched and crosslinked polymer components have been prepared and we show the successful use of these materials as substrates for cell culture. The materials consist of highly branched poly(N-isopropyl acrylamide)s with peptide functionalised end groups in a continuous phase of crosslinked poly(vinyl pyrrolidone). Functionalisation of the end groups of the branched polymer component with the GRGDS peptide produces a hydrogel that supports cell adhesion and proliferation. The materials provide a new synthetic functional biomaterial that has many of the features of extracellular matrix, and as such can be used to support tissue regeneration and cell culture. This class of high water content hydrogel material has important advantages over other functional hydrogels in its synthesis and does not require post-processing modifications nor are functional-monomers, which change the polymerisation process, required. Thus, the systems are amenable to large scale and bespoke manufacturing using conventional moulding or additive manufacturing techniques. Processing using additive manufacturing is exemplified by producing tubes using microstereolithography.
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Affiliation(s)
- Richard A Plenderleith
- The Polymer and Biomaterials Chemistry Laboratories, Department of Chemistry, University of Sheffield, Sheffield, South Yorkshire S3 7HF, UK.
| | - Christopher J Pateman
- Department of Materials and Engineering, Kroto Research Institute, University of Sheffield, North Campus, Broad Lane, Sheffield S3 7HQ, UK
| | - Cornelia Rodenburg
- Department of Materials Science and Engineering, University of Sheffield, Mappin Street, Sheffield, S1 3JD, UK
| | - John W Haycock
- Department of Materials and Engineering, Kroto Research Institute, University of Sheffield, North Campus, Broad Lane, Sheffield S3 7HQ, UK
| | - Frederik Claeyssens
- Department of Materials and Engineering, Kroto Research Institute, University of Sheffield, North Campus, Broad Lane, Sheffield S3 7HQ, UK
| | - Chris Sammon
- Materials and Engineering Research Institute, Sheffield Hallam University, Howard Street, Sheffield, South Yorkshire, S1 1WN, UK
| | - Stephen Rimmer
- The Polymer and Biomaterials Chemistry Laboratories, Department of Chemistry, University of Sheffield, Sheffield, South Yorkshire S3 7HF, UK.
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12
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Qiu M, Zhao XZ, Liu DP, He CJ. pH sensitive amphiphilic conetworks based on end-group cross-linking of polydimethylsiloxane pentablock copolymer and polymethylhydrosiloxane. RSC Adv 2015. [DOI: 10.1039/c4ra13866j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A series of pH-responsive amphiphilic conetworks were synthesized through cross-linking of well-defined amphiphilic pentablock copolymers via atom transfer radical polymerization.
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Affiliation(s)
- Ming Qiu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials
- College of Materials Science and Engineering
- Donghua University
- Shanghai
- P. R. China
| | - Xin-Zheng Zhao
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials
- College of Materials Science and Engineering
- Donghua University
- Shanghai
- P. R. China
| | - Da-Peng Liu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials
- College of Materials Science and Engineering
- Donghua University
- Shanghai
- P. R. China
| | - Chun-Ju He
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials
- College of Materials Science and Engineering
- Donghua University
- Shanghai
- P. R. China
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13
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Weegman BP, Suszynski TM, Scott WE, Ferrer J, Avgoustiniatos ES, Anazawa T, O’Brien TD, Rizzari MD, Karatzas T, Jie T, Sutherland DER, Hering BJ, Papas KK. Temperature profiles of different cooling methods in porcine pancreas procurement. Xenotransplantation 2014; 21:574-81. [PMID: 25040217 PMCID: PMC4262706 DOI: 10.1111/xen.12114] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 05/03/2014] [Indexed: 11/30/2022]
Abstract
Porcine islet xenotransplantation is a promising alternative to human islet allotransplantation. Porcine pancreas cooling needs to be optimized to reduce the warm ischemia time (WIT) following donation after cardiac death, which is associated with poorer islet isolation outcomes. This study examines the effect of four different cooling Methods on core porcine pancreas temperature (n = 24) and histopathology (n = 16). All Methods involved surface cooling with crushed ice and chilled irrigation. Method A, which is the standard for porcine pancreas procurement, used only surface cooling. Method B involved an intravascular flush with cold solution through the pancreas arterial system. Method C involved an intraductal infusion with cold solution through the major pancreatic duct, and Method D combined all three cooling Methods. Surface cooling alone (Method A) gradually decreased core pancreas temperature to <10 °C after 30 min. Using an intravascular flush (Method B) improved cooling during the entire duration of procurement, but incorporating an intraductal infusion (Method C) rapidly reduced core temperature 15-20 °C within the first 2 min of cooling. Combining all methods (Method D) was the most effective at rapidly reducing temperature and providing sustained cooling throughout the duration of procurement, although the recorded WIT was not different between Methods (P = 0.36). Histological scores were different between the cooling Methods (P = 0.02) and the worst with Method A. There were differences in histological scores between Methods A and C (P = 0.02) and Methods A and D (P = 0.02), but not between Methods C and D (P = 0.95), which may highlight the importance of early cooling using an intraductal infusion. In conclusion, surface cooling alone cannot rapidly cool large (porcine or human) pancreata. Additional cooling with an intravascular flush and intraductal infusion results in improved core porcine pancreas temperature profiles during procurement and histopathology scores. These data may also have implications on human pancreas procurement as use of an intraductal infusion is not common practice.
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Affiliation(s)
- Brad P. Weegman
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | - Thomas M. Suszynski
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | - William E. Scott
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
- Institute for Cellular Transplantation, Department of Surgery, University of Arizona, Tucson, AZ
| | - Joana Ferrer
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | | | - Takayuki Anazawa
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | | | - Michael D. Rizzari
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | - Theodore Karatzas
- Second Department of Propedeutic Surgery, University of Athens, Athens, Greece
| | - Tun Jie
- Institute for Cellular Transplantation, Department of Surgery, University of Arizona, Tucson, AZ
| | - David ER. Sutherland
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | - Bernhard J. Hering
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
| | - Klearchos K. Papas
- Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN
- Institute for Cellular Transplantation, Department of Surgery, University of Arizona, Tucson, AZ
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14
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Xu J, Qiu M, Ma B, He C. "Near perfect" amphiphilic conetwork based on end-group cross-linking of polydimethylsiloxane triblock copolymer via atom transfer radical polymerization. ACS APPLIED MATERIALS & INTERFACES 2014; 6:15283-15290. [PMID: 25102277 DOI: 10.1021/am5037252] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Novel amphiphilic conetworks (APCNs) with uniform channel size were synthesized through end-cross-linking of well-defined amphiphilic triblock copolymers via atom transfer radical polymerization (ATRP). A new ditelechelic polydimethylsiloxane macroinitiator was synthesized to initiate the polymerization of N,N-dimethylacrylamide. The resulting triblock copolymers show well-defined molecular weight with narrow polydisperisty, which are telechelic modified by allylamine and fully cross-linked with polyhydrosiloxanes through hydrosilylation. Transmission electron microscopy shows that the APCN has the behavior of microphase separation with small channel size and uniform phase domain. The resulting APCNs with idealized microstructure exhibit a combination of excellent properties, i.e., superhigh mechanical strength (4 ± 1 MPa) and elongation ratio (175 ± 25%), outstanding oxygen permeability (350 ± 150 barrers), a high water uptake property, and excellent biocompatibility, indicating that in this way, "near perfect" networks are obtained. These results are better than those reported in the literature, suggesting a promising semipermeable barrier for islet encapsulation in relative biomaterial fields.
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Affiliation(s)
- Jianfeng Xu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University , 2999 North Renmin Road, Songjiang District, Shanghai, 201620, P. R. China
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15
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Vrabelova D, Adin C, Gilor C, Rajab A. Pancreatic islet transplantation: from dogs to humans and back again. Vet Surg 2014; 43:631-41. [PMID: 24909456 DOI: 10.1111/j.1532-950x.2014.12224.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 03/01/2014] [Indexed: 02/06/2023]
Abstract
Pancreatic islet transplantation is a cell-based therapy that provides a potential cure for type 1 diabetes mellitus. After the introduction of an automated method for islet isolation and steroid-free immunosuppressive protocols, reversal of diabetes by islet transplantation is now performed at major human medical centers around the world. Despite extensive use of animal models in islet transplantation research, practical concerns have slowed the introduction of the technique into clinical veterinary practice and only a small number of studies have reported results of transplantation in dogs with spontaneously occurring diabetes mellitus; however, recent advances in islet isolation and encapsulation may make it possible to perform islet transplantation without immunosuppression in companion animals. This review summarizes experimental and clinical studies of pancreatic islet transplantation in dogs, including future directions for cell therapy in animals with naturally occurring disease.
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Affiliation(s)
- Daniela Vrabelova
- Department of Veterinary Clinical Sciences, Ohio State University, Columbus, Ohio
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16
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Colton CK. Oxygen supply to encapsulated therapeutic cells. Adv Drug Deliv Rev 2014; 67-68:93-110. [PMID: 24582600 DOI: 10.1016/j.addr.2014.02.007] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 01/06/2014] [Accepted: 02/19/2014] [Indexed: 02/07/2023]
Abstract
Therapeutic cells encapsulated in immunobarrier devices have promise for treatment of a variety of human diseases without immunosuppression. The absence of sufficient oxygen supply to maintain viability and function of encapsulated tissue has been the most critical impediment to progress. Within the framework of oxygen supply limitations, we review the major issues related to development of these devices, primarily in the context of encapsulated islets of Langerhans for treating diabetes, including device designs and materials, supply of tissue, protection from immune rejection, and maintenance of cell viability and function. We describe various defensive measures investigated to enhance survival of transplanted tissue, and we review the diverse approaches to enhancement of oxygen transport to encapsulated tissue, including manipulation of diffusion distances and oxygen permeability of materials, induction of neovascularization with angiogenic factors and vascularizing membranes, and methods for increasing the oxygen concentration adjacent to encapsulated tissue so as to exceed that in the microvasculature. Recent developments, particularly in this latter area, suggest that the field is ready for clinical trials of encapsulated therapeutic cells to treat diabetes.
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17
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Krishnan L, Touroo J, Reed R, Boland E, Hoying JB, Williams SK. Vascularization and cellular isolation potential of a novel electrospun cell delivery vehicle. J Biomed Mater Res A 2013; 102:2208-19. [PMID: 23913805 DOI: 10.1002/jbm.a.34900] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 07/13/2013] [Accepted: 07/25/2013] [Indexed: 01/11/2023]
Abstract
A clinical need exists for a cell delivery device that supports long-term cell viability, cell retention within the device and retrieval of delivered cells if necessary. Previously, cell isolation devices have been based on hollow fiber membranes, porous polymer scaffolds, alginate systems, or micro-machined membranes. We present the development and characterization of a novel dual porosity electrospun membrane based device, which supports cellular infiltration and vascularization of its outer porous layer and maintains cellular isolation within a lumen bounded by an inner low porosity layer. Electrospinning conditions were initially established to support electrospun fiber deposition onto nonconductive silicone surfaces. With these parameters established, devices for in vivo evaluations were produced using nylon as a nonconductive scaffold for deposition of dual porosity electrospun fibers. The outer porous layer supported the development of a penetrating microcirculation and the membrane supported the transfer of insulin from encapsulated sustained release pellets for 4 weeks. Viable cells implanted within the device could be identified after 2 weeks of implantation. Through the successful demonstration of survival and cellular isolation of human epithelial cells within the implanted devices and the ability to use the device to deliver insulin, we have established the utility of this device toward localized cell transplantation. The cell delivery device establishes a platform to test the feasibility of approaches to cell dose control and cell localization at the site of implantation in the clinical use of modified autologous or allogeneic cells.
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Affiliation(s)
- Laxminarayanan Krishnan
- Cardiovascular Innovation Institute, University of Louisville and Jewish Hospital, Louisville, Kentucky, 40202
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18
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Grundfest-Broniatowski S. What would surgeons like from materials scientists? WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2013; 5:299-319. [PMID: 23533092 DOI: 10.1002/wnan.1220] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Surgery involves the repair, resection, replacement, or improvement of body parts and functions and in numerous ways, surgery should be considered human engineering. There are many areas in which surgical materials could be improved, but surgeons are generally unaware of materials available for use, while materials scientists do not know what surgeons require. This article will review some of the areas where surgeons and materials scientists have interacted in the past and will discuss some of the most pressing problems which remain to be solved. These include better implant materials for hernia repair, breast reconstruction, the treatment of diabetes, vascular stenting and reconstruction, and electrical pacing devices. The combination of tissue engineering and nanomaterials has great potential for application to nearly every aspect of surgery. Tissue engineering will allow cells or artificial organs to be grown for specific uses while nanotechnology will help to ensure maximal biocompatibility. Biosensors will be combined with improved electrodes and pacing devices to control impaired neurological functions.
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19
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Animal models of diabetes mellitus for islet transplantation. EXPERIMENTAL DIABETES RESEARCH 2012; 2012:256707. [PMID: 23346100 PMCID: PMC3546491 DOI: 10.1155/2012/256707] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Accepted: 12/12/2012] [Indexed: 01/09/2023]
Abstract
Due to current improvements in techniques for islet isolation and transplantation and protocols for immunosuppressants, islet transplantation has become an effective treatment for severe diabetes patients. Many diabetic animal models have contributed to such improvements. In this paper, we focus on 3 types of models with different mechanisms for inducing diabetes mellitus (DM): models induced by drugs including streptozotocin (STZ), pancreatomized models, and spontaneous models due to autoimmunity. STZ-induced diabetes is one of the most commonly used experimental diabetic models and is employed using many specimens including rodents, pigs or monkeys. The management of STZ models is well established for islet studies. Pancreatomized models reveal different aspects compared to STZ-induced models in terms of loss of function in the increase and decrease of blood glucose and therefore are useful for evaluating the condition in total pancreatomized patients. Spontaneous models are useful for preclinical studies including the assessment of immunosuppressants because such models involve the same mechanisms as type 1 DM in the clinical setting. In conclusion, islet researchers should select suitable diabetic animal models according to the aim of the study.
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20
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Domján A, Fodor C, Kovács S, Marek T, Iván B, Süvegh K. Anomalous Swelling Behavior of Poly(N-vinylimidazole)-l-Poly(tetrahydrofuran) Amphiphilic Conetwork in Water Studied by Solid-State NMR and Positron Annihilation Lifetime Spectroscopy. Macromolecules 2012. [DOI: 10.1021/ma301533g] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
| | | | - Szabolcs Kovács
- Department of Nuclear Chemistry, Eötvös Loránd Science University, P.O. Box 32, H-1518
Budapest, Hungary
| | - Tamás Marek
- Department
of Surface Modifications
and Nanostructures, Institute of Materials and Environmental Chemistry,
Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pusztaszeri u. 59-67, P.O. Box 17, H-1525
Budapest, Hungary
| | | | - Károly Süvegh
- Department of Nuclear Chemistry, Eötvös Loránd Science University, P.O. Box 32, H-1518
Budapest, Hungary
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21
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Stiegler P, Matzi V, Pierer E, Hauser O, Schaffellner S, Renner H, Greilberger J, Aigner R, Maier A, Lackner C, Iberer F, Smolle-Jüttner FM, Tscheliessnigg K, Stadlbauer V. Creation of a prevascularized site for cell transplantation in rats. Xenotransplantation 2011; 17:379-90. [PMID: 20955294 DOI: 10.1111/j.1399-3089.2010.00606.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Transplanted cells, especially islet cells, are likely to become apoptotic due to local hypoxia leading to graft dysfunction. Isolated pancreatic islet cells depend on the diffusion of oxygen from the surrounding tissue; therefore, access to sufficient oxygen supply is beneficial, particularly when microcapsules are used for immunoisolation in xenotransplantation. The aim of this study was to create a prevascularized site for cell transplantation in rats and test its effectiveness with microencapsulated HEK293 cells. METHODS The combination of implantation of a foam dressing, vacuum-assisted wound closure (foam+VAC) and hyperbaric oxygenation (HBO) was used in 40 Sprague-Dawley rats. Blood flow and vascular endothelial growth factor (VEGF) levels were determined. Sodium cellulose sulphate (SCS)-microencapsulated HEK293 cells were xenotransplanted into the foam dressing in rats pre-treated with HBO, and angiogenesis and apoptosis were assessed. RESULTS Vessel ingrowth and VEGF levels increased depending on the duration of HBO treatment. The area containing the foam was perfused significantly better in the experimental groups when compared to controls. Only a small amount of apoptosis occurs in SCS-microencapsulated HEK293 cells after xenotransplantation. CONCLUSION As ischemia-damaged cells are likely to undergo cell death or loose functionality due to hypoxia, therefore leading to graft dysfunction, the combination foam+VAC and HBO might be a promising method to create a prevascularized site to achieve better results in xenogeneic cell transplantation.
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Affiliation(s)
- Philipp Stiegler
- Department of Surgery, Division of Transplantation Surgery, Medical University Graz, Graz, Austria.
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Abstract
Clinical islet transplantation (CIT), the infusion of allogeneic islets within the liver, has the potential to provide precise and sustainable control of blood glucose levels for the treatment of type 1 diabetes. The success and long-term outcomes of CIT, however, are limited by obstacles such as a nonoptimal transplantation site and severe inflammatory and immunological responses to the transplant. Tissue engineering strategies are poised to combat these challenges. In this review, emerging methods for engineering an optimal islet transplantation site, as well as novel approaches for improving islet cell encapsulation, are discussed.
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Affiliation(s)
- Jaime A Giraldo
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, Florida, USA
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23
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Pafiti KS, Loizou E, Patrickios CS, Porcar L. End-Linked Semifluorinated Amphiphilic Polymer Conetworks: Synthesis by Sequential Reversible Addition−Fragmentation Chain Transfer Polymerization and Characterization. Macromolecules 2010. [DOI: 10.1021/ma100552v] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kyriaki S. Pafiti
- Department of Chemistry, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus
| | - Elena Loizou
- Department of Chemistry, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus
| | - Costas S. Patrickios
- Department of Chemistry, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus
| | - Lionel Porcar
- Institute Max von Laue-Paul Langevin, BP 156, F-38042 Grenoble Cedex 9, France
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Kang J, Erdodi G, Kennedy JP, Chou H, Lu L, Grundfest-Broniatowski S. Toward a Bioartificial Pancreas: Diffusion of Insulin and IgG Across Immunoprotective Membranes with Controlled Hydrophilic Channel Diameters. Macromol Biosci 2010; 10:369-77. [DOI: 10.1002/mabi.200900386] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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