1
|
Sokolowska P, Zukowski K, Janikiewicz J, Jastrzebska E, Dobrzyn A, Brzozka Z. Islet-on-a-chip: Biomimetic micropillar-based microfluidic system for three-dimensional pancreatic islet cell culture. Biosens Bioelectron 2021; 183:113215. [PMID: 33845292 DOI: 10.1016/j.bios.2021.113215] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/15/2021] [Accepted: 03/28/2021] [Indexed: 12/14/2022]
Abstract
Type 2 diabetes is currently one of the most common metabolic diseases, affecting all ages worldwide. As the incidence of type 2 diabetes increases, a growing number of studies focus on islets of Langerhans. A three-dimensional research model that maps islet morphology and maintains hormonal balance in vivo is still needed. In this work, we present an Islet-on-a-chip system, specifically a micropillar-based microfluidic platform for three-dimensional pancreatic islet cell culture and analysis. The microfluidic system consisted of two culture chambers that were equipped with 15 circular microtraps each, which were built with seven round micropillars each. Micropillars in the structure of microtraps supported cell aggregation by limiting the growth surface and minimizing wall shear stress, thereby ensuring proper medium diffusion and optimal culture conditions for cell aggregates. Our system is compatible with microwell plate readers and confocal laser scanning microscopes. Because of optimization of the immunostaining method, the appropriate cell distribution and high viability and proliferation up to 72 h of culture were confirmed. Enzyme-linked immunosorbent assays were performed to measure insulin and glucagon secretion after stimulation with different glucose concentrations. To our knowledge, this is the first Lab-on-a-chip system which enables the formation and three-dimensional culture of cell aggregates composed of commercially available α and β pancreatic islet cells. The specific composition and arrangement of cells in the obtained model corresponds to the arrangement of the cells in rodent pancreatic islets in vivo. This Islet-on-a-chip system may be utilized to test pathogenic effectors and future therapeutic agents.
Collapse
Affiliation(s)
- Patrycja Sokolowska
- Medical Biotechnology, Faculty of Chemistry, Warsaw University of Technology, Poland; Laboratory of Cell Signaling and Metabolic Disorders, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
| | - Kamil Zukowski
- Centre for Advanced Materials and Technologies CEZAMAT, Warsaw University of Technology, Poland
| | - Justyna Janikiewicz
- Laboratory of Cell Signaling and Metabolic Disorders, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
| | - Elzbieta Jastrzebska
- Medical Biotechnology, Faculty of Chemistry, Warsaw University of Technology, Poland
| | - Agnieszka Dobrzyn
- Laboratory of Cell Signaling and Metabolic Disorders, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
| | - Zbigniew Brzozka
- Medical Biotechnology, Faculty of Chemistry, Warsaw University of Technology, Poland.
| |
Collapse
|
2
|
Razavi M, Ren T, Zheng F, Telichko A, Wang J, Dahl JJ, Demirci U, Thakor AS. Facilitating islet transplantation using a three-step approach with mesenchymal stem cells, encapsulation, and pulsed focused ultrasound. Stem Cell Res Ther 2020; 11:405. [PMID: 32948247 PMCID: PMC7501701 DOI: 10.1186/s13287-020-01897-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 07/06/2020] [Accepted: 08/24/2020] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND The aim of this study was to examine the effect of a three-step approach that utilizes the application of adipose tissue-derived mesenchymal stem cells (AD-MSCs), encapsulation, and pulsed focused ultrasound (pFUS) to help the engraftment and function of transplanted islets. METHODS In step 1, islets were co-cultured with AD-MSCs to form a coating of AD-MSCs on islets: here, AD-MSCs had a cytoprotective effect on islets; in step 2, islets coated with AD-MSCs were conformally encapsulated in a thin layer of alginate using a co-axial air-flow method: here, the capsule enabled AD-MSCs to be in close proximity to islets; in step 3, encapsulated islets coated with AD-MSCs were treated with pFUS: here, pFUS enhanced the secretion of insulin from islets as well as stimulated the cytoprotective effect of AD-MSCs. RESULTS Our approach was shown to prevent islet death and preserve islet functionality in vitro. When 175 syngeneic encapsulated islets coated with AD-MSCs were transplanted beneath the kidney capsule of diabetic mice, and then followed every 3 days with pFUS treatment until day 12 post-transplantation, we saw a significant improvement in islet function with diabetic animals re-establishing glycemic control over the course of our study (i.e., 30 days). In addition, our approach was able to enhance islet engraftment by facilitating their revascularization and reducing inflammation. CONCLUSIONS This study demonstrates that our clinically translatable three-step approach is able to improve the function and viability of transplanted islets.
Collapse
Affiliation(s)
- Mehdi Razavi
- Department of Radiology, Interventional Regenerative Medicine and Imaging Laboratory, Stanford University School of Medicine, 3155 Porter Drive, Palo Alto, CA, 94304, USA
- Biionix™ (Bionic Materials, Implants & Interfaces) Cluster, Department of Internal Medicine, College of Medicine, University of Central Florida, Orlando, FL, 32827, USA
- Department of Materials Science and Engineering, University of Central Florida, Orlando, FL, 32816, USA
| | - Tanchen Ren
- Department of Radiology, Bio-Acoustic MEMS in Medicine Laboratory (BAMM), Stanford University School of Medicine, Palo Alto, CA, 94304, USA
| | - Fengyang Zheng
- Department of Radiology, Interventional Regenerative Medicine and Imaging Laboratory, Stanford University School of Medicine, 3155 Porter Drive, Palo Alto, CA, 94304, USA
| | - Arsenii Telichko
- Department of Radiology, Dahl Ultrasound Laboratory, Stanford University School of Medicine, Palo Alto, CA, 94304, USA
| | - Jing Wang
- Department of Radiology, Interventional Regenerative Medicine and Imaging Laboratory, Stanford University School of Medicine, 3155 Porter Drive, Palo Alto, CA, 94304, USA
| | - Jeremy J Dahl
- Department of Radiology, Dahl Ultrasound Laboratory, Stanford University School of Medicine, Palo Alto, CA, 94304, USA
| | - Utkan Demirci
- Department of Radiology, Bio-Acoustic MEMS in Medicine Laboratory (BAMM), Stanford University School of Medicine, Palo Alto, CA, 94304, USA
| | - Avnesh S Thakor
- Department of Radiology, Interventional Regenerative Medicine and Imaging Laboratory, Stanford University School of Medicine, 3155 Porter Drive, Palo Alto, CA, 94304, USA.
| |
Collapse
|
3
|
Lau H, Corrales N, Alexander M, Mohammadi MR, Li S, Smink AM, de Vos P, Lakey JRT. Necrostatin-1 supplementation enhances young porcine islet maturation and in vitro function. Xenotransplantation 2019; 27:e12555. [PMID: 31532037 DOI: 10.1111/xen.12555] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 08/13/2019] [Accepted: 08/28/2019] [Indexed: 12/12/2022]
Abstract
BACKGROUND Necroptosis has been demonstrated to be a primary mechanism of islet cell death. This study evaluated whether the supplementation of necrostatin-1 (Nec-1), a potent inhibitor of necroptosis, to islet culture media could improve the recovery, maturation, and function of pre-weaned porcine islets (PPIs). METHODS PPIs were isolated from pre-weaned Yorkshire piglets (8-15 days old) and either cultured in control islet culture media (n = 6) or supplemented with Nec-1 (100 µM, n = 5). On days 3 and 7 of culture, islets were assessed for recovery, insulin content, viability, cellular composition, GLUT2 expression in beta cells, differentiation of pancreatic endocrine progenitor cells, function, and oxygen consumption rate. RESULTS Nec-1 supplementation induced a 2-fold increase in the insulin content of PPIs on day 7 of culture. When compared to untreated islets, Nec-1 treatment doubled the beta- and alpha-cell composition and accelerated the development of delta cells. Additionally, beta cells of Nec-1-treated islets had a significant upregulation in GLUT2 expression. The enhanced development of major endocrine cells and GLUT2 expression after Nec-1 treatment subsequently led to a significant increase in the amount of insulin secreted in response to in vitro glucose challenge. Islet recovery, viability, and oxygen consumption rate were unaffected by Nec-1. CONCLUSION This study underlines the importance of necroptosis in islet cell death after isolation and demonstrates the novel effects of Nec-1 to increase islet insulin content, enhance pancreatic endocrine cell development, facilitate GLUT2 upregulation in beta cells, and augment insulin secretion. Nec-1 supplementation to culture media significantly improves islet quality prior to xenotransplantation.
Collapse
Affiliation(s)
- Hien Lau
- Department of Surgery, University of California Irvine, Irvine, CA, USA
| | - Nicole Corrales
- Department of Surgery, University of California Irvine, Irvine, CA, USA
| | - Michael Alexander
- Department of Surgery, University of California Irvine, Irvine, CA, USA
| | - Mohammad Rezaa Mohammadi
- Department of Chemical Engineering and Materials Science, Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA, USA.,Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, USA
| | - Shiri Li
- Department of Surgery, University of California Irvine, Irvine, CA, USA
| | - Alexandra M Smink
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Paul de Vos
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jonathan R T Lakey
- Department of Surgery, University of California Irvine, Irvine, CA, USA.,Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, USA
| |
Collapse
|
4
|
Kim J, Shim IK, Hwang DG, Lee YN, Kim M, Kim H, Kim SW, Lee S, Kim SC, Cho DW, Jang J. 3D cell printing of islet-laden pancreatic tissue-derived extracellular matrix bioink constructs for enhancing pancreatic functions. J Mater Chem B 2019; 7:1773-1781. [PMID: 32254919 DOI: 10.1039/c8tb02787k] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Type 1 diabetes mellitus (T1DM) is a form of diabetes that inhibits or halts insulin production in the pancreas. Although various therapeutic options are applied in clinical settings, not all patients are treatable with such methods due to the instability of the T1DM or the unawareness of hypoglycemia. Islet transplantation using a tissue engineering-based approach may mark a clinical significance, but finding ways to increase the function of islets in 3D constructs is a major challenge. In this study, we suggest pancreatic tissue-derived extracellular matrix as a potential candidate to recapitulate the native microenvironment in transplantable 3D pancreatic tissues. Notably, insulin secretion and the maturation of insulin-producing cells derived from human pluripotent stem cells were highly up-regulated when cultured in pdECM bioink. In addition, co-culture with human umbilical vein-derived endothelial cells decreased the central necrosis of islets under 3D culture conditions. Through the convergence of 3D cell printing technology, we validated the possibility of fabricating 3D constructs of a therapeutically applicable transplant size that can potentially be an allogeneic source of islets, such as patient-induced pluripotent stem cell-derived insulin-producing cells.
Collapse
Affiliation(s)
- Jaewook Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Korea.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Najafikhah N, Hashemi-Najafabadi S, Zahediasl S, Nabavimanesh MM, Farrokhfall K. Normal Insulin Secretion from Immune-Protected Islets of Langerhans by PEGylation and Encapsulation in the Alginate-Chitosan-PEG. Iran J Biotechnol 2018; 16:e1669. [PMID: 31457032 PMCID: PMC6697838 DOI: 10.21859/ijb.1669] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 05/04/2018] [Accepted: 06/17/2018] [Indexed: 12/26/2022]
Abstract
Background Pancreatic islet transplantation is one of the most promising strategies for treating patients with type I diabetes mellitus. Objective We aimed to assess the immunoisolation properties of the multilayer encapsulated islets using alginate-chitosan-PEG for immunoprotection and insulin secretion from the encapsulated islets induced under different glucose concentrations in vitro. Materials and Methods In this study, the islets were isolated from Wistar rats. The biological function (insulin secretion) of the immunoisolated islets following to PEGylation and encapsulation in the alginate-chitosan-PEG, separately, in addition to their immuno-protection in a co-culturing with the lymphocytes isolated from the male C57BL/6 mice were investigated, respectively. Results Alginate-chitosan-PEG decreased IL-2 secretion from the lymphocytes co-cultured with islets. Also, insulin secretion from the encapsulated and PEGylated groups was stimulated by glucose (i.e., 5.6 and 16.7 mM of glucose, respectively); showed insulin secretion similar to the naked islets, without coating, after 30 and 60 min of incubation. Conclusion In conclusion, encapsulation and PEGylation have no negative effect on the insulin secretion and glucose sensitivity of the islets for all of the groups. Also, encapsulation decreased IL-2 secretion from the lymphocytes.
Collapse
Affiliation(s)
- Nahid Najafikhah
- Biomedical Engineering Department, Faculty of Chemical Engineering, Tarbiat Modares University, Tehran, Iran
| | - Sameereh Hashemi-Najafabadi
- Biomedical Engineering Department, Faculty of Chemical Engineering, Tarbiat Modares University, Tehran, Iran
| | - Saleh Zahediasl
- Endocrine Research Center, Research Institute of Endocrine Sciences, Shaheed Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Mahdi Nabavimanesh
- Biomedical Engineering Department, Faculty of Chemical Engineering, Tarbiat Modares University, Tehran, Iran
| | - Khadijeh Farrokhfall
- Medical Toxicology and Drug Abuse Research Center (MTDR C), Birjand University of Medical Sciences, Birjand, Iran
| |
Collapse
|
6
|
Perez-Basterrechea M, Esteban MM, Vega JA, Obaya AJ. Tissue-engineering approaches in pancreatic islet transplantation. Biotechnol Bioeng 2018; 115:3009-3029. [PMID: 30144310 DOI: 10.1002/bit.26821] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 08/08/2018] [Accepted: 08/14/2018] [Indexed: 12/15/2022]
Abstract
Pancreatic islet transplantation is a promising alternative to whole-pancreas transplantation as a treatment of type 1 diabetes mellitus. This technique has been extensively developed during the past few years, with the main purpose of minimizing the complications arising from the standard protocols used in organ transplantation. By using a variety of strategies used in tissue engineering and regenerative medicine, pancreatic islets have been successfully introduced in host patients with different outcomes in terms of islet survival and functionality, as well as the desired normoglycemic control. Here, we describe and discuss those strategies to transplant islets together with different scaffolds, in combination with various cell types and diffusible factors, and always with the aim of reducing host immune response and achieving islet survival, regardless of the site of transplantation.
Collapse
Affiliation(s)
- Marcos Perez-Basterrechea
- Unidad de Terapia Celular y Medicina Regenerativa, Servicio de Hematología y Hemoterapia, Hospital Universitario Central de Asturias (HUCA), Oviedo, Spain.,Plataforma de Terapias Avanzadas, Instituto de Investigación Biosanitaria del Principado de Asturias (ISPA), Oviedo, Spain
| | - Manuel M Esteban
- Departamento de Biología Funcional, Universidad de Oviedo, Oviedo, Spain
| | - Jose A Vega
- Departamento de Morfología y Biología Celular, Universidad de Oviedo, Oviedo, Spain.,Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile
| | - Alvaro J Obaya
- Departamento de Biología Funcional, Universidad de Oviedo, Oviedo, Spain
| |
Collapse
|
7
|
Lew B, Kim IY, Choi H, Kim K. Sustained exenatide delivery via intracapsular microspheres for improved survival and function of microencapsulated porcine islets. Drug Deliv Transl Res 2018; 8:857-862. [DOI: 10.1007/s13346-018-0484-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
8
|
Sarkis S, Silencieux F, Markwick KE, Fortin MA, Hoesli CA. Magnetic Resonance Imaging of Alginate Beads Containing Pancreatic Beta Cells and Paramagnetic Nanoparticles. ACS Biomater Sci Eng 2017; 3:3576-3587. [DOI: 10.1021/acsbiomaterials.7b00404] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Sary Sarkis
- Department
of Chemical Engineering, McGill University, Wong Building, 3610 University Street, Montreal, QC H3A
0C5, Canada
| | - Fanny Silencieux
- Laboratoire
de Biomatériaux pour l’Imagerie médicale, Axe
Médecine Régénératrice, Centre de recherche du Centre hospitalier universitaire de Québec (CR-CHU de Québec), 10 rue de l’Espinay, Québec
City, QC G1L 3L5, Canada
- Centre
de recherche sur les matériaux avancés (CERMA), Université Laval, Pavillon Vachon, 1065 avenue de la Médecine, Québec City, QC G1V 0A6, Canada
- Département
de Génie des Mines, de la Métallurgie et des Matériaux, Université Laval, Pavillon Pouliot, 1065 avenue de la Médecine, Québec City, QC G1V 0A6, Canada
| | - Karen E. Markwick
- Department
of Chemical Engineering, McGill University, Wong Building, 3610 University Street, Montreal, QC H3A
0C5, Canada
| | - Marc-André Fortin
- Laboratoire
de Biomatériaux pour l’Imagerie médicale, Axe
Médecine Régénératrice, Centre de recherche du Centre hospitalier universitaire de Québec (CR-CHU de Québec), 10 rue de l’Espinay, Québec
City, QC G1L 3L5, Canada
- Centre
de recherche sur les matériaux avancés (CERMA), Université Laval, Pavillon Vachon, 1065 avenue de la Médecine, Québec City, QC G1V 0A6, Canada
- Département
de Génie des Mines, de la Métallurgie et des Matériaux, Université Laval, Pavillon Pouliot, 1065 avenue de la Médecine, Québec City, QC G1V 0A6, Canada
| | - Corinne A. Hoesli
- Department
of Chemical Engineering, McGill University, Wong Building, 3610 University Street, Montreal, QC H3A
0C5, Canada
| |
Collapse
|
9
|
Caddeo S, Boffito M, Sartori S. Tissue Engineering Approaches in the Design of Healthy and Pathological In Vitro Tissue Models. Front Bioeng Biotechnol 2017; 5:40. [PMID: 28798911 PMCID: PMC5526851 DOI: 10.3389/fbioe.2017.00040] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 06/26/2017] [Indexed: 12/16/2022] Open
Abstract
In the tissue engineering (TE) paradigm, engineering and life sciences tools are combined to develop bioartificial substitutes for organs and tissues, which can in turn be applied in regenerative medicine, pharmaceutical, diagnostic, and basic research to elucidate fundamental aspects of cell functions in vivo or to identify mechanisms involved in aging processes and disease onset and progression. The complex three-dimensional (3D) microenvironment in which cells are organized in vivo allows the interaction between different cell types and between cells and the extracellular matrix, the composition of which varies as a function of the tissue, the degree of maturation, and health conditions. In this context, 3D in vitro models can more realistically reproduce a tissue or organ than two-dimensional (2D) models. Moreover, they can overcome the limitations of animal models and reduce the need for in vivo tests, according to the "3Rs" guiding principles for a more ethical research. The design of 3D engineered tissue models is currently in its development stage, showing high potential in overcoming the limitations of already available models. However, many issues are still opened, concerning the identification of the optimal scaffold-forming materials, cell source and biofabrication technology, and the best cell culture conditions (biochemical and physical cues) to finely replicate the native tissue and the surrounding environment. In the near future, 3D tissue-engineered models are expected to become useful tools in the preliminary testing and screening of drugs and therapies and in the investigation of the molecular mechanisms underpinning disease onset and progression. In this review, the application of TE principles to the design of in vitro 3D models will be surveyed, with a focus on the strengths and weaknesses of this emerging approach. In addition, a brief overview on the development of in vitro models of healthy and pathological bone, heart, pancreas, and liver will be presented.
Collapse
Affiliation(s)
- Silvia Caddeo
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
- Department of Oral Cell Biology, Academic Center for Dentistry Amsterdam, Amsterdam, Netherlands
| | - Monica Boffito
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Susanna Sartori
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| |
Collapse
|
10
|
Hoesli CA, Kiang RLJ, Raghuram K, Pedroza RG, Markwick KE, Colantuoni AMR, Piret JM. Mammalian Cell Encapsulation in Alginate Beads Using a Simple Stirred Vessel. J Vis Exp 2017:55280. [PMID: 28715390 PMCID: PMC5608521 DOI: 10.3791/55280] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Cell encapsulation in alginate beads has been used for immobilized cell culture in vitro as well as for immunoisolation in vivo. Pancreatic islet encapsulation has been studied extensively as a means to increase islet survival in allogeneic or xenogeneic transplants. Alginate encapsulation is commonly achieved by nozzle extrusion and external gelation. Using this method, cell-containing alginate droplets formed at the tip of nozzles fall into a solution containing divalent cations that cause ionotropic alginate gelation as they diffuse into the droplets. The requirement for droplet formation at the nozzle tip limits the volumetric throughput and alginate concentration that can be achieved. This video describes a scalable emulsification method to encapsulate mammalian cells in 0.5% to 10% alginate with 70% to 90% cell survival. By this alternative method, alginate droplets containing cells and calcium carbonate are emulsified in mineral oil, followed by a decrease in pH leading to internal calcium release and ionotropic alginate gelation. The current method allows the production of alginate beads within 20 min of emulsification. The equipment required for the encapsulation step consists in simple stirred vessels available to most laboratories.
Collapse
Affiliation(s)
| | - Roger L J Kiang
- Michael Smith Laboratories & Department of Chemical and Biological Engineering, University of British Columbia
| | - Kamini Raghuram
- Michael Smith Laboratories & Department of Chemical and Biological Engineering, University of British Columbia
| | - René G Pedroza
- Michael Smith Laboratories & Department of Pharmaceutical Sciences, University of British Columbia
| | | | | | - James M Piret
- Michael Smith Laboratories & Department of Chemical and Biological Engineering, University of British Columbia
| |
Collapse
|
11
|
Emerich DF, Thanos CG. In Vitro Culture Duration does Not Impact the Ability of Encapsulated Choroid Plexus Transplants to Prevent Neurological Deficits in an Excitotoxin-Lesioned Rat Model of Huntington's Disease. Cell Transplant 2017; 15:595-602. [PMID: 17176611 DOI: 10.3727/000000006783981657] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Delivery of neurotrophic molecules to the CNS is a potential treatment strategy for preventing the neuronal loss accompanying many neurological disorders. Choroid plexus (CP) epithelial cells secrete a cocktail of neurotrophic factors, and encapsulated CP transplants are neuroprotective in animal models of stroke and Huntington's disease (HD). Prior to clinical use, it is essential to identify and optimize parameters such as the length of time that transplant products such as encapsulated CP can be maintained. In the present study, neonatal porcine CP was encapsulated within alginate microcapsules and maintained in vitro for 1, 2, or 7 months. The encapsulated cells remained viable (>80%) at all time points and were transplanted unilaterally into the rat striatum. Seven days later, the same animals received unilateral injections of quinolinic acid (QA; 225 nmol) adjacent to the implant site. Separate groups of animals served as controls and received QA alone. After surgery, animals were periodically evaluated for weight loss and were tested for motor function 14 days post-QA. In controls, QA lesions produced a significant loss of body weight and impaired function of the contralateral forelimb. In contrast, implants of CP were potently neuroprotective as rats receiving CP transplants did not lose body weight and were not significantly impaired when tested for motor function. These benefits were independent of the length of time that the cells were held in vitro and demonstrate that the potential potency of alginate encapsulated CP cells can be retained for extremely long periods of time in vitro.
Collapse
|
12
|
Tasciotti E, Cabrera FJ, Evangelopoulos M, Martinez JO, Thekkedath UR, Kloc M, Ghobrial RM, Li XC, Grattoni A, Ferrari M. The Emerging Role of Nanotechnology in Cell and Organ Transplantation. Transplantation 2016; 100:1629-38. [PMID: 27257995 DOI: 10.1097/TP.0000000000001100] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Transplantation is often the only choice many patients have when suffering from end-stage organ failure. Although the quality of life improves after transplantation, challenges, such as organ shortages, necessary immunosuppression with associated complications, and chronic graft rejection, limit its wide clinical application. Nanotechnology has emerged in the past 2 decades as a field with the potential to satisfy clinical needs in the area of targeted and sustained drug delivery, noninvasive imaging, and tissue engineering. In this article, we provide an overview of popular nanotechnologies and a summary of the current and potential uses of nanotechnology in cell and organ transplantation.
Collapse
|
13
|
Lepekhova SA, Goldberg OA, Kravchenko AA, Batraks AE, Koval EV, Kurgansky IS, Apartsin KA. A Method for Microencapsulation of Cells and a Device for Its Realization. Bull Exp Biol Med 2017; 162:820-823. [PMID: 28429231 DOI: 10.1007/s10517-017-3721-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Indexed: 10/19/2022]
Abstract
The device for cell encapsulation makes it possible to fabricate microcapsules of a preset size with even smooth surface, without defects or adhesion to each other, with viable cells inside the capsule. The cells were derived from newborn piglet pancreases.
Collapse
Affiliation(s)
- S A Lepekhova
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia. .,Irkutsk Research Center, Siberian Division of the Russian Academy of Sciences, Irkutsk, Russia. .,Irkutsk State Medical University, Ministry of Health of the Russian Federation, Irkutsk, Russia.
| | - O A Goldberg
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia
| | - A A Kravchenko
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia
| | - A E Batraks
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia
| | - E V Koval
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia
| | - I S Kurgansky
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia
| | - K A Apartsin
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia.,Irkutsk Research Center, Siberian Division of the Russian Academy of Sciences, Irkutsk, Russia.,Irkutsk State Medical University, Ministry of Health of the Russian Federation, Irkutsk, Russia
| |
Collapse
|
14
|
Hood RL, Hood GD, Ferrari M, Grattoni A. Pioneering medical advances through nanofluidic implantable technologies. WIREs Nanomed Nanobiotechnol 2017; 9. [DOI: 10.1002/wnan.1455] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 11/27/2016] [Accepted: 12/17/2016] [Indexed: 12/11/2022]
Affiliation(s)
- R. Lyle Hood
- Department of Nanomedicine; Houston Methodist Research Institute; Houston TX USA
- Department of Mechanical Engineering; University of Texas San Antonio; San Antonio TX USA
| | - Gold Darr Hood
- Department of Nanomedicine; Houston Methodist Research Institute; Houston TX USA
| | - Mauro Ferrari
- Department of Nanomedicine; Houston Methodist Research Institute; Houston TX USA
| | - Alessandro Grattoni
- Department of Nanomedicine; Houston Methodist Research Institute; Houston TX USA
| |
Collapse
|
15
|
Gao B, Wang L, Han S, Pingguan-Murphy B, Zhang X, Xu F. Engineering of microscale three-dimensional pancreatic islet models in vitro and their biomedical applications. Crit Rev Biotechnol 2015; 36:619-29. [PMID: 25669871 DOI: 10.3109/07388551.2014.1002381] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Diabetes now is the most common chronic disease in the world inducing heavy burden for the people's health. Based on this, diabetes research such as islet function has become a hot topic in medical institutes of the world. Today, in medical institutes, the conventional experiment platform in vitro is monolayer cell culture. However, with the development of micro- and nano-technologies, several microengineering methods have been developed to fabricate three-dimensional (3D) islet models in vitro which can better mimic the islet of pancreases in vivo. These in vitro islet models have shown better cell function than monolayer cells, indicating their great potential as better experimental platforms to elucidate islet behaviors under both physiological and pathological conditions, such as the molecular mechanisms of diabetes and clinical islet transplantation. In this review, we present the state-of-the-art advances in the microengineering methods for fabricating microscale islet models in vitro. We hope this will help researchers to better understand the progress in the engineering 3D islet models and their biomedical applications such as drug screening and islet transplantation.
Collapse
Affiliation(s)
- Bin Gao
- a The Key Laboratory of Biomedical Information Engineering of Ministry of Education , Xi'an Jiaotong University School of Life Science and Technology , Xi'an , China .,b Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University , Xi'an , China .,c Department of Endocrinology and Metabolism , Xijing Hospital, Fourth Military Medical University , Xi'an , China
| | - Lin Wang
- a The Key Laboratory of Biomedical Information Engineering of Ministry of Education , Xi'an Jiaotong University School of Life Science and Technology , Xi'an , China .,b Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University , Xi'an , China
| | - Shuang Han
- d Institute of Digestive Disease, Xijing Hospital, Fourth Military Medical University , Xi'an , China , and
| | - Belinda Pingguan-Murphy
- e Department of Biomedical Engineering, Faculty of Engineering , University of Malaya , Kuala Lumpur , Malaysia
| | - Xiaohui Zhang
- a The Key Laboratory of Biomedical Information Engineering of Ministry of Education , Xi'an Jiaotong University School of Life Science and Technology , Xi'an , China .,b Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University , Xi'an , China
| | - Feng Xu
- a The Key Laboratory of Biomedical Information Engineering of Ministry of Education , Xi'an Jiaotong University School of Life Science and Technology , Xi'an , China .,b Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University , Xi'an , China
| |
Collapse
|
16
|
Kuehn C, Fülöp T, Lakey JRT, Vermette P. Young porcine endocrine pancreatic islets cultured in fibrin and alginate gels show improved resistance towards human monocytes. ACTA ACUST UNITED AC 2014; 62:354-64. [PMID: 25239278 DOI: 10.1016/j.patbio.2014.07.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 07/29/2014] [Indexed: 12/17/2022]
Abstract
AIM To investigate the protective function of alginate and fibrin gels used to embed porcine endocrine pancreatic islets towards human monocytes. METHODS Groups of 200 islet equivalents from young pigs were embedded in either a fibrin or in an alginate gel, and as a control seeded in tissue culture polystyrene (TCPS) well plates. The islet cultures were incubated with 2×10(5) human monocytes for 24h. In addition, both islets and monocytes were separately cultured in TCPS, fibrin and alginate. Islet morphology, viability and function were investigated as well as the secretion of cytokines TNFα, IL-6, and IL-1β. RESULTS When freely-floating in TCPS, non-encapsulated islets were surrounded by monocytes and started to disperse after 24h. In fibrin, monocytes could be found in close proximity to embedded islets, indicating monocyte migration through the gel. In contrast, after 24h, few monocytes were found close to islets in alginate. Immunofluorescence staining and manual counting showed that integrin expression was higher in fibrin-embedded islet cultures. A TUNEL assay revealed elevated numbers of apoptotic cells for islets in TCPS wells compared to fibrin and alginate cultures. Insulin secretion was higher with islets embedded in fibrin and alginate when compared to non-encapsulated islets. TNFα, IL-6 and IL-1β were found in high concentrations in the media of co-cultures and monocyte mono-culture in fibrin. CONCLUSION Both alginate and fibrin provide key structural support and offer some protection for the islets towards human monocytes. Fibrin itself triggers the cytokine secretion from monocytes.
Collapse
Affiliation(s)
- C Kuehn
- Laboratoire de bio-ingénierie et de biophysique de l'Université de Sherbrooke, Department of Chemical and Biotechnological Engineering, Université de Sherbrooke, 2500, boulevard de l'Université, J1K 2R1 Sherbrooke, Québec, Canada; Research Centre on Aging, Institut universitaire de gériatrie de Sherbrooke, 1036, rue Belvédère Sud, J1H 4C4 Sherbrooke, Québec, Canada
| | - T Fülöp
- Research Centre on Aging, Institut universitaire de gériatrie de Sherbrooke, 1036, rue Belvédère Sud, J1H 4C4 Sherbrooke, Québec, Canada
| | - J R T Lakey
- Department of Surgery and Biomedical Engineering, University of California, Irvine, 333 City Boulevard West, Suite 700, Orange, 92868 CA, United States
| | - P Vermette
- Laboratoire de bio-ingénierie et de biophysique de l'Université de Sherbrooke, Department of Chemical and Biotechnological Engineering, Université de Sherbrooke, 2500, boulevard de l'Université, J1K 2R1 Sherbrooke, Québec, Canada; Research Centre on Aging, Institut universitaire de gériatrie de Sherbrooke, 1036, rue Belvédère Sud, J1H 4C4 Sherbrooke, Québec, Canada.
| |
Collapse
|
17
|
Orlando G, Gianello P, Salvatori M, Stratta RJ, Soker S, Ricordi C, Domínguez-Bendala J. Cell replacement strategies aimed at reconstitution of the β-cell compartment in type 1 diabetes. Diabetes 2014; 63:1433-44. [PMID: 24757193 DOI: 10.2337/db13-1742] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Emerging technologies in regenerative medicine have the potential to restore the β-cell compartment in diabetic patients, thereby overcoming the inadequacies of current treatment strategies and organ supply. Novel approaches include: 1) Encapsulation technology that protects islet transplants from host immune surveillance; 2) stem cell therapies and cellular reprogramming, which seek to regenerate the depleted β-cell compartment; and 3) whole-organ bioengineering, which capitalizes on the innate properties of the pancreas extracellular matrix to drive cellular repopulation. Collaborative efforts across these subfields of regenerative medicine seek to ultimately produce a bioengineered pancreas capable of restoring endocrine function in patients with insulin-dependent diabetes.
Collapse
|
18
|
Kuehn C, Vermette P, Fülöp T. Cross talk between the extracellular matrix and the immune system in the context of endocrine pancreatic islet transplantation. A review article. ACTA ACUST UNITED AC 2014; 62:67-78. [DOI: 10.1016/j.patbio.2014.01.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 01/31/2014] [Indexed: 12/14/2022]
|
19
|
Abstract
AIM To study the protective effect of a fibrin scaffold toward embedded young porcine endocrine pancreatic islets from hydrogen peroxide within the context of islet encapsulation in transplantation. METHODS After isolation and in vitro maturation, groups of 200 young porcine islet equivalents (IEQ) were embedded in a 200 µL fibrin gel and exposed to 2 concentrations (10 and 100 µM) of hydrogen peroxide (H2O2) to investigate the ability of fibrin to protect islets against apoptotic stimuli. As a control, young porcine islets were seeded in tissue culture polystyrene (TCPS) well plates and exposed to the same H2O2 concentrations. Islet integrity, viability and function were then investigated. RESULTS Morphologically, the integrity of islets embedded in fibrin gels was better preserved compared with that of islets cultured in TCPS plates, when exposed to H2O2. Immunofluorescence staining showed that insulin and glucagon expression was higher in islets cultured in fibrin. Overall, H2O2 incubation led to decreased insulin and glucagon expression. A TUNEL assay revealed elevated numbers of apoptotic cells for islets cultured in TCPS plates when compared with those embedded in fibrin. Islets cultured in TCPS plates and exposed to H2O2 had diminished ability to secrete insulin in response to glucose stimulation, whereas islets embedded in fibrin maintained their glucose responsiveness. Insulin trapped in fibrin was extracted and quantified, revealing insulin in the extract. CONCLUSIONS/INTERPRETATION Fibrin has a protective effect on young porcine endocrine pancreatic islets exposed to hydrogen peroxide.
Collapse
Affiliation(s)
- Carina Kuehn
- Laboratoire de bio-ingénierie et de biophysique de l’Université de Sherbrooke; Department of Chemical and Biotechnological Engineering; Université de Sherbrooke; Sherbrooke, Québec, Canada
- Research Centre on Aging; Institut universitaire de gériatrie de Sherbrooke; Sherbrooke, Québec, Canada
| | - Jonathan RT Lakey
- Department of Surgery and Biomedical Engineering; University of California, Irvine; Irvine, CA USA
| | - Morgan W Lamb
- Department of Surgery and Biomedical Engineering; University of California, Irvine; Irvine, CA USA
| | - Patrick Vermette
- Laboratoire de bio-ingénierie et de biophysique de l’Université de Sherbrooke; Department of Chemical and Biotechnological Engineering; Université de Sherbrooke; Sherbrooke, Québec, Canada
- Research Centre on Aging; Institut universitaire de gériatrie de Sherbrooke; Sherbrooke, Québec, Canada
- Correspondence to: Patrick Vermette,
| |
Collapse
|
20
|
Li Z, Sun H, Zhang J, Zhang H, Meng F, Cui Z. Development of in vitro 3D TissueFlex® islet model for diabetic drug efficacy testing. PLoS One 2013; 8:e72612. [PMID: 23977329 PMCID: PMC3744493 DOI: 10.1371/journal.pone.0072612] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 07/12/2013] [Indexed: 11/19/2022] Open
Abstract
Increasing individuals diagnosed with type II diabetes pose a strong demand for the development of more effective anti-diabetic drugs. However, expensive, ethically controversial animal-based screening for anti-diabetic compounds is not always predictive of the human response. The use of in vitro cell-based models in research presents obviously ethical and cost advantages over in vivo models. This study was to develop an in vitro three-dimensional (3D) perfused culture model of islets (Islet TF) for maintaining viability and functionality longer for diabetic drug efficacy tests. Briefly fresh isolated rat islets were encapsulated in ultrapure alginate and the encapsulated islets were cultured in TissueFlex(®), a multiple, parallel perfused microbioreactor system for 7 days. The encapsulated islets cultured statically in cell culture plates (3D static) and islets cultured in suspension (2D) were used as the comparisons. In this study we demonstrate for the first time that Islet TF model can maintain the in vitro islet viability, and more importantly, the elevated functionality in terms of insulin release and dynamic responses over a 7-day culture period. The Islet TF displays a high sensitivity in responding to drugs and drug dosages over conventional 2D and 3D static models. Actual drug administration in clinics could be simulated using the developed Islet TF model, and the patterns of insulin release response to the tested drugs were in agreement with the data obtained in vivo. Islet TF could be a more predictive in vitro model for routine short- and long-term anti-diabetic drug efficacy testing.
Collapse
Affiliation(s)
- Zhaohui Li
- Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom
| | - He Sun
- Tianjin Weikai Bioeng Ltd, Tianjin, China
| | | | | | - Fanyu Meng
- Tianjin Weikai Bioeng Ltd, Tianjin, China
| | - Zhanfeng Cui
- Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
21
|
Abstract
Cell encapsulation is a method of encasing cells in a semipermeable matrix that provides a permeable gradient for the passage of oxygen and nutrients, but effectively blocks immune-regulating cells from reaching the graft, preventing rejection. This concept has been described as early as the 1930s, but it has exhibited substantial achievements over the last decade. Several advances in encapsulation engineering, chemical purification, applications, and cell viability promise to make this a revolutionary technology. Several obstacles still need to be overcome before this process becomes a reality, including developing a reliable source of islets or insulin-producing cells, determining the ideal biomaterial to promote graft function, reducing the host response to the encapsulation device, and ultimately a streamlined, scaled-up process for industry to be able to efficiently and safely produce encapsulated cells for clinical use. This article provides a comprehensive review of cell encapsulation of islets for the treatment of type 1 diabetes, including a historical perspective, current research findings, and future studies.
Collapse
Affiliation(s)
- Lourdes Robles
- Department of Surgery, University of California Irvine, Irvine, CA, USA
| | | | | | | | | |
Collapse
|
22
|
Qi M, Mørch Y, Lacík I, Formo K, Marchese E, Wang Y, Danielson KK, Kinzer K, Wang S, Barbaro B, Kolláriková G, Chorvát D, Hunkeler D, Skjåk-Braek G, Oberholzer J, Strand BL. Survival of human islets in microbeads containing high guluronic acid alginate crosslinked with Ca2+ and Ba2+. Xenotransplantation 2013. [PMID: 23198731 DOI: 10.1111/xen.12009] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND The main hurdles to the widespread use of islet transplantation for the treatment of type 1 diabetes continue to be the insufficient number of appropriate donors and the need for immunosuppression. Microencapsulation has been proposed as a means to protect transplanted islets from the host's immune system. METHODS This study investigated the function of human pancreatic islets encapsulated in Ca(2+) /Ba(2+) -alginate microbeads intraperitoneally transplanted in diabetic Balb/c mice. RESULTS All mice transplanted with encapsulated human islets (n = 29), at a quantity of 3000 islet equivalent (IEQ), achieved normoglycemia 1 day after transplantation and retained normoglycemia for extended periods of time (mean graft survival 134 ± 17 days). In comparison, diabetic Balb/c mice transplanted with an equal amount of non-encapsulated human islets rejected the islets within 2 to 7 days after transplantation (n = 5). Microbeads retrieved after 232 days (n = 3) were found with little to no fibrotic overgrowth and contained viable insulin-positive islets. Immunofluorescent staining on the retrieved microbeads showed F4/80-positive macrophages and alpha smooth muscle actin-positive fibroblasts but no CD3-positive T lymphocytes. CONCLUSIONS The Ca(2+) /Ba(2+) -alginate microbeads can protect human islets from xenogeneic rejection in immunocompetent mice without immunosuppression. However, grafts ultimately failed likely secondary to a macrophage-mediated foreign body reaction.
Collapse
Affiliation(s)
- Meirigeng Qi
- Department of Transplant/Surgery, University of Illinois at Chicago, Chicago, IL 60612, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Holdcraft RW, Gazda LS, Circle L, Adkins H, Harbeck SG, Meyer ED, Bautista MA, Martis PC, Laramore MA, Vinerean HV, Hall RD, Smith BH. Enhancement of in vitro and in vivo function of agarose-encapsulated porcine islets by changes in the islet microenvironment. Cell Transplant 2013; 23:929-44. [PMID: 23635430 DOI: 10.3727/096368913x667033] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The transplantation of porcine islets of Langerhans to treat type 1 diabetes may provide a solution to the demand for insulin-producing cells. Porcine islets encapsulated in agarose-agarose macrobeads have been shown to function in nonimmunosuppressed xenogeneic models of both streptozotocin-induced and autoimmune type 1 diabetes. One advantage of agarose encapsulation is the ability to culture macrobeads for extended periods, permitting microbiological and functional assessment. Herein we describe optimization of the agarose matrix that results in improved islet function. Porcine islets (500 IEQs) from retired breeding sows were encapsulated in 1.5% SeaKem Gold (SG), 0.8% SG, or 0.8% Litex (Li) agarose, followed by an outer capsule of 5% SG agarose. Insulin production by the encapsulated islets exhibited an agarose-specific effect with 20% (0.8% SG) to 50% (0.8% Li) higher initial insulin production relative to 1.5% SG macrobeads. Insulin production was further increased by 40-50% from week 2 to week 12 in both agarose types at the 0.8% concentration, whereas islets encapsulated in 1.5% SG agarose increased insulin production by approximately 20%. Correspondingly, fewer macrobeads were required to restore normoglycemia in streptozotocin-induced diabetic female CD(SD) rats that received 0.8% Li (15 macrobeads) or 0.8% SG (17 macrobeads) as compared to 1.5% SG (19 macrobeads). Islet cell proliferation was also observed during the first 2 months postencapsulation, peaking at 4 weeks, where approximately 50% of islets contained proliferative cells, including β-cells, regardless of agarose type. These results illustrate the importance of optimizing the microenvironment of encapsulated islets to improve islet performance and advance the potential of islet xenotransplantation for the treatment of type 1 diabetes.
Collapse
|
24
|
Dufrane D, Gianello P. Macro- or microencapsulation of pig islets to cure type 1 diabetes. World J Gastroenterol 2012; 18:6885-93. [PMID: 23322985 PMCID: PMC3531671 DOI: 10.3748/wjg.v18.i47.6885] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 06/14/2012] [Accepted: 06/28/2012] [Indexed: 02/06/2023] Open
Abstract
Although allogeneic islet transplantation can successfully cure type 1 diabetes, it has limited applicability. For example, organs are in short supply; several human pancreas donors are often needed to treat one diabetic recipient; the intrahepatic site may not be the most appropriate site for islet implantation; and immunosuppressive regimens, which are associated with side effects, are often required to prolong survival of the islet graft. An alternative source of insulin-producing cells would therefore be of major interest. Pigs represent a possible alternative source of beta cells. Grafting of pig islets may appear difficult because of the immunologic species barrier, but pig islets have been shown to function in primates for at least 6 mo with clinically incompatible immunosuppression. Therefore, a bioartificial pancreas made of encapsulated pig islets may resolve issues associated with islet allotransplantation. Although several groups have shown that encapsulated pig islets are functional in small-animal models, less is known about the use of bioartificial pancreases in large-animal models. In this review, we summarize current knowledge of encapsulated pig islets, to determine obstacles to implantation in humans and possible solutions to overcome these obstacles.
Collapse
|
25
|
Kerby A, Bohman S, Westberg H, Jones P, King A. Immunoisolation of islets in high guluronic acid barium-alginate microcapsules does not improve graft outcome at the subcutaneous site. Artif Organs 2012; 36:564-70. [PMID: 22372929 DOI: 10.1111/j.1525-1594.2011.01411.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The survival and function of alginate microencapsulated islets is suboptimal when transplanted to the intraperitoneal site of diabetic animals. The large capacity and convenience of the subcutaneous site make it an appropriate and attractive alternative for microencapsulated grafts. Nonencapsulated and high guluronic acid barium-alginate microencapsulated islets were transplanted to the intraperitoneal and subcutaneous sites of diabetic mice. Microencapsulation improved graft success up to 28 days at the intraperitoneal site but not at the subcutaneous site. Samples of microencapsulated islets transplanted into normoglycemic mice confirmed that insulin secretion, insulin content, and adenosine triphosphate content were reduced more significantly in subcutaneous graft islets than intraperitoneal graft islets after 7 days. In addition, a greater proportion of dead cells were observed in the subcutaneous graft islets than in intraperitoneal graft islets after 28 days. We conclude that using alginate microencapsulated islets transplanted to the unmodified subcutaneous site is insufficient to reverse the diabetic state. This finding is likely to be related to the inability of the site to support islet function and viability.
Collapse
Affiliation(s)
- Alan Kerby
- Diabetes Research Group, Division of Diabetes and Nutritional Sciences, King's College London, London, UK
| | | | | | | | | |
Collapse
|
26
|
Jahansouz C, Jahansouz C, Kumer SC, Brayman KL. Evolution of β-Cell Replacement Therapy in Diabetes Mellitus: Islet Cell Transplantation. J Transplant 2011; 2011:247959. [PMID: 22013505 PMCID: PMC3195999 DOI: 10.1155/2011/247959] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2011] [Accepted: 08/08/2011] [Indexed: 12/12/2022] Open
Abstract
Diabetes mellitus remains one of the leading causes of morbidity and mortality worldwide. According to the Centers for Disease Control and Prevention, approximately 23.6 million people in the United States are affected. Of these individuals, 5 to 10% have been diagnosed with Type 1 diabetes mellitus (T1DM), an autoimmune disease. Although it often appears in childhood, T1DM may manifest at any age, leading to significant morbidity and decreased quality of life. Since the 1960s, the surgical treatment for diabetes mellitus has evolved to become a viable alternative to insulin administration, beginning with pancreatic transplantation. While islet cell transplantation has emerged as another potential alternative, its role in the treatment of T1DM remains to be solidified as research continues to establish it as a truly viable alternative for achieving insulin independence. In this paper, the historical evolution, procurement, current status, benefits, risks, and ongoing research of islet cell transplantation are explored.
Collapse
Affiliation(s)
- Cyrus Jahansouz
- School of Medicine, University of Virginia, Charlottesville, VA 22102, USA
| | | | | | | |
Collapse
|
27
|
Vaithilingam V, Quayum N, Joglekar MV, Jensen J, Hardikar AA, Oberholzer J, Guillemin GJ, Tuch BE. Effect of alginate encapsulation on the cellular transcriptome of human islets. Biomaterials 2011; 32:8416-25. [PMID: 21889795 DOI: 10.1016/j.biomaterials.2011.06.044] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Accepted: 06/20/2011] [Indexed: 10/17/2022]
Abstract
Encapsulation of human islets may prevent their immune rejection when transplanted into diabetic recipients. To assist in understanding why clinical outcomes with encapsulated islets were not ideal, we examined the effect of encapsulation on their global gene (mRNA) and selected miRNAs (non-coding (nc)RNA) expression. For functional studies, encapsulated islets were transplanted into peritoneal cavity of diabetic NOD-SCID mice. Genomics analysis and transplantation studies demonstrate that islet origin and isolation centres are a major source of variation in islet quality. In contrast, tissue culture and the encapsulation process had only a minimal effect, and did not affect islet viability. Microarray analysis showed that as few as 29 genes were up-regulated and 2 genes down-regulated (cut-off threshold 0.1) by encapsulation. Ingenuity analysis showed that up-regulated genes were involved mostly in inflammation, especially chemotaxis, and vascularisation. However, protein expression of these factors was not altered by encapsulation, raising doubts about the biosignificance of the gene changes. Encapsulation had no effect on levels of islet miRNAs. In vivo studies indicate differences among the centres in the quality of the islets isolated. We conclude that microencapsulation of human islets with barium alginate has little effect on their transcriptome.
Collapse
|
28
|
Daoud J, Rosenberg L, Tabrizian M. Pancreatic Islet Culture and Preservation Strategies: Advances, Challenges, and Future Outlook. Cell Transplant 2010; 19:1523-35. [DOI: 10.3727/096368910x515872] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Postisolation islet survival is a critical step for achieving successful and efficient islet transplantation. This involves the optimization of islet culture in order to prolong survival and functionality in vitro. Many studies have focused on different strategies to culture pancreatic islets in vitro through manipulation of culture media, surface modified substrates, and the use of various techniques such as encapsulation, embedding, scaffold, and bioreactor culture strategies. This review aims to present and discuss the different methodologies employed to optimize pancreatic islet culture in vitro as well as address their respective advantages and drawbacks.
Collapse
Affiliation(s)
- Jamal Daoud
- Department of Biomedical Engineering, Faculty of Medicine, McGill University, Montreal, QC, Canada
| | - Lawrence Rosenberg
- Department of Surgery, Faculty of Medicine, McGill University, Montreal, QC, Canada
| | - Maryam Tabrizian
- Department of Biomedical Engineering, Faculty of Medicine, McGill University, Montreal, QC, Canada
| |
Collapse
|
29
|
Langlois G, Dusseault J, Bilodeau S, Tam SK, Magassouba D, Hallé JP. Direct effect of alginate purification on the survival of islets immobilized in alginate-based microcapsules. Acta Biomater 2009; 5:3433-40. [PMID: 19520193 DOI: 10.1016/j.actbio.2009.05.029] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Revised: 04/17/2009] [Accepted: 05/20/2009] [Indexed: 11/22/2022]
Abstract
Alginate purification has been shown to decrease the host immune response to implanted alginate-based microcapsules, but the direct effect of contaminants on islet cell survival remains unknown. Wistar rat islets were immobilized in calcium alginate beads made with crude vs. purified alginate and then incubated in CMRL culture medium. Islet survival was evaluated at 1, 4, 7, 14 and 27 days post-encapsulation. Islet viability was investigated using a dual staining assay (propidium iodide and orange acridine). The islet cell necrosis and the proportion of apoptotic cells were quantified under optical microscopy and with a TUNEL assay, respectively. Islets immobilized in purified alginate were more viable, and had fewer necrotic centers, a smaller area of central necrosis and a lower number of apoptotic cells. At day 14 and 27 post-encapsulation, respectively, 48% and 23% of islets were viable with purified alginate vs. 18% and 8% with crude alginate (p<0.05). At day 14, the surface area of central necrosis and the number of necrotic islets were more important with the impure alginate (65% vs. 45% and 73% vs. 53%, respectively; p<0.05). We conclude that alginate purification improves the survival of islets that are immobilized in alginate-based microcapsules. These findings indicate that caution should be taken in the interpretation of in vivo experiments, as the results could be explained by either a direct effect on islet survival or a modification of the host reaction, or both. Moreover, it suggests that the effect on islet viability should be assessed during the development of biomaterials for cell encapsulation.
Collapse
|
30
|
Abstract
In tissue engineering, innate responses to biomaterial scaffolds will affect rejection of allogeneic cells. Biomaterials directly influence innate and adaptive immune cell adhesion, reactive oxygen intermediate production, cytokine secretion, nuclear factor-kappa B nuclear translocation, gene expression, and cell surface markers, all of which are likely to affect allogeneic rejection responses. A major goal in tissue engineering is to induce transplant tolerance, potentially by manipulating the biomaterial component. This review describes methods of measuring responses of macrophages, dendritic cells, and T cells stimulated in vitro and in vivo and addresses key factors in assay development. Such tests include mixed leukocyte reactions, enzyme-linked immunosorbent spot assays, trans-vivo delayed-type hypersensitivity assays, and measurement of dendritic cell subsets and anti-donor antibodies; we propose extending these studies to tissue engineering.
Collapse
Affiliation(s)
- Kim S Jones
- Department of Chemical Engineering, McMaster University, Hamilton, Ontario, Canada.
| |
Collapse
|
31
|
Qi M, Strand BL, Mørch Y, Lacík I, Wang Y, Salehi P, Barbaro B, Gangemi A, Kuechle J, Romagnoli T, Hansen MA, Rodriguez LA, Benedetti E, Hunkeler D, Skjåk-Braek G, Oberholzer J. Encapsulation of human islets in novel inhomogeneous alginate-ca2+/ba2+ microbeads: in vitro and in vivo function. ACTA ACUST UNITED AC 2009; 36:403-20. [PMID: 18925451 DOI: 10.1080/10731190802369755] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Microencapsulation may allow for immunosuppression-free islet transplantation. Herein we investigated whether human islets can be shipped safely to a remote encapsulation core facility and maintain in vitro and in vivo functionality. In non-encapsulated islets before and encapsulated islets after shipment, viability was 88.3+/-2.5 and 87.5+/-2.7% (n=6, p=0.30). Stimulation index after static glucose incubation was 5.4+/-0.5 and 6.3+/-0.4 (n=6, p=0.18), respectively. After intraperitoneal transplantation, long-term normoglycemia was consistently achieved with 3,000, 5,000, and 10,000 IEQ encapsulated human islets. When transplanting 1,000 IEQ, mice returned to hyperglycemia after 30-55 (n=4/7) and 160 days (n=3/7). Transplanted mice showed human oral glucose tolerance with lower glucose levels than non-diabetic control mice. Capsules retrieved after transplantation were intact, with only minimal overgrowth. This study shows that human islets maintained the viability and in vitro function after encapsulation and the inhomogeneous alginate-Ca(2+)/Ba(2+) microbeads allow for long-term in vivo human islet graft function, despite long-distance shipment.
Collapse
Affiliation(s)
- Meirigeng Qi
- Department of Surgery, University of Illinois at Chicago, Illinois, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Mallett AG, Korbutt GS. Alginate Modification Improves Long-Term Survival and Function of Transplanted Encapsulated Islets. Tissue Eng Part A 2009; 15:1301-9. [DOI: 10.1089/ten.tea.2008.0118] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Aaron G. Mallett
- Alberta Diabetes Institute, University of Alberta, Edmonton, Canada
- Department of Surgery, University of Alberta, Edmonton, Canada
| | - Gregory S. Korbutt
- Alberta Diabetes Institute, University of Alberta, Edmonton, Canada
- Department of Surgery, University of Alberta, Edmonton, Canada
| |
Collapse
|
33
|
|
34
|
Koo SK, Kim SC, Wee YM, Kim YH, Jung EJ, Choi MY, Park YH, Park KT, Lim DG, Han DJ. Experimental microencapsulation of porcine and rat pancreatic islet cells with air-driven droplet generator and alginate. Transplant Proc 2008; 40:2578-80. [PMID: 18929806 DOI: 10.1016/j.transproceed.2008.08.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Transplantation of microencapsulated islets is proposed as an ideal therapy for the treatment of type 1 diabetes mellitus without immunosuppression. This strategy is based on the principle that foreign cells are protected from the host immune system by an artificial membrane. The aim of this study was to establish an ideal condition of microencapsulation using an air-driven droplet generator and alginate in vitro. The optimal conditions for islet encapsulation were an alginate inflow rate of 10 mL/h, CO2 flow rate of 2.0 L/min in a concentration of 2% alginate. For 2.5% alginate, the alginate inflow rate of 20 mL/h, CO2 flow rate 3.0 L/min was ideal; alginate inflow rate of 40 mL/h, CO2 flow rate of 4.0 L/min showed good microcapsules at 3% alginate. Viability of encapsulated islets was greater than 90%. In terms of insulin secretion, encapsulated islets secreted insulin in response to glucose in static culture medium. However, there was no normal response to low or high glucose challenge with a stimulation index less than 2.0. Microencapsulation of pig islets was successfully performed with air-driven droplet generator and alginate in vitro. Further studies about biocompatibility and glucose control in vivo may provide a useful tool for treatment of patients with diabetes mellitus.
Collapse
Affiliation(s)
- S K Koo
- Asan Institute for Life Science, Seoul, Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Emerich DF, Schneider P, Bintz B, Hudak J, Thanos CG. Aging reduces the neuroprotective capacity, VEGF secretion, and metabolic activity of rat choroid plexus epithelial cells. Cell Transplant 2008; 16:697-705. [PMID: 18019359 DOI: 10.3727/000000007783465145] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Delivery of neurotrophic molecules to the brain has potential for preventing neuronal loss in neurodegenerative disorders. Choroid plexus (CP) epithelial cells secrete numerous neurotrophic factors, and encapsulated CP transplants are neuroprotective in models of stroke and Huntington's disease (HD). To date, all studies examining the neuroprotective potential of CP transplants have used cells isolated from young donor animals. Because the aging process significantly impacts the cytoarchitecture and function of the CP the following studies determined whether age-related impairments occur in its neuroprotective capacity. CP was isolated from either young (3-4 months) or aged (24 months) rats. In vitro, young CP epithelial cells secreted more VEGF and were metabolically more active than aged CP epithelial cells. Additionally, conditioned medium from cultured aged CP was less potent than young CP at enhancing the survival of serum-deprived neurons. Finally, encapsulated CP was tested in an animal model of HD. Cell-loaded or empty alginate capsules (control group) were transplanted unilaterally into the rat striatum. Seven days later, the animals received an injection of quinolinic acid (QA; 225 nmol) adjacent to the implant site. Animals were tested for motor function 28 days later. In the control group, QA lesions severely impaired function of the contralateral forelimb. Implants of young CP were potently neuroprotective as rats receiving CP transplants were not significantly impaired when tested for motor function. In contrast, implants of CP from aged rats were only modestly effective and were much less potent than young CP transplants. These data are the first to directly link aging with diminished neuroprotective capacity of CP epithelial cells.
Collapse
|
36
|
Docherty K, Bernardo AS, Vallier L. Embryonic stem cell therapy for diabetes mellitus. Semin Cell Dev Biol 2007; 18:827-38. [DOI: 10.1016/j.semcdb.2007.09.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2007] [Accepted: 09/06/2007] [Indexed: 12/20/2022]
|
37
|
Gazda LS, Vinerean HV, Laramore MA, Diehl CH, Hall RD, Rubin AL, Smith BH. Encapsulation of porcine islets permits extended culture time and insulin independence in spontaneously diabetic BB rats. Cell Transplant 2007; 16:609-20. [PMID: 17912952 DOI: 10.3727/000000007783465028] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The ability to culture porcine islets for extended times allows for both their functional assessment and the assurance of their microbiological safety prior to transplantation. We have previously shown that agarose-encapsulated porcine islets can be cultured for at least 24 weeks. In the current study, porcine islet agarose macrobeads cultured for up to 67 weeks were assessed for their ability to restore normoglycemia, respond to an intraperitoneal glucose challenge, maintain spontaneously diabetic BB rats free of insulin therapy for more than 6 months, and for their biocompatibility. Porcine islets were encapsulated in agarose macrobeads and subjected to weekly static perifusion assays for the assessment of insulin production. After in vitro culture for either 9, 40, or 67 weeks, 56-60 macrobeads were transplanted to each spontaneously diabetic BB rat. Transplanted rats were monitored daily for blood glucose levels. Glucose tolerance tests and assessments for porcine C-peptide were conducted at various intervals throughout the study. Normoglycemia (100-200 mg/dl) was initially restored in all islet transplanted rats. Moderate hyperglycemia (200-400 mg/dl) developed at around 30 days posttransplantation and continued throughout the study period of 201-202 days. Importantly, all rats that received encapsulated porcine islets continued to gain weight and were free of exogenous insulin therapy for the entire study. Porcine C-peptide (0.2-0.9 ng/ml) was detected in the serum of islet recipients throughout the study period. No differences were detected between recipient animals receiving islet macrobeads of various ages. These results demonstrate that the encapsulation of porcine islets in agarose macrobeads allows for extended culture periods and is an appropriate strategy for functional and microbiological assessment prior to clinical use.
Collapse
|
38
|
Murua A, de Castro M, Orive G, Hernández RM, Pedraz JL. In Vitro Characterization and In Vivo Functionality of Erythropoietin-Secreting Cells Immobilized in Alginate−Poly-l-Lysine−Alginate Microcapsules. Biomacromolecules 2007; 8:3302-7. [DOI: 10.1021/bm070194b] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
39
|
Abstract
Diabetes is one of the most prevalent, costly, and debilitating diseases in the world. Although traditional insulin therapy has alleviated the short-term effects, long-term complications are ubiquitous and harmful. For these reasons, alternative treatment options are being developed. This review investigates one appealing area: cell replacement using encapsulated islets. Encapsulation materials, encapsulation methods, and cell sources are presented and discussed. In addition, the major factors that currently limit cell viability and functionality are reviewed, and strategies to overcome these limitations are examined. This review is designed to introduce the reader to cell replacement therapy and cell and tissue encapsulation, especially as it applies to diabetes.
Collapse
Affiliation(s)
- Jonathan Beck
- Department of Biological and Irrigation Engineering, Utah State University, Logan, Utah, USA
| | | | | | | | | | | |
Collapse
|
40
|
Abstract
Cellular therapies to treat Type 1 diabetes are being devised and the use of human embryonic stem cells (hESCs) offers a solution to the issue of supply, because hESCs can be maintained in a pluripotent state indefinitely. Furthermore, hESCs have advantages in terms of their plasticity and reduced immunogenicity. Several strategies that have so far been investigated indicate that hESCs are capable of differentiating into insulin producing beta-cell surrogates. However the efficiency of the differentiation procedures used is generally quite low and the cell populations derived are often highly heterogenous. A strategy that appears to have long term potential is to design differentiation procedures based on the ontogeny of the beta-cell. The focus of this strategy is to replicate signaling processes that are known to be involved in the maturation of a beta-cell. The earliest pancreatic progenitors found in the developing vertebrate fetus are produced via a process known as gastrulation and form part of the definitive endoderm germ layer. hESCs have recently been differentiated into definitive endoderm with high efficiency using a differentiation procedure that mimics the signaling that occurs during gastrulation and the formation of the definitive endoderm. Subsequent events during pancreas development involve a section of the definitive endoderm forming into pancreatic epithelium, which then branches into the pancreatic mesenchyme to form islet clusters of endocrine cells. A proportion of the endocrine precursor cells within islets develop into insulin producing beta-cells. The challenge currently is to design hESC differentiation procedures that mimic the combined events of these stages of beta-cell development.
Collapse
Affiliation(s)
- Justin G Lees
- Diabetes Transplant Unit, Prince of Wales Hospital/University of New South Wales, Randwick, New South Wales, Australia
| | | |
Collapse
|
41
|
Thanos CG, Bintz BE, Emerich DF. Stability of alginate-polyornithine microcapsules is profoundly dependent on the site of transplantation. J Biomed Mater Res A 2007; 81:1-11. [PMID: 17089418 DOI: 10.1002/jbm.a.31033] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Alginate encapsulation is a form of cell-based therapy with numerous preclinical successes but recalcitrant complications related to stability and reproducibility. Understanding how alginate stability varies across different transplant sites will help identify indications that might benefit most from this approach. Alginate stability has been quantified in the peritoneum, but there are no systematic studies comparing its relative stability across transplant sites. This study compares the stability of alginate-polycation microcapsules implanted in the peritoneum to those implanted in the brain and subcutaneous space at 14, 28, 60, 90, 120, and 180 days in-life. Using Fourier-Transform Infrared Spectroscopy (FTIR), the surface of explanted capsules was analyzed for the relative proportion of alginate (outer coat) and the polycationic polyornithine (middle coat). Using a mathematic relationship between FTIR peaks related to these two material components, an index was generated to compare the stability of four different alginates. A notable difference was observed with rapid breakdown in the peritoneum. Conversely, identical alginate capsules transplanted into the brain or subcutaneous space were stable for the 6 month study. These data suggest that (1) successful intraperitoneal transplantation requires modifications of the capsule configuration, the host environment, or both and (2) that sites such as the brain and subcutaneous space are inherently less hostile to conventional alginate capsule configurations.
Collapse
Affiliation(s)
- C G Thanos
- LCT BioPharma, Incorporated, Providence, RI 02906, USA.
| | | | | |
Collapse
|
42
|
Bohman S, Andersson A, King A. No differences in efficacy between noncultured and cultured islets in reducing hyperglycemia in a nonvascularized islet graft model. Diabetes Technol Ther 2006; 8:536-45. [PMID: 17037968 DOI: 10.1089/dia.2006.8.536] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Although islet transplantation is a promising method to restore normoglycemia in recipients with diabetes, large numbers of pancreatic islets are still needed. It has been suggested that the use of freshly isolated islets could improve transplantation outcome through better vascular engraftment. Using a technique of microencapsulation, a model where revascularization is not possible, we investigated the importance of revascularization for transplantation outcome. METHODS Either 700 or 350 3-day-cultured or noncultured encapsulated islets were transplanted intraperitoneally into syngeneic mice with alloxan-induced diabetes. In addition, 700 nonencapsulated islets were transplanted to mice with diabetes. Blood glucose concentrations were monitored, and glucose tolerance tests were carried out. After 42 days, the encapsulated islets were retrieved and assayed for glucose oxidation and insulin release rates. RESULTS There were no differences between capsules containing fresh or cultured islets in their capacity to lower the blood glucose concentration of the recipients or in the in vitro function after capsule retrieval. Interestingly, mice that were intraperitoneally transplanted with 700 encapsulated islets had average blood glucose levels well below 11 mM for most of the study, whereas the same number of nonencapsulated islets had no beneficial effects on the blood glucose homeostasis. CONCLUSIONS Encapsulated islets can reverse hyperglycemia after transplantation to the intraperitoneal site. This effect was not seen when nonencapsulated islets were grafted. Since a 3- day culture period did not influence the outcome of transplantation of encapsulated islets there is evidence to suggest that a more appropriate revascularization may explain why freshly isolated islets are more efficient than cultured islets.
Collapse
Affiliation(s)
- Sara Bohman
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden.
| | | | | |
Collapse
|
43
|
Emerich DF, Thanos CG, Goddard M, Skinner SJM, Geany MS, Bell WJ, Bintz B, Schneider P, Chu Y, Babu RS, Borlongan CV, Boekelheide K, Hall S, Bryant B, Kordower JH. Extensive neuroprotection by choroid plexus transplants in excitotoxin lesioned monkeys. Neurobiol Dis 2006; 23:471-80. [PMID: 16777422 DOI: 10.1016/j.nbd.2006.04.014] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Revised: 04/04/2006] [Accepted: 04/07/2006] [Indexed: 11/20/2022] Open
Abstract
Huntington's disease (HD) results from degeneration of striatal neurons. Choroid plexus (CP) cells secrete neurotrophic factors, and CP transplants are neuroprotective in rat models of HD. To determine if similar neuroprotective effects could be obtained in primates, porcine CP was encapsulated in alginate capsules. PCR confirmed that the CP cells expressed transthyretin and immunocytochemistry demonstrated typical ZO-1 and tubulin staining. In vitro, CP conditioned media enhanced the survival and preserved neurite number and length on serum deprived neurons. Cynomolgus primates were transplanted with CP-loaded capsules into the caudate and putamen followed by quinolinic acid (QA) lesions 1 week later. Control monkeys received empty capsules plus QA. Choroid plexus transplants significantly protected striatal neurons as revealed by stereological counts of NeuN-positive neurons (8% loss vs. 43% in controls) and striatum volume (10% decrease vs. 40% in controls). These data indicate that CP transplants might be useful for preventing the degeneration of neurons in HD.
Collapse
|
44
|
Dufrane D, Goebbels RM, Saliez A, Guiot Y, Gianello P. Six-month survival of microencapsulated pig islets and alginate biocompatibility in primates: proof of concept. Transplantation 2006; 81:1345-53. [PMID: 16699465 DOI: 10.1097/01.tp.0000208610.75997.20] [Citation(s) in RCA: 147] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Pig islets xenotransplantation remains associated with a strong humoral and cellular xenogeneic immune responses. The aim of this study was to assess the long-term biocompatibility of alginate encapsulated pig islets after transplantation in primates. METHODS Adult pig islets encapsulated in alginate under optimal conditions (n=7) or not (n=5) were transplanted under the kidney capsule of nondiabetic Cynomolgus maccacus. Additional primates received empty capsules (n=1) and nonencapsulated pig islets (n=2) as controls. Capsule integrity, cellular overgrowth, pig islet survival, porcine C-peptide and anti-pig IgM/IgG antibodies were examined up to 6 months after implantation. RESULTS Nonencapsulated islets and islets encapsulated in nonoptimal capsules were rapidly destroyed. In seven primates receiving perfectly encapsulated pig islets, part of the islets survived up to 6 months after implantation without immunosuppression. Porcine C-peptide was detected after 1 month in 71% of the animals. The majority of grafts (86%) were intact and completely free of cellular overgrowth or capsule fibrosis. Explanted capsules, after 135 (n=2/2) and 180 (n=2/3) days, demonstrated residual insulin content and responses to glucose challenge (stimulation index of 2.2). Partial islet survival was obtained despite an elicited anti-pig IgG humoral response. CONCLUSIONS Optimal alginate encapsulation significantly prolonged adult pig islet survival into primates for up to 6 months, even in the presence of antibody response.
Collapse
Affiliation(s)
- Denis Dufrane
- Laboratory of Experimental Surgery, Université catholique de Louvain, Faculté de Médecine, and Department of Pathology, Cliniques Universitaires Saint-Luc, Brussels, Belgium
| | | | | | | | | |
Collapse
|
45
|
Kobayashi T, Harb G, Rayat GR. Prolonged Survival of Microencapsulated Neonatal Porcine Islets in Mice Treated with a Combination of Anti-CD154 and Anti-LFA-1 Monoclonal Antibodies. Transplantation 2005; 80:821-7. [PMID: 16210971 DOI: 10.1097/01.tp.0000173773.01811.88] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND The aim of this study was to determine whether short-term administration of a combination of anti-CD154 and anti-LFA-1 monoclonal antibodies can prolong the survival of microencapsulated neonatal porcine islets (NPI) in immunocompetent mice. METHODS Microencapsulated NPI were transplanted into the peritoneal cavity of streptozotocin-induced diabetic B6 mice that received a short-term treatment of a combination of anti-CD154 and anti-LFA-1 monoclonal antibodies. Blood glucose levels of each recipient were measured for more than 100 days posttransplantation or until graft rejection. Microcapsules were recovered to determine the presence of immune cells using immunoperoxidase staining. In addition, the levels of mouse anti-porcine immunoglobulin (Ig) G antibodies in the serum of each recipient were measured by flow cytometry. RESULTS Short-term administration of a combination of monoclonal antibodies resulted in significant prolongation of microencapsulated NPI xenograft survival. All treated mice (n = 20) achieved normoglycemia within 10-35 days posttransplantation and 11/20 mice remained normoglycemic for more than 100 days posttransplantation. In contrast, only 1/20 of the untreated mice achieved normoglycemia and this mouse became diabetic at 17 days posttransplantation. Histological examination of the recovered microcapsules from long-term surviving treated mice revealed minimal cellular overgrowth containing intact viable islets, whereas several layers of immune cells surrounding the capsules containing nonviable islets were observed in untreated mice. The levels of mouse anti-porcine IgG was also reduced in treated recipients compared to untreated mice. CONCLUSIONS These data demonstrate that short-term administration of anti-CD154 and anti-LFA-1 monoclonal antibodies can be effective in promoting long-term survival of microencapsulated NPI in immune-competent mice.
Collapse
Affiliation(s)
- Tsunehiro Kobayashi
- Surgical-Medical Research Institute, Department of Surgery, University of Alberta, Edmonton, Alberta, Canada
| | | | | |
Collapse
|
46
|
|
47
|
|