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Lehnert S, Sikorski P. Application of Temporary, Cell-Containing Alginate Microcarriers to Facilitate the Fabrication of Spatially Defined Cell Pockets in 3D Collagen Hydrogels. Macromol Biosci 2021; 22:e2100319. [PMID: 34679232 DOI: 10.1002/mabi.202100319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 09/29/2021] [Indexed: 11/08/2022]
Abstract
Mimicking the complexity of natural tissue is a major challenge in the field of tissue engineering. Here, a facile 2-step fabrication method to prepare 3D constructs with distinct regions of high cell concentrations and without the need for elaborate equipment is proposed. The initial incorporation of cells in a sacrificial alginate matrix allows the addition of other, cell relevant biopolymers, such as, collagen to form a spatially confined, interpenetrating network at the microscale. A layered structure at the macroscale can be achieved by incorporating these cell-containing microspheres in thin collagen layers. Cells are locally released by de-gelling the alginate matrix and their attachment to the collagen hydrogel layers has been studied. The use of the murine pre-osteoblast cell line MC3T3-E1 as an example cell line shows that the cells behave differently in their cell migration pattern based on the initial composition of the alginate microspheres.
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Affiliation(s)
- Sarah Lehnert
- Department of Physics, Norwegian University of Science and Technology (NTNU), Høgskoleringen 5, Trondheim, 7034, Norway
| | - Pawel Sikorski
- Department of Physics, Norwegian University of Science and Technology (NTNU), Høgskoleringen 5, Trondheim, 7034, Norway
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Lin D, Chen X, Liu Y, Lin Z, Luo Y, Fu M, Yang N, Liu D, Cao J. Microgel Single-Cell Culture Arrays on a Microfluidic Chip for Selective Expansion and Recovery of Colorectal Cancer Stem Cells. Anal Chem 2021; 93:12628-12638. [PMID: 34495647 DOI: 10.1021/acs.analchem.1c02335] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cancer stem cells (CSCs) are rare and lack definite biomarkers, necessitating new methods for a robust expansion. Here, we developed a microfluidic single-cell culture (SCC) approach for expanding and recovering colorectal CSCs from both cell lines and tumor tissues. By incorporating alginate hydrogels with droplet microfluidics, a high-density microgel array can be formed on a microfluidic chip that allows for single-cell encapsulation and nonadhesive culture. The SCC approach takes advantage of the self-renewal property of stem cells, as only the CSCs can survive in the SCC and form tumorspheres. Consecutive imaging confirmed the formation of single-cell-derived tumorspheres, mainly from a population of small-sized cells. Through on-chip decapsulation of the alginate microgel, ∼6000 live cells can be recovered in a single run, which is sufficient for most biological assays. The recovered cells were verified to have the genetic and phenotypic characteristics of CSCs. Furthermore, multiple CSC-specific targets were identified by comparing the transcriptomics of the CSCs with the primary cancer cells. To summarize, the microgel SCC array offers a label-free approach to obtain sufficient quantities of CSCs and thus is potentially useful for understanding cancer biology and developing personalized CSC-targeting therapies.
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Affiliation(s)
- Dongguo Lin
- School of Medicine, South China University of Technology, Guangzhou 510006, China.,Department of Laboratory Medicine, Guangzhou First People's Hospital, South China University of Technology, Guangzhou 510180, China.,Guangdong Engineering Technology Research Center of Microfluidic Chip Medical Diagnosis, Guangzhou 510180, China
| | - Xiao Chen
- School of Medicine, South China University of Technology, Guangzhou 510006, China
| | - Yang Liu
- School of Medicine, South China University of Technology, Guangzhou 510006, China
| | - Zhun Lin
- School of Medicine, South China University of Technology, Guangzhou 510006, China
| | - Yanzhang Luo
- Department of Laboratory Medicine, Guangzhou First People's Hospital, South China University of Technology, Guangzhou 510180, China
| | - Mingpeng Fu
- Department of Laboratory Medicine, Guangzhou First People's Hospital, South China University of Technology, Guangzhou 510180, China
| | - Na Yang
- Department of Laboratory Medicine, Guangzhou First People's Hospital, South China University of Technology, Guangzhou 510180, China
| | - Dayu Liu
- School of Medicine, South China University of Technology, Guangzhou 510006, China.,Department of Laboratory Medicine, Guangzhou First People's Hospital, South China University of Technology, Guangzhou 510180, China.,Guangdong Engineering Technology Research Center of Microfluidic Chip Medical Diagnosis, Guangzhou 510180, China
| | - Jie Cao
- School of Medicine, South China University of Technology, Guangzhou 510006, China.,Department of General Surgery, The Second Affiliated Hospital of South China University of Technology, 1, Panfu Road, Guangzhou 510180, China
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Mooranian A, Jones M, Ionescu CM, Walker D, Wagle SR, Kovacevic B, Chester J, Foster T, Johnston E, Mikov M, Al-Salami H. Advancements in Assessments of Bio-Tissue Engineering and Viable Cell Delivery Matrices Using Bile Acid-Based Pharmacological Biotechnologies. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:1861. [PMID: 34361247 PMCID: PMC8308343 DOI: 10.3390/nano11071861] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 07/07/2021] [Accepted: 07/14/2021] [Indexed: 12/18/2022]
Abstract
The utilisation of bioartificial organs is of significant interest to many due to their versatility in treating a wide range of disorders. Microencapsulation has a potentially significant role in such organs. In order to utilise microcapsules, accurate characterisation and analysis is required to assess their properties and suitability. Bioartificial organs or transplantable microdevices must also account for immunogenic considerations, which will be discussed in detail. One of the most characterized cases is the investigation into a bioartificial pancreas, including using microencapsulation of islets or other cells, and will be the focus subject of this review. Overall, this review will discuss the traditional and modern technologies which are necessary for the characterisation of properties for transplantable microdevices or organs, summarizing analysis of the microcapsule itself, cells and finally a working organ. Furthermore, immunogenic considerations of such organs are another important aspect which is addressed within this review. The various techniques, methodologies, advantages, and disadvantages will all be discussed. Hence, the purpose of this review is providing an updated examination of all processes for the analysis of a working, biocompatible artificial organ.
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Affiliation(s)
- Armin Mooranian
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (M.J.); (C.M.I.); (D.W.); (S.R.W.); (B.K.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia
| | - Melissa Jones
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (M.J.); (C.M.I.); (D.W.); (S.R.W.); (B.K.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia
| | - Corina Mihaela Ionescu
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (M.J.); (C.M.I.); (D.W.); (S.R.W.); (B.K.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia
| | - Daniel Walker
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (M.J.); (C.M.I.); (D.W.); (S.R.W.); (B.K.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia
| | - Susbin Raj Wagle
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (M.J.); (C.M.I.); (D.W.); (S.R.W.); (B.K.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia
| | - Bozica Kovacevic
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (M.J.); (C.M.I.); (D.W.); (S.R.W.); (B.K.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia
| | - Jacqueline Chester
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (M.J.); (C.M.I.); (D.W.); (S.R.W.); (B.K.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia
| | - Thomas Foster
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (M.J.); (C.M.I.); (D.W.); (S.R.W.); (B.K.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia
| | - Edan Johnston
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (M.J.); (C.M.I.); (D.W.); (S.R.W.); (B.K.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia
| | - Momir Mikov
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Hajduk Veljkova 3, 21101 Novi Sad, Serbia;
| | - Hani Al-Salami
- The Biotechnology and Drug Development Research Laboratory, Curtin Medical School, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, WA 6102, Australia; (A.M.); (M.J.); (C.M.I.); (D.W.); (S.R.W.); (B.K.); (J.C.); (T.F.); (E.J.)
- Hearing Therapeutics, Ear Science Institute Australia, Queen Elizabeth II Medical Centre, Nedlands, Perth, WA 6009, Australia
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de Groot M, Schuurs TA, Keizer PPM, Fekken S, Leuvenink HGD, Van Schilfgaarde R. Response of Encapsulated Rat Pancreatic Islets to Hypoxia. Cell Transplant 2017; 12:867-875. [PMID: 28863739 DOI: 10.3727/000000003771000219] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Hypoxia contributes to encapsulated pancreatic islet graft failure. To gain insight into the mechanisms that lead to hypoxia-induced graft failure, encapsulated islet function, vitality, and cell replication were assessed after 2 and 5 days of hypoxic (1% O2) and normoxic (20% O2) culture. The mRNA expression levels of Bcl-2, Bax, inducible nitric oxide synthase (iNOS), and monocyte chemoattractant protein 1 (MCP-1) were assessed, as well as the amount of nitrite and MCP-1 in the culture medium. Hypoxia was associated with loss of encapsulated islet function and vitality, but not with an increase in islet cell replication. Loss of vitality was due to necrosis, and only modestly due to apoptosis. Hypoxia was not associated with changes in the Bcl-2/Bax mRNA ratio, but it did increase the expression of iNOS and MCP-1 mRNA. The increased mRNA levels were, however, not associated with elevated concentrations of nitrite nor with elevated levels of MCP-1 protein. The increased iNOS mRNA levels imply a role for NO in the completion of cell death by hypoxia. The increased MCP-1 mRNA levels suggest that encapsulated islets in vivo contribute to their own graft failure by attracting cytokine-producing macrophages. The discrepancy between iNOS mRNA and nitrite is explained by the longer half-life of NO during hypoxia. MCP-1 protein levels are underestimated as a consequence of the lower number of vital cells in combination with a higher proteolytic activity due to necrosis. Thus, strategies to eliminate hypoxia may not only improve islet function and vitality, but may also reduce the attraction of macrophages by encapsulated islets.
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Affiliation(s)
- M de Groot
- Surgical Research Laboratory, Department of Surgery, Groningen University Hospital, Groningen, The Netherlands
| | - T A Schuurs
- Surgical Research Laboratory, Department of Surgery, Groningen University Hospital, Groningen, The Netherlands
| | - P P M Keizer
- Surgical Research Laboratory, Department of Surgery, Groningen University Hospital, Groningen, The Netherlands
| | - S Fekken
- Surgical Research Laboratory, Department of Surgery, Groningen University Hospital, Groningen, The Netherlands
| | - H G D Leuvenink
- Surgical Research Laboratory, Department of Surgery, Groningen University Hospital, Groningen, The Netherlands
| | - R Van Schilfgaarde
- Surgical Research Laboratory, Department of Surgery, Groningen University Hospital, Groningen, The Netherlands
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Jérôme V, Werner M, Kaiser P, Freitag R. Creating a Biomimetic Microenvironment for the Ex Vivo Expansion of Primary Human T Lymphocytes. Macromol Biosci 2017; 17. [DOI: 10.1002/mabi.201700091] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 04/27/2017] [Indexed: 01/17/2023]
Affiliation(s)
- Valérie Jérôme
- Process Biotechnology; University of Bayreuth; D-95447 Bayreuth Germany
| | - Melanie Werner
- Process Biotechnology; University of Bayreuth; D-95447 Bayreuth Germany
| | - Patrick Kaiser
- Process Biotechnology; University of Bayreuth; D-95447 Bayreuth Germany
| | - Ruth Freitag
- Process Biotechnology; University of Bayreuth; D-95447 Bayreuth Germany
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6
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Werner M, Schmoldt D, Hilbrig F, Jérôme V, Raup A, Zambrano K, Hübner H, Buchholz R, Freitag R. High cell density cultivation of human leukemia T cells (Jurkat cells) in semipermeable polyelectrolyte microcapsules. Eng Life Sci 2015. [DOI: 10.1002/elsc.201400186] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Affiliation(s)
- Melanie Werner
- Chair for Process BiotechnologyUniversität Bayreuth, Bayreuth Germany
| | - Daria Schmoldt
- Chair for Process BiotechnologyUniversität Bayreuth, Bayreuth Germany
| | - Frank Hilbrig
- Chair for Process BiotechnologyUniversität Bayreuth, Bayreuth Germany
| | - Valérie Jérôme
- Chair for Process BiotechnologyUniversität Bayreuth, Bayreuth Germany
| | - Alexander Raup
- Institute of Bioprocess EngineeringFriedrich‐Alexander‐Universität Erlangen‐Nürnberg, Erlangen Germany
| | - Kenny Zambrano
- Institute of Bioprocess EngineeringFriedrich‐Alexander‐Universität Erlangen‐Nürnberg, Erlangen Germany
| | - Holger Hübner
- Institute of Bioprocess EngineeringFriedrich‐Alexander‐Universität Erlangen‐Nürnberg, Erlangen Germany
| | - Rainer Buchholz
- Institute of Bioprocess EngineeringFriedrich‐Alexander‐Universität Erlangen‐Nürnberg, Erlangen Germany
| | - Ruth Freitag
- Chair for Process BiotechnologyUniversität Bayreuth, Bayreuth Germany
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Vollert I, Seiffert M, Bachmair J, Sander M, Eder A, Conradi L, Vogelsang A, Schulze T, Uebeler J, Holnthoner W, Redl H, Reichenspurner H, Hansen A, Eschenhagen T. In vitro perfusion of engineered heart tissue through endothelialized channels. Tissue Eng Part A 2013; 20:854-63. [PMID: 24156346 DOI: 10.1089/ten.tea.2013.0214] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
In engineered heart tissues (EHT), oxygen and nutrient supply via mere diffusion is a likely factor limiting the thickness of cardiac muscle strands. Here, we report on a novel method to in vitro perfuse EHT through tubular channels. Adapting our previously published protocols, we expanded a miniaturized fibrin-based EHT-format to a larger six-well format with six flexible silicone posts holding each EHT (15×25×3 mm³). Thin dry alginate fibers (17×0.04×0.04 mm) were embedded into the cell-fibrin-thrombin mix and, after fibrin polymerization, dissolved by incubation in alginate lyase or sodium citrate. Oxygen concentrations were measured with a microsensor in 14-day-old EHTs (37°C, 21% oxygen) and ranged between 9% at the edges and 2% in the center of the tissue. Perfusion rapidly increased it to 10%-12% in the immediate vicinity of the microchannel. Continuous perfusion (20 μL/h, for 3 weeks) of the tubular lumina (100-500 μm) via hollow posts of the silicone rack increased mean dystrophin-positive cardiomyocyte density (36%±6% vs. 10%±3% of total cell number) and cross sectional area (73±2 vs. 48±1 μm²) in the central part of the tissue compared to nonperfused EHTs. The channels were populated by endothelial cells present in the reconstitution cell mix. In conclusion, we developed a novel approach to generate small tubular structures suitable for perfusion of spontaneously contracting and force-generating EHTs and showed that prolonged perfusion improved cardiac tissue structure.
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Affiliation(s)
- Ingra Vollert
- 1 Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf , Hamburg, Germany
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Werner M, Biss K, Jérôme V, Hilbrig F, Freitag R, Zambrano K, Hübner H, Buchholz R, Mahou R, Wandrey C. Use of the mitochondria toxicity assay for quantifying the viable cell density of microencapsulated jurkat cells. Biotechnol Prog 2013; 29:986-93. [PMID: 23636962 DOI: 10.1002/btpr.1734] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 02/28/2013] [Indexed: 01/19/2023]
Abstract
The mitochondria toxicity assay (MTT assay) is an established method for monitoring cell viability based on mitochondrial activity. Here the MTT assay is proposed for the in situ quantification of the living cell density of microencapsulated Jurkat cells. Three systems were used to encapsulate the cells, namely a membrane consisting of an interpenetrating polyelectrolyte network of sodium cellulose sulphate/poly(diallyldimethylammonium chloride) (NaCS/PDADMAC), a calcium alginate hydrogel covered with poly(L-lysine) (Ca-alg-PLL), and a novel calcium alginate-poly(ethylene glycol) hybrid material (Ca-alg-PEG). MTT results were correlated to data obtained by the trypan blue exclusion assay after release of the cells from the NaCS/PDADMAC and Ca-alg-PLL capsules, while a resazurin-based assay was used for comparison in case of the Ca-alg-PEG material. Analysis by MTT assay allows quick and reliable determination of viable cell densities of encapsulated cells independent of the capsule material. The assay is highly reproducible with inter-assay relative standard deviations below 10%.
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Affiliation(s)
- M Werner
- Chair for Process Biotechnology, University of Bayreuth, Bayreuth, Germany
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Safety and efficacy of ethylenediaminetetraacetic acid for removing microcapsules. J Surg Res 2013; 183:442-9. [PMID: 23453836 DOI: 10.1016/j.jss.2013.01.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 01/08/2013] [Accepted: 01/11/2013] [Indexed: 11/22/2022]
Abstract
BACKGROUND Microencapsulated islets are used to prevent immune rejection associated with pancreatic islet transplantation, but cellular overgrowth affects transplantation success, necessitating removal of microcapsules prior to retransplantation. This study aimed to investigate the safety and efficacy of ethylendiaminetetraacetic acid (EDTA) for the removal of microcapsules surrounding islet cells. METHODS Microcapsule dissolution was investigated after in vitro exposure to EDTA for 72 h. Dissolution, blood biochemical markers, and pathologic changes in abdominal organs were observed after intraperitoneal administration of different concentrations of EDTA to rats with abdominally transplanted empty microcapsules. The extent of overgrowth and time to adhesion development were recorded after implantation of microencapsulated islets into the abdominal cavity of diabetic rats. EDTA (0-240 mmol/L) was injected to observe the transplantation effect and ability to dissolve microcapsules. RESULTS There was a positive correlation between the rate of microcapsule dissolution and EDTA concentration in vitro. Following administration of 60 mmol/L EDTA, the majority of microcapsules within the abdominal cavity were dissolved and the retrieval rate was 2.6%. No adverse effects, abnormal blood biochemical markers, or organ damage were observed in rats 1 mo following intraperitoneal injection with EDTA at doses up to 60 mmol/L. Microcapsule retrieval and blood glucose were significantly higher in cases of grade II cellular overgrowth than in cases of grade 0-I overgrowth. CONCLUSIONS EDTA (60 mmol/L) dissolved microcapsules in vivo without affecting islet cell viability or secretion capacity, and without affecting blood biochemical markers. Optimal dissolution was achieved with grade 0-I overgrowth after implantation of microencapsulated islets.
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Thakur A, Sengupta R, Matsui H, Lillicrap D, Jones K, Hortelano G. Characterization of viability and proliferation of alginate-poly-L-lysine-alginate encapsulated myoblasts using flow cytometry. J Biomed Mater Res B Appl Biomater 2010; 94:296-304. [PMID: 20586078 DOI: 10.1002/jbm.b.31648] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Genetically modified cells encapsulated in alginate-poly-L-lysine-alginate (APA) are being developed to deliver therapeutic products to treat a variety of diseases. The characterization of the encapsulated cells thus becomes paramount. This study reports a novel method to assess the viability, granularity and proliferation of encapsulated cells based on flow cytometry. The in vitro viability of encapsulated G8 murine myoblasts secreting canine FVIII (cFVIII) measured by flow cytometry was comparable to the traditional trypan blue exclusion method and both correlated with cFVIII secretion levels. In contrast, after implantation into mice, only viability measured by flow cytometry correlated with cFVIII secretion. Further, flow cytometry analysis of encapsulated cells maintained in vitro and in vivo revealed a greater fraction of granular cells compared to free cells, suggesting that encapsulation influences the morphology (cytoplasmic composition) of cells within APA microcapsules. Interestingly, the proliferation study showed that encapsulated cells proliferate faster, on average, and were more heterogeneous in vivo compared to in vitro culture conditions, suggesting that encapsulated cell proliferation is complex and environment-dependent. In conclusion, we show that flow cytometry analysis allows for a more consistent and comprehensive examination of encapsulated cells to aid in the development of cell therapy protocols.
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Affiliation(s)
- Ajit Thakur
- School of Biomedical Engineering, McMaster University, Hamilton L8N3Z5, Ontario, Canada
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Jing D, Parikh A, Tzanakakis ES. Cardiac cell generation from encapsulated embryonic stem cells in static and scalable culture systems. Cell Transplant 2010; 19:1397-412. [PMID: 20587137 DOI: 10.3727/096368910x513955] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Heart diseases are major causes of morbidity and mortality linked to extensive loss of cardiac cells. Embryonic stem cells (ESCs) give rise to cardiomyocyte-like cells, which may be used in heart cell replacement therapies. Most cardiogenic differentiation protocols involve the culture of ESCs as embryoid bodies (EBs). Stirred-suspension bioreactor cultures of ESC aggregates may be employed for scaling up the production of cardiomyocyte progeny but the wide range of EB sizes and the unknown effects of the hydrodynamic environment on differentiating EBs are some of the major challenges in tightly controlling the differentiation outcome. Here, we explored the cardiogenic potential of mouse ESCs (mESCs) and human ESCs (hESCs) encapsulated in poly-L-lysine (pLL)-coated alginate capsules. Liquefaction of the capsule core led to the formation of single ESC aggregates within each bead and their average size depended on the concentration of seeded ESCs. Encapsulated mESCs were directed along cardiomyogenic lineages in dishes under serum-free conditions with the addition of bone morphogenetic protein 4 (BMP4). Human ESCs in pLL-layered liquid core (LC) alginate beads were also differentiated towards heart cells in serum-containing media. Besides the robust cell proliferation, higher fractions of cells expressing cardiac markers were detected in ESCs encapsulated in LC than in solid beads. Furthermore, we demonstrated for the first time that ESCs encapsulated in pLL-layered LC alginate beads can be coaxed towards heart cells in stirred-suspension bioreactors. Encapsulated ESCs yielded higher fractions of Nkx2.5- and GATA4-positive cells in the bioreactor compared to dish cultures. Differentiated cells formed beating foci that responded to chronotropic agents in an organotypic manner. Our findings warrant further development and implementation of microencapsulation technologies in conjunction with bioreactor cultivation to enable the production of stem cell-derived cardiac cells appropriate for clinical therapies and applications.
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Affiliation(s)
- Donghui Jing
- Department of Chemical and Biological Engineering, State University of New York at Buffalo, Buffalo, NY 14260, USA
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12
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Lv G, Sun Z, Li S, Yu W, Xie Y, Zhang Y, Xie H, Li X, Wang W, Ma X. Permeability changes of the cell-contained microcapsules visualized by confocal laser scanning microscope. J Biomed Mater Res A 2009; 90:773-83. [DOI: 10.1002/jbm.a.32115] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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13
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de Groot M, Schuurs TA, van Schilfgaarde R. Causes of limited survival of microencapsulated pancreatic islet grafts. J Surg Res 2004; 121:141-50. [PMID: 15313388 DOI: 10.1016/j.jss.2004.02.018] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2003] [Indexed: 01/02/2023]
Abstract
Successful transplantation of pancreatic tissue has been demonstrated to be an efficacious method of restoring glycemic control in type 1 diabetic patients. To establish graft acceptance patients require lifelong immunosuppression, which in turn is associated with severe deleterious side effects. Microencapsulation is a technique that enables the transplantation of pancreatic islets in the absence of immunosuppression by protecting the islet tissue through a mechanical barrier. This protection may even allow for the transplantation of animal tissue, which opens the perspective of using animal donors as a means to solve the problem of organ shortage. Microencapsulation is not yet applied in clinical practice, mainly because encapsulated islet graft survival is limited. In the present review we discuss the principal causes of microencapsulated islet graft failure, which are related to a lack of biocompatibility, limited immunoprotective properties, and hypoxia. Next to the causes of encapsulated islet graft failure we discuss possible improvements in the encapsulation technique and additional methods that could prolong encapsulated islet graft survival. Strategies that may well support encapsulated islet grafts include co-encapsulation of islets with Sertoli cells, the genetic modification of islet cells, the creation of an artificial implantation site, and the use of alternative donor sources. We conclude that encapsulation in combination with one or more of these additional strategies may well lead to a simple and safe transplantation therapy as a cure for diabetes.
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Affiliation(s)
- Martijn de Groot
- Surgical Research Laboratory, Department of Surgery, University Hospital Groningen, Hanzeplein 1 (CMC V, Y2144), 9713 GZ Groningen, Netherlands.
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