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Manipulation of Human Primary Endothelial Cell and Osteoblast Coculture Ratios to Augment Vasculogenesis and Mineralization. Ann Plast Surg 2017; 77:122-8. [PMID: 25144419 DOI: 10.1097/sap.0000000000000318] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Tissue-engineering scaffolds are often seeded with a single type of cell, but there has been more focus on cocultures to improve angiogenesis and bone formation for craniofacial applications. Investigation of bone-derived osteoblasts (OBs) is important because of the use of bone grafts and migration of OBs from native bone into constructs in vivo and therefore, their contribution to bone formation in vivo. The limitation of primary OBs has been their inability to mineralize without osteogenic factors in vitro. Through coculture of OBs and endothelial cells (ECs) and manipulation of the coculture ratio, mineralization can be achieved without osteogenic media or additional growth factors, thus enhancing their utility for tissue-engineering applications. An optimal ratio of EC/OB for vasculogenesis and mineralization has not been determined for human primary cells. Human umbilical vein ECs were cultured with normal human primary OBs in different EC/OB ratios, namely, 10:1, 5:1, 1:1, 1:5, and 1:10 with EC and OB monocultures as controls. The number of vasculogenic networks in a collagen matrix was highest in ratios of 5:1 and 1:1. ECs lined up and formed capillary-like networks by day 10, which was not seen in the other groups. On polystyrene, cells were cocultured with ECs and OBs in direct contact (direct coculture) or separated by a transwell membrane (indirect coculture). At day 21, Alizarin Red staining showed mineralization on the 1:5 and 1:10 direct coculture ratios, with 1:5 having more mineralization nodules present than 1:10. No mineralization was seen in other direct coculture ratios or in any of the indirect coculture ratios. Alkaline phosphatase secretion was highest in the 1:5 direct coculture group. Vascular endothelial growth factor secretion from OBs was present in the 1:5 and 1:10 direct coculture ratios at all time points and inhibited after day 1 in other coculture groups. To improve vasculogenesis, cocultures of primary human ECs and OBs in ratios of 5:1 should be used, but to improve bone formation, the 1:5 direct coculture ratio results in most mineralization.
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Hogrebe NJ, Reinhardt JW, Gooch KJ. Biomaterial microarchitecture: a potent regulator of individual cell behavior and multicellular organization. J Biomed Mater Res A 2016; 105:640-661. [DOI: 10.1002/jbm.a.35914] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Revised: 08/17/2016] [Accepted: 09/02/2016] [Indexed: 11/12/2022]
Affiliation(s)
- Nathaniel J. Hogrebe
- Department of Biomedical EngineeringThe Ohio State University270 Bevis Hall 1080 Carmack RdColumbus Ohio43210
| | - James W. Reinhardt
- Department of Biomedical EngineeringThe Ohio State University270 Bevis Hall 1080 Carmack RdColumbus Ohio43210
| | - Keith J. Gooch
- Department of Biomedical EngineeringThe Ohio State University270 Bevis Hall 1080 Carmack RdColumbus Ohio43210
- The Ohio State University, Davis Heart Lung Research Institute473 W 12th AveColumbus Ohio43210
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Shin HS, Kook YM, Hong HJ, Kim YM, Koh WG, Lim JY. Functional spheroid organization of human salivary gland cells cultured on hydrogel-micropatterned nanofibrous microwells. Acta Biomater 2016; 45:121-132. [PMID: 27592814 DOI: 10.1016/j.actbio.2016.08.058] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 08/19/2016] [Accepted: 08/31/2016] [Indexed: 01/07/2023]
Abstract
Development of a tissue-engineered, salivary bio-gland will benefit patients suffering from xerostomia due to loss of fluid-secreting acinar cells. This study was conducted to develop a bioengineering system to induce self-assembly of human parotid epithelial cells (hPECs) cultured on poly ethylene glycol (PEG) hydrogel-micropatterned polycaprolactone (PCL) nanofibrous microwells. Microwells were fabricated by photopatterning of PEG hydrogel in the presence of an electrospun PCL nanofibrous scaffold. hPECs were plated on plastic dishes, Matrigel, PCL nanofibers, or PCL nanofibrous microwells. When the cells were plated onto plastic, they did not form spheres, but aggregated to form 3D acinar-like spheroids when cultured on Matrigel, PCL, and PCL microwells, with the greatest aggregating potency being observed on the PCL microwells. The 3D-assembled spheroids in the PCL microwells expressed higher levels of salivary epithelial markers (α-amylase and AQP5), tight junction proteins (ZO-1 and occludin), adherence protein (E-cadherin), and cytoskeletal protein (F-actin) than those on the Matrigel and PCL. Furthermore, the 3D-assembled spheroids in the PCL microwells showed higher levels of α-amylase secretion and intracellular calcium concentration ([Ca2+]i) than those on the Matrigel and PCL nanofibers, suggesting more functional organization of hPECs. We established a bioengineering 3D culture system to promote robust and functional acinar-like organoids from hPECs. PCL nanofibrous microwells can be applied in the future for bioengineering of an artificial bio-salivary gland for restoration of salivary function. STATEMENT OF SIGNIFICANCE Three dimensional (3D) cultures of salivary glandular epithelial cells using nanofibrous bottom facilitate the formation of acinar-like organoids. In this study, we adapted a PEG hydrogel-micropatterned PCL nanofibrous microwell for the efficient bioengineering of human salivary gland organoids, in which we could easily produce uniform size of 3D organoids. This 3D culture system supports spherical organization, gene and protein expression of acinar markers, TJ proteins, adherence, and cytoskeletal proteins, as well as to promote epithelial structural integrity and acinar secretory functions, and results showed superior efficiency relative to Matrigel and nanofibrous scaffold culture. This 3D culture system has benefits in terms of inert, non-animal and serum-free culture conditions, as well as controllable spheroid size and scalable production of functional SG organoids and is applicable to bioengineering approaches for an artificial bio-gland, as well as to investigations of salivary gland physiology and regeneration.
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Affiliation(s)
- Hyun-Soo Shin
- Department of Otorhinolaryngology-Head and Neck Surgery, Inha University College of Medicine, Incheon, Republic of Korea
| | - Yun-Min Kook
- Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul, Republic of Korea
| | - Hye Jin Hong
- Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul, Republic of Korea
| | - Young-Mo Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Inha University College of Medicine, Incheon, Republic of Korea
| | - Won-Gun Koh
- Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul, Republic of Korea.
| | - Jae-Yol Lim
- Department of Otorhinolaryngology-Head and Neck Surgery, Inha University College of Medicine, Incheon, Republic of Korea.
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Lee JS, An SY, Kwon IK, Heo JS. Transdifferentiation of human periodontal ligament stem cells into pancreatic cell lineage. Cell Biochem Funct 2014; 32:605-11. [PMID: 25187163 DOI: 10.1002/cbf.3057] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 07/17/2014] [Accepted: 07/31/2014] [Indexed: 12/18/2022]
Abstract
Human periodontal ligament-derived stem cells (PDLSCs) demonstrate self-renewal capacity and multilineage differentiation potential. In this study, we investigated the transdifferentiation potential of human PDLSCs into pancreatic islet cells. To form three-dimensional (3D) clusters, PDLSCs were cultured in Matrigel with media containing differentiation-inducing agents. We found that after 6 days in culture, PDLSCs underwent morphological changes resembling pancreatic islet-like cell clusters (ICCs). The morphological characteristics of PDLSC-derived ICCs were further assessed using scanning electron microscopy analysis. Using reverse transcription-polymerase chain reaction analysis, we found that pluripotency genes were downregulated, whereas early endoderm and pancreatic differentiation genes were upregulated, in PDLSC-derived ICCs compared with undifferentiated PDLSCs. Furthermore, we found that PDLSC-derived ICCs were capable of secreting insulin in response to high concentrations of glucose, validating their functional differentiation into islet cells. Finally, we also performed dithizone staining, as well as immunofluorescence assays and fluorescence-activated cell sorting analysis for pancreatic differentiation markers, to confirm the differentiation status of PDLSC-derived ICCs. These results demonstrate that PDLSCs can transdifferentiate into functional pancreatic islet-like cells and provide a novel, alternative cell population for pancreatic repair.
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Affiliation(s)
- Jeong Seok Lee
- Department of Maxillofacial Biomedical Engineering and Institute of Oral Biology, School of Dentistry, Kyung Hee University, 26 Kyunghee-daero, Dongdaemun-gu, Seoul, 130-701, South Korea
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Barnes C, Speroni L, Quinn KP, Montevil M, Saetzler K, Bode-Animashaun G, McKerr G, Georgakoudi I, Downes CS, Sonnenschein C, Howard CV, Soto AM. From single cells to tissues: interactions between the matrix and human breast cells in real time. PLoS One 2014; 9:e93325. [PMID: 24691468 PMCID: PMC3972096 DOI: 10.1371/journal.pone.0093325] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 02/28/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Mammary gland morphogenesis involves ductal elongation, branching, and budding. All of these processes are mediated by stroma--epithelium interactions. Biomechanical factors, such as matrix stiffness, have been established as important factors in these interactions. For example, epithelial cells fail to form normal acinar structures in vitro in 3D gels that exceed the stiffness of a normal mammary gland. Additionally, heterogeneity in the spatial distribution of acini and ducts within individual collagen gels suggests that local organization of the matrix may guide morphogenesis. Here, we quantified the effects of both bulk material stiffness and local collagen fiber arrangement on epithelial morphogenesis. RESULTS The formation of ducts and acini from single cells and the reorganization of the collagen fiber network were quantified using time-lapse confocal microscopy. MCF10A cells organized the surrounding collagen fibers during the first twelve hours after seeding. Collagen fiber density and alignment relative to the epithelial surface significantly increased within the first twelve hours and were a major influence in the shaping of the mammary epithelium. The addition of Matrigel to the collagen fiber network impaired cell-mediated reorganization of the matrix and increased the probability of spheroidal acini rather than branching ducts. The mechanical anisotropy created by regions of highly aligned collagen fibers facilitated elongation and branching, which was significantly correlated with fiber organization. In contrast, changes in bulk stiffness were not a strong predictor of this epithelial morphology. CONCLUSIONS Localized regions of collagen fiber alignment are required for ductal elongation and branching suggesting the importance of local mechanical anisotropy in mammary epithelial morphogenesis. Similar principles may govern the morphology of branching and budding in other tissues and organs.
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Affiliation(s)
- Clifford Barnes
- School of Biomedical Sciences, University of Ulster, Coleraine, County Londonderry, United Kingdom
| | - Lucia Speroni
- Department of Integrative Physiology and Pathobiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Kyle P. Quinn
- Department of Biomedical Engineering, Tufts University, Boston, Massachusetts, United States of America
| | - Mael Montevil
- Department of Integrative Physiology and Pathobiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Kurt Saetzler
- School of Biomedical Sciences, University of Ulster, Coleraine, County Londonderry, United Kingdom
| | | | - George McKerr
- School of Biomedical Sciences, University of Ulster, Coleraine, County Londonderry, United Kingdom
| | - Irene Georgakoudi
- Department of Biomedical Engineering, Tufts University, Boston, Massachusetts, United States of America
| | - C. Stephen Downes
- School of Biomedical Sciences, University of Ulster, Coleraine, County Londonderry, United Kingdom
| | - Carlos Sonnenschein
- School of Biomedical Sciences, University of Ulster, Coleraine, County Londonderry, United Kingdom
- Department of Integrative Physiology and Pathobiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - C. Vyvyan Howard
- School of Biomedical Sciences, University of Ulster, Coleraine, County Londonderry, United Kingdom
| | - Ana M. Soto
- School of Biomedical Sciences, University of Ulster, Coleraine, County Londonderry, United Kingdom
- Department of Integrative Physiology and Pathobiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
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McLeod C, Higgins J, Miroshnikova Y, Liu R, Garrett A, Sarang-Sieminski AL. Microscopic matrix remodeling precedes endothelial morphological changes during capillary morphogenesis. J Biomech Eng 2014; 135:71002. [PMID: 23722263 DOI: 10.1115/1.4023984] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 03/08/2013] [Indexed: 11/08/2022]
Abstract
The formation of microvascular networks (MVNs) is influenced by many aspects of the microenvironment, including soluble and insoluble biochemical factors and the biophysical properties of the surrounding matrix. It has also become clear that a dynamic and reciprocal interaction between the matrix and cells influences cell behavior. In particular, local matrix remodeling may play a role in driving cellular behaviors, such as MVN formation. In order to explore the role of matrix remodeling, an in vitro model of MVN formation involving suspending human umbilical vein endothelial cells within collagen hydrogels was used. The resulting cell and matrix morphology were microscopically observed and quantitative metrics of MVN formation and collagen gathering were applied to the resulting images. The macroscopic compaction of collagen gels correlates with the extent of MVN formation in gels of different stiffness values, with compaction preceding elongation leading to MVN formation. Furthermore, the microscopic analysis of collagen between cells at early timepoints demonstrates the alignment and gathering of collagen between individual adjacent cells. The results presented are consistent with the hypothesis that endothelial cells need to gather and align collagen between them as an early step in MVN formation.
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Affiliation(s)
- Claire McLeod
- Franklin W. Olin College of Engineering, Needham, MA 02492, USA
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Ma X, Schickel ME, Stevenson MD, Sarang-Sieminski AL, Gooch KJ, Ghadiali SN, Hart RT. Fibers in the extracellular matrix enable long-range stress transmission between cells. Biophys J 2013; 104:1410-8. [PMID: 23561517 DOI: 10.1016/j.bpj.2013.02.017] [Citation(s) in RCA: 127] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 01/15/2013] [Accepted: 02/12/2013] [Indexed: 10/27/2022] Open
Abstract
Cells can sense, signal, and organize via mechanical forces. The ability of cells to mechanically sense and respond to the presence of other cells over relatively long distances (e.g., ∼100 μm, or ∼10 cell-diameters) across extracellular matrix (ECM) has been attributed to the strain-hardening behavior of the ECM. In this study, we explore an alternative hypothesis: the fibrous nature of the ECM makes long-range stress transmission possible and provides an important mechanism for long-range cell-cell mechanical signaling. To test this hypothesis, confocal reflectance microscopy was used to develop image-based finite-element models of stress transmission within fibroblast-seeded collagen gels. Models that account for the gel's fibrous nature were compared with homogenous linear-elastic and strain-hardening models to investigate the mechanisms of stress propagation. Experimentally, cells were observed to compact the collagen gel and align collagen fibers between neighboring cells within 24 h. Finite-element analysis revealed that stresses generated by a centripetally contracting cell boundary are concentrated in the relatively stiff ECM fibers and are propagated farther in a fibrous matrix as compared to homogeneous linear elastic or strain-hardening materials. These results support the hypothesis that ECM fibers, especially aligned ones, play an important role in long-range stress transmission.
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Affiliation(s)
- Xiaoyue Ma
- The Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio, USA
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Stevenson MD, Piristine H, Hogrebe NJ, Nocera TM, Boehm MW, Reen RK, Koelling KW, Agarwal G, Sarang-Sieminski AL, Gooch KJ. A self-assembling peptide matrix used to control stiffness and binding site density supports the formation of microvascular networks in three dimensions. Acta Biomater 2013; 9:7651-61. [PMID: 23603000 DOI: 10.1016/j.actbio.2013.04.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 03/01/2013] [Accepted: 04/01/2013] [Indexed: 01/13/2023]
Abstract
A three-dimensional (3-D) cell culture system that allows control of both substrate stiffness and integrin binding density was created and characterized. This system consisted of two self-assembling peptide (SAP) sequences that were mixed in different ratios to achieve the desired gel stiffness and adhesiveness. The specific peptides used were KFE ((acetyl)-FKFEFKFE-CONH2), which has previously been reported not to support cell adhesion or MVN formation, and KFE-RGD ((acetyl)-GRGDSP-GG-FKFEFKFE-CONH2), which is a similar sequence that incorporates the RGD integrin binding site. Storage modulus for these gels ranged from ∼60 to 6000Pa, depending on their composition and concentration. Atomic force microscopy revealed ECM-like fiber microarchitecture of gels consisting of both pure KFE and pure KFE-RGD as well as mixtures of the two peptides. This system was used to study the contributions of both matrix stiffness and adhesiveness on microvascular network (MVN) formation of endothelial cells and the morphology of human mesenchymal stem cells (hMSC). When endothelial cells were encapsulated within 3-D gel matrices without binding sites, little cell elongation and no network formation occurred, regardless of the stiffness. In contrast, matrices containing the RGD binding site facilitated robust MVN formation, and the extent of this MVN formation was inversely proportional to matrix stiffness. Compared with a matrix of the same stiffness with no binding sites, a matrix containing RGD-functionalized peptides resulted in a ∼2.5-fold increase in the average length of network structure, which was used as a quantitative measure of MVN formation. Matrices with hMSC facilitated an increased number and length of cellular projections at higher stiffness when RGD was present, but induced a round morphology at every stiffness when RGD was absent. Taken together, these results demonstrate the ability to control both substrate stiffness and binding site density within 3-D cell-populated gels and reveal an important role for both stiffness and adhesion on cellular behavior that is cell-type specific.
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Affiliation(s)
- M D Stevenson
- The Ohio State University, Department of Biomedical Engineering, 270 Bevis Hall 1080 Carmack Rd., Columbus, OH 43210, USA
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Williams C, Rauch MF, Michaud M, Robinson R, Xu H, Madri J, Lavik E. Short term interactions with long term consequences: modulation of chimeric vessels by neural progenitors. PLoS One 2012; 7:e53208. [PMID: 23300890 PMCID: PMC3531360 DOI: 10.1371/journal.pone.0053208] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 11/27/2012] [Indexed: 12/26/2022] Open
Abstract
Vessels are a critical and necessary component of most tissues, and there has been substantial research investigating vessel formation and stabilization. Several groups have investigated coculturing endothelial cells with a second cell type to promote formation and stabilization of vessels. Some have noted that long-term vessels derived from implanted cocultures are often chimeric consisting of both host and donor cells. The questions arise as to whether the coculture cell might impact the chimeric nature of the microvessels and can modulate the density of donor cells over time. If long-term engineered microvessels are primarily of host origin, any impairment of the host's angiogenic ability has significant implications for the long-term success of the implant. If one can modulate the host versus donor response, one may be able to overcome a host's angiogenic impairment. Furthermore, if one can modulate the donor contribution, one may be able to engineer microvascular networks to deliver molecules a patient lacks systemically for long times. To investigate the impact of the cocultured cell on the host versus donor contributions of endothelial cells in engineered microvascular networks, we varied the ratio of the neural progenitors to endothelial cells in subcutaneously implanted poly(ethylene glycol)/poly-L-lysine hydrogels. We found that the coculture of neural progenitors with endothelial cells led to the formation of chimeric host-donor vessels, and the ratio of neural progenitors has a significant impact on the long term residence of donor endothelial cells in engineered microvascular networks in vivo even though the neural progenitors are only present transiently in the system. We attribute this to the short term paracrine signaling between the two cell types. This suggests that one can modulate the host versus donor contributions using short-term paracrine signaling which has broad implications for the application of engineered microvascular networks and cellular therapy more broadly.
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Affiliation(s)
- Cicely Williams
- Interdepartmental Neuroscience Program, Yale University, New Haven, Connecticut, United States of America
| | - Millicent Ford Rauch
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut, United States of America
| | - Michael Michaud
- Department of Pathology, Yale University, New Haven, Connecticut, United States of America
| | - Rebecca Robinson
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut, United States of America
| | - Hao Xu
- Department of Biomedical Engineering, Washington University, St. Louis, Missouri, United States of America
| | - Joseph Madri
- Department of Pathology, Yale University, New Haven, Connecticut, United States of America
| | - Erin Lavik
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, United States of America
- * E-mail:
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Shi Y, Dong Y, Duan Y, Jiang X, Chen C, Deng L. Substrate stiffness influences TGF-β1-induced differentiation of bronchial fibroblasts into myofibroblasts in airway remodeling. Mol Med Rep 2012; 7:419-24. [PMID: 23229284 DOI: 10.3892/mmr.2012.1213] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 11/13/2012] [Indexed: 11/06/2022] Open
Abstract
Chronic inflammation and remodeling of the bronchial wall are basic hallmarks of asthma. During the process of bronchial wall remodeling, inflammatory factors, such as transforming growth factor-β1 (TGF-β1), are known to induce the differentiation of fibroblasts into myofibroblasts, which leads to excessive synthesis and secretion of extracellular matrix (ECM) proteins, thus thickening and stiffening the basement membrane. However, it has not been thoroughly studied whether or not substrate stiffening affects the TGF-β1‑induced myofibroblast differentiation. In the present study, the influence of substrate stiffness on the process of bronchial fibroblast differentiation into myofibroblasts in the presence of TGF-β1 was investigated. To address this question, we synthesized polydimethylsiloxane (PDMS) substrates with varying degrees of stiffness (Young's modulus of 1, 10 and 50 kPa, respectively). We cultured bronchial fibroblasts on the substrates of varying stiffness in media containing TGF-β1 (10 ng/ml) to stimulate the differentiation of fibroblasts into myofibroblasts. Myofibroblast differentiation was examined using semi-quantitative RT-PCR for the expression of α-smooth muscle actin (α-SMA) mRNA and collagen I mRNA, the enzyme-linked immunosorbent assay method was used to assess the expression of collagen I protein and western blotting to assess the expression of α-SMA protein. The optical magnetic twisting cytometry (OMTC) method was used for the changing of cell mechanical properties. Our findings suggest that when fibroblasts were incubated with TGF-β1 (10 ng/ml) on substrate of varying stiffness, the differentiation of fibroblasts into myofibroblasts was enhanced by increasing substrate stiffness. Compared with those cultured on substrate with Young's modulus of 1 kPa, the mRNA and protein expression of collagen I and α-SMA of fibroblasts cultured on substrates with Young's modulus of 10 and 50 kPa were increased. Furthermore, with the increase of substrate stiffness, the cell stiffness and contractility were also increased, which also indicated further aggravation of asthma. This finding may help better understand the underlying mechanisms of hyperplasia of myofibroblasts in asthma, which has a marked significance in the therapy of asthma.
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Affiliation(s)
- Yanling Shi
- Key Laboratory of Biorheological Science and Technology, Ministry of Education and Bioengineering College, Chongqing University, Chongqing 400044, P.R. China
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11
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Maria OM, Zeitouni A, Gologan O, Tran SD. Matrigel improves functional properties of primary human salivary gland cells. Tissue Eng Part A 2011; 17:1229-38. [PMID: 21189069 DOI: 10.1089/ten.tea.2010.0297] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Currently, there is no effective treatment available to patients with irreversible loss of functional salivary acini caused by Sjogren's syndrome or after radiotherapy for head and neck cancer. A tissue-engineered artificial salivary gland would help these patients. The graft cells for this device must establish tight junctions in addition to being of fluid-secretory nature. This study analyzed a graft source from human salivary glands (huSG) cultured on Matrigel. Cells were obtained from parotid and submandibular glands, expanded in vitro, and then plated on either Matrigel-coated (2 mg/mL) or uncoated culture dish. Immunohistochemistry, transmission electron microscopy, quantitative real-time-polymerase chain reaction, Western blot, and transepithelial electrical resistance were employed. On Matrigel, huSG cells adopted an acinar phenotype by forming three-dimensional acinar-like units (within 24 h of plating) as well as a monolayer of cells. On uncoated surfaces (plastic), huSG cells only formed monolayers of ductal cells. Both types of culture conditions allowed huSG cells to express tight junction proteins (claudin-1, -2, -3, -4; occludin; JAM-A; and ZO-1) and adequate transepithelial electrical resistance. Importantly, 99% of huSG cells on Matrigel expressed α-amylase and the water channel protein Aquaporin-5, as compared to <5% of huSG cells on plastic. Transmission electron microscopy confirmed an acinar phenotype with many secretory granules. Matrigel increased the secretion of α-amylase two to five folds into the media, downregulated certain salivary genes, and regulated the translation of acinar proteins. This three-dimensional in vitro serum-free cell culture method allows the organization and differentiation of huSG cells into salivary cells with an acinar phenotype.
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Affiliation(s)
- Ola M Maria
- Faculty of Dentistry, McGill University, Montreal, Canada
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12
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Poly(amidoamine) Hydrogels as Scaffolds for Cell Culturing and Conduits for Peripheral Nerve Regeneration. INT J POLYM SCI 2011. [DOI: 10.1155/2011/161749] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Biodegradable and biocompatible poly(amidoamine)-(PAA-) based hydrogels have been considered for different tissue engineering applications. First-generation AGMA1 hydrogels, amphoteric but prevailing cationic hydrogels containing carboxylic and guanidine groups as side substituents, show satisfactory results in terms of adhesion and proliferation properties towards different cell lines. Unfortunately, these hydrogels are very swellable materials, breakable on handling, and have been found inadequate for other applications. To overcome this problem, second-generation AGMA1 hydrogels have been prepared adopting a new synthetic method. These new hydrogels exhibit good biological propertiesin vitrowith satisfactory mechanical characteristics. They are obtained in different forms and shapes and successfully testedin vivofor the regeneration of peripheral nerves. This paper reports on our recent efforts in the use of first-and second-generation PAA hydrogels as substrates for cell culturing and tubular scaffold for peripheral nerve regeneration.
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13
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Alvarez-Vallina L, Sanz L. The therapeutic potential of engineered human neovessels for cell-based gene therapy. Expert Opin Biol Ther 2010; 11:67-76. [PMID: 21080857 DOI: 10.1517/14712598.2011.538378] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
IMPORTANCE OF THE FIELD Several works have shown the feasibility of engineering functional blood vessels in vivo using human endothelial cells and mural cells. In this context, the genetic modification of endothelial cells would ensure the secretion of a therapeutic protein into the systemic circulation for a prolonged period of time. AREAS COVERED IN THIS REVIEW We discuss the different strategies aimed at the formation of long-lasting neovessels in vivo, using human endothelial and mural cells. The main focus is the potential of these constructs in gene therapy strategies for the in vivo production of therapeutic proteins. WHAT THE READER WILL GAIN The reader will have an outline of the different types of cells that have been used for microvessel engineering in vivo, as well as scaffolds employed to seed these cells. We provide a critical review of their advantages and drawbacks, along with examples of their potential in cell-based gene therapy strategies. TAKE HOME MESSAGE There is a real potential for neovessels derived from human endothelial and mural cells to be incorporated in clinical interventions, either as a cell-based gene therapy to produce a therapeutic protein or as a component of engineered tissue constructs in regenerative medicine.
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Affiliation(s)
- Luís Alvarez-Vallina
- Molecular Immunology Unit, Hospital Universitario Puerta de Hierro, Madrid, Spain.
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Fedorovich NE, Haverslag RT, Dhert WJ, Alblas J. The Role of Endothelial Progenitor Cells in Prevascularized Bone Tissue Engineering: Development of Heterogeneous Constructs. Tissue Eng Part A 2010; 16:2355-67. [DOI: 10.1089/ten.tea.2009.0603] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Affiliation(s)
- Natalja E. Fedorovich
- Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - René T. Haverslag
- Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Wouter J.A. Dhert
- Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands
- Faculty of Veterinary Medicine, University Utrecht, Utrecht, The Netherlands
| | - Jacqueline Alblas
- Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands
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15
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Abstract
Angiogenesis is the process by which endothelial cells grow and disassemble into functional blood vessels. In this study, we examine the fundamental processes that control the assembly of endothelial cells into networks in vitro. Network assembly is known to be influenced by matrix mechanics and chemical signals. However, the roles of substrate stiffness and chemical signals in network formation is unclear. In this study, human umbilical vein endothelial cells (HUVECs) were seeded onto RGD or GFOGER functionalized polyacrylamide gels of varying stiffness. Cells were either treated with bFGF, VEGF, or left untreated and observed over time. We found that cells form stable networks on soft gels (Young's modulus 140 Pa) when untreated but that growth factors induce increased cell migration which leads to network instability. On stiffer substrates (Young's modulus 2500 Pa) cells do not assemble into networks either with or without growth factors in any combination. Our results indicate that cells assemble to networks below a critical compliance, that a critical cell density is needed for network formation, and that growth factors can inhibit network formation through an increase in motility.
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16
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Akiyama M, Nakamura M. Bone regeneration and neovascularization processes in a pellet culture system for periosteal cells. Cell Transplant 2009; 18:443-52. [PMID: 19622231 DOI: 10.3727/096368909788809820] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Reliable bone regeneration can be achieved with a pellet culture system using bovine periosteal cells. However, bone regeneration and neovascularization processes in this system have remained unclear. The present study aimed to clarify the extracellular environment and neovascularization process. To detect components of the extracellular matrix secreted by cells and to identify the conditions necessary for bone regeneration in the body, Western blotting and in vivo tests in nude mice were performed. Cells were cultured with or without ascorbic acid and culture supernatant was precipitated. Western blotting showed that culture supernatant contained collagen type I, procollagen type I, and procollagen type I C-terminus when cells were cultured with ascorbic acid. Cells cultured with ascorbic acid formed partial bony tissues at 2 weeks after grafting to nude mice, while bone formation was missing without ascorbic acid. Immunostaining was performed using species-specific vascular endothelial cell markers to ascertain whether vascular endothelial cells were bovine or murine (nude mouse). Immunohistological methods showed vascular endothelial cells in osseous tissue formed in the subcutaneous tissue of nude mice were murine. Extracellular matrix synthesis in vitro and host blood flow in vivo are essential for bone regeneration.
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Affiliation(s)
- Mari Akiyama
- Department of Biomaterials, Osaka Dental University, Osaka, Japan.
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17
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Byfield FJ, Reen RK, Shentu TP, Levitan I, Gooch KJ. Endothelial actin and cell stiffness is modulated by substrate stiffness in 2D and 3D. J Biomech 2009; 42:1114-9. [PMID: 19356760 DOI: 10.1016/j.jbiomech.2009.02.012] [Citation(s) in RCA: 158] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2007] [Revised: 01/23/2009] [Accepted: 02/06/2009] [Indexed: 11/18/2022]
Abstract
There is a growing appreciation of the profound effects that passive mechanical properties, especially the stiffness of the local environment, can have on cellular functions. Many experiments are conducted in a 2D geometry (i.e., cells grown on top of substrates of varying stiffness), which is a simplification of the 3D environment often experienced by cells in vivo. To determine how matrix dimensionality might modulate the effect of matrix stiffness on actin and cell stiffness, endothelial cells were cultured on top of and within substrates of various stiffnesses. Endothelial cells were cultured within compliant (1.0-1.5mg/ml, 124+/-8 to 202+/-27Pa) and stiff (3.0mg/ml, 502+/-48Pa) type-I collagen gels. Cells elongated and formed microvascular-like networks in both sets of gels as seen in previous studies. Cells in stiffer gels exhibited more pronounced stress fibers and approximately 1.5-fold greater staining for actin. As actin is a major determinant of a cell's mechanical properties, we hypothesized that cells in stiff gels will themselves be stiffer. To test this hypothesis, cells were isolated from the gels and their stiffness was assessed using micropipette aspiration. Cells isolated from relatively compliant gels were 1.9-fold more compliant than cells isolated from relatively stiff gels (p<0.05). Similarly, cells cultured on top of 1700Pa polyacrylamide gels were 2.0-fold more compliant that those cultured on 9000Pa (p<0.05). These data demonstrate that extracellular substrate stiffness regulates endothelial stiffness in both three- and two-dimensional environments, though the range of stiffnesses that cells respond to vary significantly in different environments.
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Affiliation(s)
- Fitzroy J Byfield
- Institute of Medicine and Engineering, University of Pennsylvania, USA
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18
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Boretti MI, Gooch KJ. Effect of extracellular matrix and 3D morphogenesis on islet hormone gene expression by Ngn3-infected mouse pancreatic ductal epithelial cells. Tissue Eng Part A 2009; 14:1927-37. [PMID: 18694323 DOI: 10.1089/ten.tea.2007.0338] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
We verified the proendocrine effects of Matrigel overlay in an adult mouse pancreatic ductal epithelial cells (PDEC) model and then decomposed the environment to delineate the specific factors responsible for this effect. Following overlay with Matrigel, supplementation of Matrigel to the culture medium, or suspension within Matrigel, neurogenin3-infected mouse PDEC underwent dramatic morphogenesis, transitioning from a two-dimensional monolayer to three-dimensional (3D) cysts. Along with these morphogenic changes, the cells displayed up to approximately sixfold increase in mRNA for the islet hormones somatostatin and ghrelin. Following overlay with collagen or suspension within collagen, PDEC also displayed similar morphogenic changes, but a much smaller increase in expression was observed (1.5- to 3-fold), suggesting that while 3D morphogenesis is capable of independently enhancing islet differentiation, biochemical factors present within Matrigel also have proendocrine effects. Following suspension within laminin gels, PDEC formed 3D cysts and also displayed an increase in islet hormone expression, similar to those cultured within Matrigel. However, medium supplemented with laminin failed to promote 3D morphogenesis of PDEC or enhance islet hormone expression, suggesting that while laminin is capable of enhancing islet hormone expression, 3D morphogenesis is required for this effect. Cell clustering appeared to maximize differentiation, as PDEC cultured on Matrigel formed aggregates and stimulated the highest expression of somatostatin and ghrelin (up to approximately 200-fold).
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Affiliation(s)
- Michael Ian Boretti
- Department of Bioengineering, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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19
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Sieminski AL, Semino CE, Gong H, Kamm RD. Primary sequence of ionic self-assembling peptide gels affects endothelial cell adhesion and capillary morphogenesis. J Biomed Mater Res A 2008; 87:494-504. [DOI: 10.1002/jbm.a.31785] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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20
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Luong E, Gerecht S. Stem cells and scaffolds for vascularizing engineered tissue constructs. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2008; 114:129-72. [PMID: 19082932 DOI: 10.1007/10_2008_8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The clinical impact of tissue engineering depends upon our ability to direct cells to form tissues with characteristic structural and mechanical properties from the molecular level up to organized tissue. Induction and creation of functional vascular networks has been one of the main goals of tissue engineering either in vitro, for the transplantation of prevascularized constructs, or in vivo, for cellular organization within the implantation site. In most cases, tissue engineering attempts to recapitulate certain aspects of normal development in order to stimulate cell differentiation and functional tissue assembly. The induction of tissue growth generally involves the use of biodegradable and bioactive materials designed, ideally, to provide a mechanical, physical, and biochemical template for tissue regeneration. Human embryonic stem cells (hESCs), derived from the inner cell mass of a developing blastocyst, are capable of differentiating into all cell types of the body. Specifically, hESCs have the capability to differentiate and form blood vessels de novo in a process called vasculogenesis. Human ESC-derived endothelial progenitor cells (EPCs) and endothelial cells have substantial potential for microvessel formation, in vitro and in vivo. Human adult EPCs are being isolated to understand the fundamental biology of how these cells are regulated as a population and to explore whether these cells can be differentiated and reimplanted as a cellular therapy in order to arrest or even reverse damaged vasculature. This chapter focuses on advances made toward the generation and engineering of functional vascular tissue, focusing on both the scaffolds - the synthetic and biopolymer materials - and the cell sources - hESCs and hEPCs.
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Affiliation(s)
- E Luong
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD, 21218, USA
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21
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Finkenzeller G, Torio-Padron N, Momeni A, Mehlhorn AT, Stark GB. In vitro angiogenesis properties of endothelial progenitor cells: a promising tool for vascularization of ex vivo engineered tissues. ACTA ACUST UNITED AC 2007; 13:1413-20. [PMID: 17550338 DOI: 10.1089/ten.2006.0369] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Survival of ex vivo constructed tissues after transplantation is limited by insufficient oxygen and nutrient supply. Therefore, strategies aiming at the improvement of neovascularization of engineered tissues are a key issue. A method to enhance graft vascularization is to establish a primitive vascular plexus within the graft before transplantation by the use of cellular-based concepts. To explore the utility of endothelial progenitor cells (EPCs) for the ex vivo vascularization of tissue engineered grafts, we analyzed the in vitro angiogenic properties of this cell type in two different angiogenesis models: the 3-dimensional spheroid sprouting assay and the 2-dimensional matrigel assay. In both assays, EPCs were able to form tubelike structures, resembling early capillaries. This process was significantly enhanced by the addition of angiogenic growth factors. Direct comparison between EPCs and mature endothelial cells, represented by human umbilical vein endothelial cells (HUVECs), revealed that both cell types displayed an almost identical angiogenic potential. Other functional in vitro parameters such as angiogenic growth factor induced cell proliferation and cell survival were investigated as well, revealing a significantly decreased level of apoptosis of EPCs in relation to HUVECs under serum-deprived conditions. The observed survival advantage of EPCs along with the observation that EPCs perform very well in the above mentioned in vitro angiogenesis assays, make them an ideal autologous cell source for vascularization of ex vivo generated tissues. The attractiveness of this cell type for tissue engineering applications is strengthened further by the fact that these cells can be easily isolated from the peripheral blood of patients, thereby eliminating donor site morbidity.
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Affiliation(s)
- Günter Finkenzeller
- Department of Plastic and Hand Surgery, University of Freiburg Medical Center, Hugstetter Str. 55, D-79106 Freiburg, Germany.
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22
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Sieminski AL, Was AS, Kim G, Gong H, Kamm RD. The Stiffness of Three-dimensional Ionic Self-assembling Peptide Gels Affects the Extent of Capillary-like Network Formation. Cell Biochem Biophys 2007; 49:73-83. [PMID: 17906362 DOI: 10.1007/s12013-007-0046-1] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2006] [Revised: 06/27/2007] [Accepted: 07/06/2007] [Indexed: 10/23/2022]
Abstract
Improving our ability to control capillary morphogenesis has implications for not only better understanding of basic biology, but also for applications in tissue engineering and in vitro testing. Numerous biomaterials have been investigated as cellular supports for these applications and the biophysical environment biomaterials provide to cells has been increasingly recognized as an important factor in directing cell function. Here, the ability of ionic self-assembling peptide gels to support capillary morphogenesis and the effect of their mechanical properties is investigated. When placed in a physiological salt solution, these oligopeptides spontaneously self-assemble into gels with an extracellular matrix (ECM)-like microarchitecture. To evaluate the ability of three-dimensional (3D) self-assembled peptide gels to support capillary-like network formation, human umbilical vein endothelial cells (HUVECs) were embedded within RAD16-I ((RADA)4) or RAD16-II ((RARADADA)2) peptide gels with various stiffness values. As peptide stiffness is decreased cells show increased elongation and are increasingly able to contract gels. The observation that capillary morphogenesis is favored in more malleable substrates is consistent with previous reports using natural biomaterials. The structural properties of peptide gels and their ability to support capillary morphogenesis in vitro make them promising biomaterials to investigate for numerous biomedical applications.
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Affiliation(s)
- A L Sieminski
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
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23
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Boretti MI, Gooch KJ. Transgene Expression Level and Inherent Differences in Target Gene Activation Determine the Rate and Fate of Neurogenin3-Mediated Islet Cell DifferentiationIn Vitro. ACTA ACUST UNITED AC 2007; 13:775-88. [PMID: 17355210 DOI: 10.1089/ten.2006.0258] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A significant challenge in many areas of tissue engineering is a readily available source of cells. One approach to address this challenge is to direct the differentiation of expandable stem or progenitor cells or the transdifferentiation of an already differentiated cell type to the desired cell type. A variety of methods have been explored for directing cell differentiation, including the ectopic expression of transcriptional factors that are known to influence cell differentiation during development. One such transcription factor, neurogenin3 (Ngn3), plays a critical role in islet cell development in vivo. Ectopic expression of Ngn3 in various cell types has previously been shown to promote differentiation toward islet cell phenotypes, but the overall efficiency of this differentiation and the specific islet cell type produced vary widely between reports. The present work evaluates the hypotheses that cellular response is determined by (1) differentiation status of the starting cell, (2) basal expression of other transcriptional factors, and (3) level of ectopic Ngn3 expression. Retroviral vectors were used to express Ngn3 in primary adult pancreatic ductal epithelial cells (PDEC), embryonic and adult stem cells (ESC and ASC), and transformed mouse pancreatic adenocarcinoma (mPAC) cells in vitro. Changes in phenotypes were assessed using quantitative reverse transcription polymerase chain reaction (qRT-PCR), gene arrays, and immunohistochemistry. When Ngn3 was ectopically expressed in mouse and rat PDEC, downstream transcription factors (e.g., NeuroD, Nkx2.2, Isl-1) and endocrine hormones (most notably, ghrelin and somatostatin) were highly upregulated in a dose-dependent manner. In comparison to mPAC and mouse embryonic stem cells (mESC), PDEC displayed higher expression of most islet markers after normalization to Ngn3 levels. Differences in the basal expression and activation of transcription factors (e.g., Pax4, Pax6, and Nkx6.1) were observed between cell types, suggesting a mechanism by which precursors might preferentially generate different islet cell types.
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Affiliation(s)
- Michael I Boretti
- Department of Bioengineering, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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24
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Wenger A, Kowalewski N, Stahl A, Mehlhorn AT, Schmal H, Stark GB, Finkenzeller G. Development and characterization of a spheroidal coculture model of endothelial cells and fibroblasts for improving angiogenesis in tissue engineering. Cells Tissues Organs 2006; 181:80-8. [PMID: 16534202 DOI: 10.1159/000091097] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2005] [Indexed: 01/29/2023] Open
Abstract
Neovascularization is a critical step in tissue engineering applications since implantation of voluminous grafts without sufficient vascularity results in hypoxic cell death of central tissues. We have developed a three-dimensional spheroidal coculture system consisting of human umbilical vein endothelial cells (HUVECs) and human primary fibroblasts (hFBs) to improve angiogenesis in tissue engineering applications. Morphological analysis of cryosections from HUVEC/hFB cospheroids revealed a characteristic temporal and spatial organization with HUVECs located in the center of the cospheroid and a peripheral localization of fibroblasts. In coculture spheroids, the level of apoptosis of endothelial cells was strongly decreased upon cocultivation with fibroblasts. Collagen-embedded HUVEC spheroids develop numerous lumenized capillary-like sprouts. This was also apparent for HUVEC/hFB cospheroids, albeit to a lesser extent. Quantification of cumulative sprout length revealed an approximately 35% reduction in endothelial cell sprouting upon cocultivation with fibroblasts in cospheroids. The slight reduction in endothelial cell sprouting was not mediated by a paracrine mechanism but is most likely due to the formation of heterogenic cell contacts between HUVECs and hFBs within the cospheroid. The model system introduced in this study is suitable for the development of a preformed lumenized capillary-like network ex vivo and may therefore be useful for improving angiogenesis in in vivo tissue engineering applications.
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Affiliation(s)
- Andreas Wenger
- Department of Plastic, University of Freiburg Medical Center, Freiburg, Germany
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25
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Sieminski AL, Hebbel RP, Gooch KJ. Improved microvascular network in vitro by human blood outgrowth endothelial cells relative to vessel-derived endothelial cells. ACTA ACUST UNITED AC 2005; 11:1332-45. [PMID: 16259589 DOI: 10.1089/ten.2005.11.1332] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Evidence suggests that bone marrow-derived cells circulating in adult blood, sometimes called endothelial progenitor cells, contribute to neovascularization in vivo and give rise to cells expressing endothelial markers in culture. To explore the utility of blood-derived cells expressing an endothelial phenotype for creating tissue-engineered microvascular networks, we employed a three-dimensional in vitro angiogenesis model to compare microvascular network formation by human blood outgrowth endothelial cells (HBOECs) with three human vessel-derived endothelial cell (EC) types: human umbilical vein ECs (HUVECs), and adult and neonatal human microvascular ECs. Under every condition investigated, HBOECs within collagen gels elongated significantly more than any other cell type. Under all conditions investigated, gel contraction and cell elongation were correlated, with HBOECs demonstrating the largest generation of force. HBOECs did not exhibit a survival advantage, nor did they enhance elongation of HUVECs when the two cell types were cocultured. Network formation of both HBOECs and HUVECs was inhibited by blocking antibodies to alpha2beta1, but not alpha(v)beta3, integrins. Taken together, these data suggest that superior network exhibited by HBOECs relative to vessel-derived endothelial cells is not due to a survival advantage, use of different integrins, or secretion of an autocrine/paracrine factor, but may be related to increased force generation.
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Affiliation(s)
- A L Sieminski
- Department of Bioengineering and Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6392, USA
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26
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Brey EM, Uriel S, Greisler HP, McIntire LV. Therapeutic neovascularization: contributions from bioengineering. ACTA ACUST UNITED AC 2005; 11:567-84. [PMID: 15869435 DOI: 10.1089/ten.2005.11.567] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A number of pathological entities and surgical interventions could benefit from therapeutic stimulation of new blood vessel formation. Although strategies designed for promoting neovascularization have shown promise in preclinical models, translation to human application has met with limited success when angiogenesis is used as the single therapeutic mechanism. While clinical protocols continue to be optimized, a number of exciting new approaches are being developed. Bioengineering has played an important role in the progress of many of these innovative new strategies. In this review, we present a general outline of therapeutic neovascularization, with an emphasis on investigations using engineering principles to address this vexing clinical problem. In addition, we identify some limitations and suggest areas for future research.
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Affiliation(s)
- Eric M Brey
- Pritzker Institute of Biomedical Science and Engineering, Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, 60616, USA.
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27
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Levenberg S, Rouwkema J, Macdonald M, Garfein ES, Kohane DS, Darland DC, Marini R, van Blitterswijk CA, Mulligan RC, D'Amore PA, Langer R. Engineering vascularized skeletal muscle tissue. Nat Biotechnol 2005; 23:879-84. [PMID: 15965465 DOI: 10.1038/nbt1109] [Citation(s) in RCA: 848] [Impact Index Per Article: 44.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2005] [Accepted: 05/02/2005] [Indexed: 11/09/2022]
Abstract
One of the major obstacles in engineering thick, complex tissues such as muscle is the need to vascularize the tissue in vitro. Vascularization in vitro could maintain cell viability during tissue growth, induce structural organization and promote vascularization upon implantation. Here we describe the induction of endothelial vessel networks in engineered skeletal muscle tissue constructs using a three-dimensional multiculture system consisting of myoblasts, embryonic fibroblasts and endothelial cells coseeded on highly porous, biodegradable polymer scaffolds. Analysis of the conditions for induction and stabilization of the vessels in vitro showed that addition of embryonic fibroblasts increased the levels of vascular endothelial growth factor expression in the construct and promoted formation and stabilization of the endothelial vessels. We studied the survival and vascularization of the engineered muscle implants in vivo in three different models. Prevascularization improved the vascularization, blood perfusion and survival of the muscle tissue constructs after transplantation.
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28
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Lowman AM, Dziubla TD, Bures P, Peppas NA. STRUCTURAL AND DYNAMIC RESPONSE OF NEUTRAL AND INTELLIGENT NETWORKS IN BIOMEDICAL ENVIRONMENTS. ADVANCES IN CHEMICAL ENGINEERING: MOLECULAR AND CELLULAR FOUNDATIONS OF BIOMATERIALS 2004. [DOI: 10.1016/s0065-2377(03)29004-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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