451
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Kim HN, Kang DH, Kim MS, Jiao A, Kim DH, Suh KY. Patterning methods for polymers in cell and tissue engineering. Ann Biomed Eng 2012; 40:1339-55. [PMID: 22258887 PMCID: PMC5439960 DOI: 10.1007/s10439-012-0510-y] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Accepted: 01/04/2012] [Indexed: 12/23/2022]
Abstract
Polymers provide a versatile platform for mimicking various aspects of physiological extracellular matrix properties such as chemical composition, rigidity, and topography for use in cell and tissue engineering applications. In this review, we provide a brief overview of patterning methods of various polymers with a particular focus on biocompatibility and processability. The materials highlighted here are widely used polymers including thermally curable polydimethyl siloxane, ultraviolet-curable polyurethane acrylate and polyethylene glycol, thermo-sensitive poly(N-isopropylacrylamide) and thermoplastic and conductive polymers. We also discuss how micro- and nanofabricated polymeric substrates of tunable elastic modulus can be used to engineer cell and tissue structure and function. Such synergistic effect of topography and rigidity of polymers may be able to contribute to constructing more physiologically relevant microenvironment.
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Affiliation(s)
- Hong Nam Kim
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Korea
| | - Do-Hyun Kang
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Korea
| | - Min Sung Kim
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Korea
| | - Alex Jiao
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Deok-Ho Kim
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Kahp-Yang Suh
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Korea
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452
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Higuchi A, Ling QD, Hsu ST, Umezawa A. Biomimetic cell culture proteins as extracellular matrices for stem cell differentiation. Chem Rev 2012; 112:4507-40. [PMID: 22621236 DOI: 10.1021/cr3000169] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Akon Higuchi
- Department of Chemical and Materials Engineering, National Central University, Jhongli, Taoyuan, 32001 Taiwan.
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453
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Chen W, Villa-Diaz LG, Sun Y, Weng S, Kim JK, Lam RHW, Han L, Fan R, Krebsbach PH, Fu J. Nanotopography influences adhesion, spreading, and self-renewal of human embryonic stem cells. ACS NANO 2012; 6:4094-103. [PMID: 22486594 PMCID: PMC3358529 DOI: 10.1021/nn3004923] [Citation(s) in RCA: 244] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
Human embryonic stem cells (hESCs) have great potentials for future cell-based therapeutics. However, their mechanosensitivity to biophysical signals from the cellular microenvironment is not well characterized. Here we introduced an effective microfabrication strategy for accurate control and patterning of nanoroughness on glass surfaces. Our results demonstrated that nanotopography could provide a potent regulatory signal over different hESC behaviors, including cell morphology, adhesion, proliferation, clonal expansion, and self-renewal. Our results indicated that topological sensing of hESCs might include feedback regulation involving mechanosensory integrin-mediated cell-matrix adhesion, myosin II, and E-cadherin. Our results also demonstrated that cellular responses to nanotopography were cell-type specific, and as such, we could generate a spatially segregated coculture system for hESCs and NIH/3T3 fibroblasts using patterned nanorough glass surfaces.
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Affiliation(s)
- Weiqiang Chen
- Integrated Biosystems and Biomechanics Laboratory, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Luis G. Villa-Diaz
- Department of Biologic and Materials Sciences, University of Michigan, Ann Arbor, MI 48109, USA
| | - Yubing Sun
- Integrated Biosystems and Biomechanics Laboratory, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Shinuo Weng
- Integrated Biosystems and Biomechanics Laboratory, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jin Koo Kim
- Department of Biologic and Materials Sciences, University of Michigan, Ann Arbor, MI 48109, USA
| | - Raymond H. W. Lam
- Integrated Biosystems and Biomechanics Laboratory, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong
| | - Lin Han
- Department of Biomedical Engineering, Yale University, New Haven, CT 06511, USA
| | - Rong Fan
- Department of Biomedical Engineering, Yale University, New Haven, CT 06511, USA
| | - Paul H. Krebsbach
- Department of Biologic and Materials Sciences, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jianping Fu
- Integrated Biosystems and Biomechanics Laboratory, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
- Correspondence should be addressed to J. Fu [J. Fu (, Tel: 01-734-615-7363, Fax: 01-734-647-7303)]
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454
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Modification of porous calcium phosphate surfaces with different geometries of bioactive glass nanoparticles. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2012. [DOI: 10.1016/j.msec.2012.01.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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455
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Bone biomimetic microenvironment induces osteogenic differentiation of adipose tissue-derived mesenchymal stem cells. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2012; 8:507-15. [DOI: 10.1016/j.nano.2011.07.012] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Accepted: 07/23/2011] [Indexed: 01/21/2023]
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456
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Ilie I, Ilie R, Mocan T, Bartos D, Mocan L. Influence of nanomaterials on stem cell differentiation: designing an appropriate nanobiointerface. Int J Nanomedicine 2012; 7:2211-25. [PMID: 22619557 PMCID: PMC3356220 DOI: 10.2147/ijn.s29975] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
During the last decade, due to advances in functionalization chemistry, novel nanobiomaterials with applications in tissue engineering and regenerative medicine have been developed. These novel materials with their unique physical and chemical properties are bioactive hierarchical structures that hold great promise for future development of human tissues. Thus, various nanomaterials are currently being intensively explored in the directed differentiation of stem cells, the design of novel bioactive scaffolds, and new research avenues towards tissue regeneration. This paper illustrates the latest achievements in the applications of nanotechnology in tissue engineering in the field of regenerative medicine.
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Affiliation(s)
- Ioana Ilie
- Department of Endocrinology, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
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457
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Kulangara K, Yang Y, Yang J, Leong KW. Nanotopography as modulator of human mesenchymal stem cell function. Biomaterials 2012; 33:4998-5003. [PMID: 22516607 DOI: 10.1016/j.biomaterials.2012.03.053] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Accepted: 03/15/2012] [Indexed: 01/21/2023]
Abstract
Nanotopography changes human mesenchymal stem cells (hMSC) from their shape to their differentiation potential; however little is known about the underlying molecular mechanisms. Here we study the culture of hMSC on polydimethylsiloxane substrates with 350 nm grating topography and investigate the focal adhesion composition and dynamics using biochemical and imaging techniques. Our results show that zyxin protein plays a key role in the hMSC response to nanotopography. Zyxin expression is downregulated on 350 nm gratings, leading to smaller and more dynamic focal adhesion. Since the association of zyxin with focal adhesions is force-dependent, smaller zyxin-positive adhesion as well as its higher turnover rate suggests that the traction force in focal adhesion on 350 nm topography is decreased. These changes lead to faster and more directional migration on 350 nm gratings. These findings demonstrate that nanotopography decreases the mechanical forces acting on focal adhesions in hMSC and suggest that force-dependent changes in zyxin protein expression and kinetics underlie the focal adhesion remodeling in response to 350 nm grating topography, resulting in modulation of hMSC function.
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Affiliation(s)
- Karina Kulangara
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
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458
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Kuo SW, Lin HI, Ho JHC, Shih YRV, Chen HF, Yen TJ, Lee OK. Regulation of the fate of human mesenchymal stem cells by mechanical and stereo-topographical cues provided by silicon nanowires. Biomaterials 2012; 33:5013-22. [PMID: 22513273 DOI: 10.1016/j.biomaterials.2012.03.080] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2012] [Accepted: 03/27/2012] [Indexed: 11/30/2022]
Abstract
Extracellular stimuli imposed on stem cells enable efficient initiation of mechanotransductive signaling to regulate stem cell fates; however, how such physical cues conferred by the stereo-topographical matrix govern the fate of stem cells still remains unknown. The purpose of this study is to delineate the effects of stereotopography and its various relevant physical properties on the fate regulation of human mesenchymal stem cells (hMSCs). Stereo-topographical silicon nanowires (SiNWs) that were precisely controlled with respect to their various dimensions and their growth orientation were used in this study. hMSCs cultured on stereo SiNWs of different lengths in the absence of biochemical osteogenic induction cues displayed a spherical and less-elongated morphology and showed an approximately 10% loss of cell viability compared to those grown on two-dimensional (2-D) flat Si. Moreover, osteogenic gene expression of COL1A1 and Runx2 in hMSCs cultured on the shortest SiNWs was significantly higher than those grown on the longer SiNWs and 2-D flat Si. hMSCs grown on shorter SiNWs also demonstrated higher expression levels for F-actin, phosphorylated focal adhesion kinase (pFAK), vinculin and alpha 2 integrin. Stereo-topographical cues provided by SiNWs are able to regulate osteogenic differentiation of hMSCs via cytoskeleton remodeling and this is correlated with the differential expression of alpha 2/beta 1 integrin heterodimers and the focal adhesion molecules pFAK and vinculin. The findings in this study provide insights in terms of the design of stereo-topographical structures for use in tissue engineering, bone regeneration and relevant medical applications.
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Affiliation(s)
- Shu-Wen Kuo
- Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.
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459
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Khanna R, Katti KS, Katti DR. Experiments in Nanomechanical Properties of Live Osteoblast Cells and Cell–Biomaterial Interface. J Nanotechnol Eng Med 2012. [DOI: 10.1115/1.4005666] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Characterizing the mechanical characteristics of living cells and cell–biomaterial composite is an important area of research in bone tissue engineering. In this work, an in situ displacement-controlled nanoindentation technique (using Hysitron Triboscope) is developed to perform nanomechanical characterization of living cells (human osteoblasts) and cell–substrate constructs under physiological conditions (cell culture medium; 37 °C). In situ elastic moduli (E) of adsorbed proteins on tissue culture polystyrene (TCPS) under cell culture media were found to be ∼4 GPa as revealed by modulus mapping experiments. The TCPS substrates soaked in cell culture medium showed significant difference in surface nanomechanical properties (up to depths of ∼12 nm) as compared to properties obtained from deeper indentations. Atomic force microscopy (AFM) revealed the cytoskeleton structures such as actin stress fiber networks on flat cells which are believed to impart the structural integrity to cell structure. Load-deformation response of cell was found to be purely elastic in nature, i.e., cell recovers its shape on unloading as indicated by linear loading and unloading curves obtained at 1000 nm indentation depth. The elastic response of cells is obtained during initial cell adhesion (ECell, 1 h, 1000 nm = 4.4–12.4 MPa), cell division (ECell, 2 days, 1000 nm = 1.3–3.0 MPa), and cell spreading (ECell, 2 days, 1000 nm = 6.9–11.6 MPa). Composite nanomechanical responses of cell–TCPS constructs were obtained by indentation at depths of 2000 nm and 3000 nm on cell-seeded TCPS. Elastic properties of cell–substrate composites were mostly dominated by stiff TCPS (EBulk = 5 GPa) lying underneath the cell.
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Affiliation(s)
- Rohit Khanna
- Department of Civil Engineering, North Dakota State University, Fargo, ND 58105
| | - Kalpana S. Katti
- Department of Civil Engineering, North Dakota State University, Fargo, ND 58105
| | - Dinesh R. Katti
- Department of Civil Engineering, North Dakota State University, Fargo, ND 58105
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460
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Brammer KS, Frandsen CJ, Jin S. TiO2 nanotubes for bone regeneration. Trends Biotechnol 2012; 30:315-22. [PMID: 22424819 DOI: 10.1016/j.tibtech.2012.02.005] [Citation(s) in RCA: 166] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Revised: 02/14/2012] [Accepted: 02/15/2012] [Indexed: 01/09/2023]
Abstract
Nanostructured materials are believed to play a fundamental role in orthopedic research because bone itself has a structural hierarchy at the first level in the nanometer regime. Here, we report on titanium oxide (TiO(2)) surface nanostructures utilized for orthopedic implant considerations. Specifically, the effects of TiO(2) nanotube surfaces for bone regeneration will be discussed. This unique 3D tube shaped nanostructure created by electrochemical anodization has profound effects on osteogenic cells and is stimulating new avenues for orthopedic material surface designs. There is a growing body of data elucidating the benefits of using TiO(2) nanotubes for enhanced orthopedic implant surfaces. The current trends discussed within foreshadow the great potential of TiO(2) nanotubes for clinical use.
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Affiliation(s)
- Karla S Brammer
- Materials Science and Engineering, University of California, San Diego, La Jolla, CA 92093-0411, USA
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461
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Ruiz JP, Pelaez D, Dias J, Ziebarth NM, Cheung HS. The effect of nicotine on the mechanical properties of mesenchymal stem cells. ACTA ACUST UNITED AC 2012; 4:29-35. [PMID: 23060733 DOI: 10.2147/chc.s24381] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
PURPOSE: To measure the elasticity of the nucleus and cytoplasm of human mesenchymal stem cells (MSCs) as well as changes brought about by exposure to nicotine in vitro. METHODS: MSCs were synchronized to the G(0) stage of the cell cycle through serum deprivation techniques. The cells were then treated with medium containing nicotine (0.1 µM, 0.5 µM, and 1 µM). Atomic force microscopy was then used to measure the Young's modulus of both the nucleus and cytoplasm of these cells. RESULTS: For both unsynchronized and synchronized cells, the nucleus was softer than the cytoplasm, although this difference was not found to be statistically significant. The nucleus of cells treated with nicotine was significantly stiffer than the control for all concentrations. The cytoplasm was significantly stiffer in nicotine-treated cells than in control cells for the 0.5 µM and 1.0 µM concentrations only. CONCLUSIONS: The results of this study could suggest that nicotine affects the biophysical properties of human MSCs in a dose-dependent manner, which may render the cells less responsive to mechanoinduction and other physical stimuli.
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Affiliation(s)
- Juan P Ruiz
- Department of Biomedical Engineering, University of Miami College of Engineering, Coral Gables, FL, USA ; Research Service and Geriatrics Research, Education, and Clinical Center, Veterans Affairs Medical Center, Miami, FL, USA
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462
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Sun Y, Chen CS, Fu J. Forcing stem cells to behave: a biophysical perspective of the cellular microenvironment. Annu Rev Biophys 2012; 41:519-42. [PMID: 22404680 DOI: 10.1146/annurev-biophys-042910-155306] [Citation(s) in RCA: 297] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Physical factors in the local cellular microenvironment, including cell shape and geometry, matrix mechanics, external mechanical forces, and nanotopographical features of the extracellular matrix, can all have strong influences on regulating stem cell fate. Stem cells sense and respond to these insoluble biophysical signals through integrin-mediated adhesions and the force balance between intracellular cytoskeletal contractility and the resistant forces originated from the extracellular matrix. Importantly, these mechanotransduction processes can couple with many other potent growth-factor-mediated signaling pathways to regulate stem cell fate. Different bioengineering tools and microscale/nanoscale devices have been successfully developed to engineer the physical aspects of the cellular microenvironment for stem cells, and these tools and devices have proven extremely powerful for identifying the extrinsic physical factors and their downstream intracellular signaling pathways that control stem cell functions.
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Affiliation(s)
- Yubing Sun
- Integrated Biosystems and Biomechanics Laboratory, Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
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463
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Engineering airway epithelium. J Biomed Biotechnol 2012; 2012:982971. [PMID: 22523471 PMCID: PMC3304574 DOI: 10.1155/2012/982971] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Revised: 10/28/2011] [Accepted: 10/30/2011] [Indexed: 12/11/2022] Open
Abstract
Airway epithelium is constantly presented with injurious signals, yet under healthy circumstances, the epithelium maintains its innate immune barrier and mucociliary elevator function. This suggests that airway epithelium has regenerative potential (I. R. Telford and C. F. Bridgman, 1990). In practice, however, airway regeneration is problematic because of slow turnover and dedifferentiation of epithelium thereby hindering regeneration and increasing time necessary for full maturation and function. Based on the anatomy and biology of the airway epithelium, a variety of tissue engineering tools available could be utilized to overcome the barriers currently seen in airway epithelial generation. This paper describes the structure, function, and repair mechanisms in native epithelium and highlights specific and manipulatable tissue engineering signals that could be of great use in the creation of artificial airway epithelium.
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464
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Deng M, James R, Laurencin CT, Kumbar SG. Nanostructured polymeric scaffolds for orthopaedic regenerative engineering. IEEE Trans Nanobioscience 2012; 11:3-14. [PMID: 22275722 DOI: 10.1109/tnb.2011.2179554] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Successful regeneration necessitates the development of three-dimensional (3-D) tissue-inducing scaffolds that mimic the hierarchical architecture of native tissue extracellular matrix (ECM). Cells in nature recognize and interact with the surface topography they are exposed to via ECM proteins. The interaction of cells with nanotopographical features such as pores, ridges, groves, fibers, nodes, and their combinations has proven to be an important signaling modality in controlling cellular processes. Integrating nanotopographical cues is especially important in engineering complex tissues that have multiple cell types and require precisely defined cell-cell and cell-matrix interactions on the nanoscale. Thus, in a regenerative engineering approach, nanoscale materials/scaffolds play a paramount role in controlling cell fate and the consequent regenerative capacity. Advances in nanotechnology have generated a new toolbox for the fabrication of tissue-specific nanostructured scaffolds. For example, biodegradable polymers such as polyesters, polyphosphazenes, polymer blends and composites can be electrospun into ECM-mimicking matrices composed of nanofibers, which provide high surface area for cell attachment, growth, and differentiation. This review provides the fundamental guidelines for the design and development of nanostructured scaffolds for the regeneration of various tissue types in human upper and lower extremities such as skin, ligament, tendon, and bone. Examples focusing on the collective work of our laboratory in those areas are discussed to demonstrate the regenerative efficacy of this approach. Furthermore, preliminary strategies and significant challenges to integrate these individual tissues into one complex organ through regenerative engineering-based integrated graft systems are also discussed.
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Affiliation(s)
- Meng Deng
- Institute for Regenerative Engineering and Departmentof Orthopaedic Surgery at the University of Connecticut Health Center, Farmington, CT 06030, USA
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465
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Frith JE, Mills RJ, Cooper-White JJ. Lateral spacing of adhesion peptides influences human mesenchymal stem cell behaviour. J Cell Sci 2012; 125:317-27. [DOI: 10.1242/jcs.087916] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mesenchymal stem cells (MSCs) have attracted great interest in recent years for tissue engineering and regenerative medicine applications due to their ease of isolation and multipotent differentiation capacity. In the past, MSC research has focussed on the effects of soluble cues, such as growth factors and cytokines; however, there is now increasing interest in understanding how parameters such as substrate modulus, specific extracellular matrix (ECM) components and the ways in which these are presented to the cell can influence MSC properties. Here we use surfaces of self-assembled maleimide-functionalized polystyrene-block-poly(ethylene oxide) copolymers (PS-PEO-Ma) to investigate how the spatial arrangement of cell adhesion ligands affects MSC behaviour. By changing the ratio of PS-PEO-Ma in mixtures of block copolymer and polystyrene homopolymer, we can create surfaces with lateral spacing of the PEO-Ma domains ranging from 34 to 62 nm. Through subsequent binding of cysteine–GRGDS peptides to the maleimide-terminated end of the PEO chains in each of these domains, we are able to present tailored surfaces of controlled lateral spacing of RGD (arginine-glycine-aspartic acid) peptides to MSCs. We demonstrate that adhesion of MSCs to the RGD-functionalized block-copolymer surfaces is through specific attachment to the presented RGD motif and that this is mediated by α5, αV, β1 and β3 integrins. We show that as the lateral spacing of the peptides is increased, the ability of the MSCs to spread is diminished and that the morphology changes from well-spread cells with normal fibroblastic morphology and defined stress-fibres, to less-spread cells with numerous cell protrusions and few stress fibres. In addition, the ability of MSCs to form mature focal adhesions is reduced on substrates with increased lateral spacing. Finally, we investigate differentiation and use qRT-PCR determination of gene expression levels and a quantitative alkaline phosphatase assay to show that MSC osteogenesis is reduced on surfaces with increased lateral spacing while adipogenic differentiation is increased. We show here, for the first time, that the lateral spacing of adhesion peptides affects human MSC (hMSC) properties and might therefore be a useful parameter with which to modify hMSC behaviour in future tissue engineering strategies.
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Affiliation(s)
- Jessica E. Frith
- Tissue Engineering and Microfluidics Laboratory, Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Queensland, 4072, Australia
| | - Richard J. Mills
- Tissue Engineering and Microfluidics Laboratory, Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Queensland, 4072, Australia
| | - Justin J. Cooper-White
- Tissue Engineering and Microfluidics Laboratory, Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Queensland, 4072, Australia
- School of Chemical Engineering, University of Queensland, Queensland, 4072, Australia
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466
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Wang PY, Clements LR, Thissen H, Hung SC, Cheng NC, Tsai WB, Voelcker NH. Screening the attachment and spreading of bone marrow-derived and adipose-derived mesenchymal stem cells on porous silicon gradients. RSC Adv 2012. [DOI: 10.1039/c2ra21557h] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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467
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Chen A, Lieu DK, Freschauf L, Lew V, Sharma H, Wang J, Nguyen D, Karakikes I, Hajjar RJ, Gopinathan A, Botvinick E, Fowlkes CC, Li RA, Khine M. Shrink-film configurable multiscale wrinkles for functional alignment of human embryonic stem cells and their cardiac derivatives. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2011; 23:5785-91. [PMID: 22065428 DOI: 10.1002/adma.201103463] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Indexed: 05/04/2023]
Abstract
A biomimetic substrate for cell-culture is fabricated by plasma treatment of a prestressed thermoplastic shrink film to create tunable multiscaled alignment "wrinkles". Using this substrate, the functional alignment of human embryonic stem cell derived cardiomyocytes is demonstrated.
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Affiliation(s)
- Aaron Chen
- Department of Chemical Engineering and Material Science, University of California, Irvine, 92697, USA
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468
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Teo BK, Goh SH, Kustandi TS, Loh WW, Low HY, Yim EK. The effect of micro and nanotopography on endocytosis in drug and gene delivery systems. Biomaterials 2011; 32:9866-75. [DOI: 10.1016/j.biomaterials.2011.08.088] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 08/31/2011] [Indexed: 10/17/2022]
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469
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Peng R, Yao X, Ding J. Effect of cell anisotropy on differentiation of stem cells on micropatterned surfaces through the controlled single cell adhesion. Biomaterials 2011; 32:8048-57. [DOI: 10.1016/j.biomaterials.2011.07.035] [Citation(s) in RCA: 219] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Accepted: 07/11/2011] [Indexed: 10/17/2022]
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470
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McKee CT, Raghunathan VK, Nealey PF, Russell P, Murphy CJ. Topographic modulation of the orientation and shape of cell nuclei and their influence on the measured elastic modulus of epithelial cells. Biophys J 2011; 101:2139-46. [PMID: 22067151 DOI: 10.1016/j.bpj.2011.09.042] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Revised: 08/25/2011] [Accepted: 09/26/2011] [Indexed: 01/08/2023] Open
Abstract
The influence of nucleus shape and orientation on the elastic modulus of epithelial cells was investigated with atomic force microscopy. The shape and orientation were controlled by presenting the epithelial cells with anisotropic parallel ridges and grooves of varying pitch at the cell substratum. As the cells oriented to the underlying topography, the volume of the nucleus increased as the pitch of the topography increased from 400 nm to 2000 nm. The increase in nucleus volume was reflected by an increase in the measured elastic modulus of the topographically aligned cells. Significant alterations in the shape of the nucleus, by intimate contact with the topographic ridge and grooves of the underlying cell, were also observed via confocal microscopy, indicating that the nucleus may also act as a direct mechanosensor of substratum topography.
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Affiliation(s)
- Clayton T McKee
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, California, USA
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471
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Control of adhesion, focal adhesion assembly, and differentiation of myoblasts by enzymatically crosslinked cell-interactive hydrogels. Macromol Res 2011. [DOI: 10.1007/s13233-011-0909-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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472
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Li H, LaBean TH, Leong KW. Nucleic acid-based nanoengineering: novel structures for biomedical applications. Interface Focus 2011; 1:702-24. [PMID: 23050076 PMCID: PMC3262286 DOI: 10.1098/rsfs.2011.0040] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Accepted: 06/01/2011] [Indexed: 01/21/2023] Open
Abstract
Nanoengineering exploits the interactions of materials at the nanometre scale to create functional nanostructures. It relies on the precise organization of nanomaterials to achieve unique functionality. There are no interactions more elegant than those governing nucleic acids via Watson-Crick base-pairing rules. The infinite combinations of DNA/RNA base pairs and their remarkable molecular recognition capability can give rise to interesting nanostructures that are only limited by our imagination. Over the past years, creative assembly of nucleic acids has fashioned a plethora of two-dimensional and three-dimensional nanostructures with precisely controlled size, shape and spatial functionalization. These nanostructures have been precisely patterned with molecules, proteins and gold nanoparticles for the observation of chemical reactions at the single molecule level, activation of enzymatic cascade and novel modality of photonic detection, respectively. Recently, they have also been engineered to encapsulate and release bioactive agents in a stimulus-responsive manner for therapeutic applications. The future of nucleic acid-based nanoengineering is bright and exciting. In this review, we will discuss the strategies to control the assembly of nucleic acids and highlight the recent efforts to build functional nucleic acid nanodevices for nanomedicine.
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Affiliation(s)
| | | | - Kam W. Leong
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, PO Box 90281, Durham, NC 27708, USA
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473
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Namgung S, Baik KY, Park J, Hong S. Controlling the growth and differentiation of human mesenchymal stem cells by the arrangement of individual carbon nanotubes. ACS NANO 2011; 5:7383-90. [PMID: 21819114 DOI: 10.1021/nn2023057] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Carbon nanotube (CNT) networks on solid substrates have recently drawn attention as a means to direct the growth and differentiation of stem cells. However, it is still not clear whether cells can recognize individual CNTs with a sub-2 nm diameter, and directional nanostructured substrates such as aligned CNT networks have not been utilized to control cell behaviors. Herein, we report that human mesenchymal stem cells (hMSCs) grown on CNT networks could recognize the arrangement of individual CNTs in the CNT networks, which allowed us to control the growth direction and differentiation of the hMSCs. We achieved the directional growth of hMSCs following the alignment direction of the individual CNTs. Furthermore, hMSCs on aligned CNT networks exhibited enhanced proliferation and osteogenic differentiation compared to those on randomly oriented CNT networks. As a plausible explanation for the enhanced proliferation and osteogenic differentiation, we proposed mechanotransduction pathways triggered by high cytoskeletal tension in the aligned hMSCs. Our findings provide new insights regarding the capability of cells to recognize nanostructures smaller than proteins and indicate their potential applications for regenerative tissue engineering.
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Affiliation(s)
- Seon Namgung
- Department of Physics and Astronomy, Seoul National University, Seoul, 151-747, Korea
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474
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Seo CH, Furukawa K, Montagne K, Jeong H, Ushida T. The effect of substrate microtopography on focal adhesion maturation and actin organization via the RhoA/ROCK pathway. Biomaterials 2011; 32:9568-75. [PMID: 21925729 DOI: 10.1016/j.biomaterials.2011.08.077] [Citation(s) in RCA: 136] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Accepted: 08/26/2011] [Indexed: 02/02/2023]
Abstract
Recently, a growing number of reports have reported that micro- or nanoscale topography enhances cellular functions such as cell adhesion and stem cell differentiation, but the mechanisms responsible for this topography-mediated cell behavior are not fully understood. In this study, we examine the underlying processes and mechanisms behind specific topography-mediated cellular functions. Formation of focal adhesions (FA) was studied by culturing cells on different kinds of topographies, including a flat surface and surfaces with a micropatterned topography (2 μm lattice pattern with 3 μm intervals). We found that the formation and maturation of focal adhesions were highly dependent on the topography of the substrate although the shape, morphology and spreading of cells on the different substrates were not significantly affected. Focal adhesion maturation and actin polymerization were also promoted in cells cultured on the micropatterned substrate. These differences in cell adhesion led us to focus on the Rho GTPases, RhoA and downstream pathways since a number of reports have demonstrated that RhoA-activated cells have highly enhanced focal adhesions and actin activation such as polymerization. By inhibiting the Rho-associated kinase (ROCK) and downstream myosin II, we found that the FA formation, actin organization, and FAK phosphorylation were dramatically decreased. The topographical dependency of FA formation was also highly decreased. These results show that the FA formation and actin cytoskeleton organization of cells on the microtopography is regulated by the RhoA/ROCK pathway.
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Affiliation(s)
- Chang Ho Seo
- Department of Bioengineering, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-gu, Tokyo 113-8656, Japan
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475
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Wang Y, Jiang XL, Yang SC, Lin X, He Y, Yan C, Wu L, Chen GQ, Wang ZY, Wu Q. MicroRNAs in the regulation of interfacial behaviors of MSCs cultured on microgrooved surface pattern. Biomaterials 2011; 32:9207-17. [PMID: 21890196 DOI: 10.1016/j.biomaterials.2011.08.058] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Accepted: 08/18/2011] [Indexed: 12/21/2022]
Abstract
Cell-substrate interaction is one of the most important aspects of tissue engineering. Changes of MSCs interfacial behaviors were found to be triggered by 10 μm wide grooved pattern on poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx). Global marker genes expression and miRNAs profiling analysis provided insights into the regulation network of the topography induced MSCs' cell responses including adhesion, proliferation, differentiation and apoptosis. Compared to MSCs cultured on the smooth substrates, MSCs incubated on microgrooved PHBHHx substrates showed increased expression of osteogenesis-related marker genes including cbfa1, col1a1 and bmp2, and decreased expression of vcl, vinculin encoding gene, adipogenesis-related genes including lpl, des and acta2, as well as myogenesis-related genes of myh11 and nse. The miRNA microarrays revealed that 18 differentially-expressed miRNAs on microgrooved pattern had multiple target genes, contributing comprehensively to the cellular regulation process. Similar to the topography-triggered ostegenenesis, co-transfection of the osteogenic miRNAs combination (miR-140, miR-214, miR-320, miR-351 and miR-674-5p) was able to stimulate the expression of osteogenic marker genes. This study elucidated the important roles of miRNAs in the regulation processes of the microenvironment triggered cell behaviors, and provided clues for the PHA biomedical materials development.
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Affiliation(s)
- Yang Wang
- Ministry of Education Key Laboratory of Bioinformatics, Department of Biological Sciences and Biotechnology, School of Life Sciences, Tsinghua University, Beijing 100084, China
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476
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Le DM, Kulangara K, Adler AF, Leong KW, Ashby VS. Dynamic topographical control of mesenchymal stem cells by culture on responsive poly(ε-caprolactone) surfaces. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2011; 23:3278-83. [PMID: 21626577 PMCID: PMC3972817 DOI: 10.1002/adma.201100821] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 04/22/2011] [Indexed: 05/21/2023]
Affiliation(s)
- Duy M. Le
- Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599 (USA)
| | - Karina Kulangara
- Department of Biomedical Engineering, Duke University, Durham, NC 27710 (USA)
| | - Andrew F. Adler
- Department of Biomedical Engineering, Duke University, Durham, NC 27710 (USA)
| | - Kam W. Leong
- Department of Biomedical Engineering, Duke University, Durham, NC 27710 (USA)
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477
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Nguyen LTH, Liao S, Ramakrishna S, Chan CK. The role of nanofibrous structure in osteogenic differentiation of human mesenchymal stem cells with serial passage. Nanomedicine (Lond) 2011; 6:961-74. [DOI: 10.2217/nnm.11.26] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Using scaffolds with autologous stem cells is a golden strategy for the treatment of bone defects. In this strategy, human mesenchymal stem cells (hMSCs) have often been isolated and expanded in vitro on a plastic surface to obtain a sufficient cell number before seeding on a suitable scaffold. Materials & Methods: Investigating the influence of serial passages (from passage two to passage eight) on the abilities of proliferation and osteogenic differentiation of hMSCs on 24-well tissue culture polystyrene plates and poly L-lactic acid electrospun nanofibrous scaffolds was performed to determine how prolonged culture affected these cellular abilities and how the nanofibrous scaffolds supported the osteogenic differentiation potential of hMSCs. Results & Conclusion: Serial passage caused adverse changes in hMSCs characteristics, which were indicated by the decline in both proliferation and osteogenic differentiation abilities. Interestingly, the poly L-lactic acid nanofibrous scaffolds showed a significant support in recovering the osteogenic abilities of hMSCs, which had been severely affected by prolonged culture.
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Affiliation(s)
| | - Susan Liao
- Nanyang Technological University, 637551 Singapore
| | - Seeram Ramakrishna
- National University of Singapore, 117576 Singapore
- Institute of Materials Research & Engineering, 117602 Singapore
| | - Casey K Chan
- National University of Singapore, 117576 Singapore
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478
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Tchemtchoua VT, Atanasova G, Aqil A, Filée P, Garbacki N, Vanhooteghem O, Deroanne C, Noël A, Jérome C, Nusgens B, Poumay Y, Colige A. Development of a chitosan nanofibrillar scaffold for skin repair and regeneration. Biomacromolecules 2011; 12:3194-204. [PMID: 21761871 DOI: 10.1021/bm200680q] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The final goal of the present study was the development of a 3-D chitosan dressing that would shorten the healing time of skin wounds by stimulating migration, invasion, and proliferation of the relevant cutaneous resident cells. Three-dimensional chitosan nanofibrillar scaffolds produced by electrospinning were compared with evaporated films and freeze-dried sponges for their biological properties. The nanofibrillar structure strongly improved cell adhesion and proliferation in vitro. When implanted in mice, the nanofibrillar scaffold was colonized by mesenchymal cells and blood vessels. Accumulation of collagen fibrils was also observed. In contrast, sponges induced a foreign body granuloma. When used as a dressing covering full-thickness skin wounds in mice, chitosan nanofibrils induced a faster regeneration of both the epidermis and dermis compartments. Altogether our data illustrate the critical importance of the nanofibrillar structure of chitosan devices for their full biocompatibility and demonstrate the significant beneficial effect of chitosan as a wound-healing biomaterial.
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479
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Lee H, Jang Y, Seo J, Nam JM, Char K. Nanoparticle-functionalized polymer platform for controlling metastatic cancer cell adhesion, shape, and motility. ACS NANO 2011; 5:5444-5456. [PMID: 21702475 DOI: 10.1021/nn202103z] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Controlling and understanding the changes in metastatic cancer cell adhesion, shape, and motility are of paramount importance in cancer research, diagnosis, and treatment. Here, we used gold nanoparticles (AuNPs) as nanotopological structures and protein nanocluster forming substrates. Cell adhesion controlling proteins [in this case, fibronection (Fn) and ephrinB3] were modified to AuNPs, and these particles were then modified to the layer-by-layer (LbL) polymer surface that offers a handle for tuning surface charge and mechanical property of a cell-interfacing substrate. We found that metastatic cancer cell adhesion is affected by nanoparticle density on a surface, and ∼140 particles per 400 μm(2) (∼1.7 μm spacing between AuNPs) is optimal for effective metastatic cell adhesion. It was also shown that the AuNP surface density and protein nanoclustering on a spherical AuNP are controlling factors for the efficient interfacing and signaling of metastatic cancer cells. Importantly, the existence of nanotopological features (AuNPs in this case) is much more critical in inducing more dramatic changes in metastatic cell adhesion, protrusion, polarity, and motility than the presence of a cell adhesion protein, Fn, on the surface. Moreover, cell focal adhesion and motility-related paxillin clusters were heavily formed in cell lamellipodia and filopodia and high expression of phospho-paxillins were observed when the cells were cultured on either an AuNP or Fn-modified AuNP polymer surface. The ephrin signaling that results in the decreased expression of paxillin was found to be more effective when ephrins were modified to the AuNP surface than when ephrinB3 was directly attached to the polymer film. The overall trend for cell motility change is such that a nanoparticle-modified LbL surface induces higher cell motility and the AuNP modification to the LbL surface results in more pronounced change in cell motility than Fn or ephrin modification to the LbL surface.
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Affiliation(s)
- Hyojin Lee
- Department of Chemistry, Seoul National University, Seoul, 151-747, Korea
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480
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Lee JW, Lee KB, Jeon HS, Park HK. Effects of surface nano-topography on human osteoblast filopodia. ANAL SCI 2011; 27:369. [PMID: 21478611 DOI: 10.2116/analsci.27.369] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Anchorage-dependent cells growing over a substratum require stable adhesion areas on the surface for the next cellular activities. The adhesion is achieved by some contact points called focal adhesions. Because focal adhesions were distributed randomly, a trial to control the positions of focal adhesion with a specific order may cause interesting effects like as cytoskeleton rearrangement, which may induce and transfer new signals to the nucleus. Here, we cultured human osteoblasts over two sorts of nanopatterned surfaces with different pattern densities fabricated by using laser interference lithography and the nanoimprinting technique. Of the two nanopatterns, cells over the nanopattern with low pattern density showed relatively higher adaptation to the topography with guided filopodia protrusion. However, cells over the dense nanopattern showed difficulty in finding suitable paths for migration, as judged from the activities of filopodium formation and the presence of a shovel-like feature at the tip of each filopodium.
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Affiliation(s)
- Jin-Woo Lee
- Department of Biomedical Engineering, College of Medicine, Kyunghee University, Hoegi, Seongbuk, Seoul, Korea
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481
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Koo S, Ahn SJ, Zhang H, Wang JC, Yim EKF. Human Corneal Keratocyte Response to Micro- and Nano-Gratings on Chitosan and PDMS. Cell Mol Bioeng 2011. [DOI: 10.1007/s12195-011-0186-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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482
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Palmquist A, Johansson A, Suska F, Brånemark R, Thomsen P. Acute Inflammatory Response to Laser‐Induced Micro‐ and Nano‐Sized Titanium Surface Features. Clin Implant Dent Relat Res 2011; 15:96-104. [DOI: 10.1111/j.1708-8208.2011.00361.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Anders Palmquist
- Researcher, Department of Biomaterials, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - Anna Johansson
- biomedical scientist, Department of Biomaterials, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - Felicia Suska
- research, Department of Biomaterials, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - Rickard Brånemark
- orthopaedic surgeon, Department of Orthopaedics, Sahlgrenska University Hospital, Göteborg, Sweden
| | - Peter Thomsen
- professor, Department of Biomaterials, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden, and Institute of Biomaterials and Cell Therapy, Göteborg, Sweden
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483
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Pennisi CP, Dolatshahi-Pirouz A, Foss M, Chevallier J, Fink T, Zachar V, Besenbacher F, Yoshida K. Nanoscale topography reduces fibroblast growth, focal adhesion size and migration-related gene expression on platinum surfaces. Colloids Surf B Biointerfaces 2011; 85:189-97. [DOI: 10.1016/j.colsurfb.2011.02.028] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2010] [Revised: 02/21/2011] [Accepted: 02/21/2011] [Indexed: 12/13/2022]
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484
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Curran J, Pu F, Chen R, Hunt J. The use of dynamic surface chemistries to control msc isolation and function. Biomaterials 2011; 32:4753-60. [DOI: 10.1016/j.biomaterials.2011.03.045] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Accepted: 03/19/2011] [Indexed: 01/28/2023]
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485
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Migliorini E, Grenci G, Ban J, Pozzato A, Tormen M, Lazzarino M, Torre V, Ruaro ME. Acceleration of neuronal precursors differentiation induced by substrate nanotopography. Biotechnol Bioeng 2011; 108:2736-46. [PMID: 21656711 DOI: 10.1002/bit.23232] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Revised: 05/13/2011] [Accepted: 05/23/2011] [Indexed: 01/16/2023]
Abstract
Embryonic stem (ES) cell differentiation in specific cell lineages is a major issue in cell biology particularly in regenerative medicine. Differentiation is usually achieved by using biochemical factors and it is not clear whether mechanical properties of the substrate over which cells are grown can affect proliferation and differentiation. Therefore, we produced patterns in polydimethylsiloxane (PDMS) consisting of groove and pillar arrays of sub-micrometric lateral resolution as substrates for cell cultures. We analyzed the effect of different nanostructures on differentiation of ES-derived neuronal precursors into neuronal lineage without adding biochemical factors. Neuronal precursors adhered on PDMS more effectively than on glass coverslips. We demonstrated that neuronal yield was enhanced by increasing pillars height from 35 to 400 nm. On higher pillar neuronal differentiation reaches ∼80% 96 h after plating and the largest differentiation enhancement of pillars over flat PDMS was observed during the first 6 h of culture. We conclude that PDMS nanopillars accelerate and increase neuronal differentiation.
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Affiliation(s)
- Elisa Migliorini
- CNR-IOM Laboratorio TASC, Area Science Park, Basovizza, 34149 Trieste, Italy
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486
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Analysis on migration and activation of live macrophages on transparent flat and nanostructured titanium. Acta Biomater 2011; 7:2337-44. [PMID: 21232636 DOI: 10.1016/j.actbio.2011.01.006] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 12/24/2010] [Accepted: 01/06/2011] [Indexed: 01/10/2023]
Abstract
The immunotoxicity of implanted nanostructured titanium is a paramount issue for vascular, dental and orthopedic applications. However, it has been unclear whether implanted surface nanostructures can inhibit or aggrevate inflammatory responses. Herein, macrophage activation, as evidence of migration, on transparent flat and nanostructured titanium correlated with pro-inflammatory protein synthesis and cytokine release. Through the real-time monitoring of initial cytoskeleton variations, this study identified that macrophage movement was restricted on nanostructured titanium compared to flat titanium surfaces. Furthermore, nanostructured titanium elicited secretion of fewer pro-inflammatory enzyme molecules and cytokines, as well as reduced nitric oxide production. All results collectively indicated that initial macrophage activation can be mitigated by nanoscale surface topography alone, without modification of surface chemistry or stiffness.
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487
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Subramanian G, Picu CR. Mechanics of three-dimensional, nonbonded random fiber networks. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 83:056120. [PMID: 21728618 DOI: 10.1103/physreve.83.056120] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Indexed: 05/31/2023]
Abstract
The mechanical behavior of an ensemble of athermal fibers forming a nonbonded network subjected to triaxial compression is studied using a numerical model. The response exhibits a power law dependence of stress on the dilatation strain and hysteresis upon loading and unloading. A stable hysteresis loop results after the first loading and unloading cycle. In the early stages of compaction, strain energy is associated primarily with the bending of fibers, while at higher densities, it is stored primarily in the axial deformation mode. It is shown that the exponent of the power law, and the partition of energy in the axial and bending modes depends on the ratio of the bending to axial stiffness of the fibers. Accounting for interfiber friction does not change the functional form of the stress-strain relationship or the exponent. The central feature that distinguishes the mechanics of this system from that of bonded random networks is the relative sliding at contacts and the ensuing fiber rearrangements. We show that suppressing sliding leads to a much stiffer response. The results indicate that the value of the exponent of the stress-strain power law is determined not only by fiber bending and the formation of new contacts, but also by the relative sliding and axial deformation of fibers.
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Affiliation(s)
- Gopinath Subramanian
- Scientific Computation Research Center, Rensselaer Polytechnic Institute, Troy, New York 12180-3590, USA
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488
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Lu Z, Roohani-Esfahani SI, Kwok PCL, Zreiqat H. Osteoblasts on rod shaped hydroxyapatite nanoparticles incorporated PCL film provide an optimal osteogenic niche for stem cell differentiation. Tissue Eng Part A 2011; 17:1651-61. [PMID: 21306280 DOI: 10.1089/ten.tea.2010.0567] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
After the clinical insertion of a bone biomaterial, the surrounding osteoblasts would migrate and attach to the implant surface and foster a microenvironment that largely determines the differentiation fate of the comigrated mesenchymal stem cells. Whether the fostered microenvironment is suitable for osteogenic differentiation of mesenchymal stem cells is critical for the subsequent osseointegration. In this study, we determined (1) how the spherical or rod-shaped hydroxyapatite nanoparticles (nHA) incorporated poly(ɛ-caprolactone) (PCL) films (PCL-spherical nHA, PCL-rod nHA) interact with primary human osteoblasts (HOBs); (2) how the microenvironment rendered by their interaction affects osteogenic differentiation of adipose tissue-derived mesenchymal stem cells (ASCs). HOBs were seeded on PCL, PCL-spherical nHA, and PCL-rod nHA films, respectively. When cultured alone, the HOBs on PCL-rod nHA films showed most efficient osteoblastic differentiation compared with those on PCL or PCL-spherical nHA films. When cocultured with ASCs in an indirect coculture system, only the HOBs on PCL-rod nHA films up-regulated the gene expression of Runx2, bone sialoprotein, and osteocalcin of ASCs. Additionally, the HOBs on PCL-rod nHA films showed significant up-regulation of bone morphogenic protein 2 gene and protein expression and induced highest phosphorylated Smad1/5 protein level in ASCs. Treatment of the coculture medium with bone morphogenic protein 2 inhibitor (Noggin) largely abolished the osteogenic differentiation of the ASCs induced by the HOBs on PCL-rod nHA films. In conclusion, HOBs can not only best display their osteoblastic phenotype by culturing on PCL-rod nHA films but also render an optimal osteogenic niche for the differentiation of stem cells.
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Affiliation(s)
- ZuFu Lu
- Biomaterials and Tissue Engineering Research Unit, School of AMME, The University of Sydney, Sydney, Australia
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489
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Wang G, Zheng L, Zhao H, Miao J, Sun C, Ren N, Wang J, Liu H, Tao X. In vitro assessment of the differentiation potential of bone marrow-derived mesenchymal stem cells on genipin-chitosan conjugation scaffold with surface hydroxyapatite nanostructure for bone tissue engineering. Tissue Eng Part A 2011; 17:1341-9. [PMID: 21247339 DOI: 10.1089/ten.tea.2010.0497] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Increasing evidence has revealed that the surface characteristics of biomaterials, such as chemical composition, stiffness, and topography, especially nanotopography, significantly influence cell growth and differentiation. In this study, we examined the effect of surface biomimetic apatite nanostructure of a new hydroxyapatite-coated genipin-chitosan conjugation scaffold (HGCCS) on cell shape, cytoskeleton organization, and osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells in vitro. Cell shape and cytoskeleton organization showed significant differences between cells cultured on genipin-cross-linked chitosan framework and those cultured on HGCCS with surface apatite network-like nanostructure after 7 days of incubation in the osteogenic medium. The result of specific alkaline phosphatase activity as an indicator of osteogenic differentiation showed that the alkaline phosphatase activity of rat bone marrow-derived mesenchymal stem cells was higher on HGCCS. Based on quantitative real-time polymerase chain reaction, HGCCS induced highest mRNA expression of osteogenic differentiation makers, runt-related transcription factor 2 by 7 days, osteopontin by 7 days, and osteocalcin by 14 days, respectively. The enhanced ability of cells on HGCCS to produce mineralized extracellular matrix and nodules was also assessed on day 14 with Alizarin red staining. The results of this study suggest that the surface biomimetic apatite nanostructure of HGCCS is a critical signal cue to promoting osteogenic differentiation in vitro. These findings open a new research avenue to controlling stem cell lineage commitment and provide a promising scaffold for bone tissue engineering.
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Affiliation(s)
- Guancong Wang
- Center of Bio & Micro/Nano Functional Materials, State Key Laboratory of Crystal Materials, Shandong University, Jinan, PR China
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490
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Yan C, Sun J, Ding J. Critical areas of cell adhesion on micropatterned surfaces. Biomaterials 2011; 32:3931-8. [PMID: 21356556 DOI: 10.1016/j.biomaterials.2011.01.078] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Accepted: 01/19/2011] [Indexed: 12/20/2022]
Abstract
The adhesive area is important to modulate cell behaviors on a substrate. This paper aims to semi-quantitatively examine the existence of the characteristic areas of cell adhesion on the level of individual cells. We prepared a series of micropatterned surfaces with adhesive microislands of various sizes on an adhesion-resistant background, and cultured cells of MC3T3-E1 (osteoblast), BMSC (bone mesenchymal stem cell) or NIH3T3 (fibroblast) on those modeled surfaces. We have defined seven characteristic areas of an adhesive microisland and confirmed that they are meaningful to describe cell adhesion behaviors. Those parameters are (1) the critical adhesion area from apoptosis to survival denoted as A∗ or A(c₁), (2) the critical area from adhesion of a single cell to adhesion of multiple cells (A(c₂)), (3) the basic area for one more cell to adhere (A(Δ)), (4) and (5) the characteristic areas of a microisland most probably occupied by one cell (A(peak₁) and two cells (A(peak₂)), (6) and (7) the characteristic areas of a microisland occupied by one cell (A(N₁)) or two cells (A(N₂)) on average. Besides the introduction of those basic parameters, the present paper demonstrates how to determine them experimentally. We further discussed the relationship between those characteristic areas and the spreading area on a non-patterned adhesive surface.
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Affiliation(s)
- Ce Yan
- Key Laboratory of Molecular Engineering of Polymers of Ministry of Education, Department of Macromolecular Science, Advanced Materials Laboratory, Fudan University, Shanghai 200433, China
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491
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492
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Abstract
Stem cells always balance between self-renewal and differentiation. Hence, stem cell culture parameters are critical and need to be continuously refined according to progress in our stem cell biology understanding and the latest technological developments. In the past few years, major efforts have been made to define more precisely the medium composition in which stem cells grow or differentiate. This led to the progressive replacement of ill-defined additives such as serum or feeder cell layers by recombinant cytokines or growth factors. Another example is the control of the oxygen pressure. For many years cell cultures have been done under atmospheric oxygen pressure which is much higher than the one experienced by stem cells in vivo. A consequence of cell metabolism is that cell culture conditions are constantly changing. Therefore, the development of high sensitive monitoring processes and control algorithms is required for ensuring cell culture medium homeostasis. Stem cells also sense the physical constraints of their microenvironment. Rigidity, stiffness, and geometry of the culture substrate influence stem cell fate. Hence, nanotopography is probably as important as medium formulation in the optimization of stem cell culture conditions. Recent advances include the development of synthetic bioinformative substrates designed at the micro- and nanoscale level. On going research in many different fields including stem cell biology, nanotechnology, and bioengineering suggest that our current way to culture cells in Petri dish or flasks will soon be outdated as flying across the Atlantic Ocean in the Lindbergh's plane.
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Affiliation(s)
- Boudewijn van der Sanden
- INSERM U836, Grenoble Institut des Neurosciences, Université Joseph Fourier, CHU Michallon, 38042 Grenoble, France
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493
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Maciaszek JL, Lykotrafitis G. Sickle cell trait human erythrocytes are significantly stiffer than normal. J Biomech 2011; 44:657-61. [DOI: 10.1016/j.jbiomech.2010.11.008] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Revised: 11/02/2010] [Accepted: 11/03/2010] [Indexed: 10/18/2022]
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494
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Nathan AS, Baker BM, Nerurkar NL, Mauck RL. Mechano-topographic modulation of stem cell nuclear shape on nanofibrous scaffolds. Acta Biomater 2011; 7:57-66. [PMID: 20709198 DOI: 10.1016/j.actbio.2010.08.007] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Revised: 07/19/2010] [Accepted: 08/09/2010] [Indexed: 01/14/2023]
Abstract
Stem cells transit along a variety of lineage-specific routes towards differentiated phenotypes. These fate decisions are dependent not just on the soluble chemical cues that are encountered or enforced in vivo and in vitro, but also on physical cues from the cellular microenvironment. These physical cues can consist of both nano- and micro-scale topographical features, as well as mechanical inputs provided passively (from the base properties of the materials to which they adhere) or actively (from extrinsic applied mechanical deformations). A suitable tool to investigate the coordination of these cues lies in nanofibrous scaffolds, which can both dictate cellular and cytoskeletal orientation and facilitate mechanical perturbation of seeded cells. Here, we demonstrate a coordinated influence of scaffold architecture (aligned vs. randomly organized fibers) and tensile deformation on nuclear shape and orientation. Sensitivity of nuclear morphology to scaffold architecture was more pronounced in stem cell populations than in terminally differentiated fibrochondrocytes. Tension applied to the scaffold elicited further alterations in nuclear morphology, greatest in stem cells, that were mediated by the filamentous actin cytoskeleton, but not the microtubule or intermediate filament network. Nuclear perturbations were time and direction dependent, suggesting that the modality and direction of loading influenced nuclear architecture. The present work may provide additional insight into the mechanisms by which the physical microenvironment influences cell fate decisions, and has specific application to the design of new materials for regenerative medicine applications with adult stem cells.
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Affiliation(s)
- Ashwin S Nathan
- Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, 19104, USA
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495
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Igwe J, Amini A, Mikael P, Laurencin C, Nukavarapu S. Nanostructured Scaffolds for Bone Tissue Engineering. ACTIVE IMPLANTS AND SCAFFOLDS FOR TISSUE REGENERATION 2011. [DOI: 10.1007/8415_2010_60] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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496
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Adler AF, Leong KW. Emerging links between surface nanotechnology and endocytosis: impact on nonviral gene delivery. NANO TODAY 2010; 5:553-569. [PMID: 21383869 PMCID: PMC3048656 DOI: 10.1016/j.nantod.2010.10.007] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Significant effort continues to be exerted toward the improvement of transfection mediated by nonviral vectors. These endeavors are often focused on the design of particulate carriers with properties that encourage efficient accumulation at the membrane surface, particle uptake, and endosomal escape. Despite its demonstrated importance in successful nonviral transfection, relatively little investigation has been done to understand the pressures driving internalized vectors into favorable nondegradative endocytic pathways. Improvements in transfection efficiency have been noted for complexes delivered with a substrate-mediated approach, but the reasons behind such enhancements remain unclear. The phenotypic changes exhibited by cells interacting with nano- and micro-featured substrates offer hints that may explain these effects. This review describes nanoscale particulate and substrate parameters that influence both the uptake of nonviral gene carriers and the endocytic phenotype of interacting cells, and explores the molecular links that may mediate these interactions. Substrate-mediated control of endocytosis represents an exciting new design parameter that will guide the creation of efficient transgene carriers.
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Affiliation(s)
- Andrew F. Adler
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, NC 27708, USA
| | - Kam W. Leong
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, NC 27708, USA
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497
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Zhao L, Hu L, Huo K, Zhang Y, Wu Z, Chu PK. Mechanism of cell repellence on quasi-aligned nanowire arrays on Ti alloy. Biomaterials 2010; 31:8341-9. [DOI: 10.1016/j.biomaterials.2010.07.036] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Accepted: 07/06/2010] [Indexed: 01/09/2023]
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498
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Schiele NR, Corr DT, Huang Y, Raof NA, Xie Y, Chrisey DB. Laser-based direct-write techniques for cell printing. Biofabrication 2010; 2:032001. [PMID: 20814088 DOI: 10.1088/1758-5082/2/3/032001] [Citation(s) in RCA: 162] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Fabrication of cellular constructs with spatial control of cell location (+/-5 microm) is essential to the advancement of a wide range of applications including tissue engineering, stem cell and cancer research. Precise cell placement, especially of multiple cell types in co- or multi-cultures and in three dimensions, can enable research possibilities otherwise impossible, such as the cell-by-cell assembly of complex cellular constructs. Laser-based direct writing, a printing technique first utilized in electronics applications, has been adapted to transfer living cells and other biological materials (e.g., enzymes, proteins and bioceramics). Many different cell types have been printed using laser-based direct writing, and this technique offers significant improvements when compared to conventional cell patterning techniques. The predominance of work to date has not been in application of the technique, but rather focused on demonstrating the ability of direct writing to pattern living cells, in a spatially precise manner, while maintaining cellular viability. This paper reviews laser-based additive direct-write techniques for cell printing, and the various cell types successfully laser direct-written that have applications in tissue engineering, stem cell and cancer research are highlighted. A particular focus is paid to process dynamics modeling and process-induced cell injury during laser-based cell direct writing.
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Affiliation(s)
- Nathan R Schiele
- Biomedical Engineering Department, Rensselaer Polytechnic Institute, Troy, NY, USA.
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499
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Can common adhesion molecules and microtopography affect cellular elasticity? A combined atomic force microscopy and optical study. Med Biol Eng Comput 2010; 48:1043-53. [PMID: 20623199 DOI: 10.1007/s11517-010-0657-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2010] [Accepted: 06/03/2010] [Indexed: 10/24/2022]
Abstract
The phenomenon that cells respond to chemical and topographic cues in their surroundings has been widely examined and exploited in many fields ranging from basic life science research to biomedical therapeutics. Adhesion promoting molecules such as poly-L-lysine (PLL) and fibronectin (Fn) are commonly used for in vitro cell assays to promote cell spreading/proliferation on tissue culture plastic and to enhance the biocompatibility of biomedical devices. Likewise, engineered topography is often used to guide cell growth and differentiation. Little is known about how these cues affect the biomechanical properties of cells and subsequent cell function. In this study we have applied atomic force microscopy (AFM) to investigate these biomechanical properties. In the first stage of the study we formulated a rigorous approach to quantify cellular elasticity using AFM. Operational factors, including indentation depth and speed, and mathematical models for data fitting have been systematically evaluated. We then quantified how PLL, Fn and microtopography affected cellular elasticity and the organization of the cytoskeleton. Cellular elasticity after 1 day in culture was greater on a Fn-coated surface as compared to PLL or glass. These statistically significant differences disappeared after two more days in culture. In contrast, the significantly higher elasticity associated with cells grown on micrometric grooves remained for at least 3 days. This work sheds light on the apparently simple but debatable questions: "Are engineered chemical cues eventually masked by a cell's own matrix proteins and so only exert short-term influence? Does engineered topography as well as engineered chemistry affect cell elasticity?"
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500
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Chung K, DeQUACH JA, Christman KL. NANOPATTERNED INTERFACES FOR CONTROLLING CELL BEHAVIOR. NANO LIFE 2010; 1:63-77. [PMID: 25383101 PMCID: PMC4221096 DOI: 10.1142/s1793984410000055] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Many studies have demonstrated that microscale changes to surface chemistry and topography affect cell adhesion, proliferation, differentiation, and gene expression. More recently, studies have begun to examine cell behavior interactions with structures on the nanoscale since in vivo, cells recognize and adhere to cell adhesion receptors that are spatially organized on this scale. These studies have been enabled through various fabrication methods, many of which were initially developed for the semiconductor industry. This review explores cell responses to a variety of controlled topographical and biochemical cues using an assortment of nanoscale fabrication methods in order to elucidate which pattern dimensions are beneficial for controlling cell adhesion and differentiation.
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Affiliation(s)
- Kevin Chung
- Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive La Jolla, CA 92093-0412, USA
| | - Jessica A DeQUACH
- Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive La Jolla, CA 92093-0412, USA
| | - Karen L Christman
- Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive La Jolla, CA 92093-0412, USA
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