151
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Zouani OF, Chanseau C, Brouillaud B, Bareille R, Deliane F, Foulc MP, Mehdi A, Durrieu MC. Altered nanofeature size dictates stem cell differentiation. J Cell Sci 2012; 125:1217-24. [PMID: 22302989 DOI: 10.1242/jcs.093229] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The differentiation of stem cells can be modulated by physical factors such as the micro- and nano-topography of the extracellular matrix. One important goal in stem cell research is to understand the concept that directs differentiation into a specific cell lineage in the nanoscale environment. Here, we demonstrate that such paths exist by controlling only the micro- and nano-topography of polymer surfaces. Altering the depth (on a nanometric scale) of micro-patterned surface structures allowed increased adhesion of human mesenchymal stem cells (hMSCs) with specific differentiation into osteoblasts, in the absence of osteogenic medium. Small (10 nm) depth patterns promoted cell adhesion without noticeable differentiation, whereas larger depth patterns (100 nm) elicited a collective cell organization, which induced selective differentiation into osteoblast-like cells. This latter response was dictated by stress through focal-adhesion-induced reorganization of F-actin filaments. The results have significant implications for understanding the architectural effects of the in vivo microenvironment and also for the therapeutic use of stem cells.
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Affiliation(s)
- Omar F Zouani
- INSERM, U1026, BioIngénierie Tissulaire, F-33076 Bordeaux, France.
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152
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Hu H, Zhang W, Qiao Y, Jiang X, Liu X, Ding C. Antibacterial activity and increased bone marrow stem cell functions of Zn-incorporated TiO2 coatings on titanium. Acta Biomater 2012; 8:904-15. [PMID: 22023752 DOI: 10.1016/j.actbio.2011.09.031] [Citation(s) in RCA: 230] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 09/22/2011] [Accepted: 09/26/2011] [Indexed: 11/26/2022]
Abstract
In this work, zinc was incorporated into TiO2 coatings on titanium by plasma electrolytic oxidation to obtain the implant with good bacterial inhibition ability and bone-formability. The porous and nanostructured Zn-incorporated TiO2 coatings are built up from pores smaller than 5 μm and grains 20-100 nm in size, in which the element Zn exists as ZnO. The results obtained from the antibacterial studies suggest that the Zn-incorporated TiO2 coatings can greatly inhibit the growth of both Staphylococcus aureus and Escherichia coli, and the ability to inhibit bacteria can be improved by increasing the Zn content in the coatings. Moreover, the in vitro cytocompatibility evaluation demonstrates that the adhesion, proliferation and differentiation of rat bone marrow stem cells (bMSC) on Zn-incorporated coatings are significantly enhanced compared with Zn-free coating and commercially pure Ti plate, and no cytotoxicity appeared on any of the Zn-incorporated TiO2 coatings. Moreover, bMSC express higher level of alkaline phosphatase activity on Zn-incorporated TiO2 coatings and are induced to differentiate into osteoblast cells. The better antibacterial activity, cytocompatibility and the capability to promote bMSC osteogenic differentiation of Zn-incorporated TiO2 coatings may be attributed to the fact that Zn ions can be slowly and constantly released from the coatings. In conclusion, innovative Zn-incorporated TiO2 coatings on titanium with excellent antibacterial activity and biocompatibility are promising candidates for orthopedic and dental implants.
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153
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Conserva E, Menini M, Ravera G, Pera P. The role of surface implant treatments on the biological behavior of SaOS-2 osteoblast-like cells. Anin vitrocomparative study. Clin Oral Implants Res 2012; 24:880-9. [DOI: 10.1111/j.1600-0501.2011.02397.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/19/2011] [Indexed: 11/30/2022]
Affiliation(s)
- Enrico Conserva
- Department of Fixed and Implant Prosthodontics; Genoa University; Genova, Italy
| | - Maria Menini
- Department of Fixed and Implant Prosthodontics; Genoa University; Genova, Italy
| | | | - Paolo Pera
- Department of Fixed and Implant Prosthodontics; Genoa University; Genova, Italy
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154
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Park J, Bauer S, Pittrof A, Killian MS, Schmuki P, von der Mark K. Synergistic control of mesenchymal stem cell differentiation by nanoscale surface geometry and immobilized growth factors on TiO2 nanotubes. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2012; 8:98-107. [PMID: 22095845 DOI: 10.1002/smll.201100790] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Revised: 08/08/2011] [Indexed: 05/18/2023]
Abstract
The aim of this study is to elucidate whether combined environmental signals provided by nanoscale topography and by growth factors control cell behavior of mesenchymal stem cells (MSCs) in a synergistic or simply additive manner. Chondrogenic and osteogenic differentiation of MSCs is studied on vertically aligned TiO(2) nanotubes of size 15 and 100 nm with and without immobilized bone morphogenetic protein-2 (BMP-2). Although BMP-2 coating stimulates both chondrogenic and osteogenic differentiation of MSCs, the response strongly depends on the surface nanoscale geometry of the BMP-2-coated nanotubes. Chondrogenic differentiation is strongly supported on 100 nm BMP-2-coated nanotubes, but not on 15 nm nanotubes, which induce spreading and de-differentiation of chondrocytes. A similar response is observed with primary chondrocytes, which maintain their chondrogenic phenotype on BMP-2-coated 100 nm nanotubes, but de-differentiate on 15 nm nanotubes. In contrast, osteogenic differentiation is greatly enhanced on 15 nm but not on 100 nm BMP-2-coated nanotubes as shown previously. Furthermore, covalent immobilization of BMP-2 rescues MSCs from apoptosis occurring on uncoated 100 nm TiO(2) nanotube surfaces. Thus, combined signals provided by BMP-2 immobilized to a defined lateral nanoscale spacing geometry seem to contain environmental cues that are able to modulate a lineage-specific decision of MSC differentiation and cell survival in a synergistic manner.
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Affiliation(s)
- Jung Park
- Department of Experimental Medicine I, Nikolaus-Fiebiger-Center of Molecular Medicine, Friedrich-Alexander-University of Erlangen-Nuremberg, Glueckstrasse 5, 91054 Erlangen, Germany
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155
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Tsukimura N, Ueno T, Iwasa F, Minamikawa H, Sugita Y, Ishizaki K, Ikeda T, Nakagawa K, Yamada M, Ogawa T. Bone integration capability of alkali- and heat-treated nanobimorphic Ti-15Mo-5Zr-3Al. Acta Biomater 2011; 7:4267-77. [PMID: 21888994 DOI: 10.1016/j.actbio.2011.08.016] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2011] [Revised: 08/11/2011] [Accepted: 08/17/2011] [Indexed: 11/30/2022]
Abstract
The role of nanofeatured titanium surfaces in a number of aspects of in vivo bone-implant integration, and, in particular, their potential advantages over microfeatured titanium surfaces, as well as their specific contribution to osteoconductivity, is largely unknown. This study reports the creation of a unique nanobimorphic titanium surface comprised of nanotrabecular and nanotuft-like structures and determines how the addition of this nanofeature to a microroughened surface affects bone-implant integration. Machined surfaces without microroughness, sandblasted microroughened surfaces, and micro-nano hybrid surfaces created by sandblasting and alkali and heat treatment of Ti-15Mo-5Zr-3Al alloy were subjected to biomechanical, interfacial and histological analyses in a rat model. The presence of microroughness enabled accelerated establishment of biomechanical implant fixation in the early stages of healing compared to the non-microroughened surfaces; however, it did not increase the implant fixation at the late stages of healing. The addition of nanobimorphic features to the microroughened surfaces further increased the implant fixation by as much as 60-100% over the healing time. Bone area within 50 μm of the implant surface, but not beyond this distance, was significantly increased by the presence of nanobimorphic features. Although the percentage of bone-implant contact was also significantly increased by the addition of nanobimorphic features, the greatest improvement was found in the soft tissue intervention between the bone and the implant, which was reduced from >30% to <5%. Mineralized tissue densely deposited with calcium-binding globular proteins was observed in an extensive area of nanobimorphic surfaces after biomechanical testing. This study clearly demonstrates the nanofeature-enhanced osteoconductivity of titanium by an alkali- and heat-treated nanobimorphic surface compared to that by microfeatured surfaces, which results not only in an acceleration but also an improvement of bone-implant integration. The identified biological parameters that successfully detect the advantages of nanofeatures over microfeatures will be useful in evaluating new implant surfaces in future studies.
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Affiliation(s)
- Naoki Tsukimura
- Laboratory of Bone and Implant Sciences (LBIS), The Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, Biomaterials and Hospital Dentistry, UCLA School of Dentistry, Los Angeles, CA, USA
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156
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Abstract
OBJECTIVE This study aims at applying cDNA microarray analysis in vitro for establishing and comparing the osteogenic properties of dental implants with different surface characteristics. MATERIALS AND METHODS Saos-2 osteoblasts were cultured in bottom-cone tubes in presence of 5 different dental implants with various surface characteristics. Cells adherent to dental implants were detached and RNA purified. The expression of 18,401 genes was tested by cDNA microarray. RESULTS The number and viability of cells adherent to different dental implants varied but without any significant statistical difference. Conversely, gene expression was revealed to be a more sensitive biomarker being remarkably different in cells adherent to different implants. The 5 dental implants significantly modulated the expression of 14 osteogenic activities mainly including bone morphogenetic proteins, osteomodulin, and osteoprotegerin. CONCLUSION Despite no significant differences having been found in in vitro cell number and viability, cells adherent to 5 differently surfaced implants showed different gene expression profiles. Thus, to evaluate osteogenesis as related to dental implants, it is important to analyze not only the number of adherent cells but also the activation of genes encoding for osteogenic activities.
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157
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Lim JY, Loiselle AE, Lee JS, Zhang Y, Salvi JD, Donahue HJ. Optimizing the osteogenic potential of adult stem cells for skeletal regeneration. J Orthop Res 2011; 29:1627-33. [PMID: 21509820 PMCID: PMC3263698 DOI: 10.1002/jor.21441] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 03/31/2011] [Indexed: 02/04/2023]
Abstract
Adult stem cells, including mesenchymal stem cells, display plasticity in that they can differentiate toward various lineages including bone cells, cartilage cells, fat cells, and other types of connective tissue cells. However, it is not clear what factors direct adult stem cell lineage commitment and terminal differentiation. Emerging evidence suggests that extracellular physical cues have the potential to control stem cell lineage specification. In this perspective article, we review recent findings on biomaterial surface and mechanical signal regulation of stem cell differentiation. Specifically, we focus on stem cell response to substrate nanoscale topography and fluid flow induced shear stress and how these physical factors may regulate stem cell osteoblastic differentiation in vitro.
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Affiliation(s)
- Jung Yul Lim
- Department of Engineering Mechanics, University of Nebraska, Lincoln, Nebraska 68588
,The Graduate School of Dentistry, Kyung Hee University, Seoul, Korea
| | - Alayna E. Loiselle
- Division of Musculoskeletal Sciences, Department of Orthopaedics and Rehabilitation, Center for Biomedical Devices and Functional Tissue Engineering, College of Medicine, Pennsylvania State University, Hershey, Pennsylvania 17033
| | - Jeong Soon Lee
- Department of Engineering Mechanics, University of Nebraska, Lincoln, Nebraska 68588
| | - Yue Zhang
- Division of Musculoskeletal Sciences, Department of Orthopaedics and Rehabilitation, Center for Biomedical Devices and Functional Tissue Engineering, College of Medicine, Pennsylvania State University, Hershey, Pennsylvania 17033
| | - Joshua D. Salvi
- Weill Cornell Medical College, Cornell University, New York, New York 10021
| | - Henry J. Donahue
- Division of Musculoskeletal Sciences, Department of Orthopaedics and Rehabilitation, Center for Biomedical Devices and Functional Tissue Engineering, College of Medicine, Pennsylvania State University, Hershey, Pennsylvania 17033
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158
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Gallardo-Moreno A, Multigner M, Calzado-Martín A, Méndez-Vilas A, Saldaña L, Galván J, Pacha-Olivenza M, Perera-Núñez J, González-Carrasco J, Braceras I, Vilaboa N, González-Martín M. Bacterial adhesion reduction on a biocompatible Si+ ion implanted austenitic stainless steel. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2011. [DOI: 10.1016/j.msec.2011.07.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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159
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Lee WC, Lim CHYX, Shi H, Tang LAL, Wang Y, Lim CT, Loh KP. Origin of enhanced stem cell growth and differentiation on graphene and graphene oxide. ACS NANO 2011; 5:7334-41. [PMID: 21793541 DOI: 10.1021/nn202190c] [Citation(s) in RCA: 658] [Impact Index Per Article: 50.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The culture of bone marrow derived mesenchymal stem cells (MSCs), as well as the control of its differentiation toward different tissue lineage, is a very important part of tissue engineering, where cells are combined with artificial scaffold to regenerate tissues. Graphene (G) and graphene oxide (GO) sheets are soft membranes with high in-plane stiffness and can potentially serve as a biocompatible, transferable, and implantable platform for stem cell culture. While the healthy proliferation of stem cells on various carbon platforms has been demonstrated, the chemical role of G and GO, if any, in guiding uncommitted stem cells toward differentiated cells is not known. Herein, we report that the strong noncovalent binding abilities of G allow it to act as a preconcentration platform for osteogenic inducers, which accelerate MSCs growing on it toward the osteogenic lineage. The molecular origin of accelerated differentation is investigated by studying the binding abilities of G and GO toward different growth agents. Interestingly, differentiation to adipocytes is greatly suppressed on G because insulin, which is a key regulator for the synthesis of fatty acids, is denatured upon π-π adsorption on G; in contrast, GO does not interfere with adipogenesis due to electrostatic binding with insulin. The different binding interactions and their subsequent influence on stem cell growth and differentiation are ascribed to different degrees of π-π stacking and electrostatic and hydrogen bonding mediated by G and GO.
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Affiliation(s)
- Wong Cheng Lee
- NUS Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences #05-01, National University of Singapore, 28 Medical Drive, 117456, Singapore
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160
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Malmström J, Lovmand J, Kristensen S, Sundh M, Duch M, Sutherland DS. Focal complex maturation and bridging on 200 nm vitronectin but not fibronectin patches reveal different mechanisms of focal adhesion formation. NANO LETTERS 2011; 11:2264-2271. [PMID: 21598955 DOI: 10.1021/nl200447q] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The effects of protein type and pattern size on cell adhesion, spreading, and focal adhesion development are studied. Fibronectin and vitronectin patterns from 0.1 to 3 μm produced by colloidal lithography reveal important differences in how cells adhere to and bridge focal adhesions across protein nanopatterns versus micropatterns. Vinculin and zyxin in focal adhesions but not integrins are seen to bridge ligand gaps. Differences in protein mechanical properties are implicated as important factors in focal adhesion development.
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Affiliation(s)
- Jenny Malmström
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus, Denmark
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161
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Fibronectin distribution on demixed nanoscale topographies. Int J Artif Organs 2011; 34:54-63. [PMID: 21298616 DOI: 10.5301/ijao.2011.6316] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/27/2010] [Indexed: 01/29/2023]
Abstract
PURPOSE It is known that surface nanotopography influences cell adhesion and differentiation. Our aim is to analyze the effect of nanoscale topography on fibronectin adsorption and, afterwards, on cell adhesion in order to rationalize the cell-material interaction by focusing on the state of the intermediate layer of adsorbed fibronectin at the material interphase. METHODS Nanotopographic surfaces were produced by demixing of thin film polymer blends - PLLA and PS - during a high speed spin-casting process. Fibronectin (FN) was adsorbed on the different nanotopographies and the protein distribution was directly observed by atomic force microscopy (AFM). The fraction of the surface covered by the protein was quantified by image analysis, as well as the distribution of FN between peaks and valleys. Focal adhesion protein -vinculin- was immunostained and quantified by image analysis on the different nanoscale surfaces. RESULTS Different nanoscale domains were obtained by changing the composition of the system within a height range of 3 nm to 30 nm. FN tends to adsorb on the peaks of nanoisland topographies, especially in compositions that did not enhance cell adhesion. Moreover, protein distribution between valleys and peaks alters the size of focal adhesion plaques, which grew larger on surfaces with an even distribution of fibronectin. CONCLUSIONS Our results suggest that the surface nanotopography is a key material property capable of influencing protein adsorption. Additionally, the distribution of the protein on the different samples was correlated to the initial ability of cells to adhere in terms of the size of the focal plaques.
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162
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Mozumder MS, Zhu J, Perinpanayagam H. TiO
2
-enriched polymeric powder coatings support human mesenchymal cell spreading and osteogenic differentiation. Biomed Mater 2011; 6:035009. [DOI: 10.1088/1748-6041/6/3/035009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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163
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Orita T, Tomita M, Kato K. Regulation of cellular responses to macroporous inorganic films prepared by the inverse-opal method. Colloids Surf B Biointerfaces 2011; 84:187-97. [DOI: 10.1016/j.colsurfb.2010.12.032] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Accepted: 12/29/2010] [Indexed: 12/25/2022]
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164
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Hamlet S, Ivanovski S. Inflammatory cytokine response to titanium chemical composition and nanoscale calcium phosphate surface modification. Acta Biomater 2011; 7:2345-53. [PMID: 21281745 DOI: 10.1016/j.actbio.2011.01.032] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Revised: 12/22/2010] [Accepted: 01/21/2011] [Indexed: 10/18/2022]
Abstract
Nanoscale surface modification of titanium dental implants with calcium phosphate (CaP) has been shown to achieve superior bone wound healing and osseointegration compared with smooth or microrough titanium surfaces alone. As bone healing has been shown to be influenced by the action of cytokines, this study examined whether changes in cytokine gene expression from RAW 264.7 cells cultured on commercially pure and titanium alloy (Ti-6Al-4V) microrough or nanoscale crystalline CaP-modified surfaces, may influence downstream events in bone wound healing and osseointegration. Whilst no significant difference in the attachment or proliferation of RAW 264.7 cells was observed, the nanoscale CaP-modified surface elicited a gene expression profile with marked down-regulation of a number of pro-inflammatory cytokines and chemokines. Inflammatory cytokine gene expression was further influenced by chemical composition, with lower levels of pro-inflammatory markers noted following exposure of the macrophage-like cells to titanium alloy (Ti-6Al-4V) compared with the commercially pure titanium surface. Down-regulation of pro-inflammatory cytokine gene expression (confirmed at the protein level for TNFα and CCL5), may thus facilitate the enhanced bone wound healing and osseointegration observed clinically with nanoscale calcium phosphate-modified implant surfaces.
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165
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Bjerre L, Bünger C, Baatrup A, Kassem M, Mygind T. Flow perfusion culture of human mesenchymal stem cells on coralline hydroxyapatite scaffolds with various pore sizes. J Biomed Mater Res A 2011; 97:251-63. [PMID: 21442726 DOI: 10.1002/jbm.a.33051] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 12/01/2010] [Accepted: 01/04/2011] [Indexed: 01/22/2023]
Abstract
Bone grafts are widely used in orthopaedic reconstructive surgery, but harvesting of autologous grafts is limited due to donor site complications. Bone tissue engineering is a possible alternative source for substitutes, and to date, mainly small scaffold sizes have been evaluated. The aim of this study was to obtain a clinically relevant substitute size using a direct perfusion culture system. Human bone marrowderived mesenchymal stem cells were seeded on coralline hydroxyapatite scaffolds with 200 μm or 500 μm pores, and resulting constructs were cultured in a perfusion bioreactor or in static culture for up to 21 days and analysed for cell distribution and osteogenic differentiation using histological stainings, alkaline phosphatase activity assay, and real-time RT-PCR on bone markers. We found that the number of cells was higher during static culture at most time points and that the final number of cells was higher in 500 μm constructs as compared with 200 μm constructs. Alkaline phosphatase enzyme activity assays and real time RT-PCR on seven osteogenic markers showed that differentiation occurred primarily and earlier in statically cultured constructs with 200 μm pores compared with 500 μm ones. Adhesion and proliferation of the cells was seen on both scaffold sizes, but the vitality and morphology of cells changed unfavorably during perfusion culture. In contrast to previous studies using spinner flask that show increased cellularity and osteogenic properties of cells when cultured dynamically, the perfusion culture in our study did not enhance the osteogenic properties of cell/scaffold constructs. The statically cultured constructs showed increasing cell numbers and abundant osteogenic differentiation probably because of weak initial cell adhesion due to the surface morphology of scaffolds. Our conclusion is that the specific scaffold surface microstructure and culturing system flow dynamics has a great impact on cell distribution and proliferation and on osteogenic differentiation, and the data presented warrant careful selection of in vitro culture settings to meet the specific requirements of the scaffolds and cells, especially when natural biomaterials with varying morphology are used.
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Affiliation(s)
- Lea Bjerre
- Department of Othopaedics, Orthopaedic Research Laboratory, Laboratory for Molecular Orthopaedics, Aarhus University Hospital, 8000 Aarhus C, Denmark.
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166
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Gallego D, Ferrell NJ, Hansford DJ. Fabrication of Piezoelectric Polyvinylidene Fluoride (PVDF) Microstructures by Soft Lithography for Tissue Engineering and Cell Biology Applications. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-1002-n04-05] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTA method for the fabrication of piezoelectric polyvinylidene fluoride (PVDF) microstructures is described. Embossed and individual features with highly defined geometries at the microscale were obtained using soft lithography-based techniques. Various structure geometries were obtained, including pillars (three different aspect ratios), parallel lines, and criss-crossed lines. SEM characterization revealed uniform patterns with dimensions ranging from 2 μm ñ 15 μm. Human osteosarcoma (HOS) cell cultures were used to evaluate the cytocompatibility of the microstructures. SEM and fluorescence microscopy showed adequate cell adhesion, proliferation, and strong interaction with tips and corners of the microdiscontinuities. Microfabricated piezoelectric PVDF structures could find applications in the fabrication of mechanically active tissue engineering scaffolds, and the development of dynamic sensors at the cellular and subcellular levels.
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167
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Arca T, Proffitt J, Genever P. Generating 3D tissue constructs with mesenchymal stem cells and a cancellous bone graft for orthopaedic applications. Biomed Mater 2011; 6:025006. [PMID: 21358028 DOI: 10.1088/1748-6041/6/2/025006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Bone matrix (BM) is an acellular crosslinked porcine-derived cancellous bone graft, and therefore may provide advantages over other synthetic and naturally derived materials for use in orthopaedic surgery. Here, we analysed the potential of BM to support the growth and differentiation of primary human multipotent stromal cells/mesenchymal stem cells (MSCs) in order to predict in vivo bone regeneration events. Imaging with laser scanning confocal microscopy and scanning electron microscopy showed that 1 day after static seeding, a dense population of viable MSCs could be achieved on scaffolds suggesting they could be used for in vivo delivery of cells to the implant site. Long-term growth analysis by confocal imaging and histology demonstrated that BM was permissive to the growth and the 3D population of primary MSCs and an enhanced green fluorescent protein expressing osteosarcoma cell line, eGFP.MG63s, over several days in culture. Measurement of alkaline phosphatase (ALP) activities and mRNA expression levels of osteogenic markers (Runx-2, ALP, collagen type I, osteonectin, osteocalcin and osteopontin) indicated that BM supported osteogenesis of MSCs when supplemented with osteogenic stimulants. Upregulation of some of these osteogenic markers on BM, but not on tissue culture plastic, under non-osteogenic conditions suggested that BM also had osteoinductive capacities.
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Affiliation(s)
- Turkan Arca
- Department of Biology, University of York, York, YO10 5DD, UK
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168
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Variola F, Brunski J, Orsini G, de Oliveira PT, Wazen R, Nanci A. Nanoscale surface modifications of medically relevant metals: state-of-the art and perspectives. NANOSCALE 2011; 3:335-53. [PMID: 20976359 PMCID: PMC3105323 DOI: 10.1039/c0nr00485e] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Evidence that nanoscale surface properties stimulate and guide various molecular and biological processes at the implant/tissue interface is fostering a new trend in designing implantable metals. Cutting-edge expertise and techniques drawn from widely separated fields, such as nanotechnology, materials engineering and biology, have been advantageously exploited to nanoengineer surfaces in ways that control and direct these processes in predictable manners. In this review, we present and discuss the state-of-the-art of nanotechnology-based approaches currently adopted to modify the surface of metals used for orthopedic and dental applications, and also briefly consider their use in the cardiovascular field. The effects of nanoengineered surfaces on various in vitro molecular and cellular events are firstly discussed. This review also provides an overview of in vivo and clinical studies with nanostructured metallic implants, and addresses the potential influence of nanotopography on biomechanical events at interfaces. Ultimately, the objective of this work is to give the readership a comprehensive picture of the current advances, future developments and challenges in the application of the infinitesimally small to biomedical surface science. We believe that an integrated understanding of the in vitro and particularly of the in vivo behavior is mandatory for the proper exploitation of nanostructured implantable metals and, indeed, of all biomaterials.
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Affiliation(s)
- Fabio Variola
- Faculty of Engineering, Department of Mechanical Engineering, University of Ottawa, Ottawa, ON, K1N 6N5 (Canada)
- Laboratory for the Study of Calcified Tissues and Biomaterials, Faculté de Médecine Dentaire, Université de Montréal, Montréal, QC, H3C 3J7 (Canada)
| | - John Brunski
- Division of Plastic & Reconstructive Surgery, Department of Surgery PSRL, School of Medicine, Stanford University, 257 Campus Drive Stanford, CA 94305 (USA)
| | - Giovanna Orsini
- Department of Clinical Sciences and Stomatology, University of Marche, Via Tronto 10, 66026 Ancona (Italy)
| | - Paulo Tambasco de Oliveira
- Department of Morphology, Stomatology and Physiology, University of São Paulo, Ribeirão Preto, SP, 14040-904 (Brazil)
| | - Rima Wazen
- Laboratory for the Study of Calcified Tissues and Biomaterials, Faculté de Médecine Dentaire, Université de Montréal, Montréal, QC, H3C 3J7 (Canada)
| | - Antonio Nanci
- Laboratory for the Study of Calcified Tissues and Biomaterials, Faculté de Médecine Dentaire, Université de Montréal, Montréal, QC, H3C 3J7 (Canada)
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169
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Surface Roughening of Polystyrene and Poly(methyl methacrylate) in Ar/O2 Plasma Etching. Polymers (Basel) 2010. [DOI: 10.3390/polym2040649] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
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170
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Characterization and biocompatibility of nanohybrid scaffold prepared via in situ crystallization of hydroxyapatite in chitosan matrix. Colloids Surf B Biointerfaces 2010; 81:640-7. [DOI: 10.1016/j.colsurfb.2010.08.017] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Revised: 08/09/2010] [Accepted: 08/10/2010] [Indexed: 11/22/2022]
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171
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Anselme K, Davidson P, Popa A, Giazzon M, Liley M, Ploux L. The interaction of cells and bacteria with surfaces structured at the nanometre scale. Acta Biomater 2010; 6:3824-46. [PMID: 20371386 DOI: 10.1016/j.actbio.2010.04.001] [Citation(s) in RCA: 451] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Revised: 03/30/2010] [Accepted: 04/01/2010] [Indexed: 12/22/2022]
Abstract
The current development of nanobiotechnologies requires a better understanding of cell-surface interactions on the nanometre scale. Recently, advances in nanoscale patterning and detection have allowed the fabrication of appropriate substrates and the study of cell-substrate interactions. In this review we discuss the methods currently available for nanoscale patterning and their merits, as well as techniques for controlling the surface chemistry of materials at the nanoscale without changing the nanotopography and the possibility of truly characterizing the surface chemistry at the nanoscale. We then discuss the current knowledge of how a cell can interact with a substrate at the nanoscale and the effect of size, morphology, organization and separation of nanofeatures on cell response. Moreover, cell-substrate interactions are mediated by the presence of proteins adsorbed from biological fluids on the substrate. Many questions remain on the effect of nanotopography on protein adsorption. We review papers related to this point. As all these parameters have an influence on cell response, it is important to develop specific studies to point out their relative influence, as well as the biological mechanisms underlying cell responses to nanotopography. This will be the basis for future research in this field. An important topic in tissue engineering is the effect of nanoscale topography on bacteria, since cells have to compete with bacteria in many environments. The limited current knowledge of this topic is also discussed in the light of using topography to encourage cell adhesion while limiting bacterial adhesion. We also discuss current and prospective applications of cell-surface interactions on the nanoscale. Finally, based on questions raised previously that remain to be solved in the field, we propose future directions of research in materials science to help elucidate the relative influence of the physical and chemical aspects of nanotopography on bacteria and cell response with the aim of contributing to the development of nanobiotechnologies.
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172
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Cells preferentially grow on rough substrates. Biomaterials 2010; 31:7205-12. [DOI: 10.1016/j.biomaterials.2010.06.016] [Citation(s) in RCA: 209] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Accepted: 06/04/2010] [Indexed: 11/17/2022]
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173
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Salvi JD, Lim JY, Donahue HJ. Increased mechanosensitivity of cells cultured on nanotopographies. J Biomech 2010; 43:3058-62. [PMID: 20851397 DOI: 10.1016/j.jbiomech.2010.07.015] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Revised: 07/10/2010] [Accepted: 07/15/2010] [Indexed: 11/19/2022]
Abstract
Enhancing cellular mechanosensitivity is recognized as a novel tool for successful musculoskeletal tissue engineering. We examined the hypothesis that mechanosensitivity of human mesenchymal stem cells (hMSCs) is enhanced on nanotopographic substrates relative to flat surfaces. hMSCs were cultured on polymer-demixed, randomly distributed nanoisland surfaces with varying island heights and changes in intracellular calcium concentration, [Ca(2+)](i), in response to fluid flow induced shear stress were quantifide. Stem cells cultured on specific scale nanotopographies displayed greater intracellular calcium responses to fluid flow. hMSCs cultured on 10-20nm high nanoislands displayed a greater percentage of cells responding in calcium relative to cells cultured on flat control, and showed greater average [Ca(2+)](i) increase relative to cells cultured on other nanoislands (45-80nm high nanoislands). As [Ca(2+)](i) is an important regulator of downstream signaling, as well as proliferation and differentiation of hMSCs, this observation suggests that specific scale nanotopographies provide an optimal milieu for promoting stem cell mechanotransduction activity. That mechanical signals and substrate nanotopography may synergistically regulate cell behavior is of significant interest in the development of regenerative medicine protocols.
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Affiliation(s)
- Joshua D Salvi
- Weill Cornell Medical College, Cornell University, New York, NY 10021, USA
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174
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Mour M, Das D, Winkler T, Hoenig E, Mielke G, Morlock MM, Schilling AF. Advances in Porous Biomaterials for Dental and Orthopaedic Applications. MATERIALS 2010. [PMCID: PMC5445918 DOI: 10.3390/ma3052947] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The connective hard tissues bone and teeth are highly porous on a micrometer scale, but show high values of compression strength at a relatively low weight. The fabrication of porous materials has been actively researched and different processes have been developed that vary in preparation complexity and also in the type of porous material that they produce. Methodologies are available for determination of pore properties. The purpose of the paper is to give an overview of these methods, the role of porosity in natural porous materials and the effect of pore properties on the living tissues. The minimum pore size required to allow the ingrowth of mineralized tissue seems to be in the order of 50 µm: larger pore sizes seem to improve speed and depth of penetration of mineralized tissues into the biomaterial, but on the other hand impair the mechanical properties. The optimal pore size is therefore dependent on the application and the used material.
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Affiliation(s)
- Meenakshi Mour
- Department of Mechanical Engineering, National Institute of Technology, Durgapur 713209, India; E-Mails: (M.M.); (D.D.)
| | - Debarun Das
- Department of Mechanical Engineering, National Institute of Technology, Durgapur 713209, India; E-Mails: (M.M.); (D.D.)
| | - Thomas Winkler
- Biomechanics Section, Hamburg University of Technology, Hamburg D-21073, Germany; E-Mails: (T.W.); (E.H.); (G.M.); (M.M.M.)
| | - Elisa Hoenig
- Biomechanics Section, Hamburg University of Technology, Hamburg D-21073, Germany; E-Mails: (T.W.); (E.H.); (G.M.); (M.M.M.)
| | - Gabriela Mielke
- Biomechanics Section, Hamburg University of Technology, Hamburg D-21073, Germany; E-Mails: (T.W.); (E.H.); (G.M.); (M.M.M.)
| | - Michael M. Morlock
- Biomechanics Section, Hamburg University of Technology, Hamburg D-21073, Germany; E-Mails: (T.W.); (E.H.); (G.M.); (M.M.M.)
| | - Arndt F. Schilling
- Biomechanics Section, Hamburg University of Technology, Hamburg D-21073, Germany; E-Mails: (T.W.); (E.H.); (G.M.); (M.M.M.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel: +49-(0)40-42878-4361; Fax: +49-(0)40-42878-2996
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175
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Classification of osseointegrated implant surfaces: materials, chemistry and topography. Trends Biotechnol 2010; 28:198-206. [DOI: 10.1016/j.tibtech.2009.12.003] [Citation(s) in RCA: 354] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2009] [Revised: 12/01/2009] [Accepted: 12/15/2009] [Indexed: 11/18/2022]
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176
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Olivares-Navarrete R, Hyzy S, Hutton D, Erdman C, Wieland M, Boyan BD, Schwartz Z. Direct and indirect effects of microstructured titanium substrates on the induction of mesenchymal stem cell differentiation towards the osteoblast lineage. Biomaterials 2010; 31:2728-35. [PMID: 20053436 PMCID: PMC2821717 DOI: 10.1016/j.biomaterials.2009.12.029] [Citation(s) in RCA: 235] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2009] [Accepted: 12/11/2009] [Indexed: 12/17/2022]
Abstract
Microstructured and high surface energy titanium substrates increase osseointegration in vivo. In vitro, osteoblast differentiation is increased, but effects of the surface directly on multipotent mesenchymal stem cells (MSCs) and consequences for MSCs in the peri-implant environment are not known. We evaluated responses of human MSCs to substrate surface properties and examined the underlying mechanisms involved. MSCs exhibited osteoblast characteristics (alkaline phosphatase, RUNX2, and osteocalcin) when grown on microstructured Ti; this effect was more robust with increased hydrophilicity. Factors produced by osteoblasts grown on microstructured Ti were sufficient to induce co-cultured MSC differentiation to osteoblasts. Silencing studies showed that this was due to signaling via alpha2beta1 integrins in osteoblasts on the substrate surface and paracrine action of secreted Dkk2. Thus, human MSCs are sensitive to substrate properties that induce osteoblastic differentiation; osteoblasts interact with these surface properties via alpha2beta1 and secrete Dkk2, which acts on distal MSCs.
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Affiliation(s)
- Rene Olivares-Navarrete
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, Georgia, 30332
| | - Sharon Hyzy
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, Georgia, 30332
| | - Daphne Hutton
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, Georgia, 30332
| | - Christopher Erdman
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, Georgia, 30332
| | - Marco Wieland
- NanoPowers SA, Ave de Beaumont 20, Lausanne, Switzerland
| | - Barbara D. Boyan
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, Georgia, 30332
| | - Zvi Schwartz
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 315 Ferst Drive NW, Atlanta, Georgia, 30332
- Department of Periodontics, University of Texas Health Science Center at San Antonio, San Antonio, Texas
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177
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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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178
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González-García C, Sousa SR, Moratal D, Rico P, Salmerón-Sánchez M. Effect of nanoscale topography on fibronectin adsorption, focal adhesion size and matrix organisation. Colloids Surf B Biointerfaces 2010; 77:181-90. [PMID: 20185279 DOI: 10.1016/j.colsurfb.2010.01.021] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Revised: 12/21/2009] [Accepted: 01/28/2010] [Indexed: 11/15/2022]
Abstract
Phase separation of PLLA/PS (50/50, w/w) solutions during a spin-casting process gives rise to well-defined nanotopographies of 14, 29 and 45 nm deep pits depending on the concentration of the solution. Their influence on the biological activity of fibronectin (FN) was investigated. FN adsorption was quantified by radiolabelling the protein. The amount of adsorbed FN was higher on the 14 nm deep pit nanotopography than on the other two surfaces. FN distribution between valleys and peaks was investigated by AFM combined with image analysis. FN tends to adsorb preferentially on the valleys of the nanotopography only for the 14 nm system and when adsorbed from solutions of concentration lower than 10 microg/ml. Higher concentration of the FN solution leads to evenly distribution of the protein throughout the surface; moreover, there is no difference in the distribution of the protein between valleys and peaks for the other two systems (29 and 45 nm) irrespective of the concentration of the FN solution. The biological activity of the adsorbed protein layer was assessed by investigating MC3T3 osteoblast-like cells adhesion, FN reorganisation and late matrix formation on the different substrates. Even if initial cell adhesion is excellent for every substrate, the size of the focal adhesion plaques increases as the size of the pits in the nanotopography does. This is correlated to FN reorganisation, which only takes places on the 29 and 45 nm deep pits surfaces, where enhanced late matrix production was also found.
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Affiliation(s)
- Cristina González-García
- Center for Biomaterials and Tissue Engineering, Universidad Politécnica de Valencia, 46022 Valencia, Spain
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179
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The influence of nanoscale grooved substrates on osteoblast behavior and extracellular matrix deposition. Biomaterials 2010; 31:3307-16. [PMID: 20122723 DOI: 10.1016/j.biomaterials.2010.01.034] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2009] [Accepted: 01/09/2010] [Indexed: 11/24/2022]
Abstract
To fight bone diseases characterized by poor bone quality like osteoporosis and osteoarthritis, as well as in reconstructive surgery, there is a need for a new generation of implantable biomaterials. It is envisioned that implant surfaces can be improved by mimicking the natural extracellular matrix of bone tissue, which is highly a organized nano-composite. In this study we aimed to get a better understanding of osteoblast response to nanometric grooved substrates varying in height, width and spacing. A throughput screening biochip was created using electron beam lithography. Subsequently, uniform large-scale nanogrooved substrates were created using laser interference lithography and reactive ion etching. Results showed that osteoblasts were responsive to nanopatterns down to 75 nm in width and 33nm in depth. SEM and TEM studies showed that an osteoblast-driven calcium phosphate (CaP) mineralization was observed to follow the surface pattern dimensions. Strikingly, aligned mineralization was found on even smaller nanopatterns of 50 nm in width and 17 nm in depth. A single cell based approach for real time PCR demonstrated that osteoblast-specific gene expression was increased on nanopatterns relative to a smooth control. The results indicate that nanogrooves can be a very promising tool to direct the bone response at the interface between an implant and the bone tissue.
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180
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Bucci-Sabattini V, Cassinelli C, Coelho PG, Minnici A, Trani A, Ehrenfest DMD. Effect of titanium implant surface nanoroughness and calcium phosphate low impregnation on bone cell activity in vitro. ACTA ACUST UNITED AC 2010; 109:217-24. [DOI: 10.1016/j.tripleo.2009.09.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2009] [Revised: 09/03/2009] [Accepted: 09/05/2009] [Indexed: 10/20/2022]
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181
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Myllymaa S, Kaivosoja E, Myllymaa K, Sillat T, Korhonen H, Lappalainen R, Konttinen YT. Adhesion, spreading and osteogenic differentiation of mesenchymal stem cells cultured on micropatterned amorphous diamond, titanium, tantalum and chromium coatings on silicon. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2010; 21:329-341. [PMID: 19655235 DOI: 10.1007/s10856-009-3836-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Accepted: 07/22/2009] [Indexed: 05/28/2023]
Abstract
It was hypothesized that human mesenchymal stromal cell (hMSC) can be guided by patterned and plain amorphous diamond (AD), titanium (Ti), tantalum (Ta) and chromium (Cr) coatings, produced on silicon wafer using physical vapour deposition and photolithography. At 7.5 h hMSCs density was 3.0-3.5 x higher (P < 0.0003, except Ti) and cells were smaller (68 vs. 102 microm, P 0.000006-0.02) on patterns than on silicon background. HMSC-covered surface of the background silicon was lower on Ti than AD patterns (P = 0.015), but at 5 days this had reversed (P = 0.006). At 7.5 h focal vinculin adhesions and actin cytoskeleton were outgoing from pattern edges so cells assumed geometric square shapes. Patterns allowed induced osteogenesis, but less effectively than plain surfaces, except for AD, which could be used to avoid osseointegration. All these biomaterial patterns exert direct early, intermediate and late guidance on hMSCs and osteogenic differentiation, but indirect interactions exist with cells on silicon background.
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Affiliation(s)
- Sami Myllymaa
- Department of Physics, University of Kuopio, Kuopio, Finland.
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182
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Tang J, Peng R, Ding J. The regulation of stem cell differentiation by cell-cell contact on micropatterned material surfaces. Biomaterials 2009; 31:2470-6. [PMID: 20022630 DOI: 10.1016/j.biomaterials.2009.12.006] [Citation(s) in RCA: 246] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2009] [Accepted: 12/01/2009] [Indexed: 10/20/2022]
Abstract
Using the material technique recently developed by us, we prepared a micropattern on poly(ethylene glycol) (PEG) hydrogel to keep background resistant to cell adhesion for a long time, which made examination of differentiation of localized stem cells available. Our micropattern designed in this paper prevented or ensured contact between cells adhering in arginine-glycine-aspartic acid (RGD) microdomains, and thus afforded a unique way to study the effects of cell-cell contact on the lineage differentiation of stem cells while ruling out the interference of soluble factors or cell seeding concentration etc. As demonstration, mesenchymal stem cells derived from rats were examined in this study, and both osteogenic and adipogenic differentiations were found to be regulated by cell-cell contact. Isolated cells exhibited less significant differentiation than paired or aggregated cells. For those stem cells in contact, the extent of differentiation was fairly linearly related to the extent of contact characterized by coordination number. Additionally, we revealed the existence of some unknown cues besides gap junction responsible for such effects of cell-cell contact.
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Affiliation(s)
- Jian Tang
- 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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183
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Biocompatibility and in vitro antineoplastic drug-loaded trial of titania nanotubes prepared by anodic oxidation of a pure titanium. ACTA ACUST UNITED AC 2009. [DOI: 10.1007/s11426-009-0240-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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184
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Hori N, Iwasa F, Ueno T, Takeuchi K, Tsukimura N, Yamada M, Hattori M, Yamamoto A, Ogawa T. Selective cell affinity of biomimetic micro-nano-hybrid structured TiO2 overcomes the biological dilemma of osteoblasts. Dent Mater 2009; 26:275-87. [PMID: 20006380 DOI: 10.1016/j.dental.2009.11.077] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2009] [Revised: 11/13/2009] [Accepted: 11/18/2009] [Indexed: 01/25/2023]
Abstract
OBJECTIVE There is a great demand for dental implant surfaces to accelerate the process of peri-implant bone generation to reduce its healing time and enable early loading. To this end, an inverse correlation between the proliferation and functional maturation (differentiation) in osteoblasts presents a challenge for the rapid generation of greater amounts of bone. For instance, osteoblasts exhibit faster differentiation but slower proliferation on micro-roughened titanium surfaces. Using a unique micro-nano-hierarchical topography of TiO(2) that mimics biomineralized matrices, this study demonstrates that this challenge can be overcome without the use of biological agents. METHODS Titanium disks of grade 2 commercially pure titanium were prepared by machining (smooth surface). To create a microtexture with peaks and valleys (micropit surface), titanium disks were acid-etched. To create 200-nm TiO(2) nanonodules within the micropits (nanonodule-in-micropit surface), TiO(2) was sputter-deposited onto the acid-etched surface. Rat bone marrow-derived osteoblasts and NIH3T3 fibroblasts were cultured on machined smooth, micropit, and nanonodule-in-micropit surfaces. RESULTS Despite the substantially increased surface roughness, the addition of 200-nm nanonodules to micropits increased osteoblast proliferation while enhancing their functional differentiation. In contrast, this nanonodule-in-micropit surface decreased proliferation and function in fibroblasts. SIGNIFICANCE The data suggest the establishment of cell-selectively functionalized nano-in-micro smart titanium surfaces that involve a regulatory effect on osteoblast proliferation, abrogating the inhibitory mechanism on the micropitted surface, while enhancing their functional differentiation. Biomimetic and controllable nature of this nanonodules-in-micropits surface may offer a novel micro-to-nanoscale hierarchical platform to biologically optimize nanofeatures of biomaterials. Particularly, this micro-nano-hybrid surface may be an effective approach to improve current dental implant surfaces for accelerated bone integration.
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Affiliation(s)
- Norio Hori
- The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, Biomaterials and Hospital Dentistry, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095-1668, USA
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185
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von der Mark K, Park J, Bauer S, Schmuki P. Nanoscale engineering of biomimetic surfaces: cues from the extracellular matrix. Cell Tissue Res 2009; 339:131-53. [DOI: 10.1007/s00441-009-0896-5] [Citation(s) in RCA: 280] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Accepted: 10/08/2009] [Indexed: 11/29/2022]
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186
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Biggs MJP, Richards RG, Gadegaard N, McMurray RJ, Affrossman S, Wilkinson CDW, Oreffo ROC, Dalby MJ. Interactions with nanoscale topography: adhesion quantification and signal transduction in cells of osteogenic and multipotent lineage. J Biomed Mater Res A 2009; 91:195-208. [PMID: 18814275 DOI: 10.1002/jbm.a.32196] [Citation(s) in RCA: 145] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Polymeric medical devices widely used in orthopedic surgery play key roles in fracture fixation and orthopedic implant design. Topographical modification and surface micro-roughness of these devices regulate cellular adhesion, a process fundamental in the initiation of osteoinduction and osteogenesis. Advances in fabrication techniques have evolved the field of surface modification; in particular, nanotechnology has allowed the development of nanoscale substrates for the investigation into cell-nanofeature interactions. In this study human osteoblasts (HOBs) were cultured on ordered nanoscale pits and random nano "craters" and "islands". Adhesion subtypes were quantified by immunofluorescent microscopy and cell-substrate interactions investigated via immuno-scanning electron microscopy. To investigate the effects of these substrates on cellular function 1.7 k microarray analysis was used to establish gene profiles of enriched STRO-1+ progenitor cell populations cultured on these nanotopographies. Nanotopographies affected the formation of adhesions on experimental substrates. Adhesion formation was prominent on planar control substrates and reduced on nanocrater and nanoisland topographies; nanopits, however, were shown to inhibit directly the formation of large adhesions. STRO-1+ progenitor cells cultured on experimental substrates revealed significant changes in genetic expression. This study implicates nanotopographical modification as a significant modulator of osteoblast adhesion and cellular function in mesenchymal populations.
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Affiliation(s)
- Manus J P Biggs
- Centre for Cell Engineering, Institute of Biomedical and Life Sciences, Joseph Black Building, University of Glasgow, Glasgow G128QQ, United Kingdom.
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187
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Markert LD, Lovmand J, Foss M, Lauridsen RH, Lovmand M, Füchtbauer EM, Füchtbauer A, Wertz K, Besenbacher F, Pedersen FS, Duch M. Identification of Distinct Topographical Surface Microstructures Favoring Either Undifferentiated Expansion or Differentiation of Murine Embryonic Stem Cells. Stem Cells Dev 2009; 18:1331-42. [DOI: 10.1089/scd.2009.0114] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Lotte D’Andrea Markert
- Interdisciplinary Nanoscience Center (iNANO), Århus University, Århus, Denmark
- Department of Molecular Biology, Århus University, Århus, Denmark
| | - Jette Lovmand
- Interdisciplinary Nanoscience Center (iNANO), Århus University, Århus, Denmark
- Department of Molecular Biology, Århus University, Århus, Denmark
| | - Morten Foss
- Interdisciplinary Nanoscience Center (iNANO), Århus University, Århus, Denmark
| | - Rune Hoff Lauridsen
- Interdisciplinary Nanoscience Center (iNANO), Århus University, Århus, Denmark
- Department of Molecular Biology, Århus University, Århus, Denmark
| | - Michael Lovmand
- Department of Physics and Astronomy, Århus University, Århus, Denmark
| | | | | | - Karin Wertz
- DSM Nutritional Products Ltd, Basel, Switzerland
| | - Flemming Besenbacher
- Interdisciplinary Nanoscience Center (iNANO), Århus University, Århus, Denmark
- Department of Physics and Astronomy, Århus University, Århus, Denmark
| | - Finn Skou Pedersen
- Interdisciplinary Nanoscience Center (iNANO), Århus University, Århus, Denmark
- Department of Molecular Biology, Århus University, Århus, Denmark
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188
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Cellular behavior on TiO2 nanonodular structures in a micro-to-nanoscale hierarchy model. Biomaterials 2009; 30:5319-29. [DOI: 10.1016/j.biomaterials.2009.06.021] [Citation(s) in RCA: 248] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2009] [Accepted: 06/12/2009] [Indexed: 11/24/2022]
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189
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Singhatanadgit W. Biological Responses to New Advanced Surface Modifications of Endosseous Medical Implants. ACTA ACUST UNITED AC 2009. [DOI: 10.4137/btri.s3150] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Implantable medical devices are increasingly important in the practice of modern medicine. However, patients with severely poor bone quality and quantity require highest implant osseointegration for the long-term success. A number of newly-developed advanced surface modifications of medical implants have recently been introduced to the medical implant system. Understanding the mechanisms by which osteogenic cells respond to such materials is therefore of major importance in developing the most effective materials to promote functional osseointegration. Diverse studies using materials with a wide range of new surface modification techniques have demonstrated the pivotal role of surface treatments in cell adhesion, proliferation and lineage specific differentiation. These events underlie the tissue responses required for bone healing following implant placement, with the interaction between adsorbed proteins on the implant surface and surrounding cells eliciting body responses to the treated implant surface. This review illustrates tissue responses to the implant material following implant placement and highlights cellular responses to new advanced implant surface modifications. Such information is of utmost importance to further develop several new advanced surface modifications to be used in the new era medical implantable devices.
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Affiliation(s)
- Weerachai Singhatanadgit
- Faculty of Dentistry, Thammasat University, 99 Moo 18, Paholyothin Rd., Klong-Luang, Pathum-Thani, Thailand
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190
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Biggs MJP, Richards RG, Gadegaard N, Wilkinson CDW, Oreffo ROC, Dalby MJ. The use of nanoscale topography to modulate the dynamics of adhesion formation in primary osteoblasts and ERK/MAPK signalling in STRO-1+ enriched skeletal stem cells. Biomaterials 2009; 30:5094-103. [PMID: 19539986 DOI: 10.1016/j.biomaterials.2009.05.049] [Citation(s) in RCA: 185] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Accepted: 05/21/2009] [Indexed: 12/14/2022]
Abstract
The physiochemical characteristics of a material with in vivo applications are critical for the clinical success of the implant and regulate both cellular adhesion and differentiated cellular function. Topographical modification of an orthopaedic implant may be a viable method to guide tissue integration and has been shown in vitro to dramatically influence osteogenesis, inhibit bone resorption and regulate integrin mediated cell adhesion. Integrins function as force dependant mechanotransducers, acting via the actin cytoskeleton to translate tension applied at the tissue level to changes in cellular function via intricate signalling pathways. In particular the ERK/MAPK signalling cascade is a known regulator of osteospecific differentiation and function. Here we investigate the effects of nanoscale pits and grooves on focal adhesion formation in human osteoblasts (HOBs) and the ERK/MAPK signalling pathway in mesenchymal populations. Nanopit arrays disrupted adhesion formation and cellular spreading in HOBs and impaired osteospecific differentiation in skeletal stem cells. HOBs cultured on 10 microm wide groove/ridge arrays formed significantly less focal adhesions than cells cultured on planar substrates and displayed negligible differentiation along the osteospecific lineage, undergoing up-regulations in the expression of adipospecific genes. Conversely, osteospecific function was correlated to increased integrin mediated adhesion formation and cellular spreading as noted in HOBS cultured on 100 microm wide groove arrays. Here osteospecific differentiation and function was linked to focal adhesion growth and FAK mediated activation of the ERK/MAPK signalling pathway in mesenchymal populations.
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Affiliation(s)
- Manus J P Biggs
- Centre for Cell Engineering, Institute of Biomedical and Life Sciences, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, UK.
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191
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Kirmizidis G, Birch MA. Microfabricated Grooved Substrates Influence Cell–Cell Communication and Osteoblast Differentiation In Vitro. Tissue Eng Part A 2009; 15:1427-36. [DOI: 10.1089/ten.tea.2008.0137] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- George Kirmizidis
- Musculoskeletal Research Group, Institute for Cellular Medicine, The Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Mark A. Birch
- Musculoskeletal Research Group, Institute for Cellular Medicine, The Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom
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192
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Fabrication of pillar-like titania nanostructures on titanium and their interactions with human skeletal stem cells. Acta Biomater 2009; 5:1433-41. [PMID: 19208503 DOI: 10.1016/j.actbio.2009.01.007] [Citation(s) in RCA: 213] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2008] [Revised: 12/12/2008] [Accepted: 01/08/2009] [Indexed: 01/16/2023]
Abstract
Surface nanotopography is known to influence the interaction of human skeletal (mesenchymal) stem cells (hMSC) with a material surface. While most surface nanopatterning has been performed on polymer-based surfaces there is a need for techniques to produce well-defined topography features with tuneable sizes on relevant load-bearing implant materials such as titanium (Ti). In this study titania nanopillar structures with heights of either 15, 55 or 100 nm were produced on Ti surfaces using anodization through a porous alumina mask. The influence of the surface structure heights on hMSC adhesion, spreading, cytoskeletal formation and differentiation was examined. The 15 nm high topography features resulted in the greatest cell response with bone matrix nodule forming on the Ti surface after 21 days.
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193
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Differential in-gel electrophoresis (DIGE) analysis of human bone marrow osteoprogenitor cell contact guidance. Acta Biomater 2009; 5:1137-46. [PMID: 19103513 DOI: 10.1016/j.actbio.2008.11.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Revised: 10/30/2008] [Accepted: 11/06/2008] [Indexed: 12/29/2022]
Abstract
We have used a recent comparative proteomics technique, differential in-gel electrophoresis (DIGE), to study osteoprogenitor cell response to contact guidance in grooves. In order to increase protein output from small sample sizes, we used bioreactor culture before protein extraction and gel electrophoresis. Mass spectroscopy was used for protein identification. A number of distinct proteins were observed to exhibit significant changes in expression. These changes in protein expression suggest that the cells respond to tailored grooved topographies, with alterations in their proteome concurrent with changes in osteoprogenitor phenotype.
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194
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Li J, Dou Y, Yang J, Yin Y, Zhang H, Yao F, Wang H, Yao K. Surface characterization and biocompatibility of micro- and nano-hydroxyapatite/chitosan-gelatin network films. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2009. [DOI: 10.1016/j.msec.2008.09.038] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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195
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You J, Heo JS, Lee J, Kim HS, Kim HO, Kim E. A Fluorescent Polymer for Patterning of Mesenchymal Stem Cells. Macromolecules 2009. [DOI: 10.1021/ma802722q] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jungmok You
- Department of Chemical and Biomolecular Engineering, Yonsei University, Cell Therapy Center, Severance Hospital, College of Medicine, Yonsei University, and Department of Laboratory Medicine, College of Medicine, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749, Korea
| | - June Seok Heo
- Department of Chemical and Biomolecular Engineering, Yonsei University, Cell Therapy Center, Severance Hospital, College of Medicine, Yonsei University, and Department of Laboratory Medicine, College of Medicine, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749, Korea
| | - Jiyea Lee
- Department of Chemical and Biomolecular Engineering, Yonsei University, Cell Therapy Center, Severance Hospital, College of Medicine, Yonsei University, and Department of Laboratory Medicine, College of Medicine, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749, Korea
| | - Han-Soo Kim
- Department of Chemical and Biomolecular Engineering, Yonsei University, Cell Therapy Center, Severance Hospital, College of Medicine, Yonsei University, and Department of Laboratory Medicine, College of Medicine, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749, Korea
| | - Hyun Ok Kim
- Department of Chemical and Biomolecular Engineering, Yonsei University, Cell Therapy Center, Severance Hospital, College of Medicine, Yonsei University, and Department of Laboratory Medicine, College of Medicine, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749, Korea
| | - Eunkyoung Kim
- Department of Chemical and Biomolecular Engineering, Yonsei University, Cell Therapy Center, Severance Hospital, College of Medicine, Yonsei University, and Department of Laboratory Medicine, College of Medicine, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749, Korea
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196
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Park J, Bauer S, Schlegel KA, Neukam FW, von der Mark K, Schmuki P. TiO2 nanotube surfaces: 15 nm--an optimal length scale of surface topography for cell adhesion and differentiation. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2009; 5:666-71. [PMID: 19235196 DOI: 10.1002/smll.200801476] [Citation(s) in RCA: 330] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Affiliation(s)
- Jung Park
- Department of Experimental Medicine I, Nikolaus-Fiebiger-Center of Molecular Medicine Friedrich-Alexander-University of Erlangen-Nuremberg, 91054 Erlangen, Germany
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197
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Martínez E, Lagunas A, Mills CA, Rodríguez-Seguí S, Estévez M, Oberhansl S, Comelles J, Samitier J. Stem cell differentiation by functionalized micro- and nanostructured surfaces. Nanomedicine (Lond) 2009; 4:65-82. [PMID: 19093897 DOI: 10.2217/17435889.4.1.65] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
New fabrication technologies and, in particular, new nanotechnologies have provided biomaterial and biomedical scientists with enormous possibilities when designing customized supports and scaffolds with controlled nanoscale topography and chemistry. The main issue now is how to effectively design these components and choose the appropriate combination of structure and chemistry to tailor towards applications as challenging and complex as stem cell differentiation. Occasionally, an incomplete knowledge of the fundamentals of biological differentiation processes has hampered this issue. However, the recent technological advances in creating controlled cellular microenvironments can be seen as a powerful tool for furthering fundamental biology studies. This article reviews the main strategies followed to achieve solutions to this challenge, particularly emphasizing the working hypothesis followed by the authors to elucidate the mechanisms behind the observed effects of structured surfaces on cell behavior.
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Affiliation(s)
- E Martínez
- Nanobioengineering group, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain.
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198
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Biodegradable poly(ɛ-caprolactone) nanowires for bone tissue engineering applications. Biomaterials 2009; 30:780-8. [DOI: 10.1016/j.biomaterials.2008.10.022] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Accepted: 10/16/2008] [Indexed: 11/21/2022]
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199
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Abstract
Two important goals in stem cell research are to control the cell proliferation without differentiation and to direct the differentiation into a specific cell lineage when desired. Here, we demonstrate such paths by controlling only the nanotopography of culture substrates. Altering the dimensions of nanotubular-shaped titanium oxide surface structures independently allowed either augmented human mesenchymal stem cell (hMSC) adhesion or a specific differentiation of hMSCs into osteoblasts by using only the geometric cues, absent of osteogenic inducing media. hMSC behavior in response to defined nanotube sizes revealed a very dramatic change in hMSC behavior in a relatively narrow range of nanotube dimensions. Small (approximately 30-nm diameter) nanotubes promoted adhesion without noticeable differentiation, whereas larger (approximately 70- to 100-nm diameter) nanotubes elicited a dramatic stem cell elongation (approximately 10-fold increased), which induced cytoskeletal stress and selective differentiation into osteoblast-like cells, offering a promising nanotechnology-based route for unique orthopedics-related hMSC treatments.
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200
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Martínez E, Engel E, Planell J, Samitier J. Effects of artificial micro- and nano-structured surfaces on cell behaviour. Ann Anat 2009; 191:126-35. [DOI: 10.1016/j.aanat.2008.05.006] [Citation(s) in RCA: 262] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2008] [Revised: 05/08/2008] [Accepted: 05/24/2008] [Indexed: 10/21/2022]
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