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Chitosan Scaffolds (chitosan + scaffold)
Selected AbstractsBone Morphogenetic Protein-6-loaded Chitosan Scaffolds Enhance the Osteoblastic Characteristics of MC3T3-E1 CellsARTIFICIAL ORGANS, Issue 1 2010Abdullah C. Akman Abstract The purpose of this study is to investigate the convenience of bone morphogenetic protein-6 (BMP-6)-loaded chitosan scaffolds with preosteoblastic cells for bone tissue engineering. MC3T3-E1 cells were seeded into three different groups: chitosan scaffolds, BMP-6-loaded chitosan scaffolds, and chitosan scaffolds with free BMP-6 in culture medium. Tissue-engineered constructs were characterized by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide assay, scanning electron microscopy (SEM), mineralization assay (von Kossa), alkaline phosphatase (ALP) activity, and osteocalcin (OCN) assays. BMP-6-loaded chitosan scaffolds supported proliferation of the MC3T3-E1 mouse osteogenic cells in a similar pattern as the unloaded chitosan scaffolds group and as the chitosan scaffolds with free BMP-6 group. SEM images of the cell-seeded scaffolds revealed significant acceleration of extracellular matrix synthesis in BMP-6-loaded chitosan scaffolds. Both levels of ALP and OCN were higher in BMP-6-loaded chitosan scaffold group compared with the other two groups. In addition, BMP-6-loaded scaffolds showed strong staining in mineralization assays. These findings suggest that BMP-6-loaded chitosan scaffold supports cellular functions of the osteoblastic cells; therefore, this scaffold is considered as a new promising vehicle for bone tissue engineering applications. [source] Chitosan scaffolds for in vitro buffalo embryonic stem-like cell culture: An approach to tissue engineeringJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007Wah W. Thein-Han Abstract Three-dimensional (3D) porous chitosan scaffolds are attractive candidates for tissue engineering applications. Chitosan scaffolds of 70, 88, and 95% degree of deacetylation (% DD) with the same molecular weight were developed and their properties with buffalo embryonic stem-like (ES-like) cells were investigated in vitro. Scaffolds were fabricated by freezing and lyophilization. They showed open pore structure with interconnecting pores under scanning electron microscopy (SEM). Higher % DD chitosan scaffolds had greater mechanical strength, slower degradation rate, lower water uptake ability, but similar water retention ability, when compared to lower % DD chitosan. As a strategy to tissue engineering, buffalo ES-like cells were cultured on scaffolds for 28 days. It appeared that chitosan was cytocompatible and cells proliferated well on 88 and 95% DD scaffolds. In addition, the buffalo ES-like cells maintained their pluripotency during the culture period. Furthermore, the SEM and histological study showed that the polygonal buffalo ES-like cells proliferated well and attached to the pores. This study proved that 3D biodegradable highly deacetylated chitosan scaffolds are promising candidates for ES-like cell based tissue engineering and this chitosan scaffold and ES cell based system can be used as in vitro model for subsequent clinical applications. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007 [source] Effect of cell seeding concentration on the quality of tissue engineered constructs loaded with adult human articular chondrocytesJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 1 2008Sebastian Concaro Abstract Many aspects of the process of in vitro differentiation of chondrocytes in three-dimensional (3D) scaffolds need to be further investigated. Chitosan scaffolds were produced by freeze-drying 3% w/v 90% DDA chitosan gels. The effect of the cell seeding concentration was evaluated by culturing human adult chondrocytes in chitosan scaffolds After the first passage, cells were seeded into chitosan scaffolds with a diameter of 8 mm. The final cell seeding concentration per cm3 of chitosan scaffold was: Group A, 3 × 106; Group B, 6 × 106; Group C, 12 × 106; and Group D, 25 × 106 cells. After 14 and 28 days in 3D culture, the constructs were assesed for collagen, glucosaminoglycans and DNA content. The mechanical properties of the constructs were determined using a dynamic oscillatory shear test. The histological aspect of the constructs was evaluated using the Bern score. The collagen and GAG concentration increased, varying the cell seeding concentration. There was a significant increase in proteoglycan and hydroxyproline production between groups C and D. The sulphated GAG content increased significantly in the group D as compared to the other groups. The mechanical properties of the different constructs increased over time, from 9.6 G,/kPa at 14 days of 3D culture to 14.6 G,/kPa at 28 days under the same culture conditions. In this study we were able to determine that concentrations of 12,25 million cells/cm2 are needed to increase the matrix production and mechanical properties of human adult chondrocytes under static conditions. Copyright © 2008 John Wiley & Sons, Ltd. [source] Chitosan scaffolds for in vitro buffalo embryonic stem-like cell culture: An approach to tissue engineeringJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007Wah W. Thein-Han Abstract Three-dimensional (3D) porous chitosan scaffolds are attractive candidates for tissue engineering applications. Chitosan scaffolds of 70, 88, and 95% degree of deacetylation (% DD) with the same molecular weight were developed and their properties with buffalo embryonic stem-like (ES-like) cells were investigated in vitro. Scaffolds were fabricated by freezing and lyophilization. They showed open pore structure with interconnecting pores under scanning electron microscopy (SEM). Higher % DD chitosan scaffolds had greater mechanical strength, slower degradation rate, lower water uptake ability, but similar water retention ability, when compared to lower % DD chitosan. As a strategy to tissue engineering, buffalo ES-like cells were cultured on scaffolds for 28 days. It appeared that chitosan was cytocompatible and cells proliferated well on 88 and 95% DD scaffolds. In addition, the buffalo ES-like cells maintained their pluripotency during the culture period. Furthermore, the SEM and histological study showed that the polygonal buffalo ES-like cells proliferated well and attached to the pores. This study proved that 3D biodegradable highly deacetylated chitosan scaffolds are promising candidates for ES-like cell based tissue engineering and this chitosan scaffold and ES cell based system can be used as in vitro model for subsequent clinical applications. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007 [source] Effect of cell seeding concentration on the quality of tissue engineered constructs loaded with adult human articular chondrocytesJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 1 2008Sebastian Concaro Abstract Many aspects of the process of in vitro differentiation of chondrocytes in three-dimensional (3D) scaffolds need to be further investigated. Chitosan scaffolds were produced by freeze-drying 3% w/v 90% DDA chitosan gels. The effect of the cell seeding concentration was evaluated by culturing human adult chondrocytes in chitosan scaffolds After the first passage, cells were seeded into chitosan scaffolds with a diameter of 8 mm. The final cell seeding concentration per cm3 of chitosan scaffold was: Group A, 3 × 106; Group B, 6 × 106; Group C, 12 × 106; and Group D, 25 × 106 cells. After 14 and 28 days in 3D culture, the constructs were assesed for collagen, glucosaminoglycans and DNA content. The mechanical properties of the constructs were determined using a dynamic oscillatory shear test. The histological aspect of the constructs was evaluated using the Bern score. The collagen and GAG concentration increased, varying the cell seeding concentration. There was a significant increase in proteoglycan and hydroxyproline production between groups C and D. The sulphated GAG content increased significantly in the group D as compared to the other groups. The mechanical properties of the different constructs increased over time, from 9.6 G,/kPa at 14 days of 3D culture to 14.6 G,/kPa at 28 days under the same culture conditions. In this study we were able to determine that concentrations of 12,25 million cells/cm2 are needed to increase the matrix production and mechanical properties of human adult chondrocytes under static conditions. Copyright © 2008 John Wiley & Sons, Ltd. [source] Bone Morphogenetic Protein-6-loaded Chitosan Scaffolds Enhance the Osteoblastic Characteristics of MC3T3-E1 CellsARTIFICIAL ORGANS, Issue 1 2010Abdullah C. Akman Abstract The purpose of this study is to investigate the convenience of bone morphogenetic protein-6 (BMP-6)-loaded chitosan scaffolds with preosteoblastic cells for bone tissue engineering. MC3T3-E1 cells were seeded into three different groups: chitosan scaffolds, BMP-6-loaded chitosan scaffolds, and chitosan scaffolds with free BMP-6 in culture medium. Tissue-engineered constructs were characterized by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide assay, scanning electron microscopy (SEM), mineralization assay (von Kossa), alkaline phosphatase (ALP) activity, and osteocalcin (OCN) assays. BMP-6-loaded chitosan scaffolds supported proliferation of the MC3T3-E1 mouse osteogenic cells in a similar pattern as the unloaded chitosan scaffolds group and as the chitosan scaffolds with free BMP-6 group. SEM images of the cell-seeded scaffolds revealed significant acceleration of extracellular matrix synthesis in BMP-6-loaded chitosan scaffolds. Both levels of ALP and OCN were higher in BMP-6-loaded chitosan scaffold group compared with the other two groups. In addition, BMP-6-loaded scaffolds showed strong staining in mineralization assays. These findings suggest that BMP-6-loaded chitosan scaffold supports cellular functions of the osteoblastic cells; therefore, this scaffold is considered as a new promising vehicle for bone tissue engineering applications. [source] Chitosan-Based Inverse Opals: Three-Dimensional Scaffolds with Uniform Pore Structures for Cell CultureADVANCED MATERIALS, Issue 29 2009Sung-Wook Choi Chitosan inverse opal scaffolds: Three-dimensional chitosan scaffolds with an inverse opal structure have been fabricated using a cubic close packed lattice of polymer beads as the template. The scaffolds have a uniform and interconnected pore structure as well as a fibrous morphology on the wall. They can be used as a model system for in vitro studies of cell culture and as clinically practical scaffolds for tissue engineering. [source] Growth of osteoblast-like cells on biomimetic apatite-coated chitosan scaffoldsJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2008I. Manjubala Abstract Porous scaffold materials that can provide a framework for the cells to adhere, proliferate, and create extracellular matrix are considered to be suitable materials for bone regeneration. Interconnected porous chitosan scaffolds were prepared by freeze-drying method, and were mineralized by calcium and phosphate solution by double-diffusion method to form nanoapatite in chitosan matrix. The mineralized chitosan scaffold contains hydroxyapatite nanocrystals on the surface and also within the pore channels of the scaffold. To assess the effect of apatite and porosity of the scaffolds on cells, human osteoblast (SaOS-2) cells were cultured on unmineralized and mineralized chitosan scaffolds. The cell growth on the mineralized scaffolds and on the pure chitosan scaffold shows a similar growth trend. The total protein content and alkaline phosphatase enzyme activity of the cells grown on scaffolds were quantified, and were found to increase over time in mineralized scaffold after 1 and 3 weeks of culture. The electron microscopy of the cell-seeded scaffolds showed that most of the outer macropores became sealed off by a continuous layer of cells. The cells spanned around the pore wall and formed extra cellular matrix, consisting mainly of collagen in mineralized scaffolds. The hydroxyproline content also confirmed the formation of the collagen matrix by cells in mineralized scaffolds. This study demonstrated that the presence of apatite nanocrystals in chitosan scaffolds does not significantly influence the growth of cells, but does induce the formation of extracellular matrix and therefore has the potential to serve for bone tissue engineering. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008 [source] Chitosan scaffolds for in vitro buffalo embryonic stem-like cell culture: An approach to tissue engineeringJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007Wah W. Thein-Han Abstract Three-dimensional (3D) porous chitosan scaffolds are attractive candidates for tissue engineering applications. Chitosan scaffolds of 70, 88, and 95% degree of deacetylation (% DD) with the same molecular weight were developed and their properties with buffalo embryonic stem-like (ES-like) cells were investigated in vitro. Scaffolds were fabricated by freezing and lyophilization. They showed open pore structure with interconnecting pores under scanning electron microscopy (SEM). Higher % DD chitosan scaffolds had greater mechanical strength, slower degradation rate, lower water uptake ability, but similar water retention ability, when compared to lower % DD chitosan. As a strategy to tissue engineering, buffalo ES-like cells were cultured on scaffolds for 28 days. It appeared that chitosan was cytocompatible and cells proliferated well on 88 and 95% DD scaffolds. In addition, the buffalo ES-like cells maintained their pluripotency during the culture period. Furthermore, the SEM and histological study showed that the polygonal buffalo ES-like cells proliferated well and attached to the pores. This study proved that 3D biodegradable highly deacetylated chitosan scaffolds are promising candidates for ES-like cell based tissue engineering and this chitosan scaffold and ES cell based system can be used as in vitro model for subsequent clinical applications. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007 [source] Effect of cell seeding concentration on the quality of tissue engineered constructs loaded with adult human articular chondrocytesJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 1 2008Sebastian Concaro Abstract Many aspects of the process of in vitro differentiation of chondrocytes in three-dimensional (3D) scaffolds need to be further investigated. Chitosan scaffolds were produced by freeze-drying 3% w/v 90% DDA chitosan gels. The effect of the cell seeding concentration was evaluated by culturing human adult chondrocytes in chitosan scaffolds After the first passage, cells were seeded into chitosan scaffolds with a diameter of 8 mm. The final cell seeding concentration per cm3 of chitosan scaffold was: Group A, 3 × 106; Group B, 6 × 106; Group C, 12 × 106; and Group D, 25 × 106 cells. After 14 and 28 days in 3D culture, the constructs were assesed for collagen, glucosaminoglycans and DNA content. The mechanical properties of the constructs were determined using a dynamic oscillatory shear test. The histological aspect of the constructs was evaluated using the Bern score. The collagen and GAG concentration increased, varying the cell seeding concentration. There was a significant increase in proteoglycan and hydroxyproline production between groups C and D. The sulphated GAG content increased significantly in the group D as compared to the other groups. The mechanical properties of the different constructs increased over time, from 9.6 G,/kPa at 14 days of 3D culture to 14.6 G,/kPa at 28 days under the same culture conditions. In this study we were able to determine that concentrations of 12,25 million cells/cm2 are needed to increase the matrix production and mechanical properties of human adult chondrocytes under static conditions. Copyright © 2008 John Wiley & Sons, Ltd. [source] Bone Morphogenetic Protein-6-loaded Chitosan Scaffolds Enhance the Osteoblastic Characteristics of MC3T3-E1 CellsARTIFICIAL ORGANS, Issue 1 2010Abdullah C. Akman Abstract The purpose of this study is to investigate the convenience of bone morphogenetic protein-6 (BMP-6)-loaded chitosan scaffolds with preosteoblastic cells for bone tissue engineering. MC3T3-E1 cells were seeded into three different groups: chitosan scaffolds, BMP-6-loaded chitosan scaffolds, and chitosan scaffolds with free BMP-6 in culture medium. Tissue-engineered constructs were characterized by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide assay, scanning electron microscopy (SEM), mineralization assay (von Kossa), alkaline phosphatase (ALP) activity, and osteocalcin (OCN) assays. BMP-6-loaded chitosan scaffolds supported proliferation of the MC3T3-E1 mouse osteogenic cells in a similar pattern as the unloaded chitosan scaffolds group and as the chitosan scaffolds with free BMP-6 group. SEM images of the cell-seeded scaffolds revealed significant acceleration of extracellular matrix synthesis in BMP-6-loaded chitosan scaffolds. Both levels of ALP and OCN were higher in BMP-6-loaded chitosan scaffold group compared with the other two groups. In addition, BMP-6-loaded scaffolds showed strong staining in mineralization assays. These findings suggest that BMP-6-loaded chitosan scaffold supports cellular functions of the osteoblastic cells; therefore, this scaffold is considered as a new promising vehicle for bone tissue engineering applications. [source] Effect of spatial architecture on cellular colonizationBIOTECHNOLOGY & BIOENGINEERING, Issue 1 2006Yan Huang Abstract The spatial cell-material interaction remains vital issue in forming biodegradable scaffolds in Tissue Engineering. In this study, to understand the influence of spatial architecture on cellular behavior, 2D and 3D chitosan scaffolds of 50,190 kD and >310 kD MW were synthesized through air drying and controlled rate freezing/lypohilization technique, respectively. In addition, chitosan was emulsified with 19, 76, and 160 kD 50:50 poly lactide-co-glycolide (PLGA) using 1,2-Dimyristoyl-sn-Glycero-3-Phosphocholine (DMPC) as stabilizer. 2D and 3D scaffolds were formed by air drying and lyophilization as before. Tensile and compressive properties of films and scaffolds were analyzed in wet conditions at 37°C. Alterations in the cell spreading, proliferation, and cytoskeletal organization of human umbilical vein endothelial cells (HUVECs) and mouse embryonic fibroblasts (MEFs) were studied. These results showed that the formed 3D chitosan scaffolds had interconnected open pore architecture (50,200 µm size). HUVECs and MEFs had reduced spreading areas and circular morphology on 2D chitosan membranes compared with 3D chitosan scaffolds. The fluorescence photomicrographs for actin (using Alexa Fluor 488 phalloidin) and cytoplasm staining (using carboxyfluorescein diacetate-succinimidyl ester) demonstrated that the cells spread within 3D chitosan matrix. 2D and 3D emulsified chitosan and chitosan/PLGA scaffolds reduced the spreading of HUVECs and MEFs even further. Proliferation results, analyzed via MTT-Formazan assay and BrdU uptake assay, correlated with the spreading characteristics. The reductions in cell spreading area on emulsified surfaces were not detrimental to the viability and endocytic activity but to proliferation. The observed alterations in cellular colonization are in part due to the substrate stiffness and surface topography. In summary, these results suggest a significant influence of spatial architecture on cellular colonization. © 2005 Wiley Periodicals, Inc. [source] |