The Experts below are selected from a list of 189 Experts worldwide ranked by ideXlab platform
Pierre Mainilvarlet - One of the best experts on this subject based on the ideXlab platform.
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immunophenotypic changes of human articular chondrocytes during Monolayer Culture reflect bona fide dedifferentiation rather than amplification of progenitor cells
Journal of Cellular Physiology, 2008Co-Authors: Jose Diazromero, Shawn P Grogan, Dobrila Nesic, Paul F Heini, Pierre MainilvarletAbstract:In this study, a time-course comparison of human articular chondrocytes (HAC) and bone marrow-derived mesenchymal stem cells (MSC) immunophenotype was performed in order to determine similarities/differences between both cell types during Monolayer Culture, and to identify HAC surface markers indicative of dedifferentiation. Our results show that dedifferentiated HAC can be distinguished from MSC by combining CD14, CD90, and CD105 expression, with dedifferentiated HAC being CD14+/CD90bright/CD105dim and MSC being CD14-/CD90dim/CD105bright. Surface markers on MSC showed little variation during the Culture, whereas HAC showed upregulation of CD90, CD166, CD49c, CD44, CD10, CD26, CD49e, CD151, CD51/61, and CD81, and downregulation of CD49a, CD54, and CD14. Thus, dedifferentiated HAC appear as a bona fide cell population rather than a small population of MSC amplified during Monolayer Culture. While most of the HAC surface markers showed major changes at the beginning of the Culture period (Passage 1-2), CD26 was upregulated and CD49a downregulated at later stages of the Culture (Passage 3-4). To correlate changes in HAC surface markers with changes in extracellular matrix gene expression during Monolayer Culture, CD14 and CD90 mRNA levels were combined into a new differentiation index and compared with the established differentiation indices based on the ratios of mRNA levels of collagen type II to I (COL2/COL1) and of aggrecan to versican (AGG/VER). A correlation of CD14/CD90 ratio at the mRNA and protein level with the AGG/VER ratio during HAC dedifferentiation in Monolayer Culture validated CD14/CD90 as a new membrane and mRNA based HAC differentiation index.
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immunophenotypic analysis of human articular chondrocytes changes in surface markers associated with cell expansion in Monolayer Culture
Journal of Cellular Physiology, 2005Co-Authors: Jose Diazromero, Jean Philippe Gaillard, Shawn P Grogan, Dobrila Nesic, Thomas Trub, Pierre MainilvarletAbstract:Cartilage tissue engineering relies on in vitro expansion of primary chondrocytes. Monolayer is the chosen Culture model for chondrocyte expansion because in this system the proliferative capacity of chondrocytes is substantially higher compared to non-adherent systems. However, human articular chondrocytes (HACs) Cultured as Monolayers undergo changes in phenotype and gene expression known as “dedifferentiation.” To gain a better understanding of the cellular mechanisms involved in the dedifferentiation process, our research focused on the characterization of the surface molecule phenotype of HACs in Monolayer Culture. Adult HACs were isolated by enzymatic digestion of cartilage samples obtained post-mortem. HACs Cultured in Monolayer for different time periods were analyzed by flow cytometry for the expression of cell surface markers with a panel of 52 antibodies. Our results show that HACs express surface molecules belonging to different categories: integrins and other adhesion molecules (CD49a, CD49b, CD49c, CD49e, CD49f, CD51/61, CD54, CD106, CD166, CD58, CD44), tetraspanins (CD9, CD63, CD81, CD82, CD151), receptors (CD105, CD119, CD130, CD140a, CD221, CD95, CD120a, CD71, CD14), ectoenzymes (CD10, CD26), and other surface molecules (CD90, CD99). Moreover, differential expression of certain markers in Monolayer Culture was identified. Up-regulation of markers on HACs regarded as distinctive for mesenchymal stem cells (CD10, CD90, CD105, CD166) during Monolayer Culture suggested that dedifferentiation leads to reversion to a primitive phenotype. This study contributes to the definition of HAC phenotype, and provides new potential markers to characterize chondrocyte differentiation stage in the context of tissue engineering applications. © 2004 Wiley-Liss, Inc.
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immunophenotypic analysis of human articular chondrocytes changes in surface markers associated with cell expansion in Monolayer Culture
Journal of Cellular Physiology, 2005Co-Authors: Jose Diazromero, Jean Philippe Gaillard, Shawn P Grogan, Dobrila Nesic, Thomas Trub, Pierre MainilvarletAbstract:Cartilage tissue engineering relies on in vitro expansion of primary chondrocytes. Monolayer is the chosen Culture model for chondrocyte expansion because in this system the proliferative capacity of chondrocytes is substantially higher compared to non-adherent systems. However, human articular chondrocytes (HACs) Cultured as Monolayers undergo changes in phenotype and gene expression known as "dedifferentiation." To gain a better understanding of the cellular mechanisms involved in the dedifferentiation process, our research focused on the characterization of the surface molecule phenotype of HACs in Monolayer Culture. Adult HACs were isolated by enzymatic digestion of cartilage samples obtained post-mortem. HACs Cultured in Monolayer for different time periods were analyzed by flow cytometry for the expression of cell surface markers with a panel of 52 antibodies. Our results show that HACs express surface molecules belonging to different categories: integrins and other adhesion molecules (CD49a, CD49b, CD49c, CD49e, CD49f, CD51/61, CD54, CD106, CD166, CD58, CD44), tetraspanins (CD9, CD63, CD81, CD82, CD151), receptors (CD105, CD119, CD130, CD140a, CD221, CD95, CD120a, CD71, CD14), ectoenzymes (CD10, CD26), and other surface molecules (CD90, CD99). Moreover, differential expression of certain markers in Monolayer Culture was identified. Up-regulation of markers on HACs regarded as distinctive for mesenchymal stem cells (CD10, CD90, CD105, CD166) during Monolayer Culture suggested that dedifferentiation leads to reversion to a primitive phenotype. This study contributes to the definition of HAC phenotype, and provides new potential markers to characterize chondrocyte differentiation stage in the context of tissue engineering applications.
Jose Diazromero - One of the best experts on this subject based on the ideXlab platform.
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immunophenotypic changes of human articular chondrocytes during Monolayer Culture reflect bona fide dedifferentiation rather than amplification of progenitor cells
Journal of Cellular Physiology, 2008Co-Authors: Jose Diazromero, Shawn P Grogan, Dobrila Nesic, Paul F Heini, Pierre MainilvarletAbstract:In this study, a time-course comparison of human articular chondrocytes (HAC) and bone marrow-derived mesenchymal stem cells (MSC) immunophenotype was performed in order to determine similarities/differences between both cell types during Monolayer Culture, and to identify HAC surface markers indicative of dedifferentiation. Our results show that dedifferentiated HAC can be distinguished from MSC by combining CD14, CD90, and CD105 expression, with dedifferentiated HAC being CD14+/CD90bright/CD105dim and MSC being CD14-/CD90dim/CD105bright. Surface markers on MSC showed little variation during the Culture, whereas HAC showed upregulation of CD90, CD166, CD49c, CD44, CD10, CD26, CD49e, CD151, CD51/61, and CD81, and downregulation of CD49a, CD54, and CD14. Thus, dedifferentiated HAC appear as a bona fide cell population rather than a small population of MSC amplified during Monolayer Culture. While most of the HAC surface markers showed major changes at the beginning of the Culture period (Passage 1-2), CD26 was upregulated and CD49a downregulated at later stages of the Culture (Passage 3-4). To correlate changes in HAC surface markers with changes in extracellular matrix gene expression during Monolayer Culture, CD14 and CD90 mRNA levels were combined into a new differentiation index and compared with the established differentiation indices based on the ratios of mRNA levels of collagen type II to I (COL2/COL1) and of aggrecan to versican (AGG/VER). A correlation of CD14/CD90 ratio at the mRNA and protein level with the AGG/VER ratio during HAC dedifferentiation in Monolayer Culture validated CD14/CD90 as a new membrane and mRNA based HAC differentiation index.
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immunophenotypic analysis of human articular chondrocytes changes in surface markers associated with cell expansion in Monolayer Culture
Journal of Cellular Physiology, 2005Co-Authors: Jose Diazromero, Jean Philippe Gaillard, Shawn P Grogan, Dobrila Nesic, Thomas Trub, Pierre MainilvarletAbstract:Cartilage tissue engineering relies on in vitro expansion of primary chondrocytes. Monolayer is the chosen Culture model for chondrocyte expansion because in this system the proliferative capacity of chondrocytes is substantially higher compared to non-adherent systems. However, human articular chondrocytes (HACs) Cultured as Monolayers undergo changes in phenotype and gene expression known as “dedifferentiation.” To gain a better understanding of the cellular mechanisms involved in the dedifferentiation process, our research focused on the characterization of the surface molecule phenotype of HACs in Monolayer Culture. Adult HACs were isolated by enzymatic digestion of cartilage samples obtained post-mortem. HACs Cultured in Monolayer for different time periods were analyzed by flow cytometry for the expression of cell surface markers with a panel of 52 antibodies. Our results show that HACs express surface molecules belonging to different categories: integrins and other adhesion molecules (CD49a, CD49b, CD49c, CD49e, CD49f, CD51/61, CD54, CD106, CD166, CD58, CD44), tetraspanins (CD9, CD63, CD81, CD82, CD151), receptors (CD105, CD119, CD130, CD140a, CD221, CD95, CD120a, CD71, CD14), ectoenzymes (CD10, CD26), and other surface molecules (CD90, CD99). Moreover, differential expression of certain markers in Monolayer Culture was identified. Up-regulation of markers on HACs regarded as distinctive for mesenchymal stem cells (CD10, CD90, CD105, CD166) during Monolayer Culture suggested that dedifferentiation leads to reversion to a primitive phenotype. This study contributes to the definition of HAC phenotype, and provides new potential markers to characterize chondrocyte differentiation stage in the context of tissue engineering applications. © 2004 Wiley-Liss, Inc.
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immunophenotypic analysis of human articular chondrocytes changes in surface markers associated with cell expansion in Monolayer Culture
Journal of Cellular Physiology, 2005Co-Authors: Jose Diazromero, Jean Philippe Gaillard, Shawn P Grogan, Dobrila Nesic, Thomas Trub, Pierre MainilvarletAbstract:Cartilage tissue engineering relies on in vitro expansion of primary chondrocytes. Monolayer is the chosen Culture model for chondrocyte expansion because in this system the proliferative capacity of chondrocytes is substantially higher compared to non-adherent systems. However, human articular chondrocytes (HACs) Cultured as Monolayers undergo changes in phenotype and gene expression known as "dedifferentiation." To gain a better understanding of the cellular mechanisms involved in the dedifferentiation process, our research focused on the characterization of the surface molecule phenotype of HACs in Monolayer Culture. Adult HACs were isolated by enzymatic digestion of cartilage samples obtained post-mortem. HACs Cultured in Monolayer for different time periods were analyzed by flow cytometry for the expression of cell surface markers with a panel of 52 antibodies. Our results show that HACs express surface molecules belonging to different categories: integrins and other adhesion molecules (CD49a, CD49b, CD49c, CD49e, CD49f, CD51/61, CD54, CD106, CD166, CD58, CD44), tetraspanins (CD9, CD63, CD81, CD82, CD151), receptors (CD105, CD119, CD130, CD140a, CD221, CD95, CD120a, CD71, CD14), ectoenzymes (CD10, CD26), and other surface molecules (CD90, CD99). Moreover, differential expression of certain markers in Monolayer Culture was identified. Up-regulation of markers on HACs regarded as distinctive for mesenchymal stem cells (CD10, CD90, CD105, CD166) during Monolayer Culture suggested that dedifferentiation leads to reversion to a primitive phenotype. This study contributes to the definition of HAC phenotype, and provides new potential markers to characterize chondrocyte differentiation stage in the context of tissue engineering applications.
Mehdi Shakibaei - One of the best experts on this subject based on the ideXlab platform.
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integrin expression and collagen type ii implicated in maintenance of chondrocyte shape in Monolayer Culture an immunomorphological study
Cell Biology International, 1997Co-Authors: Mehdi Shakibaei, P De Souza, H J MerkerAbstract:Chondrocytes grown in Monolayer Culture at low density, with serum added, either dedifferentiate after several days whereby their cell shape or they are overgrown by fibroblast-like cells. The aim of this study was to optimize the cultivation of chondrocytes in Monolayer Culture and to slow down their transformation or their overgrowth by fibroblast-like cells. For this purpose freshly isolated chondrocytes of cartilage anlagen from 17-day-old mouse embryos were grown on plastic or collagen type II-coated substrates. With this model: (a) chondrocytes grown on plastic substrates had almost completely changed to fibroblast-like cells after 5 days in Culture. (b) When grown on collagen type II, the chondrocytes maintained their round phenotype for more than 2 weeks in Culture. (c) Immunomorphological investigations showed that chondrocytes produce collagen type II and fibronectin and express specific surface receptors (integrins of the beta 1-group) on the membrane from day 1 until the end of the Culture period when grown on collagen type II. (d) Treatment with beta 1-integrin antibodies clearly reduces chondrocyte adhesion on collagen type II by about 70%. Hence, these data indicate that the most probable influence of collagen type II on cellular behaviour depends on the integrins participating in a chondrocyte-collagen type II interaction, and this model represents a pure chondrocyte Culture which allows cell growth for an extended period.
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Integrin expression on epiphyseal mouse chondrocytes in Monolayer Culture.
Histology and histopathology, 1995Co-Authors: Mehdi ShakibaeiAbstract:The expression of al-, a3-, av- and a5B1- integrins and their specific ligand binding were investigated in Monolayer Cultures of chondrocytes from 17-day-old mouse embryos using morphological and immunomorphological methods. After a 1-day Culture period av-, a3- and a5B1-integrins were observed on these cells. Immunoelectronmicroscopic investigation revealed localization predominantly in the contact areas with extracellular structures on the cell surface. alintegrin could not be demonstrated on chondrocytes. After a 5-day Culture period the number of fibroblastlike cells with a l - , av- and a5B1-integrins had increased. a3-integrin was hardly recognizable on these cells. Collagen type 1 and fibronectin could be shown as ligands on the cell surface. The number of chondrocytes with collagen type 11 on their surface continuously decreased. a3-integrin is obviously responsible for the binding of collagen type 11, and al-integrin for the binding of collagen type 1. Therefore, it can be concluded that the changes of chondrocytes to fibroblast- like cells in Monolayer Culture are accompanied by changes of integrin genes.
Megumu K Saito - One of the best experts on this subject based on the ideXlab platform.
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a novel serum free Monolayer Culture for orderly hematopoietic differentiation of human pluripotent cells via mesodermal progenitors
PLOS ONE, 2011Co-Authors: Akira Niwa, Toshio Heike, Katsutsugu Umeda, Koichi Oshima, Itaru Kato, Hiromi Sakai, Hirofumi Suemori, Tatsutoshi Nakahata, Megumu K SaitoAbstract:Elucidating the in vitro differentiation of human embryonic stem (ES) and induced pluripotent stem (iPS) cells is important for understanding both normal and pathological hematopoietic development in vivo. For this purpose, a robust and simple hematopoietic differentiation system that can faithfully trace in vivo hematopoiesis is necessary. In this study, we established a novel serum-free Monolayer Culture that can trace the in vivo hematopoietic pathway from ES/iPS cells to functional definitive blood cells via mesodermal progenitors. Stepwise tuning of exogenous cytokine cocktails induced the hematopoietic mesodermal progenitors via primitive streak cells. These progenitors were then differentiated into various cell lineages depending on the hematopoietic cytokines present. Moreover, single cell deposition assay revealed that common bipotential hemoangiogenic progenitors were induced in our Culture. Our system provides a new, robust, and simple method for investigating the mechanisms of mesodermal and hematopoietic differentiation.
Shawn P Grogan - One of the best experts on this subject based on the ideXlab platform.
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immunophenotypic changes of human articular chondrocytes during Monolayer Culture reflect bona fide dedifferentiation rather than amplification of progenitor cells
Journal of Cellular Physiology, 2008Co-Authors: Jose Diazromero, Shawn P Grogan, Dobrila Nesic, Paul F Heini, Pierre MainilvarletAbstract:In this study, a time-course comparison of human articular chondrocytes (HAC) and bone marrow-derived mesenchymal stem cells (MSC) immunophenotype was performed in order to determine similarities/differences between both cell types during Monolayer Culture, and to identify HAC surface markers indicative of dedifferentiation. Our results show that dedifferentiated HAC can be distinguished from MSC by combining CD14, CD90, and CD105 expression, with dedifferentiated HAC being CD14+/CD90bright/CD105dim and MSC being CD14-/CD90dim/CD105bright. Surface markers on MSC showed little variation during the Culture, whereas HAC showed upregulation of CD90, CD166, CD49c, CD44, CD10, CD26, CD49e, CD151, CD51/61, and CD81, and downregulation of CD49a, CD54, and CD14. Thus, dedifferentiated HAC appear as a bona fide cell population rather than a small population of MSC amplified during Monolayer Culture. While most of the HAC surface markers showed major changes at the beginning of the Culture period (Passage 1-2), CD26 was upregulated and CD49a downregulated at later stages of the Culture (Passage 3-4). To correlate changes in HAC surface markers with changes in extracellular matrix gene expression during Monolayer Culture, CD14 and CD90 mRNA levels were combined into a new differentiation index and compared with the established differentiation indices based on the ratios of mRNA levels of collagen type II to I (COL2/COL1) and of aggrecan to versican (AGG/VER). A correlation of CD14/CD90 ratio at the mRNA and protein level with the AGG/VER ratio during HAC dedifferentiation in Monolayer Culture validated CD14/CD90 as a new membrane and mRNA based HAC differentiation index.
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immunophenotypic analysis of human articular chondrocytes changes in surface markers associated with cell expansion in Monolayer Culture
Journal of Cellular Physiology, 2005Co-Authors: Jose Diazromero, Jean Philippe Gaillard, Shawn P Grogan, Dobrila Nesic, Thomas Trub, Pierre MainilvarletAbstract:Cartilage tissue engineering relies on in vitro expansion of primary chondrocytes. Monolayer is the chosen Culture model for chondrocyte expansion because in this system the proliferative capacity of chondrocytes is substantially higher compared to non-adherent systems. However, human articular chondrocytes (HACs) Cultured as Monolayers undergo changes in phenotype and gene expression known as “dedifferentiation.” To gain a better understanding of the cellular mechanisms involved in the dedifferentiation process, our research focused on the characterization of the surface molecule phenotype of HACs in Monolayer Culture. Adult HACs were isolated by enzymatic digestion of cartilage samples obtained post-mortem. HACs Cultured in Monolayer for different time periods were analyzed by flow cytometry for the expression of cell surface markers with a panel of 52 antibodies. Our results show that HACs express surface molecules belonging to different categories: integrins and other adhesion molecules (CD49a, CD49b, CD49c, CD49e, CD49f, CD51/61, CD54, CD106, CD166, CD58, CD44), tetraspanins (CD9, CD63, CD81, CD82, CD151), receptors (CD105, CD119, CD130, CD140a, CD221, CD95, CD120a, CD71, CD14), ectoenzymes (CD10, CD26), and other surface molecules (CD90, CD99). Moreover, differential expression of certain markers in Monolayer Culture was identified. Up-regulation of markers on HACs regarded as distinctive for mesenchymal stem cells (CD10, CD90, CD105, CD166) during Monolayer Culture suggested that dedifferentiation leads to reversion to a primitive phenotype. This study contributes to the definition of HAC phenotype, and provides new potential markers to characterize chondrocyte differentiation stage in the context of tissue engineering applications. © 2004 Wiley-Liss, Inc.
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immunophenotypic analysis of human articular chondrocytes changes in surface markers associated with cell expansion in Monolayer Culture
Journal of Cellular Physiology, 2005Co-Authors: Jose Diazromero, Jean Philippe Gaillard, Shawn P Grogan, Dobrila Nesic, Thomas Trub, Pierre MainilvarletAbstract:Cartilage tissue engineering relies on in vitro expansion of primary chondrocytes. Monolayer is the chosen Culture model for chondrocyte expansion because in this system the proliferative capacity of chondrocytes is substantially higher compared to non-adherent systems. However, human articular chondrocytes (HACs) Cultured as Monolayers undergo changes in phenotype and gene expression known as "dedifferentiation." To gain a better understanding of the cellular mechanisms involved in the dedifferentiation process, our research focused on the characterization of the surface molecule phenotype of HACs in Monolayer Culture. Adult HACs were isolated by enzymatic digestion of cartilage samples obtained post-mortem. HACs Cultured in Monolayer for different time periods were analyzed by flow cytometry for the expression of cell surface markers with a panel of 52 antibodies. Our results show that HACs express surface molecules belonging to different categories: integrins and other adhesion molecules (CD49a, CD49b, CD49c, CD49e, CD49f, CD51/61, CD54, CD106, CD166, CD58, CD44), tetraspanins (CD9, CD63, CD81, CD82, CD151), receptors (CD105, CD119, CD130, CD140a, CD221, CD95, CD120a, CD71, CD14), ectoenzymes (CD10, CD26), and other surface molecules (CD90, CD99). Moreover, differential expression of certain markers in Monolayer Culture was identified. Up-regulation of markers on HACs regarded as distinctive for mesenchymal stem cells (CD10, CD90, CD105, CD166) during Monolayer Culture suggested that dedifferentiation leads to reversion to a primitive phenotype. This study contributes to the definition of HAC phenotype, and provides new potential markers to characterize chondrocyte differentiation stage in the context of tissue engineering applications.