The Experts below are selected from a list of 30489 Experts worldwide ranked by ideXlab platform
Seho Park - One of the best experts on this subject based on the ideXlab platform.
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2b4 cd244 is required for optimal activation of inkt cells through cd48 ligation on inkt cells irc8p 489
Journal of Immunology, 2014Co-Authors: Jung Hoon Shin, Seho ParkAbstract:iNKT cells are a specialized subset of T cells which can modulate immune responses in a diverse way and require fine regulation of their own reactivity. 2B4 (CD244) is a member of the SLAM family molecules and acts as both inhibitory and activating receptor in murine CD8+ T and NK cells depending on relative expression levels of CD48 on target cells, whereas human 2B4 is known to be an activating molecule. Although iNKT cells also express 2B4, the function of 2B4 on iNKT cells remains largely unknown. Here, we report that the optimal activation of iNKT cells requires 2B4. iNKT cells in 2B4 knock-out (KO) mice showed impaired activity and the symptoms of Con-A induced hepatitis were substantially weaker in 2B4 KO mice than those in wild type mice. 2B4 on iNKT cells also required CD48 engagement to exert its effect. Strikingly however, we found that CD48 providers were not necessarily target cells. These results suggest that 2B4 on iNKT cells is required for the optimal stimulation of iNKT cells and 2B4/CD48 Interaction of iNKT cells can be mediated through homotypic Cell-Cell Interaction
Gabor Forgacs - One of the best experts on this subject based on the ideXlab platform.
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Scaffold-free vascular tissue engineering using bioprinting
Biomaterials, 2009Co-Authors: Cyrille Norotte, Francois S. Marga, Laura E. Niklason, Gabor ForgacsAbstract:Current limitations of exogenous scaffolds or extracellular matrix based materials have underlined the need for alternative tissue-engineering solutions. Scaffolds may elicit adverse host responses and interfere with direct Cell-Cell Interaction, as well as assembly and alignment of cell-produced ECM. Thus, fabrication techniques for production of scaffold-free engineered tissue constructs have recently emerged. Here we report on a fully biological self-assembly approach, which we implement through a rapid prototyping bioprinting method for scaffold-free small diameter vascular reconstruction. Various vascular cell types, including smooth muscle cells and fibroblasts, were aggregated into discrete units, either multicellular spheroids or cylinders of controllable diameter (300-500 μm). These were printed layer-by-layer concomitantly with agarose rods, used here as a molding template. The post-printing fusion of the discrete units resulted in single- and double-layered small diameter vascular tubes (OD ranging from 0.9 to 2.5 mm). A unique aspect of the method is the ability to engineer vessels of distinct shapes and hierarchical trees that combine tubes of distinct diameters. The technique is quick and easily scalable.
Matsuhiko Nishizawa - One of the best experts on this subject based on the ideXlab platform.
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Generation of Patterned Cell Co-Cultures in Silicone Tubing Using a Microelectrode Technique and Electrostatic Assembly
2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2007Co-Authors: Hirokazu Kaji, Soichiro Sekine, Masahiko Hashimoto, Takeaki Kawashima, Matsuhiko NishizawaAbstract:We report a method for producing patterned cell adhesion inside silicone tubing. A platinum needle microelectrode was inserted through the wall of the tubing and an oxidizing agent electrochemically generated at the inserted electrode. This agent caused local detachment of the anti-biofouling heparin layer from the inner surface of the tubing. The cell-adhesive protein fibronectin selectively adsorbed onto the newly exposed surface, making it possible to initiate a localized cell culture. The electrode could be readily set in place without breaking the tubular structure and, importantly, almost no culture solution leaked from the electrode insertion site after the electrode was removed. Ionic adsorption of poly-L-lysine at the tubular region retaining a heparin coating was used to switch the heparin surface from cell-repellent to cell-adhesive, thereby facilitating the adhesion of a second cell type. The combination of the electrode-based technique with electrostatic deposition enabled the formation of patterned co-cultures within the semi-closed tubular structure. The controlled co-cultures inside the elastic tubing should be of value for Cell-Cell Interaction studies following application of chemical or mechanical stimuli and for tissue engineering-based bioreactors.
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Generation of Patterned Cell Co-Cultures inside Tubular Structure Using Electrochemical Biolithography and Electrostatic Assembly
2007 International Symposium on Micro-NanoMechatronics and Human Science, 2007Co-Authors: Hirokazu Kaji, Soichiro Sekine, Takashi Abe, Matsuhiko NishizawaAbstract:We report a method for producing patterned cell co-cultures inside silicone tubing. A platinum needle microelectrode was inserted through the wall of the tubing and an oxidizing agent electrochemically generated at the inserted electrode. This agent caused local detachment of the anti-biofouling heparin layer from the inner surface of the tubing. The cell-adhesive protein fibronectin selectively adsorbed onto the newly exposed surface, making it possible to initiate a localized cell culture. The electrode could be readily set in place without breaking the tubular structure and, importantly, almost no culture solution leaked from the electrode insertion site after the electrode was removed. Ionic adsorption of poly-L-lysine at the tubular region retaining a heparin coating was used to switch the heparin surface from cell-repellent to cell-adhesive, thereby facilitating the adhesion of a second cell type. The combination of the electrode-based technique with electrostatic deposition enabled the formation of patterned co-cultures within the semi-closed tubular structure. The controlled co-cultures inside the elastic tubing should be of value for Cell-Cell Interaction studies following application of chemical or mechanical stimuli and for tissue engineering-based bioreactors.
Jung Hoon Shin - One of the best experts on this subject based on the ideXlab platform.
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2b4 cd244 is required for optimal activation of inkt cells through cd48 ligation on inkt cells irc8p 489
Journal of Immunology, 2014Co-Authors: Jung Hoon Shin, Seho ParkAbstract:iNKT cells are a specialized subset of T cells which can modulate immune responses in a diverse way and require fine regulation of their own reactivity. 2B4 (CD244) is a member of the SLAM family molecules and acts as both inhibitory and activating receptor in murine CD8+ T and NK cells depending on relative expression levels of CD48 on target cells, whereas human 2B4 is known to be an activating molecule. Although iNKT cells also express 2B4, the function of 2B4 on iNKT cells remains largely unknown. Here, we report that the optimal activation of iNKT cells requires 2B4. iNKT cells in 2B4 knock-out (KO) mice showed impaired activity and the symptoms of Con-A induced hepatitis were substantially weaker in 2B4 KO mice than those in wild type mice. 2B4 on iNKT cells also required CD48 engagement to exert its effect. Strikingly however, we found that CD48 providers were not necessarily target cells. These results suggest that 2B4 on iNKT cells is required for the optimal stimulation of iNKT cells and 2B4/CD48 Interaction of iNKT cells can be mediated through homotypic Cell-Cell Interaction
Cyrille Norotte - One of the best experts on this subject based on the ideXlab platform.
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Scaffold-free vascular tissue engineering using bioprinting
Biomaterials, 2009Co-Authors: Cyrille Norotte, Francois S. Marga, Laura E. Niklason, Gabor ForgacsAbstract:Current limitations of exogenous scaffolds or extracellular matrix based materials have underlined the need for alternative tissue-engineering solutions. Scaffolds may elicit adverse host responses and interfere with direct Cell-Cell Interaction, as well as assembly and alignment of cell-produced ECM. Thus, fabrication techniques for production of scaffold-free engineered tissue constructs have recently emerged. Here we report on a fully biological self-assembly approach, which we implement through a rapid prototyping bioprinting method for scaffold-free small diameter vascular reconstruction. Various vascular cell types, including smooth muscle cells and fibroblasts, were aggregated into discrete units, either multicellular spheroids or cylinders of controllable diameter (300-500 μm). These were printed layer-by-layer concomitantly with agarose rods, used here as a molding template. The post-printing fusion of the discrete units resulted in single- and double-layered small diameter vascular tubes (OD ranging from 0.9 to 2.5 mm). A unique aspect of the method is the ability to engineer vessels of distinct shapes and hierarchical trees that combine tubes of distinct diameters. The technique is quick and easily scalable.