The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
Shu Chien - One of the best experts on this subject based on the ideXlab platform.
-
shear stress inhibits adhesion molecule expression in vascular endothelial cells induced by Coculture with smooth muscle cells
Blood, 2003Co-Authors: Jengjiann Chiu, Lijing Chen, Leuwei Lo, Shunichi Usami, Shu ChienAbstract:Vascular endothelial cells (ECs), which exist in close proximity to vascular smooth muscle cells (SMCs), are constantly subjected to blood flow–induced shear stress. Although the effect of shear stress on endothelial biology has been extensively studied, the influence of SMCs on endothelial response to shear stress remains largely unexplored. We examined the potential role of SMCs in regulating the shear stress–induced gene expression in ECs, using a parallel-plate Coculture flow system in which these 2 types of cells were separated by a porous membrane. In this Coculture system, SMCs tended to orient perpendicularly to the flow direction, whereas the ECs were elongated and aligned with the flow direction. Under static conditions, Coculture with SMCs induced EC gene expression of intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1), and E-selectin, while attenuating EC gene expression of endothelial nitric oxide synthase (eNOS). Shear stress significantly inhibited SMC-induced adhesion molecule gene expression. These EC responses under static and shear conditions were not observed in the absence of close communication between ECs and SMCs, and they were also not observed when ECs were Cocultured with fibroblasts instead of SMCs. Our findings indicate that under static conditions, Coculture with SMCs induces ICAM-1, VCAM-1, and E-selectin gene expression in ECs. These Coculture effects are inhibited by shear stress and require specific interaction between ECs and SMCs in close contact.
Hideto Kaba - One of the best experts on this subject based on the ideXlab platform.
-
accessory olfactory bulb neurons are required for maintenance but not induction of v2r vomeronasal receptor gene expression in vitro
Neuroscience Letters, 2011Co-Authors: Kazuyo Muramoto, Kimiko Haginoyamagishi, Keiichi Tonosaki, Hideto KabaAbstract:Abstract Many mammals detect pheromones by a sensory organ, the vomeronasal organ (VNO). In a previous study using immunoblot and immunocytochemical analyses, we reported that Cocultures of VNOs with accessory olfactory bulb (AOB) neurons resulted in the maturation of vomeronasal sensory neurons (VSNs) and a greater expression of V2R family vomeronasal receptors than cultures with VNO alone. To further characterize the V2R expression, we here investigated the time course of the expression of V2R mRNA in the presence or absence of AOB neurons using RT-PCR analysis. The expression of V2R mRNA was already detectable not only in the VNO Cocultured with AOB neurons for 3 days in Coculture but also in the VNO cultured alone for the same number of days. However, the expression of V2R mRNA in the VNO cultured alone was remarkably decreased during the additional culture period, although that in the Cocultured VNO showed sustained expression. Moreover, the application of 2 μM TTX to the Cocultured VNO resulted in a marked decrease in the V2R mRNA expression to a level equal to that in the VNO cultured alone for 14 days in Coculture. Our previous working hypothesis was that the expression of V2Rs in VSNs was induced by interacting with AOB neurons. However, the present results suggest that the receptor expression in VSNs is independent of the interaction with AOB neurons in the early developmental stage, but is maintained by the active interaction with AOB neurons.
-
Target regulation of V2R expression and functional maturation in vomeronasal sensory neurons in vitro.
European Journal of Neuroscience, 2007Co-Authors: Kazuyo Muramoto, Mitsuhiro Hashimoto, Hideto KabaAbstract:Vomeronasal receptors from the V1R and V2R gene families mediate the detection of chemical stimuli such as pheromones via the vomeronasal organ (VNO). The differential expression of vomeronasal receptors might contribute in part to a variety of pheromonal effects, which are different sexually, developmentally and even individually. However, little is known about the mechanisms controlling vomeronasal receptor expression. Cultured vomeronasal sensory neurons (VSNs) bear phenotypic resemblance to the intact VNO but they remain immature. Because indices of VSN maturation are increased by Coculture with the target cells for VSNs, accessory olfactory bulb (AOB) neurons, AOB neurons may regulate vomeronasal receptor expression and functional maturation in VSNs. To test this hypothesis, we examined the expression of V2R-type vomeronasal receptors (VR1 and VR4) and chemosensory responsiveness in VNOs Cocultured with AOB neurons. Immunoblot and immunocytochemical analysis revealed that the Coculture of VNOs with AOB neurons resulted in a greater expression of VR1 and VR4 after 10 days than VNOs cultured alone. Moreover, calcium imaging analysis showed that Cocultured VNOs responded to urine components applied iontophoretically into their cavities with a time course similar to the V2R expression, in contrast to singly cultured VNOs that displayed no response. These results demonstrate that AOB neurons induce the expression of vomeronasal receptors in VSNs, allowing them to function.
Ruth Knuechel - One of the best experts on this subject based on the ideXlab platform.
-
a heterologous 3 d Coculture model of breast tumor cells and fibroblasts to study tumor associated fibroblast differentiation
Experimental Cell Research, 2001Co-Authors: Leoni A Kunzschughart, Paula Heyder, Josef Schroeder, Ruth KnuechelAbstract:Abstract The objective of our study was to establish spheroid Cocultures as a valid 3-D in vitro model mimicking tumor-fibroblast interactions in scirrhous breast tumors. The experimental setup was designed to verify if in Cocultures (a) adherence and migration reflect the invasive potential of breast tumor cells, (b) breast tumor cells induce tumor-associated fibroblast differentiation, and (c) tumor-derived fibroblasts better reflect the in vivo situation than normal skin fibroblasts. Only one (SK-BR-3) out of five tumor cell types showed extensive fibroblast infiltration, MCF-7 cells frequently invaded fibroblast spheroids; BT474, T47D, and ZR-75-1 were noninvasive. While tumor cell invasion was independent of fibroblast origin, tumor-associated myofibroblast differentiation defined by α-SMA expression was demonstrated for tumor-derived but not normal skin fibroblasts in Coculture indicating that (a) tumor cell invasion and myofibroblast differentiation are autonomous processes and (b) Cocultures with tumor-derived fibroblasts resemble advanced stages of desmoplastic carcinomas while Cocultures with normal skin fibroblasts rather reflect the early tumor development. The latter is also implied by fibroblast-associated alterations in tumor cell morphology and ECM distribution in the system. By using RNA arbitrarily primed PCR and cells isolated from Cocultures by fluorescence-activated and magnetic cell separation, peripheral myelin protein PMP22/SR13 has been identified as a novel candidate with potential relevance in the interaction between tumor cell and normal fibroblast since PMP22 mRNA was significantly reduced in normal skin fibroblasts in Coculture with BT474 cells.
Chul Soo Shin - One of the best experts on this subject based on the ideXlab platform.
-
Analysis of the morphologic changes of Monascus sp. J101 cells Cocultured with Saccharomyces cerevisiae.
Fems Microbiology Letters, 2000Co-Authors: Chul Soo ShinAbstract:Changes in cell life cycle and intracellular structure of Monascus sp. J101 by Coculture with Saccharomyces cerevisiae were investigated. Cocultured Monascus cells showed accelerated cell growth and reproduction. Production of asexual and sexual spores was used as an efficient method of cell proliferation. Formation of meiotic (sexual) spores was more frequently observed in the Cocultured Monascus cells. The interior structure of a Cocultured cell was characterized by increased numbers and sizes of vacuoles. The vacuoles probably serve as repositories for pigment storage. Pigments produced by the Cocultured Monascus cells were more hydrophobic than pigments produced by control cells with no Coculture.
-
Physiological analysis on novel Coculture of Monascus sp. J101 with Saccharomyces cerevisiae
Fems Microbiology Letters, 2000Co-Authors: Chul Soo ShinAbstract:During the fermentation process of Monascus J101, Coculture with Saccharomyces cerevisiae culture filtrate stimulated the formation of reproductive spores, which subsequently resulted in accelerated Monascus cell reproduction and proliferation. Protein kinase C activity was also detected. Chitinase (EC 3.2.1.14), a 120-kDa secretory protein, was purified from the S. cerevisiae culture filtrate as the effector. Monascus cells Cocultured with a S. cerevisiae culture filtrate contained approximately four times more total lipids (mainly linoleic and oleic acid) than Monascus cells without Coculture. Addition of exogenous fatty acids only contributed to an increase in cell mass. There was no effect on spore formation or pigment production. There were significant changes in patterns and amounts of expressed proteins in Cocultured Monascus cells compared to control cells with no Coculture.
Jengjiann Chiu - One of the best experts on this subject based on the ideXlab platform.
-
shear stress inhibits adhesion molecule expression in vascular endothelial cells induced by Coculture with smooth muscle cells
Blood, 2003Co-Authors: Jengjiann Chiu, Lijing Chen, Leuwei Lo, Shunichi Usami, Shu ChienAbstract:Vascular endothelial cells (ECs), which exist in close proximity to vascular smooth muscle cells (SMCs), are constantly subjected to blood flow–induced shear stress. Although the effect of shear stress on endothelial biology has been extensively studied, the influence of SMCs on endothelial response to shear stress remains largely unexplored. We examined the potential role of SMCs in regulating the shear stress–induced gene expression in ECs, using a parallel-plate Coculture flow system in which these 2 types of cells were separated by a porous membrane. In this Coculture system, SMCs tended to orient perpendicularly to the flow direction, whereas the ECs were elongated and aligned with the flow direction. Under static conditions, Coculture with SMCs induced EC gene expression of intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1), and E-selectin, while attenuating EC gene expression of endothelial nitric oxide synthase (eNOS). Shear stress significantly inhibited SMC-induced adhesion molecule gene expression. These EC responses under static and shear conditions were not observed in the absence of close communication between ECs and SMCs, and they were also not observed when ECs were Cocultured with fibroblasts instead of SMCs. Our findings indicate that under static conditions, Coculture with SMCs induces ICAM-1, VCAM-1, and E-selectin gene expression in ECs. These Coculture effects are inhibited by shear stress and require specific interaction between ECs and SMCs in close contact.