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Marker Nestin (marker + nestin)
Selected AbstractsTGF-,1/SMAD signaling induces astrocyte fate commitment in vitro: Implications for radial glia developmentGLIA, Issue 10 2007Joice Stipursky Abstract Radial glial (RG) cells are specialized type of cell, which functions as neuronal precursors and scaffolding guides to migrating neurons during cerebral cortex development. After neurogenesis and migration are completed, most of RG cells transform into astrocytes. Mechanism and molecules involved in this process are not completely elucidated. We previously demonstrated that neurons activate the promoter of the astrocyte maturation marker GFAP in astrocytes by secretion of transforming growth factor beta 1 (TGF-,1) in vitro. Here, we studied the role of neurons and TGF-,1 pathway in RG differentiation. To address this question, we employed cortical progenitor cultures enriched in GLAST/nestin double-labeled cells, markers of RG cells. TGF-,1 and conditioned medium derived from neuron-astrocyte cocultures (CM) decreased the number of cells expressing the precursor marker nestin and increased that expressing GFAP in cortical progenitor cultures. These events were impaired by addition of neutralizing antibodies against TGF-,1. Increase in the number of GFAP positive cells was associated with Smads 2/3 nuclear translocation, a hallmark of TGF-,1 pathway activation. PCR-assays revealed a decrease in the levels of mRNA for the RG marker, BLBP (brain lipid binding protein), due to TGF-,1 and CM treatment. We further identified TGF-,1 receptor in cortical progenitor cultures suggesting that these cells might be target for TGF-,1 during development. Our work provides strong evidence that TGF-,1 might be a novel factor involved in RG-astrocyte transformation and highlights the role of neuron-glia interaction in this process. © 2007 Wiley-Liss, Inc. [source] Rat choroid plexuses contain myeloid progenitors capable of differentiation toward macrophage or dendritic cell phenotypesGLIA, Issue 3 2006Serge Nataf Abstract The interface between the blood and the cerebrospinal fluid (CSF) is formed by the choroid plexuses (CPs), which are specialized structures located within the brain ventricles. They are composed of a vascularized stroma surrounded by a tight epithelium that controls molecular and cellular traffic between the blood and the CSF. Cells expressing myeloid markers are present within the choroidal stroma. However, the exact identity, maturation state, and functions of these CP-associated myeloid cells are not fully clarified. We show here that this cell population contains immature myeloid progenitors displaying a high proliferative potential. Thus, in neonate rats and, to a lesser extent, in adult rats, cultured CP stroma cells form large colonies of macrophages, in response to M-CSF or GM-CSF, while, under the same conditions, peripheral blood monocytes do not. In addition, under GM-CSF treatment, free-floating colonies of CD11c+ monocytic cells are generated which, when restimulated with GM-CSF and IL-4, differentiate into OX62+/MHC class II+ dendritic cells. Interestingly, in CP stroma cultures, myeloid cells are found in close association with fibroblastic-like cells expressing the neural stem-cell marker nestin. Similarly, in the developing brain, macrophages and nestin+ fibroblastic cells accumulate in vivo within the choroidal stroma. Taken together, these results suggest that the CP stroma represents a niche for myeloid progenitors and may serve as a reservoir for brain macrophages. © 2006 Wiley-Liss, Inc. [source] Specific characteristic of radial glia in the human fetal telencephalonGLIA, Issue 1 2004Nada Zecevic Abstract Phenotypic characteristics of cells in the developing human telencephalic wall were analyzed using electron microscopy and immunocytochemistry with various glial and neuronal cell markers. The results suggest that multiple defined cell types emerge in the neocortical proliferative zones and are differentially regulated during embryonic development. At 5,6 weeks gestation, three major cell types are observed. Most proliferating ventricular zone (VZ) cells are labeled with radial glial (RG) markers such as vimentin, glial fibrillary acidic protein (GFAP), and glutamate astrocyte-specific transporter (GLAST) antibodies. A subpopulation of these RG cells also express the neuronal markers , III-tubulin, MAP-2, and phosphorylated neurofilament SMI-31, in addition to the stem cell marker nestin, indicating their multipotential capacity. In addition, the presence of VZ cells that immunoreact only with neuronal markers indicates the emergence of restricted neuronal progenitors. The number of multipotential progenitors in the VZ gradually decreases, whereas the number of more restricted progenitors increases systematically during the 3-month course of human corticogenesis. These results suggest that multipotential progenitors coexist with restricted neuronal progenitors and RG cells during initial corticogenesis in the human telencephalon. Since the multipotential VZ cells disappear during the major wave of neocortical neurogenesis, the RG and restricted neuronal progenitors appear to serve as the main sources of cortical neurons. Thus, the diversification of cells in human VZ and overlying subventricular zone (SVZ) begins earlier and is more pronounced than in rodents. © 2004 Wiley-Liss, Inc. [source] Longterm quiescent cells in the aged human subventricular neurogenic system specifically express GFAP-,AGING CELL, Issue 3 2010Simone A. Van Den Berge Summary A main neurogenic niche in the adult human brain is the subventricular zone (SVZ). Recent data suggest that the progenitors that are born in the human SVZ migrate via the rostral migratory stream (RMS) towards the olfactory bulb (OB), similar to what has been observed in other mammals. A subpopulation of astrocytes in the SVZ specifically expresses an assembly-compromised isoform of the intermediate filament protein glial fibrillary acidic protein (GFAP-,). To further define the phenotype of these GFAP-, expressing cells and to determine whether these cells are present throughout the human subventricular neurogenic system, we analysed SVZ, RMS and OB sections of 14 aged brain donors (ages 74-93). GFAP-, was expressed in the SVZ along the ventricle, in the RMS and in the OB. The GFAP-, cells in the SVZ co-expressed the neural stem cell (NSC) marker nestin and the cell proliferation markers proliferating cell nuclear antigen (PCNA) and Mcm2. Furthermore, BrdU retention was found in GFAP-, positive cells in the SVZ. In the RMS, GFAP-, was expressed in the glial net surrounding the neuroblasts. In the OB, GFAP-, positive cells co-expressed PCNA. We also showed that GFAP-, cells are present in neurosphere cultures that were derived from SVZ precursors, isolated postmortem from four brain donors (ages 63-91). Taken together, our findings show that GFAP-, is expressed in an astrocytic subpopulation in the SVZ, the RMS and the OB. Importantly, we provide the first evidence that GFAP-, is specifically expressed in longterm quiescent cells in the human SVZ, which are reminiscent of NSCs. [source] Analysis of neural potential of human umbilical cord blood,derived multipotent mesenchymal stem cells in response to a range of neurogenic stimuliJOURNAL OF NEUROSCIENCE RESEARCH, Issue 9 2008Isabel Zwart Abstract We investigated the neurogenic potential of full-term human umbilical cord blood (hUCB),derived multipotent mesenchymal stem cells (MSCs) in response to neural induction media or coculture with rat neural cells. Phenotypic and functional changes were assessed by immunocytochemistry, RT-PCR, and whole-cell patch-clamp recordings. Naive MSCs expressed both mesodermal and ectodermal markers prior to neural induction. Exposure to retinoic acid, basic fibroblast growth factor, or cyclic adenosine monophosphate (cAMP) did not stimulate neural morphology, whereas exposure to dibutyryl cAMP and 3-isobutyl-1-methylxanthine stimulated a neuron-like morphology but also appeared to be cytotoxic. All protocols stimulated increases in expression of the neural precursor marker nestin, but expression of mature neuronal or glial markers MAP2 and GFAP was not observed. Nestin expression increases were serum level dependent. Electrophysiological properties of MSCs were studied with whole-cell patch-clamp recordings. The MSCs possessed no ionic currents typical of neurons before or after neural induction protocols. Coculture of hUCB-derived MSCs and rat neural cells induced some MSCs to adopt an astrocyte-like morphology and express GFAP protein and mRNA. Our data suggest hUCB-derived MSCs do not transdifferentiate into mature functioning neurons in response to the above neurogenic protocols; however, coculture with rat neural cells led to a minority adopting an astrocyte-like phenotype. © 2008 Wiley-Liss, Inc. [source] Nestin is expressed in HMB-45 negative melanoma cells in dermal parts of nodular melanomaTHE JOURNAL OF DERMATOLOGY, Issue 6 2010Maho KANOH Abstract Nestin, a marker of neural stem cells, is expressed in the stem cells of the mouse hair follicle. The nestin-expressing hair follicle stem cells can differentiate into neurons, glia, keratocytes, smooth muscle cells and melanocytes in vitro. These pluripotent nestin-expressing stem cells are keratin 15 (K15)-negative, suggesting that they are in a relatively undifferentiated state. Recent studies suggest that the epithelial stem cells are important in tumorigenesis, and nestin expression is thought to be important in tumorigenesis. In the present study, we examined the expression of the hair follicle and neural stem cell marker nestin, as well as S-100 and HMB-45, in melanoma. Nestin immunoreactivity was observed in the HMB-45-negative melanoma cells in all five cases of amelanotic nodular melanomas. Moreover, nestin immunoreactivity was observed in the dermal parts in seven of 10 cases of melanotic nodular melanomas. Especially, nestin immunoreactivity was observed in the HMB-45-negative melanoma cells in the dermal parts of all 10 cases of HMB-45-negative amelanotic and melanotic nodular melanomas. On the other hand, nestin expression was negative in 10 of 12 cases of superficial spreading melanoma. These results suggest that nestin is an important marker of HMB-45-negative melanoma cells in the dermal parts of patients with nodular melanoma. [source] Expression of the stem cell marker nestin in peripheral blood of patients with melanomaBRITISH JOURNAL OF DERMATOLOGY, Issue 1 2010A. Fusi Summary Background, There is continued interest in markers indicative of circulating melanoma cells. Nestin is a neuroepithelial intermediate filament protein that was found to be expressed in melanoma and in various cancer stem cells. Objectives, We investigated expression of nestin in peripheral blood of patients with melanoma. Methods, We analysed nestin expression by flow cytometry and by quantitative reverse transcription,polymerase chain reaction both in tissues (n = 23) and in blood samples (n = 102) from patients with American Joint Committee on Cancer stage III,IV melanoma. Forty-six negative controls were also added. Results, Flow cytometry did not reveal nestin-expressing cells in peripheral blood of healthy volunteers. In patients with melanoma, however, nestin protein was expressed in a proportion of melanoma cells enriched from peripheral blood by immunomagnetic sorting. In melanoma tissue samples a significant correlation was found between mRNAs coding for nestin and tyrosinase (P = 0·001) and melan-A (P = 0·002), whereas in blood a significant correlation was observed only for tyrosinase (P = 0·015), but not for melan-A (P = 0·53). Nestin expression was higher in stage IV patients compared with stage III/IV with no evidence of disease, in patients with high tumour burden, and was positively correlated to expression of tyrosinase and melan-A. Conclusions, Nestin was found to be an additional marker of interest for circulating melanoma cells. Prospective studies should investigate its potential added informative value in comparison with markers already in use for melanoma cell detection. [source] | |||||||||||||