scholarly journals Brain Tumour Stem Cells and Neural Stem Cells: Still Explored by the Same Approach?

2008 ◽  
Vol 36 (5) ◽  
pp. 890-895 ◽  
Author(s):  
W Liu ◽  
G Shen ◽  
Z Shi ◽  
F Shen ◽  
X Zheng ◽  
...  

Brain tumour stem cells (BTSCs) are chiefly responsible for the in vivo long-term growth and recurrence of malignant gliomas and may be a potential treatment target. They resemble neural stem cells (NSCs), so their self-renewal and differentiation are currently investigated by the same methods used to study NSCs. There are, however, essential differences between these cell types: in many cases the marker expression pattern of BTSCs does not match the CD133+/NSE−/FAP− pattern of NSCs; BTSC tumourigenicity is independent of marker expression; and while attachment, serum-containing medium and withdrawal of mitogens (epidermal growth factor [EGF] and basic fibroblast growth factor [bFGF]) are essential to induce NSCs to differentiate, they do not affect BTSC tumourigenicity. Evidence implies that research on the renewal and differentiation of BTSCs should be orientated towards tumourigenicity and is essentially a pharmaceutical problem. Such an approach may contribute to the development of an accurate definition of BTSCs and to the search for selective differentiation-inducing drugs for BTSCs.

Development ◽  
1995 ◽  
Vol 121 (7) ◽  
pp. 2069-2077
Author(s):  
E.D. Newman-Smith ◽  
Z. Werb

Mouse embryos containing only maternal chromosomes (parthenotes) develop abnormally in vivo, usually failing at the peri-implantation stage. We have analyzed the development of parthenote embryos by using an inner cell mass (ICM) outgrowth assay that mimics peri-implantation development. ICMs from normal embryos maintained undifferentiated stem cells positive for stage-specific embryonic antigen-1 and Rex-1 while differentiating into a variety of cell types, including visceral endoderm-like cells and parietal endoderm cells. In contrast, ICMs from parthenotes failed to maintain undifferentiated stem cells and differentiated almost exclusively into parietal endoderm. This suggests that parthenote ICMs have a defect that leads to differentiation, rather than maintenance, of the stem cells, and a defect that leads to a parietal endoderm fate for the stem cells. To test the hypothesis that the ICM population is not maintained owing to a lack of proliferation of the stem cells, we investigated whether mitogenic agents were able to maintain the ICM population in parthenotes. When parthenote blastocysts were supplied with the insulin-like growth factor-1 receptor (Igf-1r) and insulin-like growth factor-2 (Igf-2), two genes not detectable in parthenote blastocysts by in situ hybridization, the ICM population was maintained. Similarly, culture of parthenote blastocysts in medium conditioned by embryonic fibroblasts and supplemented with the maternal factor leukemia inhibitory factor maintained the ICM population. However, once this growth factor-rich medium was removed, the parthenote ICM cells still differentiated predominantly into parietal endoderm.(ABSTRACT TRUNCATED AT 250 WORDS)


2006 ◽  
Vol 14 (3) ◽  
pp. 237-248 ◽  
Author(s):  
Anne Schänzer ◽  
Frank-Peter Wachs ◽  
Daniel Wilhelm ◽  
Till Acker ◽  
Christiana Cooper-Kuhn ◽  
...  

e-Neuroforum ◽  
2013 ◽  
Vol 19 (2) ◽  
Author(s):  
Marisa Karow ◽  
Benedikt Berninger

AbstractThe art of forging neurons: direct reprogramming of somatic cells into induced neu­ronal cells.Cellular reprogramming has shed new light on the plasticity of terminally differentiated cells and discloses novel strategies for cell-based therapies for neurological disorders. With accumulating knowledge of the programs underlying the genesis of the distinct neural cell types, especially with the identification of relevant transcription factors and microRNAs, reprogramming of somatic cells of different origins into induced neuronal cells or neural stem cells has been successfully achieved. Starting with the general con­cept of reprogramming we discuss here three different paradigms: 1) direct conversion of CNS-foreign cells such as skin fibroblasts into induced neuronal cells or neural stem cells; 2) transdifferentiation of CNS resident cells such as astrocytes and brain pericytes into induced neuronal cells; 3) reprogramming of one neuronal subtype into another. The latter has already been successfully achieved in vivo during early brain develop­ment, providing strong impulse for the attempt to succeed in direct reprogramming in situ for future brain repair.


e-Neuroforum ◽  
2013 ◽  
Vol 19 (2) ◽  
Author(s):  
M. Karow ◽  
B. Berninger

AbstractCellular reprogramming has shed new light on the plasticity of terminally differentiated cells and unearthed novel strategies for cell-based therapies to treat neurological disor­ders. With accumulating knowledge of the programs underlying the genesis of the dis­tinct neural cell types, particularly the iden­tification of crucial transcription factors and microRNAs, reprogramming of somatic cells of different origins into induced neuronal cells or neural stem cells has been success­fully achieved. Starting with the general con­cept of reprogramming, we discuss three dif­ferent paradigms: (1) direct conversion of central nervous system (CNS) foreign cells such as skin fibroblasts into induced neuro­nal cells or neural stem cells; (2) transdiffer­entiation of CNS resident cells such as astro­cytes and brain pericytes into induced neuro­nal cells; (3) reprogramming of one neuronal subtype into another. The latter has already been successfully achieved in vivo during ear­ly brain development, providing a strong im­pulse to attempt direct reprogramming in si­tu for future brain repair.


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1674-1674
Author(s):  
Sheng Zhou ◽  
Soghra Fatima ◽  
Brian P. Sorrentino

Abstract Neural stem cells have been identified in both the cerebellum and forebrain of fetal and adult mice. These cells can form neurospheres in culture and differentiate into both glia and neurons either in vitro or in vivo. In embryonic day 14 forebrain, neural stem cells are found to exist exclusively in a subpopulation with the Side Population (SP) phenotype, and express Abcg2, a member of the ABC transporter family that is responsible for the SP phenotype in hematopoietic stem cells (HSCs). The expression of Abcg2 in stem cells in the cerebellum has not been characterized. We have generated an Abcg2/GFP knock-in mouse model in which expression of GFP is under control of the endogenous Abcg2 locus and used this model to demonstrate that Abcg2 expression can be used for HSC enrichment. Here we report the use of this mouse model to explore the relationship between Abcg2 expression and neural stem cell function in neonatal cerebellum. Single cells were prepared from cerebellum of 4–9 day old mice by digesting with papain. We then stained the cells with anti-CD45 and anti-Ter119 antibody to exclude the resident hematopoietic cells in subsequent flow cytometry analysis and cell sorting. We found that a small but consistent subpopulation of cells, comprising 0.7±0.12% of total CD45−Ter119- single cell preparations, expressed the Abcg2/GFP allele. To determine whether these GFP+ cells were enriched for neural stem cells, we sorted the CD45−Ter119- cells into GFP+ and GFP− subpopulations and analyzed for their neurosphere forming activity in the presence of epidermal growth factor and basic fibroblast growth factor. We found that the GFP+ subpopulation formed 21 fold more neurospheres compared with the GFP− subpopulation. These neurosphere forming cells can self-renew as evidenced by their capacity to form secondary neurospheres when replated. These results demonstrate that similar to what is seen with HSCs and with embryonic forebrain cells, Abcg2 is expressed in the neural stem cells in neonatal cerebellum, and Abcg2/GFP expression in this mouse model could also be used as a marker to prospectively purify neural stem cells from cerebellum. Ongoing studies are focused on defining the in vivo multilineage differentiation potential of the Abcg2/GFP+ cells and determining whether Abcg2 expression could be used as a marker for purification of medulloblastoma stem cells.


2012 ◽  
Vol 214 (2) ◽  
pp. 113-119 ◽  
Author(s):  
Peter J Hornsby

Adrenarche is a cell biological and endocrinological puzzle. The differentiation of the zona reticularis in childhood in humans requires special techniques for study because it is confined to humans and possibly a small number of other primates. Despite the rapid progress in the definition of adrenocortical stem/progenitor cells in the mouse, the factors that cause the differentiation of adrenocortical cells into zonal cell types have not been identified. There are, however, many candidates in the Wnt, Hedgehog, and other families of signaling molecules. A suitable system for identifying authentic stem cells, capable of differentiation into all zones, has yet to be developed. It is proposed here that the in vitro differentiation of pluripotent cells, combined with appropriate in vitro and in vivo methods for validating authentic adrenocortical stem cells, is a promising approach to solving these questions.


2019 ◽  
Author(s):  
Merve Deniz Abdusselamoglu ◽  
Lisa Landskron ◽  
Sarah K. Bowman ◽  
Elif Eroglu ◽  
Thomas Burkard ◽  
...  

AbstractDuring central nervous system (CNS) development, spatiotemporal gene expression programs mediate specific lineage decisions to generate neuronal and glial cell types from neural stem cells (NSCs). However, little is known about the epigenetic landscape underlying these highly complex developmental events. Here, we perform ChIP-seq on distinct subtypes of Drosophila FACS-purified neural stem cells (NSCs) and their differentiated progeny to dissect the epigenetic changes accompanying the major lineage decisions in vivo. By analyzing active and repressive histone modifications, we show that stem cell identity genes are silenced during differentiation by loss of their activating marks and not via repressive histone modifications. Our analysis also uncovers a new set of genes specifically required for altering lineage patterns in type II neuroblasts, one of the two main Drosophila NSC identities. Finally, we demonstrate that this subtype specification in NBs, unlike NSC differentiation, requires Polycomb-group (PcG)-mediated repression.Summary statementDynamic epigenetic landscape of Drosophila neural stem cell lineages.


Author(s):  
Prithiv K R Kumar

Renal failure is a major health problem. The mortality rate remain high despite of several therapies. The most complex of the renal issues are solved through stem cells. In this review, different mechanism for cure of chronic kidney injury along with cell engraftment incorporated into renal structures will be analysed. Paracrine activities of embryonic or induced Pluripotent stem cells are explored on the basis of stem cell-induced kidney regeneration. Several experiments have been conducted to advance stem cells to ensure the restoration of renal functions. More vigour and organised protocols for delivering stem cells is a possibility for advancement in treatment of renal disease. Also there is a need for pressing therapies to replicate the tissue remodelling and cellular repair processes suitable for renal organs. Stem cells are the undifferentiated cells that have the ability to multiply into several cell types. In vivo experiments on animal’s stem cells have shown significant improvements in the renal regeneration and functions of organs. Nevertheless more studies show several improvements in the kidney repair due to stem cell regeneration.


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