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Neurosphere
About: Neurosphere is a research topic. Over the lifetime, 5145 publications have been published within this topic receiving 321088 citations.
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TL;DR: How the concept of the matrix cell (multipotent neural stem cells in vivo) emerged and what has come out from this view over the last 45 years is described, and how the basic concept ofThe matrix cell theory has recently been reconfirmed after a long period of controversy and neglect.
Abstract: In the early 1960s I applied 3H-thymidine autoradiography to the study of the cells constituting the neural tube, and found that its wall was composed solely of one kind of single-layered epithelial cell, which perform an elevator movement between the mitotic and DNA-synthetic zones in the wall in accord with the cell cycle. They were identified as multipotent stem cells of the central nervous sytem (CNS) to which I gave the name of matrix cells. (3)H-thymidine autoradiography also revealed the chronology of development of these matrix cells: At first they proliferate only to expand the population (stage I), then switch to differentiate specific neuroblasts in given sequences (stage II), and finally change themselves into ependymoglioblasts, common progenitors of ependymal cells and neuroglia (stage III). Based on these findings, I proposed a monophyletic view of cytogenesis of the central nervous sytem. This matrix cell theory claiming the existence of multipotent stem cells has long been the target of severe criticism and not been accepted among neuro-embryologists for a long time. Recent findings by experimental and clinical neuroscientists on the importance of stem cells have renewed interest in the nature and biology of the multipotent neural stem cells. The present paper describes how the concept of the matrix cell (multipotent neural stem cells in vivo) emerged and what has come out from this view over the last 45 years, and how the basic concept of the matrix cell theory has recently been reconfirmed after a long period of controversy and neglect.
78 citations
TL;DR: Measles virus derivatives have significant antitumor activity against glioma-derived stem cells in vitro and in vivo, and abundant syncytia and viral replication was demonstrated in tumors of MV-treated mice.
Abstract: Glioblastoma (GBM) is the most common primary brain tumor in adults and has a dismal prognosis despite multimodality treatment. Given the resistance of glioma stem cells (GSC) to chemotherapy and radiation therapy, their eradication could prevent tumor recurrence. We sought to evaluate the antitumor activity of measles virus (MV) derivatives against GSC. We generated neurosphere cultures from patient-derived primary tumor GBM xenografts, and we characterized them for the GSC markers CD133, SOX2, Nestin, ATF5 and OLIG2. Using the MV-strains MV-GFP, MV-CEA and MV-NIS we demonstrated infection, viral replication and significant cytopathic effect in vitro against GSC lines. In tumorigenicity experiments, GBM44 GSC were infected with MV in vitro and subsequently implanted into the right caudate nucleus of nude mice: significant prolongation of survival in mice implanted with infected GSC was observed, compared with mock-infected controls (P=0.0483). In therapy experiments in GBM6 and GBM12 GSC xenograft models, there was significant prolongation of survival in MV-GFP-treated animals compared with inactivated virus-treated controls (GBM6 P=0.0021, GBM12 P=0.0416). Abundant syncytia and viral replication was demonstrated in tumors of MV-treated mice. Measles virus derivatives have significant antitumor activity against glioma-derived stem cells in vitro and in vivo.
78 citations
TL;DR: The results suggest that the IPE derived cells have retinal stem/progenitor properties and neurogenic potential without gene transfer, thereby providing a novel potential source for both basic stem cell biology and therapeutic applications for retinal diseases.
78 citations
TL;DR: It is demonstrated that NSC microenvironments modulate cellular activity throughout the neurosphere, contributing to the understanding of ECM-mediated NSC behavior and provide new avenues for developing rationally designed couriers for neurotransplantation.
Abstract: Biomaterial matrices presenting extracellular matrix (ECM) components in a controlled three-dimensional configuration provide a unique system to study neural stem cell (NSC)-ECM interactions. We cultured primary murine neurospheres in a methylcellulose (MC) scaffold functionalized with laminin-1 (MC-x-LN1) and monitored NSC survival, apoptosis, migration, differentiation, and matrix production. Overall, MC-x-LN1 enhanced both NSC survival and maturation compared with MC controls. Significantly lower levels of apoptotic activity were observed in MC-x-LN1 than in MC controls, as measured by bcl-2/bax gene expression and tetramethylrhodamine-dUTP nick end labeling. A higher percentage of NSCs extended neurites in a β₁-integrin-mediated fashion in MC-x-LN1 than in MC controls. Further, the differentiation profiles of NSCs in MC-x-LN1 exhibited higher levels of neuronal and oligodendrocyte precursor markers than in MC controls. LN1 production and co-localization with α₆β₁ integrins was markedly increased within MC-x-LN1, whereas the production of fibronectin was more pronounced in MC controls. These findings demonstrate that NSC microenvironments modulate cellular activity throughout the neurosphere, contributing to our understanding of ECM-mediated NSC behavior and provide new avenues for developing rationally designed couriers for neurotransplantation.
78 citations
TL;DR: It is demonstrated that induced overexpression of transcription factor genes has profound and specific effects on the differentiation of rat and human midbrain progenitors, although few dopamine neurons are generated.
Abstract: Neurons derived from neural stem cells could potentially be used for cell therapy in neurodegenerative disorders, such as Parkinson's disease. To achieve controlled differentiation of neural stem cells, we expressed transcription factors involved in the development of midbrain dopaminergic neurons in rat and human neural progenitors. Using retroviral-mediated transgene delivery, we overexpressed Lmx1a (LIM homeobox transcription factor 1, alpha), Msx1 (msh homeobox homolog 1), Ngn2 (neurogenin 2), or Pitx3 (paired-like homeodomain transcription factor 3) in neurospheres derived from embryonic day 14.5 rat ventral mesencephalic progenitors. We also expressed either Lmx1a or Msx1 in the human embryonic midbrain-derived progenitor cell line NGC-407. Rat cells transduced with Ngn2 exited the cell cycle and expressed the neuronal marker microtubule-associated protein 2 and catecholamine-neuron protein vesicular monoamine transporter 2. Interestingly, Pitx3 downregulated the expression of SOX2 (SRY-box containing gene 2) and Nestin, altered cell morphology, but never induced neuronal or glial differentiation. Ngn2 exhibited a strong neuron-inducing effect. In contrast, few Lmx1a-transduced cells matured into neurons, and Msx1 overexpression promoted oligodendrogenesis rather than neuronal differentiation. Importantly, none of these four genes, alone or in combination, enhanced differentiation of rat neural stem cells into dopaminergic neurons. Notably, the overexpression of Lmx1a, but not Msx1, in human neural progenitors increased the yield of tyrosine hydroxylase-immunoreactive cells by threefold. Together, we demonstrate that induced overexpression of transcription factor genes has profound and specific effects on the differentiation of rat and human midbrain progenitors, although few dopamine neurons are generated.
78 citations