Search results for "Cellular differentiation"
showing 10 items of 482 documents
Constant detection of cyclooxygenase 2 in terminal stages of myeloid maturation.
2006
Detection of a TLR2 agonist by hematopoietic stem and progenitor cells impacts the function of the macrophages they produce
2013
Several groups have shown that detection of microbial components by TLRs on hematopoietic stem and progenitor cells (HSPCs) instructs myeloid cell generation, raising interest in the possibility of targeting TLRs on HSPCs to boost myelopoiesis. However, although "TLR-derived" cells exhibit myeloid cell characteristics (phagocytosis, cytokine production, antigen presentation), it is not clear whether they are functionally equivalent to macrophages derived in the absence of TLR activation. Our in vitro and in vivo studies show that macrophages derived from mouse and human HSPC subsets (including stem cells) exposed to a TLR2 agonist prior to or during macrophage differentiation produce lower …
G.P.199
2014
Our group has recently derived skeletal muscle from dermis-derived cells, by using an extracellular matrix that recreates the myogenic niche. After one week of differentiation, we observed isolated, twitching myotubes followed by spontaneous contractions of the entire tissue-engineered muscle construct. In vitro engineered myofibers expressed canonical markers, ultrastructure and electrophysiological characteristics of skeletal muscle. Interestingly, after one-month engineered muscle constructs showed progressive degradation of the myofibers concomitant with fatty infiltration, paralleling the natural course of muscular degeneration. However, we do not yet know how dermis-resident precursor…
Investigating the Role of Guanosine on Human Neuroblastoma Cell Differentiation and the Underlying Molecular Mechanisms
2021
Neuroblastoma arises from neural crest cell precursors failing to complete the process of differentiation. Thus, agents helping tumor cells to differentiate into normal cells can represent a valid therapeutic strategy. Here, we evaluated whether guanosine (GUO), a natural purine nucleoside, which is able to induce differentiation of many cell types, may cause the differentiation of human neuroblastoma SH-SY5Y cells and the molecular mechanisms involved. We found that GUO, added to the cell culture medium, promoted neuron-like cell differentiation in a time- and concentration-dependent manner. This effect was mainly due to an extracellular GUO action since nucleoside transporter inhibitors r…
miR379-410 cluster miRNAs regulate neurogenesis and neuronal migration by fine-tuning N-cadherin
2014
N-cadherin-mediated adhesion is essential for maintaining the tissue architecture and stem cell niche in the developing neocortex. N-cadherin expression level is precisely and dynamically controlled throughout development; however, the underlying regulatory mechanisms remain largely unknown. MicroRNAs (miRNAs) play an important role in the regulation of protein expression and subcellular localisation. In this study, we show that three miRNAs belonging to the miR379–410 cluster regulate N-cadherin expression levels in neural stem cells and migrating neurons. The overexpression of these three miRNAs in radial glial cells repressed N-cadherin expression and increased neural stem cell different…
Homeostasis of Microglia in the Adult Brain: Review of Novel Microglia Depletion Systems.
2015
Microglia are brain macrophages that emerge from early erythro-myeloid precursors in the embryonic yolk sac and migrate to the brain mesenchyme before the blood brain barrier is formed. They seed the brain, and proliferate until they have formed a grid-like distribution in the central nervous system that is maintained throughout lifespan. The mechanisms through which these embryonic-derived cells contribute to microglia homoeostasis at steady state and upon inflammation are still not entirely clear. Here we review recent studies that provided insight into the contribution of embryonically-derived microglia and of adult 'microglia-like' cells derived from monocytes during inflammation. We ex…
Triiodothyronine-Induced Shortening of Chromatin Repeat Length in Neurons Cultured in a Chemically Denned Medium
1987
Abstract: At the time of terminal differentiation, mammalian cortical neurons undergo a dramatic change in the structural organization of their chromatin: the nucleosomal repeat length shortens from ∼200 base pairs in fetuses to a value of 165 base pairs after birth. These events occur several days after the end of neuronal proliferation. Previously, we reported that rat cortical neurons cultured in a very selective synthetic medium were not yet programmed to these events at the end of mitotic cycles. Herein, we report that addition of triiodothyronine to neuronal cultures induces a shortening of the chromatin repeat length comparable to the natural one. Copyright © 1987, Wiley Blackwell. A…
Sequential Hepatogenic Transdifferentiation of Adipose Tissue-Derived Stem Cells: Relevance of Different Extracellular Signaling Molecules, Transcrip…
2009
Adipose tissue contains a mesenchymal stein cell (MSC) population Known as adipose-derived stein cells (ASCs) capable of differentiating into different cell types. Our aim was to induce hepatic transdifferentiation of ASCs by sequential exposure to several combinations of cytokines, growth factors, and hormones. The most efficient hepatogenic protocol includes fibroblastic growth factors (FGF) 2 and 4 and epidermal growth factor (EGF) (step 1), hepatocyte growth factor (HGF), FGF2, FGF4, and nicotinamide (Nic) (step 2), and oncostatin M (OSM), dexamethasone (Dex), and insulin-tranferrin-selenium (step 3). This protocol activated transcription factors [GATA6, Hex, CCAAT/enhancer binding prot…
Neurotoxic effects of ochratoxin A on the subventricular zone of adult mouse brain
2014
Ochratoxin A (OTA), a mycotoxin that was discovered as a secondary metabolite of the fungal species Aspergillus and Penicillium, is a common contaminant in food and animal feed. This mycotoxin has been described as teratogenic, carcinogenic, genotoxic, immunotoxic and has been proven a potent neurotoxin. Other authors have previously reported the effects of OTA in different structures of the central nervous system as well as in some neurogenic regions. However, the impact of OTA exposure in the subventricular zone (SVZ) has not been assessed yet. To elucidate whether OTA affects neural precursors of the mouse SVZ we investigated, in vitro and in vivo, the effects of OTA exposure on the SVZ …
Staging of Bladder Cancer
1982
It is well established that the prognosis of cancer patients depends on several factors including: the local extension of the tumour, and the presence of single or multiple tumours; the presence or absence of lymph-node metastases and/or distant metastases; the presence or absence of neoplastic cells in lymphatics or in blood vessels; the histopathological type and architecture; the degree of cellular differentiation; the tumour — host relationship, including the patient’s immunological reactivity.