Articles: phenotype.
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The Asp22fs(g.63_64insC) mutation in progranulin gene (GRN) has been so far reported in one patient who developed frontotemporal dementia (FTD) at the age of 65. Here, we describe the clinical heterogeneity associated with the GRN Asp22fs mutation in a large Italian family. Clinical and instrumental workup of two symptomatic carriers in two generations has been carried out, together with genetic analysis of probands and of nine asymptomatic family members. ⋯ Cerebrospinal fluid amyloid-β, tau, and phosphotau protein levels were in both cases in the range of normality. Additional nine asymptomatic family members were studied. This family's description expands the spectrum of clinical presentations of frontotemporal lobar degeneration caused by GRN mutations, suggesting that the diagnosis could be missed in some individuals with an atypical presentation, and points up the importance of GRN plasma level evaluation.
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Biologie aujourd'hui · Jan 2011
Review[Phenotypic plasticity of neural crest-derived melanocytes and Schwann cells].
Melanocytes, the pigmented cells of the skin, and the glial Schwann cells lining peripheral nerves are developmentally derived from an early and transient ectodermal structure of the vertebrate embryo, the neural crest, which is also at the origin of multiple neural and non-neural cell types. Besides melanocytes and neural cells of the peripheral nervous system, the neural crest cells give rise to mesenchymal cell types in the head, which form most of the craniofacial skeleton, dermis, fat tissue and vascular musculo-connective components. How such a wide diversity of differentiation fates is established during embryogenesis and is later maintained in adult tissues are among key questions in developmental and stem cell biology. ⋯ When challenged with new environmental conditions in vitro, differentiated Schwann cells and pigment cells can reacquire stem cell properties of their neural crest ancestors. Notably, such reprogramming was achieved through the effect of a single exogenous factor and without the need of any induced genetic modification. Deciphering the cellular and molecular mechanisms that regulate the plasticity and maintenance of neural crest-derived differentiated cells is likely to be an important step towards the understanding of the neurocristopathies and cancers that target neural crest derivatives in humans.
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Natural killer T cells represent a linkage between innate and adaptive immunity. They are a heterogeneous population of specialized T lymphocytes composed of different subsets. DX5+NKT cells are characterized by expression of the NK cell marker DX5 in the context of CD3. However, little is known about the phenotype and functional capacity of this unique cell population. Therefore, we investigated the expression of several T cell and NK cell markers, as well as functional parameters in spleen and liver subsets of DX5+NKT cells in NK1.1- Balb/c mice and compared our findings to NK1.1+ C57Bl/6 mice. ⋯ These results show that DX5+NKT cells are a heterogeneous population, depending on the dedicated organ and mouse strain, that has diverse functional capacity.
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Arthritis and rheumatism · Dec 2010
Characterization of the human nucleus pulposus cell phenotype and evaluation of novel marker gene expression to define adult stem cell differentiation.
Development of stem cell therapies for regenerating the nucleus pulposus (NP) are hindered by the lack of specific markers by which to distinguish NP cells from articular chondrocytes (ACs). The purpose of this study was to define the phenotype profile of human NP cells using gene expression profiling and to assess whether the identified markers could distinguish mesenchymal stem cell (MSC) differentiation to a correct NP cell phenotype. ⋯ This study is the first to use gene expression profiling to identify the human NP cell phenotype. Importantly, these markers can be used to determine the in vitro differentiation of MSCs to an NP-like, rather than an AC-like, phenotype. Interestingly, these results suggest that AD-MSCs may be a more appropriate cell type than BM-MSCs for use in engineering intervertebral disc tissue.
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Arthritis and rheumatism · Dec 2010
Phenotypic alterations of neurons that innervate osteoarthritic joints in rats.
Pain is a prominent feature of osteoarthritis (OA). To further understand the primary mechanisms of nociception in OA, we studied the expression of the phenotype markers calcitonin gene-related peptide (CGRP), isolectin B4 (IB4), and neurofilament 200 (NF200) in sensory neurons innervating the OA knee joint in rats. ⋯ These results indicate that MIA-induced OA causes an up-regulation of CGRP in different subpopulations of primary afferent neurons in DRG due to a phenotypic switch and/or cell hypertrophy which may be functionally relevant in terms of the onset of pain in this pathologic condition.