Premature ovarian insufficiency (POI) is defined as the loss of ovarian activity under the age of 40. Theca cells (TCs) play a vital role during folliculogenesis and TCs dysfunction participate in the pathogenesis of POI. Therefore, transplantation of thecal stem cells (TSCs), which are capable of self-renewal and differentiation into mature TCs, may provide a new strategy for treating POI.
View Article and Find Full Text PDFSomatic cells can be successfully reprogrammed into pluripotent stem cells by the ectopic expression of defined transcriptional factors. However, improved efficiency and better understanding the molecular mechanism underlying reprogramming are still required. In the present study, a scrape loading/dye transfer assay showed that human induced pluripotent stem cells (hiPSCs) contained functional gap junctions partially contributed by Connexin 45 (CX45).
View Article and Find Full Text PDFCorneal endothelial cells (CECs) are a monolayer of cells covering the inner-side of cornea, playing a pivotal role in keeping the cornea transparent. Because adult CECs have no proliferative capacity, the loss of CECs during aging or under pathological conditions would lead to corneal edema, eventually leading to the blindness. Clinically, donated CECs have been successfully transplanted to treat the diseases of CEC deficiency; however, the source of CEC donation is very limited.
View Article and Find Full Text PDFGene editing in non-human primates may lead to valuable models for exploring the etiologies and therapeutic strategies of genetically based neurological disorders in humans. However, a monkey model of neurological disorders that closely mimics pathological and behavioral deficits in humans has not yet been successfully generated. Microcephalin 1 (MCPH1) is implicated in the evolution of the human brain, and MCPH1 mutation causes microcephaly accompanied by mental retardation.
View Article and Find Full Text PDFBoth diffusible factors acting in trans and chromatin components acting in cis are implicated in gene regulation, but the extent to which either process causally determines a cell's transcriptional identity is unclear. We recently used cell fusion to define a class of silent genes termed "cis-silenced" (or "occluded") genes, which remain silent even in the presence of trans-acting transcriptional activators. We further showed that occlusion of lineage-inappropriate genes plays a critical role in maintaining the transcriptional identities of somatic cells.
View Article and Find Full Text PDFIt is a long-held paradigm that cell fusion reprograms gene expression but the extent of reprogramming and whether it is affected by the cell types employed remain unknown. We recently showed that the silencing of somatic genes is attributable to either trans-acting cellular environment or cis-acting chromatin context. Here, we examine how trans- versus cis-silenced genes in a somatic cell type behave in fusions to another somatic cell type or to embryonic stem cells (ESCs).
View Article and Find Full Text PDFThe progressive restriction of cell fate during lineage differentiation is a poorly understood phenomenon despite its ubiquity in multicellular organisms. We recently used a cell fusion assay to define a mode of epigenetic silencing that we termed "occlusion", wherein affected genes are silenced by cis-acting chromatin mechanisms irrespective of whether trans-acting transcriptional activators are present. We hypothesized that occlusion of lineage-inappropriate genes could contribute to cell fate restriction.
View Article and Find Full Text PDFThe intermediate filament protein, nestin, is a widely employed marker of multipotent neural stem cells (NSCs). Recent in vitro studies have implicated nestin in a number of cellular processes, but there is no data yet on its in vivo function. Here, we report the construction and functional characterization of Nestin knockout mice.
View Article and Find Full Text PDFTechniques for small molecule screening are widely used in biological mechanism study and drug discovery. Here, we reported a novel adipocyte differentiation assay for small molecule selection, based on human mesenchymal stem cells (hMSCs) transduced with fluorescence reporter gene driven by adipogenic specific promoter--adipocyte Protein 2 (aP2; also namely Fatty Acid Binding Protein 4, FABP4). During normal adipogenic induction as well as adipogenic inhibition by Ly294002, we confirmed that the intensity of green fluorescence protein corresponded well to the expression level of aP2 gene.
View Article and Find Full Text PDFBackground: Embryonic stem (ES) cells have attracted significant attention from researchers around the world because of their ability to undergo indefinite self-renewal and produce derivatives from the three cell lineages, which has enormous value in research and clinical applications. Until now, many ES cell lines of different mammals have been established and studied. In addition, recently, AS-ES1 cells derived from Apodemus sylvaticus were established and identified by our laboratory as a new mammalian ES cell line.
View Article and Find Full Text PDFInduced pluripotent stem cells are derived from somatic cells by forced expression of several transcriptional factors. Induced pluripotent stem cells resemble embryonic stem cells in many aspects, such as the expression of certain stem cell markers, chromatin methylation patterns, embryoid body formation and teratoma formation. Therefore, induced pluripotent stem cells provide a powerful tool for study of developmental biology and unlimited resources for transplantation therapy.
View Article and Find Full Text PDFBiochem Biophys Res Commun
May 2009
The RC2 antibody is widely used to label mouse radial glial cells in the developing central nervous system. While the antibody is known to recognize a 295-kDa intermediate filament proximal protein, the gene encoding the RC2 antigen remains to be identified. Here, we present evidences clearly demonstrating that Nestin encodes the RC2 antigen.
View Article and Find Full Text PDFMesenchymal stem cells (MSCs) have received considerable attention in recent years. Particularly exciting is the prospect that MSCs could be differentiated into specialized cells of interest, which could then be used for cell therapy and tissue engineering. MSCs derived from nonhuman primates could be a powerful tool for investigating the differentiation potential in vitro and in vivo for preclinical research.
View Article and Find Full Text PDFThe thymus provides a unique cellular and hormonic microenvironment for the development of immunocompetent T cells. Thymic polypeptides have been widely used clinically for the treatment of tumors, infectious diseases and immune deficiency diseases. They have already shown the ability to stimulate the maturation of hematopoietic stem cells towards the CD3+CD4+ T cell lineage.
View Article and Find Full Text PDFThe full potential of embryonic stem (ES) cells to generate precise cell lineages and complex tissues can be best realized when they are differentiated in vivo-i.e. in developing blastocysts.
View Article and Find Full Text PDFHuman mesenchymal stem cells (hMSC) are a population of multipotent cells that can differentiate into osteoblasts, chondrocytes, adipocytes, and other cells. The exact mechanism governing the differentiation of hMSC into osteoblasts remains largely unknown. Here, we analyzed protein expression profiles of undifferentiated as well as osteogenic induced hMSC using 2-D gel electrophoresis (2-DE), mass spectrometry (MS), and peptide mass fingerprinting (PMF) to investigate the early gene expression in osteoblast differentiation.
View Article and Find Full Text PDFEmbryonic stem cells can proliferate indefinitely and are capable of differentiating into derivatives of all three embryonic germ layers in vitro, including the neural lineage. The main objective of this study is to test the effects of neural stem cell conditioned medium on the neural differentiation of mouse embryonic stem cells. When cultured in neural stem cell conditioned medium, mouse embryonic stem cells can form floating cell spheres composed of many nestin-positive cells.
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