Search results for "Cell Differentiation"
showing 10 items of 907 documents
Special Program of Differentiation Expressed in Keratinocytes of Human Haarscheiben: An Analysis of Individual Cytokeratin Polypeptides
1993
Human haarscheiben, epidermal Merkel cell-rich sensory organs of hairy skin, were studied for the expression of various cytokeratin (CK) polypeptides and other epithelial and neuronal differentiation markers by applying immunoperoxidase and immunofluorescence microscopy to frozen sections and by two-dimensional gel electrophoresis. The basal clusters of Merkel cells were specifically detected by antibodies against CK 20. Haarscheiben keratinocytes were unique mainly by the prominent expression of CK 17 in the lower and middle layers. Further differences as compared to keratinocytes of usual epidermis included the enlargement of the basal compartment, characterized by the expression of CK 5 …
Blood coagulation factor XII drives adaptive immunity during neuroinflammation via CD87-mediated modulation of dendritic cells
2016
Aberrant immune responses represent the underlying cause of central nervous system (CNS) autoimmunity, including multiple sclerosis (MS). Recent evidence implicated the crosstalk between coagulation and immunity in CNS autoimmunity. Here we identify coagulation factor XII (FXII), the initiator of the intrinsic coagulation cascade and the kallikrein–kinin system, as a specific immune cell modulator. High levels of FXII activity are present in the plasma of MS patients during relapse. Deficiency or pharmacologic blockade of FXII renders mice less susceptible to experimental autoimmune encephalomyelitis (a model of MS) and is accompanied by reduced numbers of interleukin-17A-producing T cells.…
Review with novel markers facilitates precise categorization of 41 cases of diagnostically challenging, “undifferentiated small round cell tumors”. A…
2017
Abstract Background Despite extensive immunohistochemical (IHC) and molecular studies combined with morphologic findings, a group of round/ovoid cell tumors histologically similar to Ewing sarcomas (ES) but lacking EWSR1-rearrangements may remain unclassifiable. Design We retrospectively analyzed 41 Ewing-like tumors (formalin-fixed, paraffin-embedded) previously determined as negative or non-informative for EWSR1-rearrangements by FISH and/or RT-PCR. A new histopathology revision and additional IHC and molecular analyses were carried out in order to investigate whether additional IHC and/or molecular testing in combination with the morphological findings may help in reaching a definitive d…
Role of p16INK4a and BMI-1 in oxidative stress-induced premature senescence in human dental pulp stem cells
2017
Human dental pulp stem cells (hDPSCs) are a source for cell therapy. Before implantation, an in vitro expansion step is necessary, with the inconvenience that hDPSCs undergo senescence following a certain number of passages, loosing their stemness properties. Long-term in vitro culture of hDPSCs at 21% (ambient oxygen tension) compared with 3–6% oxygen tension (physiological oxygen tension) caused an oxidative stress-related premature senescence, as evidenced by increased β-galactosidase activity and increased lysil oxidase expression, which is mediated by p16INK4a pathway. Furthermore, hDPSCs cultured at 21% oxygen tension underwent a downregulation of OCT4, SOX2, KLF4 and c-MYC factors, w…
Direct pericyte-to-neuron reprogramming via unfolding of a neural stem cell-like program
2018
Ectopic expression of defined transcription factors can force direct cell-fate conversion from one lineage to another in the absence of cell division. Several transcription factor cocktails have enabled successful reprogramming of various somatic cell types into induced neurons (iNs) of distinct neurotransmitter phenotype. However, the nature of the intermediate states that drive the reprogramming trajectory toward distinct iN types is largely unknown. Here we show that successful direct reprogramming of adult human brain pericytes into functional iNs by Ascl1 and Sox2 encompasses transient activation of a neural stem cell-like gene expression program that precedes bifurcation into distinct…
Erratum to: Donor age and long-term culture do not negatively influence the stem potential of limbal fibroblast-like stem cells
2016
In regenerative medicine the maintenance of stem cell properties is of crucial importance. Ageing is considered a cause of reduced stemness capability. The limbus is a stem niche of easy access and harbors two stem cell populations: epithelial stem cells and fibroblast-like stem cells. Our aim was to investigate whether donor age and/or long-term culture have any influence on stem cell marker expression and the profiles in the fibroblast-like stem cell population.Fibroblast-like stem cells were isolated and digested from 25 limbus samples of normal human corneo-scleral rings and long-term cultures were obtained. SSEA4 expression and sphere-forming capability were evaluated; cytofluorimetric…
Age-Related Lipid Metabolic Signature in HumanLMNA-Lipodystrophic Stem Cell-Derived Adipocytes
2015
Lamin A (LMNA)-linked lipodystrophies belong to a group of clinical disorders characterized by a redistribution of adipose tissue with a variable range of metabolic complications. The leading cause of these disorders is the nonphysiological accumulation of the lamin A precursor, prelamin A. However, the molecular mechanisms by which prelamin A induces the pathology remain unclear.The aim of this study is to use an experimental LMNA-lipodystrophy model based on human mesenchymal stem cell (hMSC)-derived adipocytes that accumulate prelamin A to gain deeper insights into the mechanisms governing these diseases.Prelamin A-induced or -noninduced hMSC-derived adipocytes were obtained from healthy…
Sex-specific phenotypical and functional differences in peripheral human Vγ9/Vδ2 T cells
2006
Abstract Vγ9/Vδ2 T cells constitute a minor proportion of human peripheral blood T cells that can expand rapidly upon infection with microbial pathogens. Vγ9/Vδ2 T cell numbers change characteristically with age, rising from birth to puberty and gradually decreasing again beyond 30 years of age. In adults, female blood donors have significantly higher levels than males, implying that circulating Vγ9/Vδ2 T cells in women remain elevated for a longer period in life and drop less strikingly than in men. This loss in men is accompanied by a substantial depletion of CD27−CD45RA− and CD27−CD45RA+ effector T cells and a parallel increase in CD27+CD45RA− central memory T cells while in women, the d…
Manifestation and ultrastructural typing of amyloid deposits in the heart
1983
Using light and electron microscopy, 65 cases of amyloid deposits in the heart were examined. Five different groups were distinguished: I. isolated atrial amyloidosis, II. senile cardiac amyloidosis, III. cardiac amyloid accompanying chronic infections and tumors, IV. cardiac amyloid accompanying plasma cell dyscrasia, V. idiopathic cardiac amyloidosis. Seen structurally, no principal differences in the precise localization of the amyloid deposits were found in any of the groups investigated. Amyloid is always deposited in the vicinity of cells with myocytic cell differentiation (i.e. the heart muscle cells, non-striated muscle cells of the vessels), whereby the relevant basement membranes …
The kinase inhibitor LS104 induces apoptosis, enhances cytotoxic effects of chemotherapeutic drugs and is targeting the receptor tyrosine kinase FLT3…
2008
Activating mutations of FLT3 are found in approximately one-third of acute myeloid leukemia (AML)-cases and are considered to represent an attractive therapeutic target. In this study, we report that the hydroxystyryl-acrylonitrile compound LS104 inhibits proliferation and induces potent cytotoxic effects in FLT3 expressing leukemic cells in vitro. Immunoblot and phosphoprotein-FACS analysis demonstrated inhibiton of phosphorylation of FLT3-ITD and of its downstream targets. In pharmacokinetic studies, a rapid and dose dependent cellular uptake of LS104 lasting up to 11h could be demonstrated. Combination of LS104 with chemotherapeutic agents markedly enhanced cytotoxic effects. Recently, a…