Search results for "Microscopy"
showing 10 items of 3390 documents
Characterization of T–cell subclasses and NK–cells in lysosomal disorders by immuno–electron microscopy
1994
Previous studies have shown that B and T lymphocytes are affected in lysosomal disorders. The aim of this study was to investigate the involvement of subclasses of T lymphocytes and natural killer cells in lysosomal diseases. CD4+, CD8+, and CD56+ cells were immunomagnetically separated from peripheral blood mononuclear cells in 10 patients with various lysosomal diseases--including one patient each with infantile, late infantile, and juvenile neuronal ceroid-lipfuscinoses, two patients with mucopolysaccharidosis (MPS) type I and four patients with MPS type III, and one patient with mucolipidosis type II; all lymphocytes were studied by light and electron microscopy. Respective vacuolar or …
Functionalized Polystyrene Nanoparticles Trigger Human Dendritic Cell Maturation Resulting in Enhanced CD4+T Cell Activation
2012
Nanoparticles (NP) represent a promising tool for biomedical applications. Here, sulfonate- and phosphonate-functionalized polystyrene NP are analyzed for their interaction with human monocyte-derived dendritic cells (DC). Immature dendritic cells (iDC) display a higher time- and dose-dependent uptake of functionalized polystyrene NP compared to mature dendritic cells (mDC). Notably, NP induce an enhanced maturation of iDC but not of mDC (upregulation of stimulatory molecules and cytokines). NP-triggered maturation results in a significantly enhanced T cell stimulatory capacity (increased CD4(+) T cell proliferation and IFN-γ production), indicating a shift to a pronounced Th1 response. Imm…
Nanoparticles and antigen-specific T-cell therapeutics: A comprehensive study on uptake and release
2015
Aim: T lymphocytes are used as cellular therapeutics in many disease entities including cancer. We investigated the uptake and retention of nanoparticles (NPs) by these nonphagocytic cells. Materials & methods: Uptake, release and toxicity of various polymeric NP preparations were analyzed by flow cytometry, confocal laser scanning microscopy and transmission electron microscopy. T-cell effector functions were measured using IFN-γ-ELISPOT and 51Chromium-release assays. Results: Amino-functionalized NPs were efficiently ingested by antigen-specific T cells without adversely influencing effector functions. NPs were stored in membrane-surrounded vesicles, with major proportions released e…
HSP90 AND ENOS PARTIALLY CO-LOCALIZE AND CHANGE CELLULAR LOCALIZATION IN RELATION TO DIFFERENT ECM COMPONENTS IN 2D AND 3D CULTURES OF ADULT RAT CARD…
2007
BACKGROUND INFORMATION: Cultivation techniques promoting three-dimensional organization of mammalian cells are of increasing interest, since they confer key functionalities of the native ECM (extracellular matrix) with a power for regenerative medicine applications. Since ECM compliance influences a number of cell functions, Matrigel-based gels have become attractive tools, because of the ease with which their mechanical properties can be controlled. In the present study, we took advantage of the chemical and mechanical tunability of commonly used cell culture substrates, and co-cultures to evaluate, on both two- and three-dimensional cultivated adult rat cardiomyocytes, the impact of ECM c…
Immunogold Labeling to Detect Streptococcus pyogenes Cas9 in Cell Culture and Tissues by Electron Microscopy
2019
Final publication is available from Mary Ann Liebert, Inc., publishers https://doi.org/10.1089/crispr.2019.0032. The CRISPR-Cas9 system is a powerful and yet precise DNA-editing tool in rapid development. By combining immunogold labeling and electron microscopy with the novel CRISPR-Cas9 system, we propose a new method to gain insight into the biology of this tool. In this study, we analyzed different Cas9-induced systems such as HEK293T cell line, murine oligodendrocyte progenitor cells, brain and liver to detect Cas9 expression by immunoelectron microscopy. Our results show that while Cas9 expression could be found in the nuclei and nucleopores of transfected HEK293T cells, in transfected…
Glutamatergic projection from the nucleus incertus to the septohippocampal system
2012
Abstract Recent findings support a relevant role of the nucleus incertus in the control of the hippocampal activity through the modulation of theta rhythm. Previous studies from our group have shown that this nucleus is a critical relay between reticularis pontis oralis and the medial septum/diagonal band, regarded as the main activator and the pacemaker of the hippocampal oscillations, respectively. Besides, the nucleus incertus is highly linked to activated states related to the arousal response. The neurotransmission of the nucleus incertus, however, remains uncertain. Only GABA and the neuromodulator relaxin 3 are usually considered to be involved in its contribution to the septohippoca…
Soluble guanylyl cyclase appears in a specific subset of periglomerular cells in the olfactory bulb
2005
In the brain, nitric oxide acts as an atypical messenger in cellular nonsynaptic transmission. In the olfactory bulb, this gas is produced at the level of the olfactory glomeruli by a subpopulation of periglomerular cells that participates in the first synaptic relay of the olfactory information between the olfactory nerve and the dendritic tufts of principal cells. It has been proposed that nitric oxide modulates intraglomerular synaptic integration of sensory inputs, but its specific role in the glomerular circuitry remains to be understood. In this article, we demonstrate that, in the glomerular circuits, a specific subset of periglomerular cells, most of them expressing the calcium bind…
VIP-containing deep short-axon cells of the olfactory bulb innervate interneurons different from granule cells
2003
This study investigates the targets of the population of vasoactive intestinal polypeptide (VIP)-containing deep short-axon cells of the rat olfactory bulb (OB), combining single- and double-immunocytochemical approaches under light and electron microscopy. It has been assumed that deep short-axon cells innervate granule cells in the mammalian OB, but their synaptic connectivity has not been demonstrated to date. Our results indicate that, instead of the accepted scheme of the bulbar circuitry, VIP-containing deep short-axon cells are gamma-aminobutyric acid (GABA)ergic interneurons specialized in the selective innervation of other GABAergic deep short-axon cells. Their axons contact with t…
Where Is the Most Hydrophobic Region? Benzopurpurine Self-Assembly at the Calcite–Water Interface
2017
Control of molecular self-assembly at solid–liquid interfaces is challenging due to the complex interplay between molecule–molecule, molecule–surface, molecule–solvent, surface–solvent, and solvent–solvent interactions. Here, we use in-situ dynamic atomic force microscopy to study the self-assembly of Benzopurpurine 4B into oblong islands with a highly ordered inner structure yet incommensurate with the underlying calcite (10.4) surface. Molecular dynamics and free energy calculations provide insights by showing that Benzopurpurine 4B molecules do not anchor to the surface directly but instead assemble on top of the second hydration layer. This seemingly peculiar behavior was then rationali…
Stabilization of Polar Step Edges on Calcite (10.4) by the Adsorption of Congo Red
2015
In this work, we present the stabilization of polar step edges along the [010] direction of calcite (10.4) by the presence of a water-soluble organic molecule, namely Congo Red. While characteristic etch pits are observed on the surface in the absence of the additive, no etch pits can be found in the presence of the additive. Using atomic force microscopy, we can directly follow the restructuring of the surface. Upon addition of Congo Red, the charge-neutral step edges confining the characteristic etch pits vanish, while polar step edges along the [010] direction appear on the surface, which are entirely decorated by well-ordered molecular islands of the additive. After the restructuring ha…