Search results for "cell separation"
showing 10 items of 122 documents
Three distinct types of voltage-dependent K+ channels are expressed by Müller (glial) cells of the rabbit retina.
1994
There is ample evidence that retinal radial glial (Müller) cells play a crucial role in retinal ion homeostasis. Nevertheless, data on the particular types of ion channels mediating this function are very rare and incomplete; this holds especially for mammalian Müller cells. Thus, the whole-cell variation of the patch-clamp technique was used to study voltage-dependent currents in Müller cells from adult rabbit retinae. The membrane of Müller cells was almost exclusively permeable to K+ ions, as no significant currents could be evoked in K(+)-free internal and external solutions, external Ba2+ (1 mM) reversibly blocked most membrane currents, and external Cs+ ions (5 mM) blocked all inward …
A new method to isolate microglia from adult mice and culture them for an extended period of time
2009
As the major immuno-competent cells of the brain, microglia are highly implicated in neuro-protection as well as in neurodegeneration. Therefore, they are of key interest for research on numerous CNS diseases. Currently, to model inflammation in the brain, microglial cell lines or primary microglia prepared from embryonic or neo-natal rodents are widely used. However, these in vitro microglial models are not suitable for research in the field of neuro-degenerative diseases where aging is a crucial parameter. Only a few in vitro studies on aged microglia have been published so far, most of which use ex vivo microglia which cannot be kept in culture for prolonged periods of time. In the prese…
Cell cooperation in coelomocyte cytotoxic activity of Paracentrotus lividus coelomocytes
2007
The coelomic fluid from the sea urchin Paracentrotus lividus contains several coelomocyte types including amoebocytes and uncoloured spherulocytes involved in immune defences. In the present paper, we show a Ca(2+)-dependent cytotoxic activity for the unfractionated coelomocytes assayed in vitro, with rabbit erythrocytes and the K562 tumour cell line. In a plaque-forming assay, whole coelomocyte preparations as well as density gradient separated coelomocyte populations revealed that cell populations enriched in uncoloured spherulocytes, exerted high cytotoxic activity by releasing lysins in the presence of amoebocytes. This cooperative effect could be dependent on soluble factors released b…
Changes in the Transcriptome Profiles of Human Amnion-Derived Mesenchymal Stromal/Stem Cells Induced by Three-Dimensional Culture: A Potential Primin…
2022
Mesenchymal stromal/stem cells (MSCs) are believed to function in vivo as a homeostatic tool that shows therapeutic properties for tissue repair/regeneration. Conventionally, these cells are expanded in two-dimensional (2D) cultures, and, in that case, MSCs undergo genotypic/phenotypic changes resulting in a loss of their therapeutic capabilities. Moreover, several clinical trials using MSCs have shown controversial results with moderate/insufficient therapeutic responses. Different priming methods were tested to improve MSC effects, and three-dimensional (3D) culturing techniques were also examined. MSC spheroids display increased therapeutic properties, and, in this context, it is crucial…
Identification and purification of human erythroid progenitor cells by monoclonal antibody to the transferrin receptor (T� 67)
1988
Anti-TU 67 is a murine monoclonal antibody that recognizes the transferrin receptor. With respect to hematopoietic cells TU 67 is expressed by human multipotent colony-forming cells (CFU-Mix), erythroid progenitor cells (BFU-E and CFU-E) and a fraction of granulocyte/monocyte colony forming cells, but is not expressed by mature hematopoietic cells including erythrocytes, platelets, lymphocytes, and peripheral blood myeloid cells. The TU 67-positive fraction of normal bone marrow, separated by fluorescence-activated cell sorting (FACS) or immune rosettes, contained 87% of the erythroid progenitor cells. Erythroid progenitor cells were enriched up to 50-fold by using a combination of monoclon…
OPLA scaffold, collagen I, and horse serum induce a higher degree of myogenic differentiation of adult rat cardiac stem cells
2009
In the last few years, a major goal of cardiac research has been to drive stem cell differentiation to replace damaged myocardium. Several research groups have attempted to differentiate potential cardiac stem cells (CSCs) using bi- or three-dimensional systems supplemented with growth factors or molecules acting as differentiating substances. We hypothesize that these systems failed to induce a complete differentiation because they lacked an architectural space. In the present study, we isolated a pool of small proliferating and fibroblast-like cells from adult rat myocardium. The phenotype of these cells was assessed and the characterized cells were cultured in a collagen I/OPLA scaffold …
Efficient selection of silenced primary cells by flow cytometry
2007
Background: RNA interference has emerged as a new and potent tool to knockdown the expression of target genes and to investigate their functions. For short time experiments with mammalian cell lines, RNA interference is typically induced by transfecting small interfering RNAs (siRNAs). Primary cells constitute important experimental systems in many studies because of their similarity to their in vivo counterparts; however, transfection of these cells has been found to be difficult. As a consequence, RNA interference of primary cells may result in mixed phenotypes because of the simultaneous presence in the same preparation of transfected and nontransfected cells. This may be particularly in…
Neuronal nitric oxide synthase modulates maturation of human dendritic cells.
2010
AbstractDendritic cells (DCs) are the most potent APCs of the immune system. Understanding the intercellular and intracellular signaling processes that lead to DC maturation is critical for determining how these cells initiate T cell-mediated immune processes. NO synthesized by the inducible NO synthase (iNOS) is important for the function of murine DCs. In our study, we investigated the regulation of the arginine/NO-system in human monocyte-derived DCs. Maturation of DCs induced by inflammatory cytokines (IL-1β, TNF, IL-6, and PGE2) resulted in a pronounced expression of neuronal NOS (nNOS) but only minimal levels of iNOS and endothelial NOS were detected in human mature DCs. In addition, …
Multipotent Neural Stem Cells Reside into the Rostral Extension and Olfactory Bulb of Adult Rodents
2002
The lateral walls of the forebrain lateral ventricles are the richest source of stem cells in the adult mammalian brain. These stem cells give rise to new olfactory neurons that are renewed throughout life. The neurons originate in the subventricular zone (SVZ), migrate within the rostral extension (RE) of the SVZ along the rostral migratory stream (RMS) within tube-like structures formed of glial cells, to eventually reach the olfactory bulb (OB). We demonstrate that, contrary to the current view, multipotential (neuronal-astroglial-oligodendroglial) precursors with stem cell features can be isolated not only from the SVZ but also from the entire RE, including the distal portion within the…
Synthesis and cell surface display of class II determinants by long-term propagated rat T line cells
1987
We have investigated the capacity of the encephalitogenic BS rat T cell line bs 83 and its variant clone bs 83.III.C6 to synthesize and express RT1.B-specific class II molecule subsets defined by monoclonal antibodies (mAb) MRC-OX6 and MRC-OX3. Earlier studies had indicated that mAb MRC-OX6 recognizes three distinct molecular species: an immature oligomeric polypeptide chain complex comprised of the polymorphic subunits alpha, beta and the invariant proteins of the gamma group; a biosynthetic intermediate composed of post-translationally modified alpha, beta and gamma chain (denoted p35) and a fully glycosylated alpha, beta two-chain complex derived from the plasma membrane. MRC-OX3 was sho…