Search results for " Transformed"
showing 10 items of 77 documents
The effects of drainage and restoration of pine mires on habitat structure, vegetation and ants
2016
Habitat loss and degradation are the main threats to biodiversity worldwide. For example, nearly 80% of peatlands in southern Finland have been drained. There is thus a need to safeguard the remaining pristine mires and to restore degraded ones. Ants play a pivotal role in many ecosystems and like many keystone plant species, shape ecosystem conditions for other biota. The effects of mire restoration and subsequent vegetation succession on ants, however, are poorly understood. We inventoried tree stands, vegetation, water-table level, and ants (with pitfall traps) in nine mires in southern Finland to explore differences in habitats, vegetation and ant assemblages among pristine, drained (30…
Apoptosis induced by a HIPK2 full-length-specific siRNA is due to off-target effects rather than prevalence of HIPK2-Δe8 isoform
2017
Small interfering RNAs (siRNAs) are widely used to study gene function and extensively exploited for their potential therapeutic applications. HIPK2 is an evolutionary conserved kinase that binds and phosphorylates several proteins directly or indirectly related to apoptosis. Recently, an alternatively spliced isoform skipping 81 nucleotides of exon 8 (Hipk2-Δe8) has been described. Selective depletion of Hipk2 full-length (Hipk2-FL) with a specific siRNA that spares the Hipk2-Δe8 isoform has been shown to strongly induce apoptosis, suggesting an unpredicted dominant-negative effect of Hipk2-FL over the Δe8 isoform. From this observation, we sought to take advantage and assessed the therape…
Metabolic Imaging in Multicellular Spheroids of Oncogene-transfected Fibroblasts
2000
Four rat embryo fibroblast (REF) cell lines with defined oncogenic transformation were used to study the relationship between tumorigenic conversion, metabolism, and development of cell death in a 3D spheroid system. Rat1 (spontaneously immortalized) and M1 ( myc-transfected) fibroblasts represent early nontumorigenic transformation stages, whereas Rat1-T1 (T24Ha- ras-transfected Rat1) and MR1 ( myc/T24Ha- ras-co-transfected REF) cells express a highly tumorigenic phenotype. Localized ATP, glucose, and lactate concentrations in spheroid median sections were determined by imaging bioluminescence. ATP concentrations were low in the nonproliferating Rat1 aggregates despite sufficient oxygen an…
Establishment and Preliminary Characterization of Three Astrocytic Cells Lines Obtained from Primary Rat Astrocytes by Sub-Cloning.
2020
Gliomas are complex and heterogeneous tumors that originate from the glial cells of the brain. The malignant cells undergo deep modifications of their metabolism, and acquire the capacity to invade the brain parenchyma and to induce epigenetic modifications in the other brain cell types. In spite of the efforts made to define the pathology at the molecular level, and to set novel approaches to reach the infiltrating cells, gliomas are still fatal. In order to gain a better knowledge of the cellular events that accompany astrocyte transformation, we developed three increasingly transformed astrocyte cell lines, starting from primary rat cortical astrocytes, and analyzed them at the cytogenet…
Cellular mechanisms of IL-17-induced blood-brain barrier disruption.
2009
Recently T-helper 17 (Th17) cells were demonstrated to disrupt the blood-brain barrier (BBB) by the action of IL-17A. The aim of the present study was to examine the mechanisms that underlie IL-17A-induced BBB breakdown. Barrier integrity was analyzed in the murine brain endothelial cell line bEnd.3 by measuring the electrical resistance values using electrical call impedance sensing technology. Furthermore, in-cell Western blots, fluorescence imaging, and monocyte adhesion and transendothelial migration assays were performed. Experimental autoimmune encephalomyelitis (EAE) was induced in C57BL/6 mice. IL-17A induced NADPH oxidase- or xanthine oxidase-dependent reactive oxygen species (ROS)…
Clonal heterogeneity of thymic B cells from early-onset myasthenia gravis patients with antibodies against the acetylcholine receptor
2014
Myasthenia gravis (MG) with antibodies against the acetylcholine receptor (AChR-MG) is considered as a prototypic autoimmune disease. The thymus is important in the pathophysiology of the disease since thymus hyperplasia is a characteristic of early-onset AChR-MG and patients often improve after thymectomy. We hypothesized that thymic B cell and antibody repertoires of AChR-MG patients differ intrinsically from those of control individuals. Using immortalization with Epstein Barr Virus and Toll-like receptor 9 activation, we isolated and characterized monoclonal B cell lines from 5 MG patients and 8 controls. Only 2 of 570 immortalized B cell clones from MG patients produced antibodies agai…
Histone acetylation deficits in lymphoblastoid cell lines from patients with Rubinstein-Taybi syndrome.
2012
Background: Rubinstein-Taybi syndrome (RSTS) is a congenital neurodevelopmental disorder defined by postnatal growth deficiency, characteristic skeletal abnormalities and mental retardation and caused by mutations in the genes encoding for the transcriptional co-activators with intrinsic lysine acetyltransferase (KAT) activity CBP and p300. Previous studies have shown that neuronal histone acetylation is reduced in mouse models of RSTS. Methods: The authors identified different mutations at the CREBBP locus and generated lymphoblastoid cell lines derived from nine patients with RSTS carrying distinct CREBBP mutations that illustrate different grades of the clinical severity in the spectrum …
Homodimeric murine interleukin-3 agonists indicate that ligand dimerization is important for high-affinity receptor complex formation.
1994
Homodimeric murine interleukin 3 (mIL-3) agonists were generated by intermolecular cystine-bonding. Steady-state binding assays and association kinetics performed at 4 degrees C using these agonists revealed specific binding to both the high- and low-affinity receptor. DSS-mediated crosslinking studies performed at 4 degrees C with agonist concentrations compatible with high-affinity receptor complex formation allowed to detect protein complexes of the alpha chain, the beta chain(s) and the high-affinity receptor complex migrating with apparent molecular weights of 90 kDa, 140 kDa, and above 180 kDa, respectively. In contrast, monomeric mIL-3 was crosslinked to the alpha chain receptor only…
T cells can present antigens such as HIV gp120 targeted to their own surface molecules
1988
To trigger class II-restricted T cells, antigen presenting cells have to capture antigens, process them and display their fragments in association with class II molecules. In most species, activated T cells express class II molecules; however, no evidence has been found that these cells can present soluble antigens. This failure may be due to the inefficient capture, processing or display of antigens in a stimulatory form by T-cells. The capture of a soluble antigen, which is achieved by nonspecific mechanisms in macrophages and dendritic cells, can be up to 10(3) times more efficient in the presence of surface receptors, such as surface immunoglobulin on B cells that specifically bind anti…
Herpes virus saimiri-transformed human T lymphocytes: normal functional phenotype and preserved T cell receptor signalling
1993
Herpes virus saimiri (HVS), a primate herpes virus, transforms human CD4+ and CD8+ T lymphocytes to continuous growth in vitro. We have previously shown that HVS-transformed human T cells (HVS-T cells) respond to stimulation via CD2 with autocrine growth. In the present study we have investigated the functional characteristics of HVS-T cells. We describe that these cells can perform all the functions of normal T cells, i.e. cytokine secretion, cytotoxicity, and exocytosis of granule esterases. All these activities can be triggered via CD2 by binding to its natural ligand or via the TCR, e.g. by anti-TCR antibodies, by recognition of a bacterial superantigen and by MHC-restricted recognition…