Search results for "FIBROBLASTS"
showing 10 items of 445 documents
Splice donor site mutation in the lysosomal neuraminidase gene causing exon skipping and complete loss of enzyme activity in a sialidosis patient.
2001
Sialidosis is a lysosomal storage disease caused by the deficiency of K K-N-acetylneuraminidase (NEU1; sialidase), the key enzyme for the intralysosomal catabolism of sialylated glycoconjugates. We have identified a homozygous transversion in the last intron (IVSE +1 Gs C) in neu1 of a sialidosis patient. Sequencing of the truncated cDNA revealed an alternatively spliced neu1 transcript which lacks the complete sequence of exon 5. Skipping of exon 5 leads to a frameshift and results in a premature termination codon. This is the first description of an intronic point mutation causing a complete deficiency of the lysosomal neuraminidase activity. fl 2001 Federation of Euro- pean Biochemical S…
Hypertrophic agonists induce the binding of c-Fos to an AP-1 site in cardiac myocytes: implications for the expression of GLUT1
2003
Objectives: Serum is among the agents known to induce hypertrophy of cardiac myocytes, which occurs concomitant with an increase in AP-1-mediated transcription. We have examined if this effect correlates with changes in the relative abundance of particular AP-1 heterodimers, as their exact composition under these conditions is unknown. Furthermore, we obtained insight on the specific role of c-Fos from studying the induction of the glucose transporter GLUT1 by serum in fibroblasts. Methods: We characterised the AP-1 heterodimers expressed in neonatal cardiac myocytes by supershift electrophoretic mobility shift assay (EMSA) analysis. Quantitative changes in transcription were measured using…
Processing and Presentation of Murine Cytomegalovirus pORFm164-Derived Peptide in Fibroblasts in the Face of All Viral Immunosubversive Early Gene Fu…
2002
ABSTRACTCD8 T cells are the principal effector cells in the resolution of acute murine cytomegalovirus (mCMV) infection in host organs. This undoubted antiviral and protective in vivo function of CD8 T cells appeared to be inconsistent with immunosubversive strategies of the virus effected by early (E)-phase genesm04,m06, andm152. The so-called immune evasion proteins gp34, gp48, and gp37/40, respectively, were found to interfere with peptide presentation at different steps in the major histocompatibility complex (MHC) class I pathway of antigen processing and presentation in fibroblasts. Accordingly, they were proposed to prevent recognition and lysis of infected fibroblasts by cytolytic T…
Cytomegalovirus Encodes a Positive Regulator of Antigen Presentation
2006
ABSTRACT Murine cytomegalovirus encodes three regulators of antigen presentation to antiviral CD8 T cells. According to current paradigms, all three regulators are committed to the inhibition of the presentation of antigenic peptides. Whereas m152/gp40 catalyzes the retention of peptide-loaded major histocompatibility complex (MHC) class I molecules in a cis -Golgi compartment, m06/gp48 binds stably to class I molecules and directs them into the cellular cargo-sorting pathway of lysosomal degradation. Regulator m04/gp34 also binds stably to class I molecules, but unlike m152 and m06, it does not downmodulate MHC class I cell surface expression. It has entered the literature as a direct inhi…
Early gene m18, a novel player in the immune response to murine cytomegalovirus
2002
The identification of all antigenic peptides encoded by a pathogen, its T cell ‘immunome’, is a research aim for rational vaccine design. Screening of proteome-spanning peptide libraries or computational prediction is used to identify antigenic peptides recognized by CD8 T cells. Based on their high coding capacity, cytomegaloviruses (CMVs) could specify numerous antigenic peptides. Yet, current evidence indicates that the memory CD8 T cell response in a given haplotype is actually focused on a few viral proteins. CMVs actively interfere with antigen processing and presentation by the expression of immune evasion proteins. In the case of murine CMV (mCMV), these proteins are effectual in th…
Major Histocompatibility Complex Class I Allele-specific Cooperative and Competitive Interactions between Immune Evasion Proteins of Cytomegalovirus
2002
Cytomegaloviruses (CMVs) deploy a set of genes for interference with antigen presentation in the major histocompatibility complex (MHC) class I pathway. In murine CMV (MCMV), three genes were identified so far: m04/gp34, m06/gp48, and m152/gp40. While their function as immunoevasins was originally defined after their selective expression, this may not necessarily reflect their biological role during infection. The three immunoevasins might act synergistically, but they might also compete for their common substrate, the MHC class I complexes. To approach this question in a systematic manner, we have generated a complete set of mutant viruses with deletions of the three genes in all seven pos…
Characterization of molecular mechanisms underlying the axonal Charcot–Marie–Tooth neuropathy caused by MORC2 mutations
2019
Mutations in MORC2 lead to an axonal form of Charcot-Marie-Tooth (CMT) neuropathy type 2Z. To date, 31 families have been described with mutations in MORC2, indicating that this gene is frequently involved in axonal CMT cases. While the genetic data clearly establish the causative role of MORC2 in CMT2Z, the impact of its mutations on neuronal biology and their phenotypic consequences in patients remains to be clarified. We show that the full-length form of MORC2 is highly expressed in both embryonic and adult human neural tissues and that Morc2 expression is dynamically regulated in both the developing and the maturing murine nervous system. To determine the effect of the most common MORC2…
Glial precursors clear sensory neuron corpses during development via Jedi-1, an engulfment receptor
2009
During the development of peripheral ganglia, 50% of the neurons that are generated undergo apoptosis. How the massive numbers of corpses are removed is unknown. We found that satellite glial cell precursors are the primary phagocytic cells for apoptotic corpse removal in developing mouse dorsal root ganglia (DRG). Confocal and electron microscopic analysis revealed that glial precursors, rather than macrophages, were responsible for clearing most of the dead DRG neurons. Moreover, we identified Jedi-1, an engulfment receptor, and MEGF10, a purported engulfment receptor, as homologs of the invertebrate engulfment receptors Draper and CED-1 expressed in the glial precursor cells. Expression …
Oligosaccharide and Ganglioside Neuraminidase Activities of Mucolipidosis I (Sialidosis) and Mucolipidosis II (I-Cell Disease) Fibroblasts
1979
Fibroblasts cultured from the skin of patients with the genetic diseases mucolipidosis I and mucolipidosis II were found deficient in a neuraminidase specific for both an α23 and and α2 6 type of neuraminosyl linkage of sialyl oligosaccharides. Obligate heterozygotes (parents) showed an intermediate activity in mucolipidosis I, but a normal one in mucolipidosis II. The neuraminidase activity of mucolipidosis I fibroblasts towards gangliosides, measured at pH 4.5 in the presence of Triton X-100, was within the range of normal controls with gangliosides Gm3 and GD3, but somewhat diminished with a bovine brain ganglioside preparation. In mucolipidosis II, neuraminidase activity was markedly de…
Influence of E-smoking liquids on human periodontal ligament fibroblasts.
2014
Introduction: Over the last years, electronic cigarettes (ECs) have become more popular, particularly in individuals who want to give up smoking tobacco. The aim of the present study was to assess the influence of the different e-smoking liquids on the viability and proliferation of human periodontal ligament fibroblasts. Method and materials: For this study six test solutions with components from ECs were selected: lime-, hazelnut- and menthol-flavored liquids, nicotine, propylene glycol, and PBS as control group. The fibroblasts were incubated up to 96 h with the different liquids, and cell viability was measured by using the PrestoBlue® reagent, the ATP detection and the migration assay.…