Search results for "Cell adhesion molecule"
showing 10 items of 469 documents
Vitamin K antagonism impairs the bone marrow microenvironment and hematopoiesis
2018
Abstract Vitamin K antagonists (VKAs) have been used in 1% of the world’s population for prophylaxis or treatment of thromboembolic events for 64 years. Impairment of osteoblast function and osteoporosis has been described in patients receiving VKAs. Given the involvement of cells of the bone marrow microenvironment (BMM), such as mesenchymal stem cells (MSCs) and macrophages, as well as other factors such as the extracellular matrix for the maintenance of normal hematopoietic stem cells (HSCs), we investigated a possible effect of VKAs on hematopoiesis via the BMM. Using various transplantation and in vitro assays, we show here that VKAs alter parameters of bone physiology and reduce funct…
Junctional adhesion molecules JAM-B and JAM-C promote autoimmune-mediated liver fibrosis in mice
2018
Fibrosis remains a serious health concern in patients with chronic liver disease. We recently reported that chemically induced chronic murine liver injury triggers increased expression of junctional adhesion molecules (JAMs) JAM-B and JAM-C by endothelial cells and de novo synthesis of JAM-C by hepatic stellate cells (HSCs). Here, we demonstrate that biopsies of patients suffering from primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC) or autoimmune hepatitis (AIH) display elevated levels of JAM-C on portal fibroblasts (PFs), HSCs, endothelial cells and cholangiocytes, whereas smooth muscle cells expressed JAM-C constitutively. Therefore, localization and function of JA…
Characterization and isolation of immature neurons of the adult mouse piriform cortex
2015
Physiological studies indicate that the piriform or primary olfactory cortex of adult mammals exhibits a high degree of synaptic plasticity. Interestingly, a subpopulation of cells in the layer II of the adult piriform cortex expresses neurodevelopmental markers, such as the polysialylated form of neural cell adhesion molecule (PSA-NCAM) or doublecortin (DCX). This study analyzes the nature, origin, and potential function of these poorly understood cells in mice. As previously described in rats, most of the PSA-NCAM expressing cells in layer II could be morphologically classified as tangled cells and only a small proportion of larger cells could be considered semilunar-pyramidal transitiona…
Effects of Dopamine on the Immature Neurons of the Adult Rat Piriform Cortex
2020
The layer II of the adult piriform cortex (PCX) contains a numerous population of immature neurons. Interestingly, in both mice and rats, most, if not all, these cells have an embryonic origin. Moreover, recent studies from our laboratory have shown that they progressively mature into typical excitatory neurons of the PCX layer II. Therefore, the adult PCX is considered a “non-canonical” neurogenic niche. These immature neurons express the polysialylated form of the neural cell adhesion molecule (PSA-NCAM), a molecule critical for different neurodevelopmental processes. Dopamine (DA) is a relevant neurotransmitter in the adult CNS, which also plays important roles in neural development and …
Effects of PSA Removal from NCAM on the Critical Period Plasticity Triggered by the Antidepressant Fluoxetine in the Visual Cortex.
2016
Neuronal plasticity peaks during critical periods of postnatal development and is reduced towards adulthood. Recent data suggests that windows of juvenile-like plasticity can be triggered in the adult brain by antidepressant drugs such as Fluoxetine. Although the exact mechanisms of how Fluoxetine promotes such plasticity remains unknown, several studies indicate that inhibitory circuits play an important role. The polysialylated form of the neural cell adhesion molecules (PSA-NCAM) has been suggested to mediate the effects of Fluoxetine and it is expressed in the adult brain by mature interneurons. Moreover, the enzymatic removal of PSA by neuroaminidase-N not only affects the structure of…
Metabolic syndrome enhances endoplasmic reticulum, oxidative stress and leukocyte–endothelium interactions in PCOS
2017
Polycystic ovary syndrome (PCOS) is associated with insulin resistance, which can lead to metabolic syndrome (MetS). Oxidative stress and leukocyte-endothelium interactions are related to PCOS. Our aim was to evaluate whether the presence of MetS in PCOS patients can influence endoplasmic reticulum (ER) and oxidative stress and leukocyte-endothelium interactions.This was a prospective controlled study conducted in an academic medical center. The study population consisted of 148 PCOS women (116 without/32 with MetS) and 112 control subjects (87 without / 25 with MetS). Metabolic parameters, reactive oxygen species (ROS) production, ER stress markers (GRP78, sXBP1, ATF6), leukocyte-endotheli…
The Metalloprotease Meprin β Is an Alternative β-Secretase of APP
2017
The membrane bound metalloprotease meprin β is important for collagen fibril assembly in connective tissue formation and for the detachment of the intestinal mucus layer for proper barrier function. Recent proteomic studies revealed dozens of putative new substrates of meprin β, including the amyloid precursor protein (APP). It was shown that APP is cleaved by meprin β in distinct ways, either at the β-secretase site resulting in increased levels of Aβ peptides, or at the N-terminus releasing 11 kDa, and 20 kDa peptide fragments. The latter event was discussed to be rather neuroprotective, whereas the ectodomain shedding of APP by meprin β reminiscent to BACE-1 is in line with the amyloid h…
Functional Analyses of Human T Cell Extravasation in a Humanized NOD/SCID/IL2Rγcnull Transplantation Model.
2009
Abstract Abstract 2448 Poster Board II-425 Donor lymphocyte graft engineering to avoid graft-versus-host (GVH) reactivity while improving graft-versus-leukemia (GVL) immunity remains of central interest in allogeneic hematopoietic stem cell transplantation (HSCT). However, appropriate models to evaluate experimental concepts of donor lymphocyte allograft engineering in vivo are missing. We, therefore, established a human-murine chimeric transplantation model using immunodeficient NOD/SCID/IL2Rγcnull (NSG) mice to evaluate GVH reactivity of human T cell grafts in vivo. Moreover, since mechanisms of immune functions resembling human GVH immunity have not yet been addressed in detail in these …
Lung CD11c+ cells from mice deficient in Epstein-Barr virus-induced gene 3 (EBI-3) prevent airway hyper-responsiveness in experimental asthma
2007
Epstein-Barr virus-induced gene (EBI)-3 codes for a soluble type 1 cytokine receptor homologous to the p40 subunit of IL-12 that is expressed by antigen-presenting cells following activation. Here, we analyzed the functional role of EBI-3 in a murine model of asthma associated with airway hyper-responsiveness (AHR) in ovalbumin-sensitized mice. Upon allergen challenge, EBI-3-/- mice showed less severe AHR, decreased numbers and degranulation of eosinophils and a significantly reduced number of VCAM-1+ cells in the lungs as compared to wild-type littermates. We thus analyzed lung CD11c+ cells before and after allergen challenge in these mice and found that before allergen challenge, lung CD1…
Occurrence of new neurons in the piriform cortex
2015
In a recent mini-review (Yuan et al., 2015), support is given to the idea that neurons are generated during adulthood in the mammalian piriform cortex (PC), their periventricular origin being also discussed. It is known since long time that a subpopulation of cortical layer II cells in the adult PC of rodents express immature neuronal markers such as polysialylated NCAM (PSA-NCAM; Seki and Arai, 1991; Bonfanti et al., 1992) and doublecortin (DCX; Nacher et al., 2002). These immature neurons have been found in most mammals studied so far, their occurrence being restricted to the paleocortex in rodents (Seki and Arai, 1991; Bonfanti et al., 1992; Nacher et al., 2002), and extended to neocorti…