Search results for "Cell Communication"
showing 10 items of 153 documents
Lack of "Synaptic" Ribbons in the Pineal Gland of BALB/c Mice
1988
In mammalian pinealocytes "synaptic" ribbons (SR) are regularly occurring organelles that are functionally poorly understood. Since in a number of studies on the mouse pineal gland the presence of SR has not been mentioned, it was the aim of this investigation to quantitate SR in mice. BALB/c mice were chosen, which have recently been shown to have a genetic defect for melatonin synthesis. The pineals of 15 mice killed at night, when SR numbers are normally high, were examined electron microscopically, scanning an area of greater than 20,000 micron 2 per gland. In none of these pineals were SR detected. It is concluded that the lack or extreme rarity of SR in laboratory mice may be related …
MiR-33a Controls hMSCS Osteoblast Commitment Modulating the Yap/Taz Expression Through EGFR Signaling Regulation
2019
Mesenchymal stromal cells (hMSCs) display a pleiotropic function in bone regeneration. The signaling involved in osteoblast commitment is still not completely understood, and that determines the failure of current therapies being used. In our recent studies, we identified two miRNAs as regulators of hMSCs osteoblast differentiation driving hypoxia signaling and cytoskeletal reorganization. Other signalings involved in this process are epithelial to mesenchymal transition (EMT) and epidermal growth factor receptor (EGFR) signalings through the regulation of Yes-associated protein (YAP)/PDZ-binding motif (TAZ) expression. In the current study, we investigated the role of miR-33a family as a (…
In vitro models of BBB: a tool for the analysis of cell to cell communication in the brain
2008
Many researchers have been trying to set in vitro models of the blood-brain barrier (BBB) aimed at analyzing, in simplified terms, the molecular mechanisms responsible for formation, maintenance and functioning of the BBB, as well as the capability of specific drugs and pro-drugs to cross BBB. We did it, starting with a simpler system of co-culture that allowed us to analyze the effects of neurons on differentiation of brain capillary endothelial cells (RBE4.B cells) in culture, and setting then a more complex model, that includes three cell types (endothelial cells, neurons and astrocytes). The reciprocal geometrical organization of brain cells in this model system is similar to the one ob…
Osteoclast Immunosuppressive Effects in Multiple Myeloma: Role of Programmed Cell Death Ligand 1
2018
Immunomodulatory drugs and monoclonal antibody-based immunotherapies have significantly improved the prognosis of the patients with multiple myeloma (MM) in the recent years. These new classes of reagents target malignant plasma cells (PCs) and further modulate the immune microenvironment, which prolongs anti-MM responses and may prevent tumor occurrence. Since MM remains an incurable cancer for most patients, there continues to be a need to identify new tumor target molecules and investigate alternative cellular approaches using gene therapeutic strategies and novel treatment mechanisms. Osteoclasts (OCs), as critical multi-nucleated large cells responsible for bone destruction in >80% …
Are Toll-like receptors and decoy receptors involved in the immunopathogenesis of systemic lupus erythematosus and lupus-like syndromes?
2011
In this paper we focus our attention on the role of two families of receptors, Toll-like receptors (TLR) and decoy receptors (DcR) involved in the generation of systemic lupus erythematosus (SLE) and lupus-like syndromes in human and mouse models. To date, these molecules were described in several autoimmune disorders such as rheumatoid arthritis, antiphospholipids syndrome, bowel inflammation, and SLE. Here, we summarize the findings of recent investigations on TLR and DcR and their role in the immunopathogenesis of the SLE.
Angiotensin II induces leukocyte-endothelial cell interactions in vivo via AT(1) and AT(2) receptor-mediated P-selectin upregulation.
2000
Background —Angiotensin II (Ang II) plays a critical role in the development of vascular lesions in hypertension, atherosclerosis, and several renal diseases. Because Ang II may contribute to the leukocyte recruitment associated with these pathological states, the aim of the present study was to assess the role of Ang II in leukocyte–endothelial cell interactions in vivo. Methods and Results —Intravital microscopy of the rat mesenteric postcapillary venules was used. Sixty minutes of superfusion with 1 nmol/L Ang II induced a significant increase in leukocyte rolling flux (83.8±20.7 versus 16.4±3.1 cells/min), adhesion (11.4±1.0 versus 0.8±0.5 cells/100 μm), and emigration (4.0±0.7 versus …
Retinoid X receptor agonists impair arterial mononuclear cell recruitment through peroxisome proliferator-activated receptor-γ activation.
2012
Abstract Mononuclear cell migration into the vascular subendothelium constitutes an early event of the atherogenic process. Because the effect of retinoid X receptor (RXR)α on arterial mononuclear leukocyte recruitment is poorly understood, this study investigated whether RXR agonists can affect this response and the underlying mechanisms involved. Decreased RXRα expression was detected after 4 h stimulation of human umbilical arterial endothelial cells with TNF-α. Interestingly, under physiological flow conditions, TNF-α–induced endothelial adhesion of human mononuclear cells was concentration-dependently inhibited by preincubation of the human umbilical arterial endothelial cells with RXR…
Chronic periodontitis impairs polymorphonuclear leucocyte-endothelium cell interactions and oxidative stress in humans.
2018
Aim To evaluate the relationship between oxidative stress parameters in polymorphonuclear leucocytes (PMNs) and PMN-endothelial cell interactions in patients with chronic periodontitis (CP) according to different degrees of severity of the disease. Materials and methods For this cross-sectional study, 182 subjects were divided into four groups according to degree of CP: without CP (n = 37), mild CP (n = 59), moderate CP (n = 51), and severe CP (n = 35). We determined anthropometric and biochemical variables, periodontal parameters, inflammatory markers, oxidative stress parameters (superoxide and mitochondrial membrane potential), and PMN-endothelium cell interactions (rolling flux, velocit…
The neuroimmune link in the bronchus-associated lymphoid tissue (BALT) of cat and rat: peptides and neural markers.
1991
This light microscopic immunohistochemical study investigates the distribution and target interrelations of nerve fibers in bronchus-associated lymphoid tissues (BALT) of rat and cat by using antisera against (1) the polyneuronal marker protein gene product 9.5 (PGP 9.5), (2) selected opioid and nonopioid peptides, and (3) the marker enzymes tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH). In both species, a similar distribution pattern of PGP, peptide, and catecholamine enzyme immunoreactive was observed. Anti-PGP 9.5 stained all nerve fibers (except some smaller, calcitonin gene-related peptide-immunoreactive (CGRP-ir) fibers presumably of the C-type) throughout the differen…
Gastrin induces the interaction between human mononuclear leukocytes and endothelial cells through the endothelial expression of P-selectin and VCAM-…
2009
Gastric mucosal inflammation is frequently associated with hypergastrinemia, and a correlation exists between the level of gastrin and degree of gastritis. We have previously observed that gastrin promotes leukocyte-endothelial interactions and contributes to Helicobacter -induced inflammation in the rat mesentery. In the present study, we aimed to evaluate a possible proinflammatory activity of gastrin in humans. The interaction between human leukocytes [U-937 cells, peripheral blood polymorphonuclear (PMN), and peripheral blood mononuclear (PBMC) cells] and human umbilical vein endothelial cells (HUVEC) was analyzed in static and dynamic conditions. The endothelial expression of adhesion …