Search results for "Acellular"
showing 10 items of 1986 documents
Oro-gustatory perception of dietary lipids and calcium signaling in taste bud cells are altered in nutritionally obesity-prone Psammomys obesus.
2013
Since the increasing prevalence of obesity is one of the major health problems of the modern era, understanding the mechanisms of oro-gustatory detection of dietary fat is critical for the prevention and treatment of obesity. We have conducted the present study on Psammomys obesus, the rodent desert gerbil which is a unique polygenic natural animal model of obesity. Our results show that obese animals exhibit a strong preference for lipid solutions in a two-bottle test. Interestingly, the expression of CD36, a lipido-receptor, in taste buds cells (TBC), isolated from circumvallate papillae, was decreased at mRNA level, but remained unaltered at protein level, in obese animals. We further st…
Matrix-mediated canal formation in primmorphs from the sponge Suberites domuncula involves the expression of a CD36 receptor-ligand system.
2004
Sponges (Porifera), represent the phylogenetically oldest metazoan phylum still extant today. Recently, molecular biological studies provided compelling evidence that these animals share basic receptor/ligand systems, especially those involved in bodyplan formation and in immune recognition, with the higher metazoan phyla. An in vitro cell/organ-like culture system, the primmorphs, has been established that consists of proliferating and differentiating cells, but no canals of the aquiferous system. We show that after the transfer of primmorphs from the demosponge Suberites domuncula to a homologous matrix (galectin), canal-like structures are formed in these 3D-cell aggregates. In parallel …
MHCII-independent CD4+ T cells protect injured CNS neurons via IL-4
2015
A body of experimental evidence suggests that T cells mediate neuroprotection following CNS injury; however, the antigen specificity of these T cells and how they mediate neuroprotection are unknown. Here, we have provided evidence that T cell-mediated neuroprotection after CNS injury can occur independently of major histocompatibility class II (MHCII) signaling to T cell receptors (TCRs). Using two murine models of CNS injury, we determined that damage-associated molecular mediators that originate from injured CNS tissue induce a population of neuroprotective, IL-4-producing T cells in an antigen-independent fashion. Compared with wild-type mice, IL-4-deficient animals had decreased functi…
In vitro model for the activation of CD4 and CD8 T cell receptors.
2008
Previously, most models that sought to explain the misregulation of immune cell function assumed molecular similarities between the disease-causing pathogens and the host's proteins. In recent time several different models have been proposed and in this study, these concepts are compared to a new hypothesis proposing another explanation for this immune dysregulation: the possibility that the mislocalization of proteins may be responsible for autoimmune activity. Based on this hypothesis, proteins are recognized as self or non-self depending on where they appear in sufficiently high concentrations. To examine this new idea, the intracellular human proteins beta-actin, GAPDH, and hemoglobin a…
Modulation of proliferation and lymphokine secretion of murine CD4+ T cells and cloned Th1 cells by proteins of the extracellular matrix.
1997
In this study we investigated the co-stimulatory signaling capacity of diverse proteins of the extracellular matrix (ECM) for murine resting CD4+ T cells and Th1 clone cells, activated by immobilized anti-CD3 mAb. ECM proteins used in various concentrations had no effect on IL-2 production or proliferation of highly purified CD4+ T cell populations. When the preparation of CD4+ T cells contained contaminating accessory cells, IL-2 secretion and proliferation was enhanced in the presence of co-immobilized collagens or fibronectin. However, the level of proliferation attainable by added irradiated splenocytes was not reached. Using Th1 cell clone M4, enhanced production of IL-2 in the presenc…
Optimized Protocol for the Detection of Multifunctional Epitope-Specific CD4+ T Cells Combining MHC-II Tetramer and Intracellular Cytokine Staining T…
2019
Analysis of multifunctional CD4+ T cells is fundamental for characterizing the immune responses to vaccination or infection. Major histocompatibility complex (MHC)/peptide tetramers represent a powerful technology for the detection of antigen-specific T cells by specific binding to their T-cell receptor, and their combination with functional assays is fundamental for characterizing the antigen-specific immune response. Here we optimized a protocol for the detection of multiple intracellular cytokines within epitope-specific CD4+ T cells identified by the MHC class II tetramer technology. The optimal procedure for assessing the functional activity of tetramer-binding CD4+ T cells was based o…
HSP90 AND ENOS PARTIALLY CO-LOCALIZE AND CHANGE CELLULAR LOCALIZATION IN RELATION TO DIFFERENT ECM COMPONENTS IN 2D AND 3D CULTURES OF ADULT RAT CARD…
2007
BACKGROUND INFORMATION: Cultivation techniques promoting three-dimensional organization of mammalian cells are of increasing interest, since they confer key functionalities of the native ECM (extracellular matrix) with a power for regenerative medicine applications. Since ECM compliance influences a number of cell functions, Matrigel-based gels have become attractive tools, because of the ease with which their mechanical properties can be controlled. In the present study, we took advantage of the chemical and mechanical tunability of commonly used cell culture substrates, and co-cultures to evaluate, on both two- and three-dimensional cultivated adult rat cardiomyocytes, the impact of ECM c…
Versican and collagen-III expression in bronchial and pulmonary muscular arteries in COPD patients
2015
Background: We demonstrated that COPD patients have thicker bronchial and pulmonary muscular arteries (MA) compared with never and non-obstructed smokers. The composition of the extracellular matrix of these altered MA has been not fully described. Objectives: To investigate the expression of versican and collagen-III in bronchial and pulmonary MA in the lungs of mild/moderate COPD patients. Methods: Eighteen mild/moderate COPD subjects (67±8y, FEV 1 : 67±15%pred), 14 non-obstructed smokers (64±8y, FEV 1 : 95±10%pred) and 11 never-smoking controls (CTRL) (51±12y, FEV 1 : 108±15%pred) were studied. Lung tissue obtained during surgery (ethical approval obtained) was used to analyze the expres…
Effects of cadmium exposure on the ultrastructure of hepatopancreatic cells of Thais haemastoma (gastropoda, prosobranchia)
1993
Abstract Specific histopathological parameters have been proposed as good indicators of heavy-metal pollution. Hence the study of ultrastructural alterations in target organs from sentinel animals after heavy-metal exposure may provide a useful tool in understanding the cellular role in heavy-metal metabolism. The main purpose of this study was the determination of the ultrastructural changes in the different hepatopancreatic-cell types of Thais haemastoma after experimental exposure to cadmium. Specimens of this species from the Gulf of Valencia were exposed to sublethal doses of cadmium during a period of 96 h. The hepatopancreas was excised and prepared in a routine manner for electron m…
Dibutyryl cyclic AMP and adrenaline increase contractile force and 45Ca uptake in mammalian cardiac muscle
1973
The effects of dibutyryl cyclic AMP (DB-AMP; 10−3M) and adrenaline (2.2×10−6 M) on contractile force, 45Ca uptake, and total myocardial Ca concentration were investigated in electrically driven left auricles isolated from rat hearts. The experiments were performed at an extracellular Ca concentration of 0.45 mM and at low frequency of stimulation (15 beats/min). 45Ca exposure was 5 min. Under the conditions used, both drugs increased contractile force and enhanced 45Ca uptake (expressed as relative specific activity) by about 30% (DB-AMP) and 40% (adrenaline), respectively. Thus, the results provide evidence that the effects of adrenaline on 45Ca uptake in mammalian cardiac muscle can be mi…