Search results for "Fibronectins"
showing 10 items of 89 documents
IL1β Induces Mesenchymal Stem Cells Migration and Leucocyte Chemotaxis Through NF-κB
2012
Mesenchymal stem cells are often transplanted into inflammatory environments where they are able to survive and modulate host immune responses through a poorly understood mechanism. In this paper we analyzed the responses of MSC to IL-1β: a representative inflammatory mediator. Microarray analysis of MSC treated with IL-1β revealed that this cytokine activateds a set of genes related to biological processes such as cell survival, cell migration, cell adhesion, chemokine production, induction of angiogenesis and modulation of the immune response. Further more detailed analysis by real-time PCR and functional assays revealed that IL-1β mainly increaseds the production of chemokines such as CC…
Chemokine stromal cell-derived factor-1alpha modulates VLA-4 integrin-dependent adhesion to fibronectin and VCAM-1 on bone marrow hematopoietic proge…
2001
Stromal cell-derived factor-1alpha (SDF-1alpha) is a potent chemoattractant for hematopoietic progenitor cells (HPC), suggesting that it could play an important role during their migration within or to the bone marrow (BM). The integrin VLA-4 mediates HPC adhesion to BM stroma by interacting with CS-1/fibronectin and VCAM-1. It is required during hematopoiesis and homing of HPC to the BM. As HPC migration in response to SDF-1alpha might require dynamic regulation of integrin function, we investigated if SDF-1alpha could modulate VLA-4 function on BM CD34(hi) cells.CD34(hi) BM cells and hematopoietic cell lines were tested for the effect of SDF-1alpha on VLA-4-dependent adhesion to CS-1/fibr…
Mammary-derived growth inhibitor (MDGI) interacts with integrin α-subunits and suppresses integrin activity and invasion
2010
The majority of mortality associated with cancer is due to formation of metastases from the primary tumor. Adhesion mediated by different integrin heterodimers has an important role during cell migration and invasion. Protein interactions with the β1-integrin cytoplasmic tail are known to influence integrin affinity for extracellular ligands, but regulating binding partners for the α-subunit cytoplasmic tails have remained elusive. In this study, we show that mammary-derived growth inhibitor (MDGI) (also known as FABP-3 or H-FABP) binds directly to the cytoplasmic tail of integrin α-subunits and its expression inhibits integrin activity. In breast cancer cell lines, MDGI expression correlat…
Differential inhibition of renal cancer cell invasion mediated by fibronectin, collagen IV and laminin.
2000
Invasion of tumor cells into the extracellular matrix is an essential step in the formation of metastases in renal cancer. Cell adhesion molecules such as beta(1)-integrins, which bind to the RGD sequence (arginine-glycine-asparagine) and CD44 are involved in this process. We examined the invasion of a renal carcinoma cell line (CCF-RC1) into the extracellular matrix compounds fibronectin, collagen IV and laminin and the effect of TGFbeta and IFNgamma on this process. The inhibitory effect of an antibody against the beta(1)-subunit of integrins (CD29), as well as a pentapeptide including the RGD sequence, was also evaluated. A micro-chemotaxis chamber, including a polycarbonate membrane wit…
Genetic abrogation of the fibronectin-α5β1 integrin interaction in articular cartilage aggravates osteoarthritis in mice.
2018
The balance between synthesis and degradation of the cartilage extracellular matrix is severely altered in osteoarthritis, where degradation predominates. One reason for this imbalance is believed to be due to the ligation of the α5β1 integrin, the classic fibronectin (FN) receptor, with soluble FN fragments instead of insoluble FN fibrils, which induces matrix metalloproteinase (MMP) expression. Our objective was to determine whether the lack of α5β1-FN binding influences cartilage morphogenesis in vivo and whether non-ligated α5β1 protects or aggravates the course of osteoarthritis in mice. We engineered mice (Col2a-Cre;Fn1RGE/fl), whose chondrocytes express an α5β1 binding-deficient FN, …
Alternative splicing products of the tenascin gene distinguish rat liver fat storing cells from arterial smooth muscle cells and skin fibroblasts
1992
Abstract Fat storing-(Ito-)cells (FSC) transform into a myofibroblast-like cell type during liver fibrogenesis. A similar development can be observed in cell culture. At the moment, a definite marker to differentiate transformed FSC from smooth muscle cells (SMC) is not available. We recently found that FSC, SMC and skin fibroblasts (SF) synthesize tenascin, a novel matrix protein. As it is reported that various tissues express different tenascin forms by the mechanism of alternative pre-mRNA splicing, we analyzed the tenascin transcripts in these cell types. Total RNA extracted from cultured FSC, SMC and SF, analyzed by Northern blot hybridization, showed a 7.2 kb transcript in FSC, a 8.7 …
Material-driven fibronectin assembly rescues matrix defects due to mutations in collagen IV in fibroblasts
2020
Basement membranes (BMs) are specialised extracellular matrices that provide structural support to tissues as well as influence cell behaviour and signalling. Mutations in COL4A1/COL4A2, a major BM component, cause a familial form of eye, kidney and cerebrovascular disease, including stroke, while common variants in these genes are a risk factor for intracerebral haemorrhage in the general population. These phenotypes are associated with matrix defects, due to mutant protein incorporation in the BM and/or its absence by endoplasmic reticulum (ER) retention. However, the effects of these mutations on matrix stiffness, the contribution of the matrix to the disease mechanism(s) and its effects…
Loss of surface fibronectin after infection of cultured cells by HSV-1 and 2
1985
Fibronectin is lost from the surface of HSV infected cells during cell rounding. In order to investigate also the fate of fibronectin during the process of HSV-induced cell-fusion, BHK, Vero as well as primary or secondary rabbit kidney cells were infected with HSV-1 strains producing cell-fusion. By immunofluorescence and immunoelectron microscopy a considerable loss of fibronectin after HSV infection could be demonstrated leaving only irregular clumps of fibronectin containing virus particles on the cell surface. Decrease and disarrangement of fibronectin was similar during cell rounding and cell fusion. Loss of Fibronectin was closely connected with the two types of the cytopathic effect…
Cloning of aas, a gene encoding a Staphylococcus saprophyticus surface protein with adhesive and autolytic properties.
1998
A gene encoding a novel cell wall-associated protein of Staphylococcus saprophyticus that binds fibronectin and to sheep erythrocytes has been cloned and sequenced. The 4392 bp open reading frame codes for an amino acid sequence that is quite similar to the Atl, an autolysin, of Staphylococcus aureus and to the AtlE of S. epidermidis. The two regions of most pronounced homology code for an N-acetyl-muramyl-L-alanine amidase and for an endo-beta-N-acetyl-D-glucosaminidase. The cloned protein lysed cells of S. saprophyticus and Micrococcus luteus exogenously. Subcloning localized the enzymatic activities to the regions of high homology and demonstrated that the interposed sequence is responsi…
Modulation of Irisin and Physical Activity on Executive Functions in Obesity and Morbid obesity
2016
Whether the executive profile is different between obesity (OB) and morbid obesity (MO) remains unclear. Recent evidence suggests that physical activity (PA) can act as a cognitive enhancer. Irisin is a recently discovered hormone associated with some of the positive effects of PA. The objective of the study was to investigate the executive profile in OB and MO, and to explore the role of PA and irisin. 114 participants were included (21 OB, 44 MO and 49 healthy controls-HC) in the study and assessed with the Wisconsin Card Sorting Test, Stroop Color and Word Test, and Iowa Gambling Task. All participants were female, aged between 18 and 60 years. Results showed a similar dysfunctional prof…