scholarly journals Stimulation of beta1 integrins on fibroblasts induces PDGF independent tyrosine phosphorylation of PDGF beta-receptors.

1996 ◽  
Vol 132 (4) ◽  
pp. 741-752 ◽  
Author(s):  
C Sundberg ◽  
K Rubin
Keyword(s):  
Cell Adhesion ◽  
Tyrosine Phosphorylation ◽  
Collagen Type ◽  
Collagen Gel ◽  
Collagen Type I ◽  
Receptor Activation ◽  
Type I ◽  
Integrin Subunit ◽  
Beta Receptor ◽  
Beta Receptors

We report that integrin-mediated signaling induces a rapid and transient tyrosine phosphorylation of platelet-derived growth factor (PDGF) beta-receptors in human diploid foreskin AG 1518 fibroblasts. A transient tyrosine phosphorylation of PDGF beta-receptors was evident one and two hours after cells had been plated on collagen type I and fibronectin, as well as on immobilized anti-integrin subunit IgG, but not on poly-L-lysine. In contrast EGF or PDGF alpha-receptors were not phosphorylated on tyrosine residues under these conditions. Tyrosine phosphorylation of PDGF beta-receptors induced by plating on collagen type I was inhibited by cytochalasin D and herbimycin A, unaffected by cycloheximide and enhanced by orthovanadate. Furthermore, a transient phosphorylation of PDGF beta-receptors occurred when AG 518 fibroblasts were cultured in three-dimensional collagen lattices or exposed to external strain exerted through centrifugation. The latter effect was evident already after two minutes. Clustering of cell surface beta1 integrins led to PDGF beta-receptor phosphorylation both in suspended and firmly attached AG 1518 fibroblasts. Plating of cells on collagen type I, fibronectin, and anti-beta1-integrin IgG resulted in the formation of PDGF beta-receptor aggregates as detected by immunofluorescence. Suramin or anti-PDGF-BB IgG had no effect on the plating-induced tyrosine phosphorylation of PDGF beta-receptors. PDGF-B chain mRNA, or protein, were not detected in AG 1518 fibroblasts. Our data suggest that a ligand-independent PDGF beta-receptor activation during cell adhesion and early phases of cell spreading is involved in integrin-mediated signaling in fibroblasts, and constitutes parts of a mechanism for cells to respond during the dynamic phases of externally applied tension as well as fibroblast-mediated tension during cell adhesion and collagen gel contraction.

Bacterial Endotoxin Inhibits Migration, Attachment, and Orientation of Human Gingival Fibroblasts in vitro and Delays Collagen Gel Contraction

1987 ◽  
Vol 66 (9) ◽  
pp. 1449-1455 ◽  
Author(s):  
S. Pitaru ◽  
M. Soldinger ◽  
D. Madgar ◽  
Z. Metzger
Keyword(s):  
Collagen Type ◽  
Cell Attachment ◽  
Collagen Gel ◽  
Collagen Type I ◽  
Human Gingival Fibroblasts ◽  
Bacterial Endotoxin ◽  
Type I ◽  
Gingival Fibroblasts ◽  
Collagen Gels

The purpose of this study was to assess the effect of endotoxin adsorbed to dental surfaces and to collagen type I on the migration, attachment, and orientation of human gingival fibroblasts (HGF). Transversely cut porcine tooth root slices (RS), 200 μm thick, were prepared. Half of the RS obtained were partially demineralized in EDTA. Half of the demineralized and non-demineralized RS were incubated with 400 μg/mL of endotoxin for 24 hr, whereas the other half were maintained in PBS and served as controls. Experimental and control RS were placed on confluent layers of HFG and cultured for six days. Cell migration toward and cell attachment to the periphery of the RS and the formation of oriented cell sheets were assessed by means of photographic techniques. Additionally, six-day-old cultures were fixed and processed for SEM observation. In separate experiments, the effect of endotoxin on cell attachment to collagen type I and on contraction of three-dimensional collagen gels was assessed. It was found that: (i) bacterial endotoxin inhibited migration and attachment of HGF to both demineralized and non-demineralized cementum and interfered with the development of oriented cellular structure ; (ii) the inhibitory effect was significantly more pronounced for non-demineralized than for demineralized cementum; (iii) the morphology of HGF attached to endotoxin-treated dental surfaces was altered compared with that of their controls; and (iv) bacterial endotoxin inhibited cell attachment to collagen type I and delayed the contraction of collagen gel.

Effects of Controlled Released BMP-7 on Markers of Inflammation and Degradation During the Cultivation of Human Osteoarthritic Chondrocytes

2010 ◽  
Vol 26 (4) ◽  
pp. 419-433 ◽  
Author(s):  
Karsten Gavenis ◽  
Thomas Pufe ◽  
Lars Ove Brandenburg ◽  
Katharina Schiffl ◽  
Bernhard Schmidt-Rohlfing
Keyword(s):  
Gene Expression ◽  
Collagen Type ◽  
Articular Chondrocytes ◽  
Collagen Gel ◽  
Collagen Type I ◽  
Type I ◽  
Matrix Synthesis ◽  
Gene Expressions ◽  
Markers Of Inflammation ◽  
Osteoarthritic Chondrocytes

The aim of the present study is to investigate the effects of BMP-7 released from polylactide microspheres on the appearance of various catabolic and inflammatory cytokines secreted by osteoarthritic chondrocytes cultivated in a collagen gel. Articular chondrocytes of 15 patients suffering from osteoarthritis are transferred to a collagen type-I gel. Additionally, BMP-7 encapsulated into polylactide microspheres (50 ng BMP-7/mL gel) is added. After 14 days, gene expression and protein appearance of various genes involved in matrix turnover and inflammation are investigated by immunohistochemical staining and RT-PCR and compared to untreated controls. TNF-α, MMP-13, IL-6, IL-1β, and VEGF gene expressions are decreased in the treatment group. In contrast, BMP-7-induced matrix synthesis is not affected, leaving collagen type-II (Col-II) gene expression to be elevated, while collagen type-I (Col-I) is decreased. In summary, controlled release of low concentrated BMP-7 from polylactide microspheres leads to a decrease in gene expression of the investigated inflammation and matrix degradation markers whereas matrix synthesis is induced.

Release of an invasion promoter E-cadherin fragment by matrilysin and stromelysin-1

2001 ◽  
Vol 114 (1) ◽  
pp. 111-118 ◽  
Author(s):  
V. Noe ◽  
B. Fingleton ◽  
K. Jacobs ◽  
H.C. Crawford ◽  
S. Vermeulen ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
Cell Surface ◽  
Collagen Type ◽  
Cell Aggregation ◽  
Collagen Type I ◽  
Type I ◽  
Tissue Inhibitor Of Metalloproteinases ◽  
Dependent Cell ◽  
Mcf 7 ◽  
E Cadherin

The function of many transmembrane molecules can be altered by cleavage and subsequent release of their ectodomains. We have investigated ectodomain cleavage of the cell-cell adhesion and signal-transducing molecule E-cadherin. The E-cadherin ectodomain is constitutively shed from the surface of MCF-7 and MDCKts.srcC12 cells in culture. Release of the 80 kDa soluble E-cadherin fragment is stimulated by phorbol-12-myristate-13-acetate and is inhibited by overexpression of the tissue inhibitor of metalloproteinases-2. The metalloproteinases matrilysin and stromelysin-1 both cleave E-cadherin at the cell surface and release sE-CAD into the medium. The soluble E-cadherin fragment thus released inhibits E-cadherin functions in a paracrine way, as indicated by induction of invasion into collagen type I and inhibition of E-cadherin-dependent cell aggregation. Our results, therefore, suggest a novel mechanism by which metalloproteinases can influence invasion.

Collagen type I enhances endothelin-mediated contraction and induces nonproliferating phenotype in mesangial cells

1996 ◽  
Vol 270 (6) ◽  
pp. F960-F970 ◽  
Author(s):  
T. Miralem ◽  
C. I. Whiteside ◽  
D. M. Templeton
Keyword(s):  
Light Chain ◽  
Myosin Light Chain ◽  
Collagen Type ◽  
Mesangial Cells ◽  
Collagen Gel ◽  
Collagen Type I ◽  
Cell Number ◽  
Type I ◽  
Total Dna ◽  
Glomerular Extracellular Matrix

Accumulation of glomerular extracellular matrix is a characteristic accompaniment of mesangial cell proliferation in progressive renal disease. We examined how growth on several matrices affected the proliferative phenotype of cultured rat mesangial cells. Compared with growth on plastic, Matrigel, or mesangial matrix, collagen type I caused a decreased cell number at 72 h, decreased total DNA per culture, and a decrease in the incorporation of [3H]thymidine during S phase in cells released from quiescence. These antiproliferative and antimitogenic effects of collagen type I required growth on a collagen gel; soluble collagen or collagen fragments were without effect. Because a number of agents elicit both proliferative and contractile responses in mesangial cells, we examined the effect of growth on collagen on contractility. Compared with plastic, cells grown on collagen type I were more contractile, showed a higher Ca2+ signal in response to endothelin, and responded to endothelin with a more rapid myosin light-chain kinase-dependent phosphorylation of myosin light chain. We conclude that growth on a collagen type I gel uncouples contractility from a proliferative response in mesangial cells, suppressing proliferation while enhancing contraction and Ca2+ signaling in response to endothelin.

scholarly journals Nanostructured TiC Layer is Highly Suitable Surface for Adhesion, Proliferation and Spreading of Cells

2020 ◽  
Vol 5 (2) ◽  
pp. 29 ◽  
Author(s):  
Mariangela Lopreiato ◽  
Alessia Mariano ◽  
Rossana Cocchiola ◽  
Giovanni Longo ◽  
Pietro Dalla Vedova ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
Titanium Carbide ◽  
Collagen Type ◽  
Collagen Type I ◽  
Bone Morphogenetic Protein 2 ◽  
Type I ◽  
Good Adhesion ◽  
Functional Coating ◽  
Adhesion Properties ◽  
Coated Glass

Cell culture is usually performed in 2D polymer surfaces; however, several studies are conducted with the aim to screen functional coating molecules to find substrates more suitable for cell adhesion and proliferation. The aim of this manuscript is to compare the cell adhesion and cytoskeleton organization of different cell types on different surfaces. Human primary fibroblasts, chondrocytes and osteoblasts isolated from patients undergoing surgery were seeded on polystyrene, poly-d-lysine-coated glass and titanium carbide slides and left to grow for several days. Then their cytoskeleton was analyzed, both by staining cells with phalloidin, which highlights actin fibers, and using Atomic Force Microscopy. We also monitored the production of Fibroblast Growth Factor-2, Bone Morphogenetic Protein-2 and Osteocalcin, using ELISA, and we highlighted production of Collagen type I in fibroblasts and osteoblasts and Collagen type II in chondrocytes by immunofluorescences. Fibroblasts, chondrocytes and osteoblasts showed both an improved proliferative activity and a good adhesion ability when cultured on titanium carbide slides, compared to polystyrene and poly-d-lysine-coated glass. In conclusion, we propose titanium carbide as a suitable surface to cultivate cells such as fibroblasts, chondrocytes and osteoblasts, allowing the preservation of their differentiated state and good adhesion properties.

The expression of two collagen receptor subfamilies, integrins and discoidin domains during osteogenic and chondrogenic differentiation of human mesenehymal stem cells

2021 ◽  
pp. 1-11
Author(s):  
Fan Xue ◽  
Wei Zhou ◽  
Zedong Lan
Keyword(s):  
Stem Cells ◽  
Chondrogenic Differentiation ◽  
Collagen Type ◽  
Collagen Type I ◽  
Type I ◽  
Integrin Subunit ◽  
Western Blots ◽  
Qrt Pcr ◽  
Collagen Receptors ◽  
Collagen Receptor

BACKGROUND: Collagen receptors are characterized by binding to and being activated by collagens. We know little about the molecular mechanism by which the integrins and discoidin domains (DDRs) recognize collagen. OBJECTIVE: The aim of this study was to investigate the expression of two main collagen receptor subfamilies, integrins and DDRs, during osteogenic and chondrogenic differentiation of human mesenehymal stem cells (hMSCs). METHODS: Using qRT-PCR, Western blots and FACS, the levels of DDR1, DDR2, integrin subunits β1, α1, α2, α10 and α11 receptors on hMSCs, were assessed upon activation by collagen type I, as well as during osteogenic and chondrogenic differentiation. RESULTS: The expression of DDR2 and integrin α11β1 was altered compared with other receptors when the cells were cultured under undifferentiated conditions. During osteogenic and chondrogenetic differentiation, DDR2 and α11 were up-regulated during early stages (6 day) of osteogenesis and chondrogenesis, respectively. The expression and activation of DDR2 was concomitant with another receptor integrin subunit β1 during osteogenetic differentiation. CONCLUSIONS: The results suggested that DDR2 was more specific for osteogenesis than chondrogenesis, while integrin α11β1 was more specific in chondrogenesis. DDR2 and α11 may play a role in the regulation of osteogenesis and chondrogenesis based on the differential expression of these receptors during lineage-dependent changes.

scholarly journals Interactions of the neural cell adhesion molecule and the myelin-associated glycoprotein with collagen type I: involvement in fibrillogenesis.

1992 ◽  
Vol 116 (4) ◽  
pp. 1063-1070 ◽  
Author(s):  
R Probstmeier ◽  
T Fahrig ◽  
E Spiess ◽  
M Schachner
Keyword(s):  
Extracellular Matrix ◽  
Cell Adhesion ◽  
Adhesion Molecules ◽  
Cell Adhesion Molecule ◽  
Neural Cell Adhesion Molecule ◽  
Collagen Type ◽  
Collagen Type I ◽  
Type I ◽  
Neural Cell Adhesion ◽  
Myelin Associated Glycoprotein

To gain insights into the functional role of the molecular association between neural adhesion molecules and extracellular matrix constituents, soluble forms of the myelin-associated glycoprotein (MAG) and the neural cell adhesion molecule (N-CAM), representing most of the extracellular domains of the molecules, were investigated in their ability to modify fibrillogenesis of collagen type I. MAG and N-CAM retarded the rate of fibril formation, as measured by changes in turbidity, and increased the diameter of the fibrils formed, but did not change the banding pattern when compared to collagen type I in the absence of adhesion molecules. Scatchard plot analysis of the binding of MAG and N-CAM to the fibril-forming collagen types I, II, III, and V suggest one binding site for N-CAM and two binding sites for MAG. Binding of MAG, but not of N-CAM, to collagen type I was decreased during fibril formation, probably due to a reduced accessibility of one binding site for MAG during fibrillogenesis. These results indicate that the neural adhesion molecules can influence the configuration of extracellular matrix constituents, thus, implicating them in the modulation of cell-substrate interactions.

Sign in / Sign up

Export Citation Format

Share Document