Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001511 (Adhesion)
 5,955 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A baculovirus system was used to express full-length recombinant mouse thrombospondin 2 (rTSP2) as a disulfide-bonded homotrimer with an NH2 terminus beginning with Asp20.rTSP2, like TSP1, was more sensitive to trypsin digestion if depleted of calcium ion. The trypsin digestion pattern of rTSP2 and TSP1 differed in that trypsin cut between the first and second type 1 modules of rTSP2. For bovine aortic endothelial cells adhering to TSP-coated polystyrene plates, reduction after coating caused both TSPs to be much more adhesive; these adhesions were blocked completely by RGDS peptide or antibody to alpha v beta 3 integrin.rTSP2 and TSP1 also mediated the adhesion of HT-29 human colon adenocarcinoma cells that carry alpha v beta 5 but not alpha v beta 3 integrin. Antibody to alpha v beta 5 did not inhibit adhesion of HT-29 cells to TSP1 or rTSP2. Rather, adhesion of HT-29 cells was decreased by treatment of TSPs with EDTA, abolished by reduction of the TSPs, and, in the case of rTSP2, blocked by heparin. Adhesion of MG63 cells to both TSPs was complex. Treatment with EDTA enhanced the adhesive activity of rTSP2 but decreased the adhesive activity of TSP1. These results show that TSP2 can be processed and secreted when overexpressed using baculovirus, TSP1 and rTSP2 differ in protease susceptibility in the type 1 module region, and TSP1 and rTSP2 mediate cell adhesion by complex and similar but not identical mechanisms.
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PMID:Properties of recombinant mouse thrombospondin 2 expressed in Spodoptera cells. 779 22

Cell adhesion to thrombospondin-1 (TSP-1) correlates with assembly of cell-substratum contact structures that contain fascin microspikes. In this analysis, cell-matrix requirements for assembly of fascin microspikes were examined in detail. In six cell lines, cell spreading on a TSP-1 substratum correlated with expression of fascin protein and formation of fascin microspikes. Microspikes were not formed by H9c2 cells adherent on fibronectin, vitronectin, collagen IV, or platelet factor 4. However, both fascin microspikes and focal contacts were assembled by cells adherent on laminin-1. Using mixed substrata containing different proportions of TSP-1, and fibronectin, fascin microspike formation by H9c2 and C2C12 cells was found to be reduced on substrata containing 25% fibronectin and abolished on substrata containing 75% fibronectin. Adhesion to intermediate mixtures of TSP-1 and fibronectin resulted in coassembly of fascin microspikes and focal contacts, colocalization of fascin with actin stress fiber bundles and altered distributions of beta 1 integrins, cortical alpha-actinin, and tropomyosin. In cells adherent on 50% TSP-1:50% fibronectin, GRGDSP peptide treatment decreased focal contact assembly and altered cytoskeletal organization but did not inhibit microspike assembly. Treatment with chondroitin sulfate A or p-nitrophenol beta-D-xylopyranoside decreased microspike formation and modified cytoskeletal organization but did not inhibit focal contact formation. In polarized migratory and postmitotic C2C12 cells, fascin microspikes and ruffles were localized at leading edges and TSP matrix deposition was also concentrated in this region. Depletion of matrix TSP by heparin treatment correlated with decreased microspike formation and cell motility. Thus, the balance of adhesive receptors ligated at the cell surface during initial cell-matrix attachment serves to regulate the type of substratum adhesion contact assembled and subsequent cytoskeletal organization. A role for fascin microspikes in cell motile behavior is indicated.
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PMID:Characterization of cell-matrix adhesion requirements for the formation of fascin microspikes. 936 73

Transforming growth factor beta1 (TGF-beta1) is a secreted polypeptide that is thought to play a major role in the regulation of folliculogenesis and differentiation of thyroid cells. On porcine thyroid follicular cells cultured on plastic substratum, TGF-beta1, in a concentration-dependent way, promoted the disruption of follicles, cell spreading, migration and confluency by a mechanism that did not involve cell proliferation. TGF-beta1 strongly activated the production of thrombospondin-1 and (alpha)vbeta3 integrin in a concentration-dependent manner whereas the expression of thyroglobulin was unaffected. Anisomycin, an inhibitor of protein synthesis, inhibited the effect of TGF-beta1 on cell organization. Thrombospondin-1 reproduced the effect of TGF-beta1. In the presence of thrombospondin-1 cells did not organize in follicle-like structures but, in contrast, spreaded and reached confluency independently of cell proliferation. This effect is suppressed by an RGD-containing peptide. The adhesive properties of thrombospondin-1 for thyroid cells were shown to be mediated by both the amino-terminal heparin-binding domain and the RGD domain of thrombospondin-1. Adhesion was shown to involve (alpha)vbeta3 integrin. The results show that TGF-beta1 exerted an influence upon function and behaviour of follicle cells partly mediated by the synthesis of thrombospondin-1 and of its receptor (alpha)vbeta3 integrin.
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PMID:Influence of transforming growth factor beta1 (TGF-beta1) on the behaviour of porcine thyroid epithelial cells in primary culture through thrombospondin-1 synthesis. 1019 19

Lymphocyte adhesion to cells and extracellular matrix (ECM) via integrins plays a pivotal role for the function of the immune system. We show here that endogenous thrombospondin-1 (TSP-1) is a cell-surface ligand for cis interaction of surface receptors in T lymphocytes controlled by integrins and the T-cell antigen receptor (TCR/CD3). Stimulation of CD3 triggers rapid surface expression of TSP-1 in quiescent T cells, whereas activated cells express TSP-1 constitutively. Endogenous TSP-1 is attached to lipoprotein receptor-related protein 1 (LRP1/CD91) and calreticulin (CRT) on the cell surface through its NH2-terminal domain. Adhesion via integrins to ICAM-1 or ECM components up-regulates TSP turnover dramatically from a low level in nonadherent cells, whereas CD3 stimulation inhibits TSP turnover through interference with CD91/CRT-mediated internalization. Integrin-associated protein (IAP/CD47) is essential for TSP turnover and adhesion through interaction with the C-terminal domain of TSP-1 in response to triggering signals delivered at the NH2-terminal. These results indicate that endogenous TSP-1 connects separate cell-surface receptors functionally and regulates T-cell adhesion.
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PMID:Endogenous thrombospondin-1 is a cell-surface ligand for regulation of integrin-dependent T-lymphocyte adhesion. 1683 79