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

This study surveyed some adhesive properties of strains of Fusobacterium nucleatum representative of the 3 recently defined groups or subspecies that could relate to their colonization and virulence. With one exception, F. nucleatum strains agglutinated sheep erythrocytes, but the quantity of bacteria required and the sensitivity of the hemagglutination reactions to inhibition by 0.05 M galactose or arginine varied between strains, and did not exhibit clear-cut correlations with subspecies. Neuraminidase treatment of erythrocytes generally enhanced the hemagglutinating activity of most strains, but trypsin treatment had no effect. Strains of F. nucleatum also attached in moderate numbers to buccal epithelial cells. Treatment of the epithelial cells with neuraminidase or with trypsin increased the numbers of all Fusobacterium strains that attached. Treatment of hydroxyapatite (HA) beads with submandibular or parotid saliva also promoted the adhesion of all strains of F. nucleatum studied. Treatment of HA with human serum or albumin produced a selective effect. Adhesion of some strains was promoted by serum and albumin treatment, and that of other strains was unaffected. Adhesion of all strains of F. nucleatum was enhanced to statherin-treated HA, whereas HA treated with salivary proline-rich protein-1 did not foster F. nucleatum attachment. Three of 4 strains of the subspecies vincentii, and each of 2 polymorphum strains studied exhibited strong adhesion to HA treated with either human type I or type IV collagen. However, only 1 of 5 strains of the subspecies nucleatum bound well to collagen-treated HA.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Adhesive properties of strains of Fusobacterium nucleatum of the subspecies nucleatum, vincentii and polymorphum. 182 May 61

Adhesion proteins are cofactors in the aggregation of human platelets, and can mediate the ADP-induced response of these cells. It was shown that the synthetic cell adhesion peptide, Arg-Gly-Asp-Ser inhibits the aggregation of platelets from normal donors and ophthalmic patients with diabetic retinopathy, glaucoma and retinal vein occlusion. This effect increases in the relative order of activity retinal vein occlusion greater than or equal to glaucoma greater than or equal to diabetic retinopathy greater than control. Deaggregation due to the peptide appeared to be diminished in the order control (normal) greater than diabetic retinopathy greater than glaucoma greater than retinal vein occlusion after its addition at the maximum of aggregation curve. It is concluded that there are differences in the ability of Arg-Gly-Asp-Ser peptide to block the fibronectin adhesion receptor on ADP stimulated platelets from different clinical groups.
 ...
PMID:Modulative effects of cell adhesion peptide (Arg-Gly-Asp-Ser) on the aggregation of stimulated platelets from ophthalmic patients. 182 18

Altered T cell adherence after human immunodeficiency virus 1 (HIV-1) infection may contribute to viral pathogenesis in the acquired immune deficiency syndrome. To address this hypothesis, we assessed mechanisms of T cell adherence to extracellular matrix proteins in vitro. We found that after HIV-1 infection, both chronically infected H9 CD4+ T cells and acutely infected primary peripheral blood lymphocytes acquired the ability to adhere to the extracellular matrix glycoprotein fibronectin, to a lesser extent to type IV collagen and laminin, but not to type I collagen. H9 cells chronically infected with two of the three HIV-1 strains studied showed approximately a sevenfold increase in attachment to fibronectin, while the same cells infected with the human retrovirus HIV-2 did not. Adhesion was accompanied by changes in morphology, including marked spreading and increased filopodia. These alterations were not blocked by the protein kinase C inhibitor H-7, which did inhibit TPA-induced T cell attachment to fibronectin. Monoclonal antibodies against both the alpha 5 and the beta 1 subunits of the classical fibronectin receptor as well as an Arg-Gly-Asp (RGD) peptide inhibited attachment, whereas anti-alpha 4 monoclonal antibodies and the CS1 peptide did not. Binding to collagen IV was also inhibited by the anti-beta 1 monoclonal antibody, but not the other antibodies. Cells metabolically labeled with [35S]methionine and analyzed by immunoprecipitation with polyclonal anti-beta 1 integrin antibody showed a 2.5-fold increase in integrin synthesis in infected cells compared to uninfected controls. This increase in synthesis was associated with an increase in cell surface expression of both alpha 5 and beta 1 integrins by FACS (registered trademark of Becton Dickinson for a fluorescence-activated cell sorter) analysis. Enhanced expression of integrins such as alpha 5 beta 1 may cause T cell adherence to a variety of tissues, where released viral gene products may induce some of the tissue-specific manifestations of HIV-1 infection.
 ...
PMID:HIV-1 infection of human T lymphocytes results in enhanced alpha 5 beta 1 integrin expression. 183 Dec 4

Adhesion between lymphocytes and antigen-presenting cells is necessary for the development of certain immune reactions. We have previously shown that fibronectin (FN) added to mixed lymphocyte cultures (MLC) can restore a decreased lymphocyte proliferation in immunocompromised individuals. Using highly purified cell populations from peripheral blood for depletion and adding back experiments we show here that exogenous FN enhanced proliferation only when allogeneic monocytes were co-cultured with responder lymphocytes. Although lymphocyte proliferation in MLC was augmented by FN, there was no preferential proliferation of any particular major lymphocyte subpopulation in cultures supplemented with FN as compared to control cultures lacking its addition. Antibody against the FN receptor (FN-R) of the beta 1 integrin family, as well as Arg-Gly-Asp containing peptide, could inhibit alloantigen-induced lymphocyte proliferation in a concentration-dependent manner. Anti-CD3-induced proliferation was inhibited by anti-FN-R antibody but not Arg-Gly-Asp peptide whereas no inhibition was seen with the phytohemagglutinin (PHA)-induced lymphocyte proliferation. This study presents further evidence that FN and its receptor (alpha 5 beta 1) are involved in the augmentation of T-cell responsiveness to proliferative stimuli.
 ...
PMID:Involvement of fibronectin and its receptor in human lymphocyte proliferation. 183 19

Unstimulated human platelets from normal volunteers adhere to sulfatides (galactosylceramide-I3-sulfate) as single cells but do not adhere appreciably to other lipids including gangliosides, neutral glycolipids, phospholipids or cholesterol-3-SO4. Platelet adhesion to sulfatide is saturable and dose-dependent, reaches maximal levels in 90 to 120 min, and is not divalent cation-dependent. Because sulfatides bind von Willebrand factor (vWf) with specificity and high affinity and platelet adhesion to structurally related sulfated glycolipids is approximately proportionate to their ability to bind vWf, we examined whether vWf mediates platelet adhesion to sulfatides. Platelets from a patient with severe Type I von Willebrand's disease adhere poorly to sulfatides. However, adhesion to levels seen with normal platelets is restored by the addition of vWf. Adhesion of normal platelets can be partially inhibited by a monospecific antibody to vWf. Normal platelet adhesion to sulfatides, however, is not increased following preincubation with vWf. Both vWf binding and platelet adhesion to sulfatides can be inhibited by the sulfated polysaccharide dextran sulfate at low concentration, fucoidan at high concentrations, but not by heparin, fibrinogen, fibronectin, or the synthetic peptides Gly-Arg-Gly-Asp-Ser-Pro or Gly-Arg-Gly-Glu-Ser-Pro. Thus, adhesion to sulfatides appears to be of two types; vWf dependent (50-75%) and vWf independent (25-50%).
 ...
PMID:Platelets adhere to sulfatides by von Willebrand factor dependent and independent mechanisms. 187 20

A 22 x 10(3) Mr protein (abbreviated 22K) that copurifies with dermatan sulfate proteoglycans (DS-PGs) following the biochemical fractionation of bovine fetal skin has been evaluated for adhesion-promoting activity in vitro using Balb/c 3T3 cells, as well as bovine and human dermal fibroblasts. Substrata coated with 22K protein promote attachment of a subset of 3T3 and dermal fibroblasts that respond to plasma fibronectin (pFN) substrata. Cells on 22K protein display partial cytoplasmic spreading, comparable to that of cells adhering to cell-binding fragments of pFN. Adhesion activity of 22K is not due to contamination with known adhesive proteins of dermal matrices and is not dermal cell type-specific, since two classes of neuronal cells also respond effectively to 22K substrata. DS-PGs from cartilage or skin completely inhibit 22K adhesion activity when the PGs are adsorbed to 22K substrata under conditions prohibiting PGs from binding to substrata directly. Cartilage chondroitin/keratan sulfate proteoglycan at much higher concentrations is only partially inhibitory. Inhibition by DS-PGs is mediated by DS chains binding to 22K. Properties of the cell surface 'receptor' for 22K protein were tested by several approaches. It is not cell surface DS-PG, since: (1) cells unable to produce this proteoglycan class also responded; (2) cells treated with chondroitinase ABC responded equally well; and (3) substrata of proteoglycan-binding platelet factor-4 generated responses from cells that were quantitatively and qualitatively different. A synthetic peptide in the medium containing the Arg-Gly-Asp-Ser (RGDS) sequence completely inhibited responses to 22K substrata. This observation, coupled with sequencing data of 22K protein revealing an Arg-Gly-Ala-Thr sequence at residues 151-154, suggest that 22K protein mediates adhesion by cell surface integrin binding. Therefore, this newly discovered matrix protein from skin may serve as a communication link between the dermal fibroblast cell surface and its extracellular matrix environment.
 ...
PMID:Extracellular matrix adhesion-promoting activities of a dermatan sulfate proteoglycan-associated protein (22K) from bovine fetal skin. 193 76

Small cell lung cancer (SCLC) is a fatal malignancy due to its propensity to metastasize widely and to reoccur after chemotherapy in a drug-resistant form. While most SCLC cell lines are anchorage independent for growth, laminin induced the attachment of five of six SCLC cell lines tested (NCI-N417, NCI-H345, NCI-H146, NCI-H187, NCI-H510, and NCI-H209). NCI-N417 SCLC cells adopted a flattened morphology on laminin, and a classic SCLC cell line (NCI-H345) demonstrated a neuron-like appearance while the other SCLC cell lines except NCI-H187 cells, attached but did not spread. Adhesion to laminin was associated with increased resistance to several cytotoxic drugs. Matrigel, an extract of basement membrane proteins, greatly accelerated tumor growth when coinjected with SCLC cells in athymic mice. A synthetic peptide from the B1 chain of laminin, cyclic-YIGSR (Tyr-Ile-Gly-Ser-Arg), inhibited laminin-induced SCLC cell adhesion and migration in vitro and reduced the size of the tumors they formed when coinjected with matrigel and YIGSR. These results suggest that the interaction of SCLC cells with laminin and possibly with other basement membrane proteins can enhance their tumorigenicity and drug resistance.
 ...
PMID:Reconstituted basement membrane (matrigel) and laminin can enhance the tumorigenicity and the drug resistance of small cell lung cancer cell lines. 216 54

Human umbilical vein endothelial cells (ECs) adhere in vitro to proteins of the extracellular matrix including fibronectin (fn) and vitronectin (vn). Specific receptors for fn and vn have been previously characterized. These receptors belong to a family of membrane glycoproteins characterized (a) by being a transmembrane complex of two noncovalently linked subunits and (b) by recognizing the tripeptide Arg-Gly-Asp on their respective ligands. In this paper we investigated how vn and fn control the organization of their respective receptors over the surface of ECs. It was found that the clustering of individual receptors and the organization thereafter of focal contacts occurred only when ECs were exposed to the specific ligand and did not occur on the opposite ligand. The shape of receptor clusters was slightly different and a colocalization of the two receptors was found when ECs were cultured on a mixed matrix of fn plus vn. Adhesion was selectively inhibited by vn or fn receptor antibodies on their respective substrates. The clustering of both receptors preceded the association of vinculin with focal contacts and stress fiber formation. Also, the vn receptor, in the absence of associated fn receptor, was capable of inducing the organization of the membrane-microfilament interaction complex. Overall, these results indicate that individual matrix ligands induce only the clustering of their respective membrane receptors. The clustering of only one receptor is capable of supporting the subsequent formation of focal contacts and the local assembly of related cytoskeletal proteins.
 ...
PMID:Fibronectin and vitronectin regulate the organization of their respective Arg-Gly-Asp adhesion receptors in cultured human endothelial cells. 245 62

We have prepared protein-peptide conjugates composed of bovine serum albumin (BSA) derivatized with short peptides containing the Arg-Gly-Asp (RGD) sequence derived from the adhesion site of fibronectin. The RGD-BSA conjugates were used to coat tissue culture plastic surfaces which then served as substrata in cell adhesion experiments. Our results indicate that the efficiency of adhesion to RGD-BSA-coated surfaces is highly dependent on the valency of the (RGD)n-BSA conjugates. For example, on surfaces with approximately equal amounts of RGD ligand, CHO cells adhered virtually 100% to the (RGD)n-BSA (n = 20.8) conjugate and not at all to the (RGD)n-BSA (n = 3.5) conjugate. Adhesion on (RGD)n-BSA-coated substrata and on fibronectin- or vitronectin-coated substrata was also examined in terms of the relationship between cell adhesion and the intermolecular distances of adsorbed proteins. It was observed that for substrata coated with relatively compact, symmetric molecules, such as RGD-BSA or vitronectin, adhesion dropped off sharply as intermolecular distances increased; by contrast, for fibronectin, a large asymmetric molecule, adhesion declined more gradually as intermolecular distances increased. Finally, we have examined the role of different cell-surface receptors in the process of adhesion to RGD-BSA substrata. Interestingly, competition and blocking experiments with antibodies and with soluble competing proteins suggest that it is the vitronectin receptor rather than the fibronectin receptor which mediates adhesion to RGD-BSA.
 ...
PMID:(Arg-Gly-Asp)n-albumin conjugates as a model substratum for integrin-mediated cell adhesion. 246 96

Microvascular endothelial cells (MEC) must use a set of surface receptors to adhere not only to the vascular basement membrane but, during angiogenic stimulation, to the interstitium. We examined how cultured MEC isolated from human foreskin interact with their subendothelial matrix. MEC were able to attach to diverse extracellular matrix proteins, including fibronectin (Fn), vitronectin (Vn), laminin (Ln), type I and IV collagen, as well as to fibrinogen and gelatin. Adhesion to Fn, but not to laminin or collagens, was specifically blocked in the presence of Arg-Gly-Asp (RGD)-containing peptides. When surface radioiodinated MEC were solubilized and subjected to affinity chromatography on Fn-Sepharose columns, two polypeptides of 150 and 125 kD, corresponding to the integrin heterodimer alpha 5 beta 1, were identified. MEC also express a complex of 150 (alpha) and 95 kD (beta 3) that is related to the Vn receptor. Immunofluorescent staining of MEC cultures with antibodies to the integrin beta 1 subunit demonstrated receptors on the basolateral surface at focal adhesion plaques that co-localized with vinculin and with Fn-positive matrix fibers. Occasionally, antibodies to the Vn receptor stained the vinculin-positive focal adhesion plaques that frequently co-localized with the beta 1 complex. However, in cultures of MEC that were attached to substrates coated with alternating strips of Fn and Vn, the beta 1 complex was preferentially localized to the Fn substrate, while the Vn receptor was concentrated on the Vn substrate. The results indicate that MEC express at least two different heterodimer adhesion receptors that belong to the integrin super-family and appear to have distinct ligand specificities: the Fn receptor and the Vn receptor. These receptors mediate cell adhesion to the extracellular matrix and presumably have an important role in hemostasis and neovascularization.
 ...
PMID:Human microvascular endothelial cells express integrin-related complexes that mediate adhesion to the extracellular matrix. 246 86


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>