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Query: UMLS:C0001511 (Adhesion)
 5,955 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Interaction between neutrophils and platelets at the site of vascular damage or in ischaemic tissue may promote thrombosis and/or vascular occlusion. To study this interaction, we have developed a novel technique that allows visualization of adhesion of flowing neutrophils to immobilized, activated platelets. The total number of adherent neutrophils decreased with increasing wall shear stress in the range 0.05 to 0.4 Pa. Although a proportion of the adherent neutrophils were stationary, most were rolling with a velocity greater than 0.4 micron/s. The percentage of rolling cells increased with increasing wall shear stress, but the mean rolling cell velocity was nearly independent of shear stress. Adhesion of neutrophils was nearly abolished by treatment of the platelets with antibody to P-selectin, or by treatment of neutrophils with either neuraminidase, dextran sulfate, or EDTA. Studies with a series of antibodies to L-selectin (TQ-1, Dreg-56, LAM1-3, and LAM1-10) suggested that this molecule was one neutrophil ligand for rolling adhesion. Thus, sialylated carbohydrate on neutrophils appears essential for P-selectin-mediated adhesion, and a proportion of this ligand may be presented by L-selectin. Treatment of the neutrophils with N-formyl-methionyl-leucyl-phenylalanine decreased the number of rolling cells, and increased the rolling velocity, possibly due to shedding of neutrophil ligand(s) and/or cell shape change. In vivo, immobilized platelets could play an important role in promoting attachment of neutrophils to vessel walls, eg, by slowing neutrophils so that integrin-mediated immobilization could occur.
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PMID:Selectin-mediated rolling of neutrophils on immobilized platelets. 768 89

The neural cell adhesion molecule (NCAM) is thought to have an important role in cell-cell interactions during development. To better understand NCAM function, we studied the adhesion of mouse N2A neuroblastoma cells and Chinese hamster ovary cells to different forms of NCAM using a quantitative centrifugal cell adhesion assay that measures the rate of cell removal from experimental substrates. Embryonic brain NCAM is highly polysialylated and contains both 180- and 140-kDa polypeptide isoforms, whereas embryonic retinal NCAM is less highly polysialylated and contains primarily the 140-kDa isoform. For both forms, cell adhesion to substrate-immobilized NCAM was temperature dependent, cation independent, and time dependent. Cell adhesion to NCAM substrates was not directly affected by drugs inhibiting cytoskeletal function or cellular metabolism, suggesting that NCAM function does not depend critically on cytoskeletal function or metabolic activity. Cell adhesion to retinal NCAM was blocked by anti-NCAM antibodies, and adhesion was increased by neuraminidase treatment of both types of NCAM. Adhesion to brain NCAM was effectively blocked by anti-NCAM antibodies only after neuraminidase treatment, suggesting that these cells adhere to highly sialylated and less-sialylated NCAM by different mechanisms. We propose that multiple mechanisms of cell adhesion involving NCAM may exist in different tissues during development and that the state of polysialylation of NCAM is important in regulating the relative importance of these mechanisms.
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PMID:Multiple mechanisms of N2A and CHO cell adhesion to NCAM purified from chick embryonic brain and retina. 808 14

S fimbriae purified from recombinant Escherichia coli HB101(pANN801-13) bound strongly to extracellular matrices of cultured endothelial and epithelial cells; only poor binding was seen with the fimbriae purified from the sfaS mutant strain HB101(pANN801-1321). E. coli HB101(pANN801-13) adhered strongly to laminin immobilized on glass; no adhesion was seen to type I, III, IV, or V collagen. Strain HB101(pANN801-1321) failed to adhere to any of the target proteins. Adhesion to laminin of strain HB101(pANN801-13) was inhibited by sialyl-alpha-2,3-lactose as well as by periodate oxidation and neuraminidase treatment of laminin. In Western blotting, the purified S fimbriae recognized more strongly the A chain than the B chains of laminin.
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PMID:Sialyloligosaccharide chains of laminin as an extracellular matrix target for S fimbriae of Escherichia coli. 810 97

Nerve cells depend on specific interactions with glial cells for proper function. Myelinating glial cells are thought to associate with neuronal axons, in part, via the cell-surface adhesion protein, myelin-associated glycoprotein (MAG). MAG is also thought to be a major inhibitor of neurite outgrowth (axon regeneration) in the adult central nervous system. Primary structure and in vitro function place MAG in an immunoglobulin-related family of sialic acid-binding lactins. We report that a limited set of structurally related gangliosides, known to be expressed on myelinated neurons in vivo, are ligands for MAG. When major brain gangliosides were adsorbed as artificial membranes on plastic microwells, only GT1b and GD1a supported cell adhesion of MAG-transfected COS-1 cells. Furthermore, a quantitatively minor ganglioside expressed on cholinergic neurons, GQ1b alpha (also known as Chol-1 alpha-b), was much more potent than GT1b or GD1a in supporting MAG-mediated cell adhesion. Adhesion to either GT1b or GQ1b alpha was abolished by pretreatment of the adsorbed gangliosides with neuraminidase. On the basis of structure-function studies of 19 test glycosphingolipids, an alpha 2,3-N-acetylneuraminic acid residue on the terminal galactose of a gangliotetraose core is necessary for MAG binding, and additional sialic acid residues linked to the other neutral core saccharides [Gal(II) and GalNAc(III)] contribute significantly to binding affinity. MAG-mediated adhesion to gangliosides was blocked by pretreatment of the MAG-transfected COS-1 cells with anti-MAG monoclonal antibody 513, which is known to inhibit oligodendrocyte-neuron binding. These data are consistent with the conclusion that MAG-mediated cell-cell interactions involve MAG-ganglioside recognition and binding.
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PMID:Gangliosides are neuronal ligands for myelin-associated glycoprotein. 857 Jun 40

We tested the hypothesis that nonspecific repulsion, as a result of electrostatic forces and (or) steric stabilization effects, impaired adhesion more efficiently under dynamic than under static conditions. Cells from the human monocytic line THP1 were plated on a glass surface. Spherical particles bearing monoclonal antibodies specific for antigens expressed by THP1 cells (CD11b, CD18, CD35, CD64) were then added and adhesion was quantified. The effect of neuraminidase treatment of THP1 cells was also studied. Adhesion was then measured in a flow chamber under low shear flow (wall shear rate was 11 or 22 s-1), allowing a quantitative determination of cell adhesion frequency. The following conclusions were obtained: (i) under static conditions, neuraminidase treatment had little effect on adhesion (only CD18-mediated interaction was significantly increased at 4 degrees C after enzyme treatment); (ii) under dynamic conditions, neuraminidase treatment significantly increased binding; (iii) surprisingly, there was no clear relationship between the length of adhesion molecules involved in the interaction and binding efficiency; and (iv) such parameters as cell shape and topographical distribution of adhesion molecules may strongly influence adhesion under flow. It is concluded that a dynamic reorganization of the pericellular matrix following intercellular contact may play an important role in regulating adhesion.
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PMID:Influence of surface charges on cell adhesion: difference between static and dynamic conditions. 870 13

Ligands on human basophils for the endothelial adhesion molecules intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), mucosal addressin cell adhesion molecule-1 (MAdCAM-1), and E-selectin were investigated. Adhesion of basophils to endothelial cells was inhibited by mAb recognizing CD18, CD11a, and/or CD11b, with the pattern and magnitude of inhibition dependent upon the activation state of the basophils and endothelium. Adhesion to recombinant VCAM-1 was completely inhibited by mAb recognizing alpha 4 integrin and partially by mAb to the beta 1 or beta 7 subunit; surface expression of these integrins was also detected. Adhesion to recombinant MAdCAM-1 expressed on Chinese hamster ovary cells was completely inhibited by mAb recognizing alpha 4 and/or beta 7 integrins. Adhesion to recombinant E-selectin was completely inhibited by basophil pretreatment with neuraminidase and partially inhibited by endo-beta-galactosidase. By flow cytometry, bimodal patterns of expression of sialyl-Lewis X- and sialyl-dimeric-Lewis X were observed, and adherent cells tended to be sialyl-dimeric-Lewis X positive. Thus, basophils express beta 1, beta 2, and beta 7 integrins along with sialylated surface ligands that may interact with the endothelium during basophil recruitment responses.
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PMID:Counter-receptors on human basophils for endothelial cell adhesion molecules. 875 37

Adhesion of microcrystals to the apical surface of renal tubular cells could be a critical step in the formation of kidney stones. The role of membrane surface charge as a determinant of the interaction between renal epithelial cells (BSC-1 line) and the most common crystal in kidney stones, calcium oxalate monohydrate (COM), was studied in a tissue culture model system. Adhesion of COM crystals to cells was blocked by cationized ferritin. Other cations that bind to cells including cetylpyridinium chloride and polylysine, as well as cationic dyes such as Alcian blue, also inhibited adhesion of COM crystals, but not all polycations shared this effect. Specific lectins including Triticum vulgaris (wheat germ agglutinin) blocked crystal binding to the cells. Furthermore, treatment of cells with neuraminidase inhibited binding of crystals. Therefore, anionic cell surface sialic acid residues appear to function as COM crystal receptors that can be blocked by specific cations or lectins. In vivo, alterations in the structure, function, quantity, or availability of these anionic cell surface molecules could lead to crystal retention and formation of renal calculi.
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PMID:Adhesion of calcium oxalate monohydrate crystals to anionic sites on the surface of renal epithelial cells. 876 39

Adhesion of microcrystals that nucleate in tubular fluid to the apical surface of renal tubular cells could be a critical step in the formation of kidney stones, 20% of which contain hydroxyapatite (HA). HA crystals bound rapidly to monolayer cultures of monkey kidney epithelial cells (BSC-1 line), used to model the surface of the nephron, in a concentration-dependent manner. Adhesion was blocked by diverse polyanions including heparin, pentosan polysulfate, polyaspartate, and polyglutamate, as well as many found in tubular fluid such as chondroitin sulfates A and B, heparan sulfate, citrate, nephrocalcin, and osteopontin. The polycations cetylpyridinium chloride and cationized ferritin, as well as the cationic dyes alcian blue, polyethylenimine, and brilliant blue R, also inhibited adhesion of HA crystals, as did specific lectins including Triticum vulgaris (wheat germ agglutinin). Anions that inhibited adhesion of crystals appeared to act on the crystal surface, whereas cations and lectins exerted their effect on the cell. Treatment of cells with neuraminidase inhibited binding of crystals, suggesting that anionic cell surface sialic acid residues function as HA crystal receptor sites that can be blocked by specific cations or lectins. Adherence of HA crystals to cells of another renal line (MDCK) and, to 3T3 fibroblasts was also inhibited by heparin, polyaspartate, alcian blue, and T vulgaris lectin, suggesting that these crystals bind to analogous molecules on the surface of different types of cells. These results suggests that the structure, quantity, and/or function of soluble anions in tubular fluid, as well as those anchored to the cell surface, could be critical determinants of HA crystal retention in the nephron and the subsequent formation of a renal stone.
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PMID:Adhesion of hydroxyapatite crystals to anionic sites on the surface of renal epithelial cells. 927 83

Sialic acids from sialoglycoconjugates present at the cell surface of Cryptococcus neoformans yeast forms were analyzed by high-performance thin-layer chromatography, binding of influenza A and C virus strains, enzymatic treatment, and flow cytofluorimetry with fluorescein isothiocyanate-labeled lectins. C. neoformans yeast forms grown in a chemically defined medium contain N-acetylneuraminic acid and its 9-O-acetylated derivative. A density of 3 x 10(6) residues of sialic acid per cell was found in C. neoformans. Sialic acids in cryptococcal cells are glycosidically linked to galactopyranosyl units as inferred from the increased reactivity of neuraminidase-treated yeasts with peanut agglutinin. N-Acetylneuraminic acids are alpha-2,6 and alpha-2,3 linked, as indicated by using virus strains M1/5 and M1/5 HS8, respectively, as agglutination probes. The alpha-2,6 linkage markedly predominated. These findings were essentially confirmed by the interaction of cryptococcal cells with the lectins Sambucus nigra agglutinin and Maackia amurensis agglutinin. We also investigated whether the sialyl residues present in C. neoformans are involved in the fungal interaction with a cationic solid-phase substrate and with mouse resident macrophages. Adhesion of yeast cells to poly-L-lysine was mediated, in part, by sialic acid residues, since the number of adherent cells was markedly reduced after treatment with bacterial neuraminidase. The enzymatic removal of sialic acids also made C. neoformans yeast cells more susceptible to endocytosis by macrophages. The results show that sialic acids are components of the cryptococcal cell surface that contribute to its negative charge and protect yeast forms against phagocytosis.
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PMID:Identification of N-acetylneuraminic acid and its 9-O-acetylated derivative on the cell surface of Cryptococcus neoformans: influence on fungal phagocytosis. 939 79

Recent reports have shown that leukocyte-leukocyte adhesion is dependent on L-selectin and that leukocyte recognition of L-selectin may be mediated by P-selectin glycoprotein ligand-1 (PSGL-1). We show that the specific attachment and rolling of human neutrophils and the leukemia cell lines HL-60 and U937 on immobilized, purified L-selectin under continuous shear stress is only partially inhibited by treatment with the PSGL-1 monoclonal antibody (MoAb), KPL1 (41% to 53% inhibition), suggesting that L-selectin ligand activity in addition to PSGL-1 may mediate myeloid cell rolling on L-selectin. K562 cells cotransfected with cDNAs encoding alpha (1,3)fucosyltransferase-VII (FucT-VII) and PSGL-1 rolled on L-selectin. Adhesion of FucT-VII-PSGL-1 transfectants to L-selectin was completely blocked by MoAb KPL1, indicating that both L-selectin and P-selectin bind similar sites on PSGL-1. In support of existence of a non-PSGL-1 L-selectin ligand activity on leukocytes, an HL-60 membrane preparation immunodepleted of PSGL-1 supported rolling of L-selectin, but not P-selectin transfectants. Treatment of HL-60 cells with O-sialoglycoprotein endopeptidase inhibited attachment and rolling on L-selectin and P-selectin. However, neuraminidase treatment completely blocked HL-60 rolling on L-selectin, but not P-selectin, suggesting L-selectin and P-selectin ligand activities have different contributions of sialic acid. These findings indicate that myeloid cells express sialylated, O-linked glycoprotein ligand activity independent of PSGL-1 that supports L-selectin-mediated rolling.
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PMID:Functional characterization of L-selectin ligands on human neutrophils and leukemia cell lines: evidence for mucinlike ligand activity distinct from P-selectin glycoprotein ligand-1. 944 70


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