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

Adhesion and inhibition experiments with pulmonary cells of BALB/c-mouse origin and syngeneic sarcoma L-1 cells indicated that L-fucose specific lectin-like adhesion molecules, presumably situated on pulmonary cell surfaces are (at least partly) responsible for the specificity of this cell-cell interaction. Addition of specific sugars and glycoconjugates (L-fucose and fucoidan, respectively) to the incubation medium evidently inhibited the adhesion process as quantified using radiolabelled tumor cells. Unspecific carbohydrates (e.g. D-galactose) did not affect the cellular interaction. In vivo, repeated administration of fucoidan (but not of unspecific glycoconjugates) significantly inhibited the settling of metastatic sarcoma L-1 cells in the lungs of BALB/c-mice. Therefore, when lectin-like adhesion molecules on pulmonary cells were blocked with competitive glycoconjugates, tumor cell colonization of the lung could be significantly inhibited.
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PMID:Blocking of lectin-like adhesion molecules on pulmonary cells inhibits lung sarcoma L-1 colonization in BALB/c-mice. 273 66

Cells of the rat neuronal line, PC12, adhere well to substrates coated with laminin and type IV collagen, but attach poorly to fibronectin. Adhesion and neurite extension in response to these extracellular matrix proteins are inhibited by Fab fragments of an antiserum (anti-ECMR) that recognizes PC12 cell surface integrin subunits of Mr 120,000, 140,000, and 180,000 (Tomaselli, K. J., C. H. Damsky, and L. F. Reichardt. 1987. J. Cell Biol. 105:2347-2358). Here we extend our study of integrin structure and function in PC12 cells using integrin subunit-specific antibodies prepared against synthetic peptides corresponding to the cytoplasmic domains of the human integrin beta 1 and the fibronectin receptor alpha (alpha FN) subunits. Anti-integrin beta 1 immunoprecipitated a 120-kD beta 1 subunit and two noncovalently associated integrin alpha subunits of 140 and 180 kD from detergent extracts of surface-labeled PC12 cells. Immunodepletion studies using anti-integrin beta 1 demonstrated that these two putative alpha/beta heterodimers are identical to those recognized by the adhesion-perturbing ECMR antiserum. Anti-alpha FN immunoprecipitated fibronectin receptor heterodimers in human and rat fibroblastic cells, but not in PC12 cells. Thus, low levels of expression of the integrin alpha FN subunit can explain the poor attachment of PC12 cells to FN. The PC12 cell integrins were purified using a combination of lectin and ECMR antibody affinity chromatography. The purified integrins: (a) completely neutralize the ability of the anti-ECMR serum to inhibit PC12 cell adhesion to laminin and collagen IV; (b) have hydrodynamic properties that are very similar to those of previously characterized integrin alpha/beta heterodimeric receptors for ECM proteins; and (c) can be incorporated into phosphatidylcholine vesicles that then bind specifically to substrates coated with laminin or collagen IV but not fibronectin. Thus, the ligand-binding specificity of the liposomes containing the purified PC12 integrins closely parallels the substrate-binding preference of intact PC12 cells. These results demonstrate that mammalian integrins purified from a neuronal cell line can, when incorporated into lipid vesicles, function as receptors for laminin and type IV collagen.
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PMID:Purification and characterization of mammalian integrins expressed by a rat neuronal cell line (PC12): evidence that they function as alpha/beta heterodimeric receptors for laminin and type IV collagen. 284 50

Adhesion studies with cryotome sections of human kidney and lung respectively uroepithelial cells together with blocking experiments with competitive carbohydrates suggested that specific attachment of S. saprophyticus strain S 1 to host cells apparently is mediated by lectins. Accordingly, microbial lectin blocking with specific glycoconjugates or lectin dysfunction (after treatment of bacteria with subinhibitory concentrations of tunicamycin) significantly decreased staphylococcal adherence to epithelial cells. Chemiluminescence measurements of human polymorphonuclear leukocyte (PMN) function yielded results suggesting importance of lectin-receptor interaction in phagocytosis, too, since PMN activity was significantly decreased after staphylococcal lectin blocking or dysfunction.
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PMID:Lectin-mediated cell-attachment and phagocytosis of Staphylococcus saprophyticus strain S1. 322 39

The effect of various lectins and sugars on adhesion of five strains of Candida albicans to buccal and vaginal epithelial cells in vitro was investigated. Adhesion of C. albicans GDH 2346 was inhibited primarily by L-fucose and winged-pea lectin, whereas adhesion of strain GDH 2023 was inhibited by N-acetyl-D-glucosamine, or D-glucosamine, and wheat-germ agglutinin. Three other strains of C. albicans (MRL 3153, GRI 681 and GRI 682) gave results similar to those obtained with strain GDH 2346. Extracellular polymeric material (EP) isolated from strain GDH 2346 inhibited adhesion of strains MRL 3153, GRI 681 and GRI 682 by more than 50%, but that of strain GDH 2023 by only 30%. EP from strain GDH 2023 had little or no effect on the adhesion of any other yeast strain. Lectin-like proteins with affinities for L-fucose, N-acetyl-D-glucosamine and D-mannose were detected in EP from all five strains in different amounts. These results indicate that there are at least two types of adhesion mechanism and that glycosides containing L-fucose or N-acetyl-D-glucosamine can function as epithelial cell receptors for C. albicans.
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PMID:Role of glycosides as epithelial cell receptors for Candida albicans. 330 64

Candida albicans cells were treated with alkali and acid to extract preferentially the cell wall alpha-mannan. Cells were recovered at three stages, as extraction proceeded from mild to more extensive: Alk-1, Alk-2 and Alk + Acid. Yeast adhesion to human epithelial cells was then examined with an in-vitro adherence assay. Yeasts from all three stages of extraction adhered in significantly lower numbers to buccal mucosal cells than did unextracted yeasts. Adhesion was as low for Alk-1 cells as for those submitted to more complete mannan extraction. When yeast cells from all three stages were treated with Concanavalin A (Con A), a lectin probe with strong affinity for yeast alpha-mannans, and then subjected to the adherence assay, there was no significant change in adhesion. When yeast agglutinability by Con A was examined in tests with treated and untreated yeast cells, abundant agglutination occurred only with the untreated cells. However, Alk-1 cells, though lacking in adhesive capacity towards mucosal cells, showed significant agglutination. The results suggest that candidal adhesion is mediated by an alkali-soluble, mannan-containing moiety(ies) which appears to be lost early in the extraction process. Blockage of this moiety by Con A inhibits the adhesion of unextracted cells. Extracted cells lack this moiety but still possess enough structural mannan for Con A recognition and agglutination.
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PMID:Studies on cell adhesion and concanavalin A-induced agglutination of Candida albicans after mannan extraction. 330 22

Staphylococcus saprophyticus strains S 1 and S 35 demonstrated lectin like surface receptors specific for N-acetylgalactosamine (S 1) or N-acetylneuraminic acid (S 35). Adhesion assays with human uroepithelial cells together with blocking experiments with competitive carbohydrates suggested that specific attachment of S. saprophyticus to host cells is apparently mediated by lectins. Staphylococcal lipoteichoic acid (LTA) was also shown to interfere with S. saprophyticus adherence to human uroepithelial cells.
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PMID:The role of lectins and lipoteichoic acid in adherence of Staphylococcus saprophyticus. 340 61

Adhesion between spermatozoa and the egg's extracellular coat, the zona pellucida, involves the sperm's zona binding proteins (ZBP) and their interaction with the carbohydrate residues of the zona. To investigate this interaction in more detail, a purified nonenzymatic ZBP, the rabbit sperm membrane autoantigen, RSA, was used. RSA-zona binding was demonstrated on nitrocellulose blots and by using the Denny-Jaffe crosslinking reagent which identified an 87,000 molecular weight zona component as the ligand for RSA. The RSA-zona binding was of high affinity with a dissociation constant of 5.6 X 10(-13) M. Furthermore, the binding of capacitated spermatozoa to intact zona was inhibited in the presence of RSA. Characterization of the RSA-zona interaction with a variety of simple and complex carbohydrates indicated that the sulfated, complex carbohydrates fucoidin, dextran sulfate, chondroitin sulfate B, and heparin strongly inhibited RSA-zona binding while chondroitin sulfates A and C, cholesterol-3-sulfate, and monosaccharides such as galactose inhibited RSA-zona binding only weakly. It is concluded that RSA functions as a sperm lectin-like molecule to bind the spermatozoon to the zona pellucida.
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PMID:Characterization of the rabbit sperm membrane autoantigen, RSA, as a lectin-like zona binding protein. 341 Jan 59

Cell-mediated recognition can operate at different levels of complexity and specificity based largely on the time of appearance of effector mechanisms during the course of evolution. Antigen-specific cytotoxic T lymphocytes require both T cell receptor genes and lectin-like cell adhesion molecules (LFA-1, LFA-2, lymphocyte function-associated) to initiate and maintain stable effector target cell conjugates. Natural killer (NK) cells, on the other hand, do not require expression of T cell receptor genes in the recognition and killing of tumor cells and virally infected cells. Adhesion is mediated by a family of glycoprotein molecules, of which the LFA-1 and LFA-2 molecules appear as the most likely candidates. NK-mediated cytolysis proceeds in the absence of MHC restriction, but nevertheless appears to be triggered by depressed levels of self MHC products on the cell surface of target cells. Finally, interleukin 2-dependent, cloned cell lines with NK-like cytotoxic activity should no longer be considered as bona-fide NK cells but rather reclassified as a subset of T cells which displays NK function.
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PMID:T cell receptor gene rearrangements in cells with natural killer activity in the mouse. 355 72

Lewis lung carcinoma cells are able to bind sugar residues, mainly alpha-D-glucosyl and alpha-D-mannosyl derivatives as assessed by fluorescent neoglycoproteins binding assay. We have investigated the binding efficiency and shown that: 3LL tumor cells are heterogeneous with regards to their capability to recognize neoglycoproteins, as shown by fluorescence microscopy and flow cytofluorometry analyses; basically two distinct subpopulations could be evidenced which were called glucose-receptor-rich (or glucose-specific lectin-rich, GLR 3LL) and glucose-receptor-poor (or glucose-specific lectin-poor, GLP 3LL) cells; those two subpopulations could be separated on the basis of their binding properties to neoglycoprotein-substituted microcarriers onto which GLR 3LL cells were able to rapidly adhere (2 h) while GLP 3LL cells were not. Some aspects of the biological behavior of these two selected populations were investigated in order to determine the possible involvement of 3LL cell membrane sugar receptors in cell-cell recognition and adhesion to other cells: namely C57 B1/6 mouse pulmonary cells maintained in primary culture. The two 3LL sublines bind to pulmonary cells but their adhesion kinetics were markedly different. Adhesion inhibition studies showed the adhesion process to be dependent upon the specificity of membrane lectins present on both the tumor cell surface (alpha-D-glucose-specific) and on the pulmonary cells (alpha-L-fucose-specific). Surface sugar-specific receptors on mouse pulmonary cells were shown to bind beta-D-galactose-, alpha-L-fucose and alpha-L-rhamnose substituted serum albumin. A neoglycoprotein bearing alpha-L-rhamnose residues was an efficient binder under the conditions of cell adhesion experiments and a potent cell adhesion inhibitor. A fucose-containing neoglycoprotein was shown to have a high inhibitory activity when used concomitantly to alpha-D-glucose-containing neoglycoproteins. Adhesion inhibition experiments, performed with cells the sugar specific receptors of which have been selectively inactivated, showed that the alpha-L-fucose specific receptors on pulmonary cell surface are partly responsible for the specificity of this cell-cell recognition process.
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PMID:Involvement of membrane sugar receptors and membrane glycoconjugates in the adhesion of 3LL cell subpopulations to cultured pulmonary cells. 380 41

The main function of the macrophages, which is to ingest and degrade any foreign molecules or particles penetrating the organism, appears in the development of the different structures implicated in endocytic activity. The macrophage's high endocytic property first appears in its irregular shape and the large number of extensions of the cell membrane, allowing the rapid capture of extra-cellular material. Adhesion between macrophage cell surface and molecules or particles is greatly enhanced by the presence of varied kinds of receptors: lectin-like receptors which bind specific sugars or highly specific receptors such as Fc and C3b receptors, which increase phagocytosis of opsonized microbes. The microbicidal properties reside in part in the production of superoxide anions which result from the activity of a NAD(P)H oxidase. This enzyme is located in the plasma membrane. Its activity could be demonstrated with a cytochemical method, on the cell surface and along the phagosome membrane. It is, however, very weak in resident macrophages and increases after stimulation or activation. The second kind of bactericidal property corresponds to cationic proteins located in lysosomes. After fusion between lysosomes and phagosomes, they contribute to microbe killing by permeabilizing microbe envelopes. Lysosomes, which contain diverse acid hydrolases and are responsible for the degradation of ingested material, play a crucial role in macrophage endocytic activity. Their number increases in parallel with endocytic activity during macrophage differentiation and is particularly high after ingestion of degradable material. Contrary to polymorphonuclear leukocytes, macrophage is very poor in granules containing peroxidase. The latter, which are rather abundant in monocytes, disappear during macrophage maturation. They do not seem thus to be implicated in macrophage microbicidal activity. Endocytosis is accompanied by rapid and intense exchanges between the different membrane compartments of the cell (plasma membrane, pinosomes or phagosomes, endosomes, lysosomes, Golgi apparatus, etc.). These exchanges seem to occur by transitory fusions between vesicles coming from different compartments, rapidly followed by their recycling to their original compartment. This system of membrane shuttle has been clearly observed after formation of phagosomes or pinosomes in which the internalized plasma membrane is recycled back to the cell surface within a few minutes after their formation. This membrane traffic is especially intense in macrophages, the endocytic activity of which is very high, but it also exists in all cell types.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Relationship between ultrastructure and specific functions of macrophages. 391 Mar 40


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