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)

Three families of cell-surface proteins are largely responsible for the adherence of leukocytes to cells and matrices: integrins, immunoglobulin (Ig)-related molecules and selectins. Blood monocytes express beta 1 integrins VLA-4, -5 and -6 and beta 2 integrins CD11a/CD18, CD11b/CD18 and CD11c/CD18. These cells also express the Ig-related molecules ICAM-1, -2 and -3, ligands for the beta 2 integrins. In addition, monocytes express L-selectin and the oligosaccharides Lex and sialyl Lex, ligands for the endothelial selectins E- and P-. In vitro studies with blocking antibodies have identified adhesion molecules participating in the adherence of monocytes to one another, to T lymphocytes and to vascular endothelial cells. These antibodies also block adhesion-dependent monocyte activities, such as cytotoxicity of tumor cells, antigen presentation, phagocytosis of large particles, induction of cytokine secretion, formation of multinucleated giant cells and HIV-induced syncytium formation. In vivo studies in animals have demonstrated participation of L-selectin and CD11b/CD18 in monocyte accumulation in inflamed peritoneum. Moreover, treatment with anti-CD11b antibodies potentiates primary listeriosis and inhibits the macrophage recruitment and granuloma formation, and anti-CD18 antibodies block ear swelling in Mycobacterium tuberculosis-immunized animals following challenge with PPD. Adhesion molecules may also play key roles in the pathogenesis of tuberculosis and AIDS.
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PMID:Adhesion molecules mediating recruitment of monocytes to inflamed tissue. 771 61

Although integrins are known to mediate adhesive binding of cells to the extracellular matrix, their role in mediating cellular growth, morphology, and differentiation is less clear. To determine more directly the role of the alpha 2 beta 1 integrin, a collagen and laminin receptor, in mediating the collagen-dependent differentiation of mammary cells, we reduced expression of the integrin by the well differentiated human breast carcinoma cell line, T47D, by stably expressing alpha 2 integrin antisense mRNA. Flow cytometry demonstrated that the antisense-expressing clones had levels of alpha 2 beta 1 integrin on their surfaces that were decreased by 30-70%. Adhesion of antisense-expressing clones to both collagens I and IV was decreased relative to controls in a manner that correlated with the level of cell surface alpha 2 beta 1 integrin expression. Adhesion to fibronectin and laminin were not affected. Motility across collagen-coated filters in haptotaxis assays was increased for only those clones that exhibited intermediate levels of adhesion to collagen, suggesting that an intermediate density of cell-surface alpha 2 beta 1 integrin optimally supports cell motility. When cultured in three-dimensional collagen gels, T47D cells organized in a manner suggestive of a glandular epithelium. In contrast, antisense-expressing clones with decreased alpha 2 beta 1 integrin were not able to organize in three-dimensional collagen gels. The growth rate of T47D cells was reduced when the cells were cultured in three-dimensional collagen gels. Unlike adhesion, motility, and morphogenesis, growth rates were unaffected by reduction of alpha 2 beta 1 integrin expression. Our results suggest that adhesive interactions mediated by a critical level of surface alpha 2 beta 1 integrin expression are key determinants of the collagen-dependent morphogenetic capacity of mammary epithelial cells.
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PMID:Alteration of collagen-dependent adhesion, motility, and morphogenesis by the expression of antisense alpha 2 integrin mRNA in mammary cells. 776 4

We have previously shown that lymphocytic cells bind to cultured syncytiotrophoblast and that this may be important in the lymphocyte-mediated infection of trophoblast with the human immunodeficiency virus (HIV). Leukocyte-trophoblast adhesion may also have implications for normal trophoblast function. The following experiments were designed to characterize the adhesion systems that mediate the attachment of lymphocytic cells to trophoblast. Adhesion was assayed by labelling lymphocytic MOLT-4, clone 8 cells with the fluorescent marker, calcein-AM, and then incubating them with primary cultures of human syncytiotrophoblast. Adhesion was stimulated by pretreatment of the trophoblast cultures with several cytokines either alone or together. These included tumor necrosis factor-alpha (TNF-alpha), granulocyte/macrophage-colony stimulating factor (GM-CSF), interleukin-1 beta (IL-1 beta) and interferon-gamma (IFN-gamma). Stimulation was time- and dose-dependent. In contrast, preincubation of trophoblast cultures with anti-TNF-alpha antibodies for 2 days reduced MOLT adhesion by almost 50%. Preincubation with other anti-cytokine antibodies had no significant effect on adhesion. In other experiments, adhesion was measured in the presence of antibodies to known adhesion molecules. Adhesion was reduced by 50% in the presence of antibodies to alpha 4 integrin or beta 1 integrin. When present together, these antibodies reduced adhesion by almost 85%. Incubation in the presence of antibodies to the very late activation antigen-4 (VLA-4; alpha 4 beta 1 integrin) counter-receptors, VCAM-1 and CS-1, was without effect. Adhesion was also unaffected by antibodies to LFA-1, ICAM-1, ICAM-2, LFA-2, or LFA-3. These results suggest that adhesion is mediated by an adhesion system consisting of lymphocyte VLA-4 (alpha 4 beta 1) and an as yet unidentified counter receptor on trophoblast.
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PMID:Effect of cytokines and anti-adhesion molecule antibodies on the adhesion of lymphocytic cells to human syncytiotrophoblast. 780 71

We have examined the mechanism by which human epidermal keratinocytes adhere to the A/B1/B2 (alpha 1 beta 1 gamma 1) form of laminin. Adhesion could be completely inhibited with an antibody to the beta 1 integrin subunit or a combination of antibodies recognising the alpha 2 beta 1, alpha 3 beta 1 and alpha 6 beta 4 integrins. Keratinocytes adhered in the presence of magnesium and manganese ions, but calcium ions did not support adhesion and inhibited adhesion when combined with magnesium and manganese. The effects of anti-integrin antibodies (including a stimulatory antibody to the beta 1 subunit) were not influenced by specific cations, with the exception that inhibition by an antibody to alpha 2 beta 1 was abrogated by the presence of manganese ions. The E3 and E8 proteolytic fragments of laminin did not support keratinocyte adhesion and heat inactivation of the E8 site in intact laminin did not reduce adhesion. Three laminin fragments that did support adhesion were P1, E4 and E1X-Nd, P1 activity being attributable at least in part to the RGD site; antibody blocking experiments suggested that adhesion to these fragments was primarily via alpha 3 beta 1. The synthetic peptide GD-6, derived from the carboxy terminus of the laminin A chain (included within E3) did support adhesion, but the significance of this observation is unclear, since a scrambled control peptide could also support adhesion. In conclusion, keratinocyte adhesion to A/B1/B2 laminin involves three integrins and multiple binding sites that are different from those defined previously.
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PMID:Adhesion of human epidermal keratinocytes to laminin. 782 May 34

Twelve different human primary and metastatic Ewing's sarcoma (ES) and primitive peripheral neuroectodermal tumour (pPNET) cell lines were examined by fluorocytometric analysis for the expression of alpha 1, alpha 2, alpha 3 and alpha 6 very late antigen (VLA) beta 1-integrins. VLA-alpha 1, was abundantly expressed on all typical ES cell lines and pPNET cell lines, while absent from atypical (large cell) ES cells. VLA-alpha 2 was displayed on some ES and pPNET cell lines. In two different pPNET cell lines, derived from the same patient, VLA-alpha 2 expression was considerably higher on primary cells compared with metastatic cells. VLA-alpha 3 was exclusively expressed on pPNET cell lines. Expression of VLA-alpha 6 was higher on metastatic than on primary ES and pPNET cells. Adhesion assays on purified extracellular matrix (ECM) proteins, using monospecific adhesion-blocking antibodies, disclosed VLA-1 (alpha 1 beta 1) on typical ES cells and pPNET cells, and VLA-2 (alpha 2 beta 1) on atypical ES cells, as dual collagen type IV (COIV)/laminin (LM) binding sites, and VLA-6 (alpha 6 beta 1) as a specific LM binding site. Treatment of typical ES cells and pPNET cells for up to 48 h with recombinant human interferon-gamma (rhIFN gamma) and tumour necrosis factor-alpha (rhTNF alpha) upregulated alpha 1 and beta 1 expression, concomitant with an increase in cell adhesion to COIV and LM. Alternatively, these cytokines downregulated the expression of alpha 2, alpha 6 and beta 1 on atypical ES cells, concomitant with a decrease in the adhesion to COIV and LM. In conclusion, these findings suggest that the difference in repertory of CO and LM integrin receptors on ES cells and pPNET cells reflects tumour status and degree of differentiation. Furthermore, our data indicate that IFN gamma- and TNF alpha-mediated alteration in the level of expression of distinct VLAs on ES and pPNET cells is correlated with changes in the adhesive behaviour of these tumour cells.
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PMID:Expression of functional very late antigen-alpha 1, -alpha 2, -alpha 3 and -alpha 6 integrins on Ewing's sarcoma and primitive peripheral neuroectodermal tumour cells and modulation by interferon-gamma and tumour necrosis factor-alpha. 785 12

Oral lichen planus exhibits features of a mucosal type IV immunopathologic process. Adhesion molecules involved in the trafficking and homing of T lymphocytes to the subepithelial compartment were assessed by immunohistochemical methods. Laminin, type IV collagen and type VII collagen extracellular matrix components at the epithelial-connective tissue junction are significantly increased and serve as ligands for beta 1 integrins on lymphocyte membranes. Endothelial-associated intercellular adhesion molecule 1 and extracellular matrix basement membrane components are also significantly increased in the submucosa. Keratinocyte expression of major histocompatibility complex class II molecules and intercellular adhesion molecule 1 may serve as ligands for lymphocyte T cell receptor complex and beta 2 integrins, respectively. These adhesion molecules are probably involved in the trafficking of lymphocytes to the epithelial connective tissue interface in response to as of yet undefined antigens.
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PMID:Leukocyte adhesion molecules in oral lichen planus: a T cell-mediated immunopathologic process. 787 Apr 74

Adhesion molecules are involved in the recruitment of leucocytes to sites of inflammation. In this study, we determined the expression of several adhesion molecules on isolated human alveolar type II pneumonocytes. Type II pneumocytes were isolated from 10 normal lung specimens, by enzymatic digestion with dispase, followed by metrizamide gradient centrifugation and panning on immunoglobulin G (IgG)-coated plastic dishes. With the freshly isolated type II cells, immunostaining was performed using a sensitive immunoperoxidase slide technique. In all cases, 60-90% of type II cells were positive for intercellular adhesion molecule-1 (ICAM-1) (CD54). A minor portion of type II cells expressed the alpha 4 (CD49d) subunit of the beta 1-integrins, and the alpha-v (CD51) subunit of the vitronectin receptor. CD11a, CD11b, CD11c, CD18, CD49b, and CD49f failed to demonstrate any immunostaining with type II cells. In conclusion, the observation of the expression of ICAM-1 and, to a lesser degree, of some integrin subunits, may indicate that alveolar type II cells participate in local immune and inflammatory responses.
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PMID:ICAM-1 and integrin expression on isolated human alveolar type II pneumocytes. 791 65

Human peripheral blood eosinophils adhered specifically to microtitre plates coated with plasma fibronectin (Fn) in a dose- and time-dependent fashion. Adhesion was optimal at 60 min at a concentration of 100 micrograms/ml. Adherence to Fn was up-regulated by platelet-activating factor (PAF; optimum concentration of 10(-6) M) and was significantly inhibited by a polyclonal anti-Fn antibody (P < 0.05). The following evidence suggested that eosinophil adhesion to Fn was mediated by alpha 4 beta 1: (1) eosinophil adherence to Fn was not inhibited by an Arg-Gly-Asp-Ser (RGDS) synthetic peptide; (2) there was a dose-dependent adherence of eosinophils to microtitre plates coated with the 40,000 MW proteolytic fragment of Fn that contains the CS-1 alpha 4 beta 1 binding region, whereas adherence to the 120,000 MW chymotryptic fragment of Fn, which contains the RGD-dependent binding site, was weak and only observed at high concentrations (> 250 micrograms/ml); (3) significant inhibition of eosinophil adherence to Fn was achieved by monoclonal antibodies (mAb) against the alpha chain of VLA-4 but not by a mAb against CD45 or a mouse myeloma antibody as negative controls. After adhesion to Fn, eosinophils were investigated for their capacity to release leukotriene C4 in response to stimulation with a suboptimal concentration of calcium ionophore (2 x 10(-6) M). Significant enhancement of release was detected with Fn-coated plates but not with the control bovine serum albumin (BSA) (P < 0.01). Furthermore, this enhancement was significantly inhibited by the alpha 4 beta 1 mAb HP2/1 (P < 0.05) but not by an anti-CD45 mAb. From these studies we conclude that (1) alpha 4 beta 1 (VLA-4) integrin is a major receptor for Fn on human eosinophils and (2) adhesion to Fn may prime eosinophils for mediator release during allergic inflammation.
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PMID:Adhesion to fibronectin primes eosinophils via alpha 4 beta 1 (VLA-4). 792 93

Modification of non-immunological cell adhesion properties plays a major role in the decrease in metastatic ability observed after transfection of the H-2Kb gene in H-2-negative B16-derived melanoma clone cells. To investigate the role played by different class-I major histocompatibility complex (MHC) genes on non-immunological properties relevant for metastasis, transfection with the H-2Db gene alone or in conjunction with the H-2Kb gene was performed. H-2Db gene transfection did not modify either metastatic potential or non-immunological cell adhesion properties. Double KbDb transfectants showed a decreased metastatic ability when compared to control clones and to Db transfectants; a decrease in homotypic adhesive ability was also observed, even though not in all clones studied: therefore expression of the Db gene is also relevant. The mechanisms of homotypic cell adhesion were studied and found to be dependent upon temperature and divalent cations. Adhesion was partially inhibited by an antiserum directed against the beta 1 integrin subunit, whereas anti-alpha IIb beta 3 was ineffective. Cell pre-treatment with anti-beta 1 serum reduced metastatic ability. A decreased expression of alpha 4 and alpha 6 integrin subunits was observed in Kb clones, whereas no difference in the levels of some homophilic cell adhesion molecules, such as N-CAM and alpha IIb beta 3, was found. Adhesion required the activity of tyrosine kinases, as suggested by the decreased adhesive properties and impaired metastatic ability of cells pre-treated with the tyrosine-kinase-inhibitor genistein. These results are compatible with involvement of integrin molecules of the beta 1 family in the adhesive ability of these cells. Our data show that: (a) immunological and non-immunological effects of MHC transfection are correlated and depend on the class-I gene used, suggesting that MHC gene therapy can be highly successful only if appropriate MHC genes are transfected; (b) non-immunological cell-adhesion properties modified after MHC transfection could be related to an impairment of integrin-mediated adhesive interactions.
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PMID:H-2Kb and H-2Db gene transfections in B16 melanoma differently affect non-immunological properties relevant to the metastatic process. Involvement of integrin molecules. 792 28

A correlation between changes in protein kinase C (PKC) activity and tumor metastasis has been reported previously with several murine tumor cell lines. Treatment of a human metastatic melanoma cell line, M24met, with phorbol ester, phorbol-12-myristate-13-acetate (PMA), followed by injection into the tail vein of scid mice doubled pulmonary metastasis. Adhesion of M24met cells exposed to PMA, was enhanced to collagens I and IV, but not to laminin or fibronectin, suggesting a change in specific adhesion receptors on the tumor cells. Treatment of M24met cells with PMA did not affect de novo synthesis of integrin subunits (alpha 2, alpha 3, beta 1) known to form collagen receptors. However, PMA stimulated the phosphorylation of integrin subunits alpha 3 and beta 1 on serine. Therefore, PMA effects on metastasis and cell adhesion may occur through PKC-mediated phosphorylation of integrins.
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PMID:Modulation of human melanoma cell metastasis and adhesion may involve integrin phosphorylation mediated through protein kinase C. 794 69


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