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)

Treatment of human endothelial cells with cytokines such as interleukin-1, tumor necrosis factor-alpha (TNF-alpha) or interferon-gamma induces the expression of specific leukocyte adhesion molecules on the endothelial cell surface. Interfering with either leukocyte adhesion or adhesion protein upregulation is an important therapeutic target as evidenced by the potent anti-inflammatory actions of neutralizing antibodies to these ligands in various animal models and in patients. In the present study we report that cotreatment of human endothelial cells with certain hydroxyflavones and flavanols blocks cytokine-induced ICAM-1, VCAM-1, and E-selectin expression on human endothelial cells. One of the most potent flavones, apigenin, exhibited a dose- and time-dependent, reversible effect on adhesion protein expression as well as inhibiting adhesion protein upregulation at the transcriptional level. Apigenin also inhibited IL-1 alpha-induced prostaglandin synthesis and TNF-alpha-induced IL-6 and IL-8 production, suggesting that the hydroxyflavones may act as general inhibitors of cytokine-induced gene expression. Although apigenin did not inhibit TNF-alpha-induced nuclear translocation of NF-kappa B(p50(NFKB1)/p65(RelA)) we found this flavonoid did inhibit TNF-alpha induced beta-galactosidase activity in SW480 cells stably transfected with a beta-galactosidase reporter construct driven by four NF-kappa B elements, suggesting an action on NF-kappa B transcriptional activation. Adhesion of leukocytes to cytokine-treated endothelial cells was blocked in endothelial cells cotreated with apigenin. Finally, apigenin demonstrated potent anti-inflammatory activity in carrageenan induced rat paw edema and delayed type hypersensitivity in the mouse. We conclude that flavonoids offer important therapeutic potential for the treatment of a variety of inflammatory diseases involving an increase in leukocyte adhesion and trafficking.
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PMID:Flavonoids inhibit cytokine-induced endothelial cell adhesion protein gene expression. 763 22

Adhesion molecules are important in T-cell trafficking to sites of inflammation. We determined levels of circulating vascular cell adhesion molecule-1 (VCAM-1), L-selectin, and E-selectin in the serum of 147 patients with definite multiple sclerosis of the remitting-relapsing or secondary progressive type. Soluble VCAM-1 and L-selectin concentrations were increased compared to levels in a large group of control subjects. Levels were highest in patients with gadolinium-enhancing lesions on magnetic resonance imaging (VCAM-1: 1,011 +/- 276 vs 626 +/- 87 ng/ml; L-selectin: 1,130 +/- 272 vs 793 +/- 207 ng/ml [mean +/- standard deviation]; p < 0.0001 vs patients without enhancing lesions). Serum levels of soluble tumor necrosis factor receptor (60 kd) were also raised (2.64 +/- 1.23 vs 2.17 +/- 0.69 ng/ml in subjects with other neurological diseases and 2.1 +/- 0.77 ng/ml in healthy control subjects; p < 0.05). Soluble VCAM-1 and L-selectin levels were correlated to concentrations of soluble tumor necrosis factor receptor. In 13 patients with viral encephalitis, similar observations were made. Raised levels of soluble VCAM-1 and L-selectin probably reflect cytokine-induced endothelial cell and T-lymphocyte/monocyte activation occurring in the process of T-cell migration into the central nervous system. Tumor necrosis factor-alpha may be critically involved.
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PMID:Circulating adhesion molecules and tumor necrosis factor receptor in multiple sclerosis: correlation with magnetic resonance imaging. 754 73

The Very Late Antigen-4 receptor (VLA-4) (alpha 4 beta 1) is constitutively expressed on leukocytes and plays a role in cell trafficking, activation and development through its interaction with two alternative ligands, Vascular Cell Adhesion Molecule (VCAM-1) and fibronectin (FN). VLA-4-dependent cell adhesion is augmented by various stimuli, such as divalent cations, certain beta 1-specific monoclonal antibodies (mAbs) and cell activation. However, the steps of the adhesive process which they affect are currently undefined. In order to investigate whether or not these stimuli affect the primary step, VLA-4/ligand binding, we employed a recombinant VCAM-IgG fusion protein (VCAM-Ig) as a soluble ligand for VLA-4. Using this soluble ligand, we have directly demonstrated that the VLA-4 receptor can exist in at least three different affinity states on the cell surface. Two distinct high affinity states are induced on normal peripheral blood T cells, one by the anti-beta 1 mAb TS2/16, and one of 15-20 fold higher affinity by the divalent cation Mn2+. Interestingly, activation through the T cell receptor (TcR), through CD31 or by the Macrophage Inflammatory Protein-1 beta chemokine (MIP-1 beta) do not detectably increase VLA-4 affinity although they do augment VLA-4 dependent cell adhesion in vitro. Thus, VCAM-Ig binding defines high affinity VLA-4 receptors, revealing unique effects of the TS2/16 mAb and Mn2+ cations in vitro, and distinguishes VLA-4/VCAM interactions from subsequent steps in cell adhesion.
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PMID:Vascular cell adhesion molecule (VCAM)-Ig fusion protein defines distinct affinity states of the very late antigen-4 (VLA-4) receptor. 758 6

Adhesion of hematopoietic progenitor cells to marrow-derived adherent cells has been noted for erythroid, myeloid, and lymphoid precursors. In this report, we have characterized very late antigen (VLA) integrin expression on normal CD34+ marrow progenitors, on leukemic cell lines, and on blasts from patients with acute myelogenous or monocytic leukemias. CD34+ progenitor cells expressed the integrin beta 1 chain (CD29), VLA-4 alpha (CD49d), and VLA-5 alpha (CD49e). The myeloid lines KG1 and KG1a also expressed CD49d and CD49e as did the Mo7e megakaryoblastic line. CD29, CD18, and CD11a were also present on each of these cell lines. Only the Mo7e line expressed the cytoadhesins GPIIbIIIa or GPIb. Binding of KG1a to marrow stroma was partially inhibited by antibodies to CD49d and its ligand, vascular cell adhesion molecule (VCAM-1). The majority of leukemic blasts studied expressed CD49d and CD49e as well. Blasts from patients with acute myelomonocytic leukemia consistently bound to stroma at levels greater than 20%, and adhesion to stroma could in some cases be partly inhibited by anti-CD49d. No role for glycosylphosphatidyl-inositol (GPI)-linked structures was demonstrated in these binding assays because the adhesion of leukemic blasts to stroma was not diminished after treatment with phosphatidylinositol-specific phospholipase C (PI-PLC). These studies indicate that CD34+ myeloid progenitors, myeloid leukemic cell lines, and leukemic blasts possess a similar array of VLA integrins. Their functional importance individually or in combination with other mediators of attachment in adhesion, transendothelial migration, and differentiation has yet to be fully elucidated.
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PMID:Expression of integrins and examination of their adhesive function in normal and leukemic hematopoietic cells. 767 62

Lymphocyte migration from blood into tissue depends on integrin-mediated adhesion to endothelium. Adhesion requires not only integrin ligands on the endothelium, but also activation signals because T-cell integrins cannot bind well until they are activated. The physiological 'triggers' for T-cell adhesion are unknown, but cytokines may be good candidates as they are released during inflammation and trigger adhesion in neutrophils and monocytes. We have identified a cytokine, macrophage inflammatory protein-1 beta (MIP-1 beta), that induces both chemotaxis and adhesion of T cells; MIP-1 beta is most effective at augmenting adhesion of CD8+ T cells to the vascular cell adhesion molecule VCAM-1. We reasoned that, as cytokines in vivo will be rapidly washed away, MIP-1 beta might be bound to endothelial surfaces and so induce adhesion in its immobilized form. Here we show that: (1) MIP-1 beta is present on lymph node endothelium; (2) immobilized MIP-1 beta induces binding of T cells to VCAM-1 in vitro. MIP-1 beta was immobilized by binding to proteoglycan: a conjugate of heparin with bovine serum albumin and cellular proteoglycan CD44 were both effective. We propose that MIP-1 beta and other cytokines with glycosaminoglycan-binding sites will bind to and be presented by endothelial proteoglycans to trigger adhesion selectively not only of lymphocyte subsets, but also of other cell types.
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PMID:T-cell adhesion induced by proteoglycan-immobilized cytokine MIP-1 beta. 842 88

Self-renewal and differentiation of B-cell precursors is dependent on interactions with bone marrow (BM) stromal cells and associated extracellular matrix. We have recently developed an interleukin (IL)-7-dependent, BM-derived stromal cell culture that supports the growth of normal human B-cell precursors. In the current study, we have characterized the constitutive expression, cytokine-regulated expression, and function of adhesion molecules on BM stromal cells that are critical for adhesion of B-cell precursors. Flow cytometric analysis showed that cultured adult BM stromal cells expressed higher constitutive levels of vascular cell adhesion molecule (VCAM)-1 than intercellular adhesion molecule (ICAM)-1 (CD54). IL-1 beta upregulated VCAM-1 and CD54 in a dose-dependent manner, whereas IL-4 upregulated VCAM-1, but had no effect on CD54. In contrast, transforming growth factor (TGF)-beta decreased the level of BM stromal cell VCAM-1. Using an assay to measure the adhesion of 51Cr-labeled B-cell precursors to BM stromal cells, we observed a direct correlation between cytokine-regulated levels of VCAM-1 and the capacity of stromal cells to support the adhesion of B-cell precursors. Blocking studies using a panel of monoclonal antibodies (MoAb) showed that adhesion of B-cell precursors to untreated and cytokine-treated (IL-1 beta, IL-4) BM stromal cells was mediated by very late antigen (VLA)-4 (CD49d/CD29) and VCAM-1. Adhesion of B-cell precursors could also be enhanced by direct stimulation with MoAb to the CD29 subunit. Our collective results indicate that B-cell precursor/BM stromal cell adhesion is mediated by a VLA-4-VCAM-1 interaction, which in turn can be regulated at the level of the BM stromal cell by cytokines that specifically increase or decrease cell surface VCAM-1.
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PMID:Regulation of human B-cell precursor adhesion to bone marrow stromal cells by cytokines that exert opposing effects on the expression of vascular cell adhesion molecule-1 (VCAM-1). 768 14

Expression of adhesion molecules on endothelial cells (EC) can be up-regulated or induced by cytokines. The aim of the present study was to investigate the effect of IL-4 on both the expression of adhesion molecules on EC and monocyte adhesion to EC. Flow cytometric analysis showed that VCAM-1 expression on EC was up-regulated after stimulation with IL-4 for 24 h, whereas the expression of E-selectin (formerly called endothelial leucocyte adhesion molecule-1 (ELAM-1)) was not enhanced, and that of intercellular adhesion molecule-1 (ICAM-1) only slightly. The adhesion of monocytes to EC increased to maximum values upon stimulation of EC with IL-4 for 24 h. Coating of monocytes with MoAb against the integrin beta 2-subunit (CD18) significantly inhibited their adhesion to IL-4-stimulated EC; maximal inhibition was found when monocytes were coated with anti-CD18 MoAb in combination with MoAb against CD49d (the alpha-chain of VLA-4), whereas no inhibition was found when monocytes were coated only with MoAb against CD49d. Monocyte adhesion was not significantly inhibited when IL-4-stimulated EC were coated with MoAbs against ICAM-1 or VCAM-1 alone or in combination. Adhesion of monocytes was inhibited to a greater extent when in addition to coating of monocytes with MoAb against CD18 the EC were coated with MoAb against VCAM-1. From these results we conclude that monocytes bind to IL-4-stimulated EC via interaction of CD11/CD18 molecules on the monocytes with an as yet unknown endothelial ligand, and interaction of VLA-4 on monocytes with VCAM-1 on EC.
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PMID:Increased adhesion of human monocytes to IL-4-stimulated human venous endothelial cells via CD11/CD18, and very late antigen-4 (VLA-4)/vascular cell adhesion molecule-1 (VCAM-1)-dependent mechanisms. 768 78

Adhesion molecules probably are required for the migration of T lymphocytes to inflamed tissues, but the roles of these molecules have yet to be understood in the pathogenesis of inflammatory diseases such as multiple sclerosis. The adhesion of an SJL murine T cell clone specific for myelin basic protein (MBP) to endothelial cells (ECs) from SJL newborn brain microvessels was examined. Sixty percent of the 2 x 10(4) T cell clones stimulated once every 2 weeks with MBP were bound to ECs, whereas less than 5% of the same number of lymphocytes from peripheral lymph nodes were bound. However, binding was not central nervous system (CNS)-specific. Monoclonal antibody to VLA-4 or VCAM-1 partially inhibited the binding of the T cell clone to ECs. Binding of the T cell clone to ECs increased when the latter were incubated with IL-1 or TNF, but was not inhibited by anti-VLA-4 or VCAM-1. We suggest that the VLA-4/VCAM-1 pathway functions in the binding of the T cell clone specific for MBP to brain ECs but that adhesion molecules other than VLA-4/VCAM-1 are involved because anti-VLA-4 and anti-VCAM-1 did not produce complete inhibition.
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PMID:Binding of an SJL T cell clone specific for myelin basic protein to SJL brain microvessel endothelial cells is inhibited by anti-VLA-4 or its ligand, anti-vascular cell adhesion molecule 1 antibody. 768 92

Transfection of murine metastatic B78H1 cells (derived from B16 melanoma) with a syngeneic H-2Kb gene was used to study the effect of Major Histocompatibility Complex (MHC) gene products on tumour cell adhesion to endothelial cells and matrix proteins and the involvement in the metastatic process. H-2Kb-expressing transfectants showed a reduced adhesion to endothelial surfaces of different origin (four murine endotheliomas and human umbilical vein endothelial cells) when compared to parental B78H1 cells and to controls transfected with pSV2neo alone. On the average a 50-70% reduction in adhesion to endothelial cells was observed among H-2Kb transfectants. H-2Kb transfectants had a reduced expression of the alpha 4 integrin subunit, moreover the adhesion of Neo-transfected clones to endothelial cells was reduced to the levels of H-2Kb transfectants by antibodies directed against the beta 1 subunit and the endothelial VCAM-1 molecule, thus suggesting an impairment of the VLA-4/VCAM-1 interaction in H-2Kb transfectants. Adhesion to extracellular matrix components was also strongly decreased: in general the adhesion of H-2Kb cells showed a 50-75% inhibition with respect to Neo or parental controls. The highest difference was observed in adhesion to vitronectin and laminin, the lowest in adhesion to fibronectin. Reduction in adhesive properties of H-2Kb-expressing transfectants could be involved in the reduced metastatic ability, evaluated by means of intravenous injection of cells: H-2Kb transfectants yielded less than ten lung colonies, while all controls produced more than 100. Our data indicate that expression of a single class I MHC gene can significantly alter the metastatic phenotype of MHC-negative tumour cells and this could be related to a general alteration of tumour cell adhesive interactions.
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PMID:Decreased adhesion to endothelial cells and matrix proteins of H-2Kb gene transfected tumour cells. 769 18

Venous and arterial large vessel endothelial cells (EC) were compared for their constitutive and TNF-alpha-induced expression of the cell-surface adhesion molecules ICAM-1 and -2, VCAM-1 and ELAM-1 by FACS analysis. Human iliac venous and arterial EC (HIVEC and HIAEC) constitutively express ICAM-1 and ICAM-2. TNF-alpha increases the expression of ICAM-1, but not ICAM-2, and induces the expression of ELAM-1 on both EC types. However, TNF-alpha induces VCAM-1 cell-surface expression and mRNA only in venous, but not in arterial EC. We next investigated the function of these adhesion molecules and their ligands, LFA-1, very late activation Ag (WLA-L) and sialylated Lewis x glycoprotein (sLe(x)), in adhesion assays with the monocyte-like cell line U937. Untreated U937 cells do not adhere to untreated HIVEC or HIAEC and adhesion is much lower to TNF-alpha-treated arterial than to TNF-alpha-treated venous EC. In adhesion-inhibition assays we demonstrate that U937 cell adhesion to TNF-alpha-treated HIVEC is mediated by VCAM-1/VLA-4 and ELAM-1/sLe(x) interaction, whereas the lower adhesion to TNF-alpha-treated HIAEC is only mediated by ELAM-1/sLe(x) interaction. U937 cells treated with the phorbol ester PMA for 3 days adhere to both HIVEC and HIAEC; this adhesion is mediated by LFA-1 interaction with ICAM-1 and/or -2. Adhesion of PMA-treated U937 cells is increased by TNF-alpha treatment of EC. This increased adhesion is mediated in part by the TNF-alpha-induced VCAM-1 expression on venous EC. Therefore, the cell-surface adhesion molecule VCAM-1 is differentially induced on these two EC types and the differential expression is functionally important in U937 cell adhesion.
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PMID:Differential induction of VCAM-1 on human iliac venous and arterial endothelial cells and its role in adhesion. 769 6


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