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)

Human bone marrow-derived CD34+ cells were analyzed for the expression of the beta 1-family of integrin adhesion molecules. Integrin alpha 4 beta 1 was consistently expressed by greater than 90% of CD34+ cells, including essentially all assayable granulocyte-macrophage colony-forming cells (CFU-GM) and erythroid bursts (BFU-E) as shown by fluorescence-activated cell sorting studies. Adhesion of highly enriched CD34+ cells to cultured allogeneic marrow stromal cells was largely inhibited both by monoclonal antibody to alpha 4 beta 1 and to vascular cell adhesion molecule-1 (VCAM-1), a ligand for alpha 4 beta 1. VCAM-1 was found to be expressed by bone marrow stromal elements in vitro both constitutively at low level and at high levels after treatment with cytokines. Induction of VCAM-1 was cytokine- and time-dependent with maximum levels being obtained after 4 hours of exposure to a combination of interleukin-4 and tumor necrosis factor-alpha. Cytokine-induced stromal cells bound threefold higher numbers of CFU-GM and BFU-E, this increase being abrogated by anti-alpha 4 beta 1 and anti-VCAM-1 antibodies. In addition, the adhesion to stroma of more immature progenitors, the long-term culture initiating cells, also occurred through an alpha 4 beta 1/VCAM-1-dependent mechanism. These studies identify an adhesion mechanism of potential importance in the localization of primitive progenitors within the hematopoietic microenvironment.
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PMID:Vascular cell adhesion molecule-1 expressed by bone marrow stromal cells mediates the binding of hematopoietic progenitor cells. 137 18

The colon carcinoma cell line HT-29 was used to explore the potential of interleukin-4 (IL-4) and tumor necrosis factor alpha (TNF-alpha) to modify integrin expression and adhesive functions of tumor cells in vitro and to examine corresponding metastatic effects in vivo. Preincubation of HT-29 cells with 100 U/ml of IL-4 for 48 h downregulated the surface expression of the integrin subunits alpha 2, alpha 3, beta 1 and beta 4 after 48 h, whereas the alpha 1 subunit was upregulated. In contrast, 100 U/ml to TNF-alpha selectively upmodulated the expression of alpha v. Attachment to fibronectin of cells treated with IL-4 increased twofold (63.5% vs 32.4%). Adhesion to fibronectin (54.0% vs 32.4%) and vitronectin (37.9% vs 16.4%) was elevated in the case of TNF-alpha stimulation. Using an experimental metastasis model, HT-29 cells showed a significant reduction of their lung-colonizing potential in nude mice when preincubated with IL-4 for 48 h before intravenous injection. The decrease also observed for TNF-alpha-treated cells was less pronounced. The data indicate that the cytokines IL-4 and TNF-alpha can act as direct regulators of adhesive mechanisms of tumor cells bearing adequate receptors, thus influencing lung-colony formation.
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PMID:IL-4 and TNF-alpha induce changes in integrin expression and adhesive properties and decrease the lung-colonizing potential of HT-29 colon carcinoma cells. 860 30

Human acute myeloid leukemia (AML) cells adhere to bone marrow fibroblasts (BMF) and extracellular matrix proteins including fibronectin. Adhesion is increased when fibroblast monolayers are exposed to tumor necrosis factor-alpha (TNF) alone and in combination with interferon-gamma (IFN) or interleukin-4 (IL-4). The combination of TNF and IFN caused enhanced AML cell adhesion to treated BMFs, from a mean of 25.0 +/- 4.1% to 36.3 +/- 5.4% (p = 0.0007). Enhanced binding was partially a result of upregulated vascular cell adhesion molecule-1 expression on BMFs. Intercellular adhesion molecule-1 was also upregulated, but did not appear to play a role in the increased binding to cytokine-stimulated BMFs. In contrast to observed adhesion to resting BMFs, AML cells binding to TNF/IFN-stimulated BMFs rely more heavily on the VLA-4 alpha chain (CD49d). In some cases, alpha4 integrin chain antibody was more effective than beta1 antibody in blocking binding, suggesting that a non-beta1 alpha4 integrin, possibly alpha4 beta7, on AML cells may act as a stromal ligand. The addition of alpha4 antibody to beta1 and beta2 antibodies significantly increased the inhibition of AML cells to stimulated BMFs. The myeloid cytokines granulocyte colony stimulating factor, granulocyte-monocyte colony stimulating factor, interleukin-3 and stem cell factor enhanced the adhesion of AML blast cells to BMFs in some cases. The phorbol ester PMA, however, consistently upregulated AML cell-binding to BMFs, the increase being mediated entirely via beta1 and beta2 integrins without altering AML cell integrin expression. Binding of AML cells to marrow stroma can be enhanced by influences on leukemic cell or stroma. Enhanced binding under these conditions occurs via different pathways, illustrating the heterogeneity of mechanisms underlying leukemic cell retention within the bone marrow stroma.
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PMID:Bone marrow fibroblast exposure to the inflammatory cytokines tumor necrosis factor-alpha and interferon-gamma increases adhesion of acute myeloid leukemia cells and alters the adhesive mechanism. 901 13

Mast cells are inflammatory and immunoregulatory cells resident in tissues. They develop from bone marrow-derived progenitor cells that enter the tissue through the blood circulation. The specific localization and migration of mast cells in tissues is dependent on their interaction with extracellular matrix (ECM) proteins. Adhesion of human mast cells isolated from intestinal mucosa and cultured in the presence of stem cell factor (SCF) to ECM proteins is analyzed. It was observed that SCF is a unique cytokine enhancing mast cell adhesion to all tested ECM proteins (fibronectin, laminin, collagen I, III, IV, VI, XIV) up to 5-fold, particularly to fibronectin (54% +/- 12% of mast cells) and to denatured collagens (40% +/- 12% on cyanogen bromide-cleaved peptides of collagen I). Most noteworthy, preculture of mast cells with interleukin-4 (IL-4), in addition to SCF, reduced their potency to adhere to ECM proteins to one third compared to mast cells cultured with SCF alone. Mast cell adhesion was preferentially mediated by beta1 integrins, and most cells expressed the ECM-binding integrins alpha2beta1, alpha3beta1, alpha4beta1, alpha5beta1, and alphaVbeta3. SCF-induced mast cell adhesion was totally blocked by wortmannin and apigenin, indicating an involvement of phosphatidylinositol 3-kinase and mitogen-activated protein kinase, and it was related to an up-regulation of the HUTS-21 beta1 epitope, which is associated with an activated conformation of beta1. In conclusion, these data indicate that SCF induces the adhesion of cultured mast cells to ECM proteins, whereas IL-4 may promote detachment from the ECM.
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PMID:Regulatory effects of stem cell factor and interleukin-4 on adhesion of human mast cells to extracellular matrix proteins. 1180

As the pathophysiologic process of asthma has become better defined, new molecular targets for treating asthma have emerged. Resident airway cells, circulating leukocytes, and various cell-derived mediators and cytokines contribute to the inflammatory events of asthma. New therapeutic approaches to moderate to severe asthma currently in clinical development include antibodies to IgE and interleukin-5, a soluble receptor that would sequester interleukin-4, cytokine and chemokine receptor antagonists, and phosphodiesterase type 4 inhibitors. Adhesion molecules, which are involved in the migration of inflammatory cells into lung tissue, are also important targets for new antiasthma therapies. Because of researchers' focus on specific pathologic processes and molecular targets, the adverse effects of new agents may be minimized. Also, the longer duration of action of some of the new agents allows weekly to monthly dosing, which may well enhance patient compliance.
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PMID:Treating asthma in the new millennium. 1966 33