Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.59 (MIP)
 4,906 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

CD44 is a cellular adhesion molecule expressed in many different types of cells that may be a receptor for hyaluronic acid, laminin, collagen or fibronectin. In this study, we determined whether CD44 participated in the adhesion of three human colorectal carcinoma cell lines (KM-12c, CCL 188 and MIP-101) to laminin, collagen and hyaluronic acid. All lines were positive for the epithelial form of CD44 (CD44E) with a molecular weight of approximately 160 kD. All of them bound significantly to laminin and type IV collagen but not to hyaluronic acid in a solid phase adhesion assay. Three monoclonal antibodies to CD44 (Hermes 1, Hermes 3 and J173) significantly blocked the binding of colorectal carcinoma lines to laminin and collagen whereas another antibody to CD44 (50B4) bound to cells but did not inhibit adhesion. Only Hermes 1 completely abolished the binding to hyaluronic acid by a human B lymphoblastoid cell line, JY, that expressed the 90 kD haematopoietic form of CD44. Soluble hyaluronate inhibited the adhesion of JY cells to solid phase hyaluronate but did not inhibit adhesion to laminin and collagen by the colorectal carcinoma lines. Thus, (a) CD44E participates in the adhesion of colorectal carcinoma cells to laminin and type IV collagen and (b) the binding site for laminin and collagen on CD44E is different from the site for hyaluronic acid.
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PMID:CD44 participates in the adhesion of human colorectal carcinoma cells to laminin and type IV collagen. 750 63

The mast cell is one of the major effector cells in inflammatory reactions and can be found in most tissues throughout the body. During inflammation, an increase in the number of mast cells can be seen, e.g., in the intraepithelial cell layer after a provoked allergic reaction. Such accumulation probably requires directed migration of mature mast cells or their precursors. To study the migration of human mast cells we used as a model the human mast cell line, HMC-1, and stem cell factor-dependent (also referred to as mast cell growth factor or Kit ligand) cord blood-derived mast cells. The results show that stem cell factor is a potent chemotactic factor for human mast cells in vitro. The chemotactic response to SCF was found to be dose dependent, reaching a maximum at 50 ng/ml. The activity of SCF could be blocked by anti-SCF Abs. We also tested the effect of different intercrines, i.e., IL-8, MIP-1 alpha, MIP-1 beta, RANTES, and MCAF (also referred to as monocyte chemotactic protein 1), on human mast cell migration. Only RANTES was chemotactic for in vitro-developed mast cells. None of the tested intercrines induced migration of HMC-1 cells. For migration, the mast cells were dependent on binding to an extracellular matrix protein. Thus, coating of the filters with fibronectin was required, whereas collagen or laminin did not promote migration. Adhesion of HMC-1 cells to fibronectin could also be shown in an adhesion assay. In addition, expression of receptors for fibronectin could be detected on the surface of the mast cells. These results show that SCF is not only a growth and differentiation factor for human mast cells in vitro but also a potent chemoattractant for such cells.
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PMID:Stem cell factor is a chemotactic factor for human mast cells. 752 4

The present report compares a variety of T cell purification protocols and chemotaxis procedures in assessing chemokine-induced T cell migration using a microchemotaxis assay. Rapidly purified T cells are capable of directly responding to the beta chemokines macrophage inflammatory protein-1 alpha (MIP-1 alpha), MIP-1 beta, and RANTES in the absence of alpha CD3 stimulation as previously described (Taub, D.D. and Oppenheim, J.J. (1993) Cytokine 5, 175). However, T cell purification schemes involving prolonged 37 degrees C incubations generally produce non-motile T lymphocytes that require stimulation with alpha CD3 antibody for 6-12 h in culture to recover chemotactic mobility. This loss of chemotactic potential appears to be due to prolonged 37 degrees C incubations as rapidly purified T cells lose migratory activity upon incubation at 37 degrees C. Radiolabeled binding analysis revealed that beta chemokine binding sites are downregulated as short as 2 h after incubation at 37 degrees C. T cells require the presence of extracellular matrix molecules to facilitate T cell migration. While many of these proteins permit chemotactic activity, human plasma and foreskin fibronectin were found to be the most effective matrix molecule for T cell migration. Kinetic analysis of T cell activation revealed that 6-12 h of anti-CD3 stimulation was optimal to restore the ability of purified T cells to migrate in response to the chemokines MIP-1 alpha, MIP-1 beta, RANTES, and IL-8. However, rapidly dividing T cells (> or = 48 h post alpha CD3 mAb stimulation) fail to migrate in response to any chemotactic stimulus. Together, these results suggest that the measurement of T cell migration, using microchemotaxis chambers, is a multifactorial process with strict environmental and activation requirements.
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PMID:Chemotaxis of T lymphocytes on extracellular matrix proteins. Analysis of the in vitro method to quantitate chemotaxis of human T cells. 754 17

The extravasation of leukocytes from the lumen of the vessel to a site of inflammation requires specific binding events. The interaction of leukocytes with endothelium, via specific receptors, may provide intracellular signals that activate extravasating cells. In the present study, we have investigated the production of chemokines, interleukin-8 (IL-8), and monocyte chemoattractant protein-1 (MCP-1) during monocyte: endothelial cell interactions. Both unstimulated and interferon-gamma (IFN-gamma)-prestimulated human umbilical vein endothelial cells (HUVEC) produced low constitutive levels of IL-8 and MCP-1. The addition of enriched monocytes with unstimulated HUVEC resulted in synergistic increases in production of both IL-8 and MCP-1. Monocytes cultured with IFN-gamma-preactivated HUVECs demonstrated little additional increase in IL-8 and MCP-1 production in coculture assays compared with unstimulated HUVEC. Northern blot analysis paralleled the protein data, demonstrating upregulated expression of IL-8 and MCP-1 mRNA in stimulated and unstimulated coculture assays. Culture of enriched monocytes and endothelial cells in transwells demonstrated no increases in IL-8 or MCP-1, indicating the necessity for cellular contact for chemokine production. In previous investigations, we have demonstrated that increased monocyte-derived MIP-1 alpha production was induced by intracellular adhesion molecule-1 (ICAM-1) interactions on activated HUVECs. In contrast, addition of anti-ICAM-1 monoclonal antibodies (MoAbs) did not diminish the production of IL-8 and MCP-1 in the present study. Furthermore, neither antibodies to IL-1 nor tumor necrosis factor (TNF) diminished the production of either IL-8 or MCP-1. However, when soluble matrix proteins were added to the coculture to block cellular interactions, the chemokine protein and mRNA levels were significantly decreased. IL-8 production was decreased by both soluble collagen and fibronectin, whereas MCP-1 was decreased by only soluble collagen, suggesting differential activation pathways. These results indicate that IL-8 and MCP-1 production are increased during monocyte and endothelial cell interactions in part due to matrix protein binding mechanisms. This mechanism may serve a role in cell activation, production of chemokines, as well as extravasation and recruitment of additional leukocytes during inflammatory responses.
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PMID:Production of chemokines, interleukin-8 and monocyte chemoattractant protein-1, during monocyte: endothelial cell interactions. 754 70

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

Leukocyte recruitment is a key step in the inflammatory reaction. Several changes in the cell morphology take place during lymphocyte activation and migration: spheric-shaped resting T cells become polarized during activation, developing a well defined cytoplasmic projection designated as cellular uropod. We found that the chemotactic and proinflammatory chemokines RANTES, MCP-1, and, to a lower extent, MIP-1 alpha, MIP-1 beta, and IL-8, were able to induce uropod formation and ICAM-3 redistribution in T lymphoblasts adhered to ICAM-1 or VCAM-1. A similar chemokine-mediated effect was observed during T cells binding to the fibronectin fragments of 38- and 80-kD, that contain the binding sites for the integrins VLA-4 and VLA-5, respectively. The uropod structure concentrated the ICAM-3 adhesion molecule (a ligand for LFA-1), and emerged to the outer milieu from the area of contact between lymphocyte and protein ligands. In addition, we found that other adhesion molecules such as ICAM-1, CD43, and CD44, also redistributed to the lymphocyte uropod upon RANTES stimulation, whereas a wide number of other cell surface receptors did not redistribute. Chemokines displayed a selective effect among different T cell subsets; MIP-1 beta had more potent action on CD8+ T cells and tumor infiltrating lymphocytes (TIL), whereas RANTES and MIP-1 alpha targeted selectively CD4+ T cells. We have also examined the involvement of cAMP signaling pathway in uropod formation. Interestingly, several cAMP agonists were able to induce uropod formation and ICAM-3 redistribution, whereas H-89, a specific inhibitor of the cAMP-dependent protein kinase, abrogated the chemokine-mediated uropod formation, thus pointing out a role for cAMP-dependent signaling in the development of this cytoplasmic projection. Since the lymphocyte uropod induced by chemokines was completely abrogated by Bordetella pertussis toxin, the formation of this membrane projection appears to be dependent on G proteins signaling pathways. In addition, the involvement of myosin-based cytoskeleton in uropod formation and ICAM-3 redistribution in response to chemokines was suggested by the prevention of this phenomenon with the myosin-disrupting agent butanedione monoxime. Interestingly, this agent also inhibited the ICAM-3-mediated cell aggregation, but not the cell adhesion to substrata. Altogether, these results demonstrate that uropod formation and adhesion receptor redistribution is a novel function mediated by chemokines; this phenomenon may represent a mechanism that significantly contributes to the recruitment of circulating leukocytes to inflammatory foci.
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PMID:Chemokines regulate cellular polarization and adhesion receptor redistribution during lymphocyte interaction with endothelium and extracellular matrix. Involvement of cAMP signaling pathway. 759 74

Epidemiologic studies have linked diets high in animal fat with colon carcinogenesis. A number of animal tumor models have shown that diets rich in omega-3 fatty acids inhibit colon carcinogenesis while diets rich in omega-6 fatty acids promote tumor growth. This study examines whether modification of the membrane fatty acid composition of both moderately (CX-1) and poorly differentiated (MIP-101 and Clone A) human colorectal carcinoma cells alters their interaction with Kupffer cells and extracellular matrix proteins (collagen type IV, fibronectin and laminin). The cells were treated with 15-16 micrograms/ml of docosahexanoic acid (22:6, omega 3) or linoleic acid (18:2,omega 6). Gas chromatography showed significant alterations in the membrane fatty acid composition of the human colorectal cancer cell lines. Binding assays were performed by measuring adherence of 51Cr-labelled tumor cells to Kupffer cell monolayers or to immobilized proteins. Omega-3 treatment significantly decreased the Kupffer cell binding of only the CX-1 line while omega-6 treatment decreased binding of all three cell lines. In contrast both omega-3 and omega-6 treatment of MIP-101 cells decreased binding to the extracellular matrix proteins with the omega-6 effect being more pronounced. These results indicate that the binding characteristics of the colon cancer cells to both Kupffer cells and extracellular matrix proteins may be determined in part by the membrane fatty acid composition. Decreased adherence to extracellular matrix proteins may lead to increased cell motility and invasiveness. Since Kupffer cell binding precedes tumor cell phagocytosis and killing, decreased binding may improve tumor cell survival.
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PMID:Effect of membrane free fatty acid alterations on the adhesion of human colorectal carcinoma cells to liver macrophages and extracellular matrix proteins. 788 22

Cell surface hypersialylation of human colorectal carcinoma (HCRC) cells correlates with increased metastatic potential after intrasplenic injection, while desialylation with various agents has been shown to inhibit hepatic metastases. In this study we examined the effects of desialylation of HCRC cell lines with a novel intracellular inhibitor of the CMP-sialic acid transport protein (KI-8110). HCRC cells, which are poorly differentiated and poorly metastatic in nude mice (Clone A and MIP-101) were compared to well-differentiated, highly metastatic cells (CX-1 and CCL-235). KI-8110 treatment has previously been shown to reduce sialic acid levels in each of these cell lines and to reduce hepatic metastases in CX-1 and CCL-235 cell lines. This study attempts to identify a mechanism by which desialylation inhibits hepatic metastases. After KI-8110 treatment, in vitro adhesion assays were performed with each cell line to examine binding to Kupffer cells and the extracellular matrix protein fibronectin. Binding of Clone A, CX-1, and CCL-235 to Kupffer cells was significantly increased after KI-8110 treatment. Desialylation had no significant effect on binding of HCRC cell lines to fibronectin. While the metastatic cascade involves many complex interactions, the cytotoxic effects of Kupffer cells in the hepatic sinusoid are known to be an important mechanism of host defense against tumor cells. Cell surface sialic acids may well mask Kupffer cell binding to HCRC cells, preventing their cytotoxic effects and enhancing the metastatic potential of circulating tumor cells.
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PMID:Desialylation of metastatic human colorectal carcinoma cells facilitates binding to Kupffer cells. 830 24

The ability of chemokines, particularly MCP-1, to induce integrin-dependent binding of T lymphocytes to endothelial adhesion molecules or extracellular matrix (ECM) components was examined. MCP-1 induced significant adhesion to fibronectin (FN) and to endothelial-secreted ECM but not to purified ICAM-1 or VCAM-1, or to activated endothelium. The MCP-1-induced binding of T lymphocytes to FN was rapid, dose dependent, and resulted from activation of both VLA-4 and VLA-5. Like MCP-1, the chemokines RANTES and MIP-1 beta induced T lymphocyte binding to FN, but not to ICAM-1. We suggest therefore, that these T lymphocyte chemokines may be most important, not in initiating integrin-dependent firm adhesion of T lymphocytes to the vascular wall, but rather, in subsequent adhesive interactions during migration into tissue.
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PMID:The C-C chemokine MCP-1 differentially modulates the avidity of beta 1 and beta 2 integrins on T lymphocytes. 862 8

The increased migration of peripheral blood mononuclear cells (PBMNCs) across a fibronectin (FN) matrix in response to the chemokines RANTES, MIP-1 alpha and MCP-1 is antagonized by interferon-beta-1b (IFN beta-1b). MCP-1 treatment of PBMNCs elevates their mRNA level and secretion of a matrix degrading enzyme, matrix metalloproteinase (MMP)-9, which is abrogated by IFN beta-1b. The clinical benefits of IFN beta-1b treatment in multiple sclerosis patients may in part be a result of this drug's ability to decrease the migration of PBMNCs in spite of a chemotactic gradient. Furthermore, the elevation of MMP-9 production by PBMNCs may be an important mechanism of action of chemokines.
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PMID:Chemokine-enhanced migration of human peripheral blood mononuclear cells is antagonized by interferon beta-1b through an effect on matrix metalloproteinase-9. 941 58


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