Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P10145 (IL-8)
 23,849 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Selective eosinophil recruitment occurs after experimental Ag challenge and in tissue sites of allergic diseases. The mechanisms of selective eosinophil migration are still unknown. In our study, we examined the ability of chemokines to induce transendothelial migration (TEM) of eosinophils in vitro. Among the chemokines tested, only RANTES induced eosinophil TEM. RANTES failed to induce TEM of neutrophils. Interestingly, IL-8 induced neutrophil TEM and had no effect on eosinophil TEM. RANTES-induced TEM was concentration-dependent and was inhibited by Abs directed against the beta 2 integrin CD18. When IL-1-activated endothelial cells were utilized, RANTES-induced TEM also involved the eosinophil beta 1 integrin VLA-4. RANTES did not increase eosinophil adhesion to either resting or IL-1-activated endothelial cells, nor did the chemokine increase CD11b or decrease L-selectin expression. A gradient of RANTES appears to be required for eosinophil TEM. Pre-exposure of eosinophils to IL-5 dramatically potentiated the TEM response to RANTES. These findings suggest that the chemokine RANTES is a potent and selective inducer of eosinophil TEM. Because RANTES appears to be produced in vivo during allergic reactions or in allergic diseases, we speculate that these findings may have some direct relevance to the mechanism of selective eosinophil recruitment in vivo in humans.
 ...
PMID:Eosinophil transendothelial migration induced by cytokines. III. Effect of the chemokine RANTES. 751 42

T cell locomotion within the extracellular matrix may be mediated by cell adhesion molecules. We investigated the expression and function of beta 1- and beta 2-integrins and CD44 on human peripheral CD4+ and CD8+ lymphocytes locomoting in a 3-D type I collagen matrix. Paths of randomly selected T cells were digitized from time-lapse videorecordings and were quantitatively analyzed. After the blocking of CD49b with mAb Gi9, the locomotion of a defined locomotor subset (50% of spontaneously locomoting cells) was inhibited. Anti-CD49d mAb HP2/1 and an activating anti-CD44 mAb (J173), respectively, induced transient recruitment (< 1 h) of previously nonmotile cells (10 to 35%). In contrast to the J173-induced short-term locomotion, hyaluronan incorporated within the matrix promoted locomotion for > 2 h. No significant effects were present for anti-CD49f (GoH3) and -CD11a (25.3) mAbs. After the addition of IL-8 to the matrix, rapid induction of locomotion in 20 to 30% of the cells (control) was evident, which was virtually abolished by anti-alpha 2- and alpha 6-integrin, and -CD11a mAbs. Thus, the locomotion of nonactivated and IL-8-activated T cells may involve different sets of integrins. Using flow cytometry, the development of a CD49b+CD29highCD44lowL-selectinlow T cell phenotype independent of activation markers including CD25, CD27, CD28, VLA-4, and CD45RA- to CD45RO-transition was observed after 4 days in the matrix. The initial development of spontaneous locomotion in the collagen matrix, however, was not accompanied by alterations in CAM surface staining and, therefore, may involve functional CAM activation rather than involving an increase in surface expression.
 ...
PMID:T lymphocyte locomotion in a three-dimensional collagen matrix. Expression and function of cell adhesion molecules. 753 96

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.
 ...
PMID:Chemokines regulate cellular polarization and adhesion receptor redistribution during lymphocyte interaction with endothelium and extracellular matrix. Involvement of cAMP signaling pathway. 759 74

In vivo, natural killer (NK) cells dominate among the early invading cells in allografts and virus-infected tissues, and they are followed later by an influx of T cells. The same sequence of events was seen in our modified Boyden chamber assay. The migration of both CD3+/CD4+ and CD3+/CD8+ cells through fibronectin-coated filters increased after co-culture with NK cells. The migratory response to a soluble factor from NK cells supernatants was predominantly chemotactic rather than chemokinetic. Endogenous NK cells, purified in the presence of human serum albumin, did not induce T cell chemotaxis, but NK cells which were purified in the presence of 10% fetal calf serum (FCS), or which were activated in the absence of FCS with 10(-4) M histamine, with 300 IU/ml interleukin (IL)-2, or with a combination of 10 IU/ml IL-2 and 10 micrograms/ml CD16 monoclonal antibody increased T cell migration by 30-70%. Both the random and chemotactic migration were dependent on fibronectin receptors VLA-4 and VLA-5 on T cells. About 60% of the chemotactic was neutralized by NAP-1/IL-8 polyclonal antibody. Northern blot analysis revealed IL-8 mRNA expression in highly purified, stimulated NK cells; dimeric IL-8 protein secreted by NK cells was detected by immunoblotting, and, in immunofluorescence staining IL-8 was visualized in NK cells. These observations suggest that NK cells, early invaders in the foci of injury, participate in the initiation of a specific immune response by facilitating T cell recruitment.
 ...
PMID:Stimulated natural killer cells secrete factors with chemotactic activity, including NAP-1/IL-8, which supports VLA-4- and VLA-5-mediated migration of T lymphocytes. 780 22

The cutaneous lymphocyte-associated antigen (CLA) is a carbohydrate epitope present on memory/effector T cells that infiltrate inflamed skin. E-selectin is the ligand for CLA and is induced under inflammation on endothelial cells. CLA was originally postulated as a phenotype marker for skin-associated T cells. We studied the specific in vitro response to skin-associated allergens of CLA+ and CLA-CD45RO+ T cells in atopic dermatitis (AD) and contact dermatitis (CD), which represent two well-characterized T cell-mediated cutaneous allergic inflammations. Whereas CLA+ T cells from AD patients preferentially responded to house dust mite (HDM) and CLA+ T cells from nickel CD patients showed an increased response to nickel, CLA-T cells showed very little response in both cases. In contrast, tetanus toxoid, a systemically acting antigen, induced a proliferative response in both CLA+ and CLA- cells. Interestingly the response to HDM in patients with asthma +/- AD was preferentially found in the CLA- subset indicating the involvement of different homing receptors for mucosal tissues. Moreover, CLA+ T cells showed enhanced migration through activated human umbilical vein endothelial cell monolayers compared to CLA- T cells. The CLA binding to E-selectin is initially responsible for the extravasation that also involves VLA-4/VCAM-1 and LFA-1/ICAM-1 interactions. We have recently identified IL-8 as an endothelial cell-derived chemokine and the IL-8 receptor type B which control CLA+ T cell migration. Such a CLA-mediated migration would localize memory/effector T cells that respond to antigens and reach the body through inflamed skin. Our data support the existence of a regionalization of the immune system and in particular of the skin immune system. It may allow an efficient distribution of the immune defense to different sites of the body.
 ...
PMID:Skin-homing T cells in human cutaneous allergic inflammation. 872 46

The effect of inflammatory mediators on the expression of several surface adhesion molecules on the human mast-cell line (HMC)-1 was studied. By flow cytometry, it could be shown that among several surface adhesion molecules (ICAM-1/CD54, VLA-4/CD49d, Mac-1/CD11b, LFA-1/CD11a, LFA-2/CD2, LFA-3/CD58, VCAM-1), only the constitutively expressed immunoglobulin family member intercellular adhesion molecule-1 (ICAM-1) is modulated by proinflammatory cytokines on HMC-1 mast cells. Stimulation with tumor necrosis factor-a (TNF-alpha) and interferon-gamma (IFN-gamma) resulted, in addition to interleukin-(IL-)4, in selective upregulation of ICAM-1 expression. Costimulation of either IL-4 or IFN-gamma with TNF-alpha further increased the ICAM-1 expression as compared to the stimuli alone. In contrast, stem-cell factor (SCF), granulocyte/macrophage colony-stimulating factor (GM-CSF), IL-10, IL-8, monocyte chemotactic and activating factor (MCAF), and the complement split product C5a failed to modulate the expression of any adhesion molecule examined. The levels of cytoplasmic free calcium in HMC-1 mast cells were not altered by cross-linking surface ICAM-1, suggesting linkage of other intracellular signaling pathways. This cytokine-induced upregulation of ICAM-1 expression might reveal a putative regulatory mechanism of mast-cell interaction with effector cells bearing the counterparts of ICAM-1 (CD54), the molecules Mac-1 (CD11b/CD18) and leukosialin (CD43), and the principal ligand LFA-1 (CD11a/CD18).
 ...
PMID:Modulation of intercellular adhesion molecule 1 (ICAM-1) expression on the human mast-cell line (HMC)-1 by inflammatory mediators. 890 94

Neutrophils, or polymorphonuclear leukocytes (PMNLs), migrate through vascular endothelium and in connective tissue during inflammation. In rats with adjuvant arthritis, migration to joints of radiolabeled (111In) blood PMNLs was examined to define the role of specific selectin and integrin adhesion molecules in this process. Based on monoclonal antibody studies, P-selectin was required for normal PMNL migration to the joints. Although E-selectin alone was not essential, it mediated PMNL accumulation when the P-selectin mechanism was blocked. However, 30% to 40% of the PMNL accumulation was L-, P-, and E-selectin-independent. The integrins, LFA-1 and Mac-1 (CD11/CD18), and VLA-4 mediated PMNL migration to arthritic joints. However, 20% to 40% of PMNL accumulation was via CD18- and VLA-4-independent mechanisms. Human PMNL migration in vitro across unstimulated human umbilical vein endothelial cells (HUVEC), induced by C5a or IL-8, was virtually all mediated by the CD18 (beta2) integrins, LFA-1 and Mac-1. PMNL transendothelial migration was partly CD18-independent (35%) when endothelium was activated with cytokines, such as interleukin-1, and a chemotactic gradient, such as C5a, was also present. This CD18-independent migration was partially E-selectin-dependent in vitro. PMNL migration across synovial fibroblasts induced by C5a was mediated by Mac-1, VLA-4, VLA-5, and VLA-6, functioning in concert. However, up to 30% of migration was via mechanisms as yet to be defined. Thus, PMNL transendothelial and extravascular migration involves some shared, and some distinct mechanisms, as well as some yet to be identified. Defining these mechanisms may help develop therapies for controlling PMNL involvement in inflammation in the vascular and extravascular spaces.
 ...
PMID:Adhesion molecules mediating neutrophil migration to arthritis in vivo and across endothelium and connective tissue barriers in vitro. 983 14

Mobilization of hematopoietic stem and progenitor cells from the bone marrow into the circulation by repetitive, daily stimulations with G-CSF alone, or in combination with cyclophosphamide, is increasingly used clinically; however, the mechanism is not fully understood. Moreover, following mobilization stem cells also home back to the bone marrow, suggesting that stem cell release/mobilization and homing are sequential events with physiological roles. Previously, a role for cytokines such as G-CSF and SCF, and adhesion molecules such as VLA-4 and P/E selectins, was determined for stem cell mobilization. Recent results using experimental animal models and samples from clinical mobilization protocols demonstrate major involvement of chemokines such as stromal derived factor-1 (SDF-1) and IL-8, as well as proteolytic enzymes such as elastase, cathepsin G, and various MMPs in the mobilization process. These results will be reviewed together with the central roles of SDF-1 and CXCR4 interactions in G-CSF or G-CSF in combination with cyclophosphamide-induced mobilization. Furthermore, the central role of this chemokine in stem cell homing to the bone marrow as well as retention of undifferentiated cells within this tissue will also be discussed.
 ...
PMID:Current understanding of stem cell mobilization: the roles of chemokines, proteolytic enzymes, adhesion molecules, cytokines, and stromal cells. 1222 88

Circulating B cells enter the CNS as part of normal immune surveillance and in pathologic states, including the common and disabling illness multiple sclerosis. However, little is known about the molecular mechanisms that mediate human B cell interaction with the specialized brain endothelial cells comprising the blood-brain barrier (BBB). We studied the molecular mechanisms that regulate the migration of normal human B cells purified ex vivo, across human adult brain-derived endothelial cells (HBECs). We found that B cells migrated across HBECs more efficiently than T cells from the same individuals. B cell migration was significantly inhibited by blocking Abs to the adhesion molecules ICAM-1 and VLA-4, but not VCAM-1, similar to the results previously reported for T cells. Blockade of the chemokines monocyte chemoattractant protein-1 and IL-8, but not RANTES or IFN-gamma-inducible protein-10, significantly inhibited B cell migration, and these results were correlated with the chemokine receptor expression of B cells measured by flow cytometry and by RNase protection assay. Tissue inhibitor of metalloproteinase-1, a natural inhibitor of matrix metalloproteinases, significantly decreased B cell migration across the HBECs. A comprehensive RT-PCR comparative analysis of all known matrix metalloproteinases and tissue inhibitors of metalloproteinases in human B and T cells revealed distinct profiles of expression of these molecules in the different cell subsets. Our results provide insights into the molecular mechanisms that underlie human B cell migration across the BBB. Furthermore, they identify potential common, and unique, therapeutic targets for limiting CNS B cell infiltration and predict how therapies currently developed to target T cell migration, such as anti-VLA-4 Abs, may impact on B cell trafficking.
 ...
PMID:Determinants of human B cell migration across brain endothelial cells. 1270 26

Poly(ethylene glycol):poly(acrylate) PEG-g-PA co-polymers were made that inhibited nonspecific protein and cellular adhesion. PEG-g-PA co-polymers were then covalently modified with either cell adhesion peptides or fragments of antibodies to monocyte/macrophage integrin receptors (anti-VLA4, anti-beta(1), anti-beta(2), and anti-CD64) known to enhance macrophage adhesion and, perhaps, modulate their activation. Peptides were either directly conjugated to the base material or linked by way of PEO-star tethers. Fragments of the antibody region containing the antigen-binding site (Fab' fragments) were coupled to other PEG-g-PA samples using the sulhydryl end groups on Fab' fragments to amine-bearing PEO stars. Macrophage adhesion rates, phagocytic response (oxidative burst), and cytokine expression were determined for each PEG-g-PA material. Luminol-enhanced chemiluminescence was used as a semiquantitative indication of monocyte-macrophage phagocytic activation (oxidative burst). Macrophage cytokine expression in response to control, base, and modified materials was determined by ELISAs for TNF-alpha, IL-1 beta, IL-6, and IL-8. Tissue culture poly(styrene) (TCPS)-mediated the greatest number of adherent monocyte/macrophage cells relative to PEG-g-PA materials. Both YRGDS and YEILDV peptides, whether directly or indirectly (via StarPEO) conjugated to PEG-g-PA, increased adhesion versus controls. Fab' fragments of all four antibodies also promoted enhanced adhesion versus controls. Fab'StarPEO materials presented two orders of magnitude fewer ligands per surface unit area than peptide star materials (10(8) vs. 10(10)), but were able to adhere similar numbers of cells. For surfaces presenting Fab'(VLA-4) or YEILDV, both of which may both bind to a cell's VLA-4 receptor, the Star:VLA4 surface showed a greater number of adherent monocyte/macrophages. This result suggests that the Fab' had a higher affinity to the cell receptor than a corresponding minimal peptide binding sequence. All materials exhibited low oxidative burst (luminescence counts per minute, LCPM) per cell DNA without the addition of exogenous stimuli (LCPM/DNA < 100). Directly conjugated peptide materials, poly(propylene) (PP), and TCPS showed the lowest levels of LCPM/DNA without the addition of exogenous stimulus (LCPM/DNA < 20). There was no correlation between LCPM/DNA ratios, with and without added LPS stimulus, versus the individual substrates. Monocyte/macrophages adherent to TCPS substrata showed the overall highest stimulatory potential in cytokine expression response to exogenous LPS, followed by PP > PEG-g-PA > StarPEO. Cells adherent to peptide-modified materials and Fab'-modified materials were overall less stimulated. The method of presenting the peptides (i.e., directly or via Star PEO) influenced the level of cytokine secreted by the adherent macrophage.
 ...
PMID:Monocyte/macrophage interactions with base and linear- and star-like PEG-modified PEG-poly(acrylic acid) co-polymers. 1283 32


1 2 Next >>