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)

Keratinocytes are influenced by cytokines released by skin-infiltrating T lymphocytes. IL-17 is produced by activated CD4+ T cells and can stimulate epithelial cells. We investigated whether IL-17 could modulate the cytokine production and cell-surface molecule expression of keratinocytes. The effects of IL-17 were compared with those of IFN-gamma, which is also derived from activated T cells and is a strong stimulator for keratinocytes. IL-17 enhanced the mRNA and protein production of the proinflammatory cytokines IL-6 and IL-8 in a concentration-dependent way, and induced a weak expression of intercellular adhesion molecule (ICAM)-1 and HLA-DR. The production of IL-1alpha and IL-15 was not altered. IFN-gamma augmented the production of IL-6, IL-8, and IL-15 and strongly induced both cell-surface molecules. IL-17 and IFN-gamma showed marked synergism in the stimulation of IL-6 and IL-8 protein secretion and, to a lesser extent, in the induction of ICAM-1 and HLA-DR expression. The majority of the CD4+ and CD8+ T cell clones derived from lesional psoriatic skin expressed IL-17 mRNA, suggesting that skin-infiltrating T cells can produce this cytokine. This IL-17 mRNA expression was detectable in T helper cell type 1 and type 2 and did not correlate with the IFN-gamma or IL-4 production. In addition, IL-17 mRNA is detectable in biopsies from lesional psoriatic skin, but not in nonlesional control biopsies. Our study indicates that IL-17 is a proinflammatory cytokine, which could amplify the development of cutaneous inflammation and may support the maintenance of chronic dermatoses, through stimulation of keratinocytes to augment their secretion of proinflammatory cytokines.
 ...
PMID:Interleukin-17 and interferon-gamma synergize in the enhancement of proinflammatory cytokine production by human keratinocytes. 976 47

Proinflammatory effects induced by the serine protease factor Xa were investigated in HUVEC. Exposure of cells to factor Xa (5-80 nM) concentration dependently stimulated the production of IL-6, IL-8, and monocyte chemotactic protein-1 (MCP-1) and the expression of E-selectin, ICAM-1, and VCAM-1, which was accompanied by polymorphonuclear leukocyte adhesion. The effects of factor Xa were blocked by antithrombin III, but not by the thrombin-specific inhibitor hirudin, suggesting that factor Xa elicits these responses directly and not via thrombin. IL-1alpha and TNF-alpha were not implicated, since neither the IL-1 receptor antagonist nor a TNF-neutralizing Ab could suppress the factor Xa responses. Active site-inhibited factor Xa and factor Xa depleted from gamma-carboxyglutamic acid residues were completely inactive. The effector cell protease receptor-1 (EPR-1) seems not to be involved since anti-EPR-1 Abs failed to inhibit cytokine production. Moreover, neither the factor X peptide Leu83-Leu88, representing the inter-epidermal growth factor sequence in factor Xa that mediates ligand binding to EPR-1, nor the peptide AG1, corresponding to the EPR-1 sequence Ser123-Pro137 implicated in factor Xa binding, inhibited the factor Xa-induced cytokine production. In conclusion, these findings indicate that factor Xa evokes a proinflammatory response in endothelial cells, which requires both its catalytic and gamma-carboxyglutamic acid-containing domain. The receptor system involved in these responses induced by factor Xa remains to be established.
 ...
PMID:Factor Xa induces cytokine production and expression of adhesion molecules by human umbilical vein endothelial cells. 978 Feb 8

The ability of polymorphonuclear leukocytes (PMNs) to modulate endothelial cell (EC) activation was investigated. Adding PMNs to cultured HUVECs resulted in a release of IL-6 (888 +/- 71 pg/ml, a 35-fold increase over release by the two cell types alone) and IL-8 (45.2 +/- 14.5 ng/ml, a 6.4-fold over PMN release alone and a 173-fold increase over EC release alone). In contrast, the release of TNF-alpha, IL-1beta, and platelet-derived growth factor was not affected by the EC-PMN coculture. Neutralizing mAbs to ICAM-1 or beta2 integrins or a physical segregation of PMNs and ECs did not reduce EC stimulation. In contrast, cell-free supernatants of PMNs recapitulated EC activation with an 18-fold up-regulation of EC IL-6 mRNA. The filtration of PMN supernatant or PMN pretreatment with metabolic antagonists or membrane cross-linking agents all suppressed EC activation. By flow cytometry, PMNs released in the supernatant, heterogeneous membrane-derived microparticles containing discrete proteins of 28 to 250 kDa as resolved by SDS-PAGE. PMN microparticle formation was enhanced by inflammatory stimuli, including formyl peptide and phorbol ester, and was time-dependent, reaching a plateau after a 1-h incubation from stimulation. Purified PMN microparticles induced EC IL-6 release in a reaction that was quantitatively indistinguishable from that observed with unfractionated PMN supernatant and unaffected by a neutralizing Ab to soluble IL-6R. These findings demonstrate that membrane microparticles released from stimulated PMNs are competent inflammatory mediators to produce EC activation and cytokine gene induction.
 ...
PMID:Endothelial cell activation by leukocyte microparticles. 978 Feb 16

We hypothesized that blocking the induction of proinflammatory genes associated with endothelial cell (EC) activation, by inhibiting the transcription factor nuclear factor kappaB (NF-kappaB), would prolong survival of vascularized xenografts. Our previous studies have shown that inhibition of NF-kappaB by adenovirus-mediated overexpression of I kappaB alpha suppresses the induction of proinflammatory genes in EC. However, I kappaB alpha sensitizes EC to TNF-alpha-mediated apoptosis, presumably by suppressing the induction of the NF-kappaB-dependent anti-apoptotic genes A20, A1, manganese superoxide dismutase (MnSOD), and cellular inhibitor of apoptosis 2. We report here that adenovirus mediated expression of a dominant negative C-terminal truncation mutant of p65/RelA (p65RHD) inhibits the induction of proinflammatory genes, such as E-selectin, ICAM-1, VCAM-1, IL-8, and inducible nitric oxide synthase, in EC as efficiently as does I kappaB alpha. However, contrary to I kappaB alpha, p65RHD does not sensitize EC to TNF-alpha-mediated apoptosis although both inhibitors suppressed the induction of the anti-apoptotic genes A20, A1, and MnSOD equally well. We present evidence that this difference in sensitization of EC to apoptosis is due to the ability of p65RHD, but not I kappaB alpha, to inhibit the constitutive expression of c-myc, a gene involved in the regulation of TNF-alpha-mediated apoptosis. These data demonstrate that it is possible to block the expression of proinflammatory genes during EC activation by targeting NF-kappaB, without sensitizing EC to apoptosis and establishes the role of c-myc in controlling induction of apoptosis during EC activation. Finally, these data provide the basis for a potential approach to suppress EC activation in vivo in transgenic pigs to be used as donors for xenotransplantation.
 ...
PMID:Adenovirus-mediated expression of a dominant negative mutant of p65/RelA inhibits proinflammatory gene expression in endothelial cells without sensitizing to apoptosis. 979 84

Although they are considered as destructive agents, free radicals can sometimes become useful. Their presence is intimately coupled with the activity of certain hemal oxydases which insert an atom of oxygen into their substrate by a stereospecific radical mecanism. The cytochromes P450 and the enzymes of the eicosanoide metabolism are some examples. The free radicals can act as second cellular messengers, especially to modulate the metabolism of arachidonic acid and the prostaglandin tract or to infer a myorelaxation. They can even play the role of neurotransmitters such as azote monoxyde. The activation of phagocytes, which is an essential event in the inflammatory reaction, integrates these notions at several levels: in the mechanisms of bacterial death, in the spread of the inflammatory reaction and in the alteration of the extra-cellular matrix. The inflammatory reaction is initiated by interactions between vascular endothelium, platelets and leukocytes including signal exchanges, adhesion molecule expression and secretion of chimiotactic mediators. Activation of vascular endothelium is a key event in the initiation of the phenomenon. The cells intervening in the precocious inflammatory phase were tissular mastocytes and platelet-liberating mediators (histamine) and neutrophile cells responsible for vascular injuries induced by oxygen free radicals and nitric oxide. Reactive oxygen intermediates play a critical role, primarily to limit tissue damage and prevent or inhibit infection, secondary to enhancing and prolonging reaction. The monocytes and platelets liberate cytokines early, which appears to be important in activation and production of an inflammatory response. In fact, cytokines, especially TNF alpha and IL-1, induce synthesis and secretion endothelial adhesion molecules such as ICAM-1, VCAM-1 and E-selectin, which have been demonstrated to mediate leukocyte recruitment to sites of inflammation. The cytokines also activate the fibroblasts and endothelial cells that produce, among others, free radicals and other chimiotactic cytokines of which some (IL-8 and related) can induce neutrophil degranulation and stimulate oxidative stress and formation of free radicals. Furthermore, endothelial cells have been shown to make use of a broad repertoire of cytokines including IL-1, IL-6, IL-8, MCP-1 and gro/MGSA, which may be secreted during an inflammatory response and exercise pro-inflammatory functions. Under the influence of the inflammatory mediators, other enzymes are also activated. The inducible isoforms of cyclo-oxygenase (COX-2) and nitric oxide synthase (iNOS) play an important role in inflammatory reactions via the production respectively of prostaglandins and nitric oxide. The induction of cell adhesion molecules (ICAM-1, VCAM-1 and E-selectin), cytokines, acute phase proteins, growth factors, COX-2 and iNOS expression is mediated by the activation of transcriptional factors, especially the nuclear factor kappa B (NF-kappa B). The NF-kappa B system is essentially involved in immediate early expression of various immunoregulatory genes and has been demonstrated to represent an important regulatory system of endothelial activation. The target genes for NF-kappa B comprise a growing list of genes intrinsically linked to a coordinated inflammatory response. The NF-kappa B is a heterodimer composed of two subunits (p65 and p50). In non-stimulated cells, NF-kappa B resides in the cytoplasm as an inactive complex bound to its inhibitor, I kappa B. Upon stimulation with various agents including cytokines, mitogenes, viruses and reactive oxygen intermediates, I kappa B dissociates from the NF-kappa B-I kappa B complex and translocates to the nucleus, binding with high affinity to specific sites in the promoter regions of target genes and stimulating their transcription. In the case of any weakness of this anti-oxidizing defence or any over-production of radical species, a state of oxidative stress occurs. (ABSTRACT TRUNC
 ...
PMID:[Free radicals and antioxidants: physiology, human pathology and therapeutic aspects (part II)]. 980 2

Precise assessment of blood cell kinetics in the pulmonary microcirculation is extremely difficult because pulmonary microvascular architecture contains arterioles, venules and capillaries in an exceedingly intricate and densely convoluted fashion. Conventional epiluminescence microscopy may not be suitable for investigation of blood cell kinetic in the pulmonary microcirculation, in which arterioles, venules and capillary networks are not located in the same plane. To overcome these impediments, we recently developed a real-time confocal laser luminescence microscope with a high-speed analysis component having the capacity to yield confocal-images of rapidly moving cells at a rate of 1,000 frames/sec and at sufficiently high magnification. In the current review, we will first introduce the details of our newly developed observation system constructed with a view to estimation of blood cell dynamics in the intraacinar microcirculation of the lung. Applying this novel method to isolated perfused rat lungs, we will secondly address the issue of whether or not leukocyte-endothelium interactions in the pulmonary microcirculation qualitatively differ from those serving in the systemic microcirculation. We will particularly shed light on possible roles of endothelial ICAM-1, endothelial P-selectin and leukocyte L-selectin in distorting leukocyte kinetics in the intraacinar microvessels under a variety of diseased conditions, including prolonged exposure to a hyperoxic environment inducing a significant upregulation of ICAM-1 as well as P-selectin on the pulmonary microvascular endothelium, and stimulation of leukocytes by an IL-8 analog causing downregulation of leukocyte L-selectin but inverse upregulation of CD18-related integrins.
 ...
PMID:Do adhesion molecules importantly regulate leukocyte kinetics within intraacinar microvessels of the lung? 981 May 5

The microenvironment of secondary lymphoid organs consists of two major populations of cells, the lymphoid cells and a population of stromal cells that contribute to both tissue architecture and function. Interactions of both populations are essential for the development and control of humoral immune responses. In this study, stromal-cell preparations were obtained by a multistage process. This involved culturing 300-400-microm slices of human tonsil for 6-8 days at 25 degrees C, trypsin digestion of the residual explant, followed by CD45-positive-cell depletion using magnetic beads, and a final period of culture for 4 days to remove remaining nonadherent cells. Phenotyping with a panel of monoclonal antibodies revealed that the cells express HLA-DR, CD54 (ICAM-1), CD44, but no CD45 nor a range of other markers for epithelial and endothelial cells. Immunoassays of supernatants from stromal cells revealed that IL-6 was produced constitutively, and its production was increased by treatment with TNF-alpha and IFN-gamma. In contrast IL-1, IL-2, IL-4, IL-7, IL-8, IL-10, IL-12, TNF-alpha, and IFNgamma were not produced. Functional tests showed that these cells express follicular dendritic cell-like properties. Coculturing of tonsilar B cells with stromal cells resulted in enhanced proliferation and also led to increased production of immunoglobulins and IL-6, suggesting crucial signaling between these populations.
 ...
PMID:Tonsil stromal-cell lines expressing FDC-like properties: isolation, characterization, and interaction with B lymphocytes. 981 1

In order to study the inflammatory potential of ozone on the airway tissue, we developed an in vitro model system in which human bronchial epithelial cells (BEAS 2B) and human umbilical vein endothelial cells (ECV304) were able to communicate with each other. The BEAS 2B cells were grown on filter supports which were inserted into six-well culture dishes. Endothelial cells were cultivated on the bottom of the basolateral compartment. The upper epithelial cells were exposed to 0.15 ppm ozone for 90 min. Supernatants were collected after 1, 4 and 24 h and were quantified for IL-6 and IL-8 secretion. At the same time points we measured the expression of ICAM-1 on the umbilical vein endothelial cells. Exposure of the coculture-system to air or ozone induced the production of IL-6 as well as IL-8 that exceeded the sum of the amounts produced by the two cell types when exposed separately. At 24 h after ozone exposure the IL-6 and IL-8 levels were significantly elevated compared with the air treated cells. Concerning the ICAM-1 expression on ECV304 cells we found elevated ICAM-1 levels on cells which had been cocultured with BEAS 2B cells compared with cells cultured alone. This might be a hint for the secretion of a soluble factor that acts as a mediator in amplifying the response of epithelial cells.
 ...
PMID:A new coculture-system of bronchial epithelial and endothelial cells as a model for studying ozone effects on airway tissue. 982 Jun 44

We investigated the effect of TNF alpha, IL-1alpha and IFN gamma on two neuroblastoma (NB) cell lines (SK-N-SH and SK-N-MC). These lines responded differentially to IL-1alpha, TNF alpha and IFN gamma for MCP-1 and IL-8 production and expression of the ICAM-1 and VCAM-1 adhesion molecules. None of the cytokines induced MCP-1 or IL-8 on SK-N-MC cells. Both chemokines were produced in response to IL-1alpha by SK-N-SH cells, while TNF alpha induced mainly MCP-1 production. Addition of IFN gamma decreased IL-8, but not MCP-1 production. These responses correlated with monocyte and neutrophil chemotactic activity in NB culture supernatants. This activity was neutralized by antibodies to IL-8 and MCP-1. The expression of ICAM-1 on SK-N-MC was up-regulated by TNF alpha or IFN gamma, while IL-1alpha also upregulated ICAM-1 on SK-N-SH cells. VCAM-1 expression on SK-N-SH was induced by IL-1alpha and TNF alpha and IFN gamma synergized with TNF alpha in this respect on both NB cell lines. These results suggest that mechanisms for chemokine production and VCAM-1 and ICAM-1 upregulation by inflammatory cytokines differ and IFN gamma, in conjunction with TNF alpha, stimulate neural cell responses (high MCP-1 and VCAM-1 and decreased IL-8) favouring mononuclear cell recruitment.
 ...
PMID:Chemokine production and adhesion molecule expression by neural cells exposed to IL-1, TNF alpha and interferon gamma. 982 72

The homing of lymphocytes to secondary lymphoid organs is thought to involve the action of chemokines. Secondary lymphoid-tissue chemokine (SLC), a high endothelial venule (HEV)-associated chemokine, has emerged as a candidate for participating in this process. We now show that immobilized SLC strongly induces beta2 integrin-mediated binding of T lymphocytes of naive phenotype and B lymphocytes to ICAM-1 under static conditions. This effect is not mediated by beta2 integrin affinity modulation, because SLC does not elicit a beta2 integrin activation epitope (mAb24) on naive T lymphocytes. In a parallel plate flow chamber, lymphocytes rolling via L-selectin are rapidly arrested through beta2 integrins in a pertussis toxin-sensitive manner on a substrate consisting of L-selectin ligands (peripheral lymph node addressins) together with ICAM-1 and SLC. Naive T lymphocytes are arrested on the HEV substrate with sixfold higher efficiency than memory cells. Neutrophils roll, but are not arrested by SLC, whereas they respond to immobilized IL-8 with rapid arrest. Thus, our artificial HEV system recapitulates critical features of lymphocyte interactions with HEV in vivo. These observations strongly point to the participation of SLC in homing of lymphocytes to secondary lymphoid organs.
 ...
PMID:A high endothelial cell-derived chemokine induces rapid, efficient, and subset-selective arrest of rolling T lymphocytes on a reconstituted endothelial substrate. 983 23


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>