Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P10145 (
IL-8
)
23,849
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Whatever initiates inflammation, the final message mediating cellular invasion is chemical. This consideration allows rational development of anti-inflammatory treatments. Two main classes of chemotactic mediator are recognised. Water-soluble peptides, e.g. cytokines derived from macrophages and other cells, play an important integrating part in the early recruitment of neutrophils and mononuclear cells, and in the amplification of immune responses. Lipid-soluble mediators, of which leukotriene B4 is the most highly chemotactic for neutrophils, are important in secondary amplification. In inflammatory bowel disease, we have shown evidence of increased synthesis of cytokines interleukin 1, 6 and 8. These are associated with activation of circulating monocytes in active Crohn's disease, of lamina propria macrophages in relapse of both ulcerative colitis and Crohn's disease, and development of adhesion molecules on
vascular endothelium
. Our studies show that interleukin 6 is selectively increased in Crohn's disease, whilst preliminary findings suggest that enhanced synthesis of
interleukin 8
is particularly characteristic of ulcerative colitis. Patterns of cytokine synthesis may, therefore, be of diagnostic value. They also offer the potential for therapeutic strategies since cytokine antagonists are becoming available. We have also demonstrated increased synthesis of leukotrienes in active inflammatory bowel disease. Since leukotriene B4 is quantitatively the main chemotactic signal in the mucosa in inflammatory bowel disease during relapse, we investigated the therapeutic effect of suppressing leukotriene B4 synthesis by treating patients with fish oil (as Hi-EPA), giving 4.5 g daily of eicosapentaenoic acid. This competes for the 5-lipoxygenase enzymes, inhibiting leukotriene B4 and promoting synthesis of the less chemotactic product, LTB5.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Therapeutic interventions in gastrointestinal disease based on an understanding of inflammatory mediators. 135 43
The mesothelium is a flat epithelial lining of serous cavities that could gate the traffic of molecules and cells between the circulation and these body compartments. The present study was designed to elucidate the capacity of mesothelial cells to express adhesion molecules and chemoattractant cytokines, two fundamental mechanisms of regulation of leukocyte recruitment. Cultured human mesothelial cells express appreciable levels of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), and these were increased by in vitro exposure to tumor necrosis factor (TNF), interferon gamma (IFN-gamma), or TNF and IFN-gamma. Interleukin 1 (IL-1) was a less consistent stimulus for adhesion molecule expression in vitro. Unlike endothelial cells, used as a reference cell population, resting or stimulated mesothelial cells did not express E-selectin and ICAM-2, as assessed by flow cytometry. Analysis of VCAM-1 mRNA by reverse transcriptase and polymerase chain reaction using appropriate primers revealed that mesothelial cells expressed both the seven- and the six-Ig domain transcripts, with predominance of the longer species. Monocytes bound appreciably to "resting" and, to a greater extent, to stimulated mesothelial cells. Monocytes exposed to IFN-gamma and lipopolysaccharide, used as prototypic activation signals, showed increased capacity to bind mesothelial cells. Anti-CD18 monoclonal antibody significantly inhibited binding of monocytes to mesothelial cells, and this blocking effect was amplified by anti-very late antigen 4. Mesothelial cells were able to express the chemotactic cytokines
IL-8
and monocyte chemotactic protein 1 at the mRNA and protein levels. These results indicate that mesothelial cells can express a set of adhesion molecules (ICAM-1 and VCAM-1) overlapping with, but distinct from, that expressed in
vascular endothelium
(ICAM-1, ICAM-2, VCAM-1, E-selectin), and that these are functionally relevant for interacting with mononuclear phagocytes. The regulated expression of adhesion molecules and chemotactic cytokines by mesothelial cells is probably important in inflammatory and immune reactions that involve serous cavities, such as the long-known macrophage appearance and disappearance reactions.
...
PMID:Expression of adhesion molecules and chemotactic cytokines in cultured human mesothelial cells. 138 76
Interleukin-8
(
IL-8
) induces diverse biological responses in neutrophils, including inhibition of adhesion to cytokine-activated endothelium, which we have termed the leukocyte adhesion inhibition (LAI) effect. Pretreatment of neutrophils with cytochalasin B abolished the LAI effect of
IL-8
, suggesting a microfilament-dependent mechanism.
Interleukin-8
induced a rapid increase (less than or equal to 15 s) in the polymerization of actin filaments in human neutrophils that was blocked by pretreatment with cytochalasin B. F-actin depolymerization occurred gradually at a rate inversely proportional to
IL-8
concentration. This temporal pattern of actin polymerization-depolymerization was similar to that induced by other chemotactic factors such as C5a and N-formylmethionyl-leucyl-phenylalanine, which also exhibit a marked LAI effect, but the lipid mediators, leukotriene B4 and platelet-activating factor, lack any significant LAI effect. Scanning confocal microscopy demonstrated that neutrophil actin microfilaments undergo a dramatic rearrangement prior to detachment of the neutrophil from a surface. We suggest that the ability of
IL-8
and certain other leukocyte agonists to regulate the actin polymer network of neutrophils may play an important role in adhesive interactions with the
vascular endothelium
.
...
PMID:Interleukin-8 induces changes in human neutrophil actin conformation and distribution: relationship to inhibition of adhesion to cytokine-activated endothelium. 164 Jan 74
The data presented in this review establish that cultured human endothelial cells have the capacity to present antigens to T cells and to do so in the context of costimulators that lead to effective T cell activation. These activities raise the possibility that venular ECs, at sites of delayed hypersensitivity reactions, could be the primary antigen-presenting cell to circulating memory T cells. This putative role of ECs can explain the rapid rate of initiation of memory responses because ECs are uniquely positioned to have physical access to the pool of circulating memory T cells. Studies also suggest that ECs may present alloantigens to circulating T cells in the context of transplantation, thereby initiating rejection reactions. Nevertheless, we repeat our caveat that these proposed antigen-presenting functions of ECs have not been established in vivo. Cytokine-mediated changes, particularly induction of adhesion molecules and synthesis of lymphocyte-activating cytokines, such as
IL-8
, provide ECs with the potential to recruit memory T cells to inflammatory sites independent of antigen specificity. Although these functions have also not been rigorously shown to occur in vivo, immunocytochemical studies of experimental and pathological tissues provide significant support for this proposal. Similar adhesive and activating functions of ECs may apply to preferential homing of pre-T cells to thymus and naive T cells to lymph node. We conclude by noting that the weight of evidence reviewed here supports the proposal that the
vascular endothelium
be considered an integral part of the in vivo immune system.
...
PMID:Immunologic interactions of T lymphocytes with vascular endothelium. 195 Jul 97
A large number of cytokines are found within foci of inflammation. Two of these cytokines, namely interleukin-1 (IL-1) and tumor necrosis factor (TNF), play a key role in orchestrating the mechanisms responsible for inflammation. These two cytokines induce production by many cells of lipid mediators, proteases, and free radicals, all of which play a direct role in development of the deleterious effects of inflammation. IL-1 and/or TNF exert cytotoxic effects on the
vascular endothelium
, cartilage, bone, muscle, or pancreatic beta-cell islets. Cytokines, including interferon gamma (IFN), IL-3 and granulocyte-macrophage colony-stimulating factor (GM-CSF), amplify the inflammatory response by increasing production of IL-1 and TNF by macrophages. Macrophages also produce other cytokines, such as
IL-8
and macrophage chemoattractant protein-1 (MCP-1), with chemoattractant properties that contribute to draw leucocytes to the site of inflammation. IL-6, produced in large amounts during inflammatory processes, induces the production of acute phase proteins by hepatocytes. IL-1, TNF, IL-11, leukemia inhibitory factor (LIF), and transforming growth factor beta (TGF beta) share this effect. TGF beta also has a number of anti-inflammatory effects. TGF beta, IL-4, and IL-10 inhibit production of IL-1 and TNF. Glucocorticoids also have this effect. Glucocorticoids can be produced as a result of a chain of events initiated by IL-1, TNF, and IL-6 and involving the neuro-endocrine axis. Other substances, such as IL-1 receptor antagonist (IL-1 ra) or soluble forms of the TNF receptors, can specifically inhibit the effects of IL-1 and TNF. Cascade production of cytokines, inhibition, negative feed-back, and synergistic mechanisms are parameters that illustrate the concept of "cytokine network" and aptly characterize the role of these mediators in the mechanisms of inflammation.
...
PMID:[Contribution of cytokines to inflammatory mechanisms]. 750 93
The human interleukin-3 (IL-3) receptor is constitutively expressed on certain hematopoietic cells where it mediates proliferation and differentiation, or functional activation. We have recently found that human umbilical vein endothelial cells (HUVECs) also express IL-3 receptors and that the expression is enhanced by stimulation with the monokine tumor necrosis factor alpha. In this report we show that the lymphokine interferon gamma (IFN gamma) is a powerful stimulator of the IL-3 receptor of HUVECs and that the combination of IL-3 and IFN gamma has a synergistic effect on major histocompatibility complex (MHC) class II expression and on the production of the early-acting hematopoietic cytokines IL-6 and granulocyte colony-stimulating factor (G-CSF). IFN gamma caused a time- and dose-dependent up-regulation of mRNA for both the alpha and beta chains of the IL-3 receptor, with maximal effects occurring 12 to 24 hours after stimulation with IFN gamma at 100 U/mL. Induction of mRNA correlated with protein expression on the cell surface, as judged by monoclonal antibody staining of both receptor chains and by the ability of HUVEC to specifically bind 125I-labeled IL-3 (125I-IL-3). Scatchard analysis of HUVECs stimulated with IFN gamma at 100 U/mL for 24 hours showed approximately 6,300 IL-3 receptors per cell that were of a high affinity class (dissociation constant [kd] = 500 pmol/L) only. The addition of IL-3 to IFN gamma-treated HUVECs strongly enhanced the expression of MHC class II antigen. Importantly, IFN gamma and IL-3 also exhibited a synergistic effect in the induction of the mRNA for G-CSF and IL-6. This was reflected in increased amounts of G-CSF and IL-6 protein in HUVEC supernatants. In contrast, IFN gamma and IL-3 did not stimulate granulocyte-macrophage colony-stimulating factor (GM-CSF) or
IL-8
production in HUVECs. These results show that IFN gamma is a strong stimulator of IL-3 receptor expression in HUVECs and suggest that in vivo T-cell activation, causing the concomitant production of IFN gamma and IL-3, may lead to enhanced endothelial MHC class II expression and to the selective production of early-acting hematopoietic cytokines. Thus, IL-3 could influence immunity and hematopoiesis by acting not only on hematopoietic cells, but also on
vascular endothelium
.
...
PMID:Interferon-gamma upregulates interleukin-3 (IL-3) receptor expression in human endothelial cells and synergizes with IL-3 in stimulating major histocompatibility complex class II expression and cytokine production. 754 Aug 83
Emigration of leukocytes at sites of inflammation is initiated by the selectin family of carbohydrate-binding adhesion molecules. Molecular crossbridges initiate rolling of cells along the
vascular endothelium
where chemokines such as
IL-8
and platelet activating factor (PAF) may be presented to their receptors on the leukocyte surface resulting in cell stimulation. Integrin activation appears to be a requirement for subsequent cell localization and diapedesis into the tissue. Several recent reports have demonstrated that ligation and cross-linking of neutrophil L-selectin results in neutrophil activation, including intracellular calcium release, superoxide production, and induction of mRNA for production of
IL-8
and TNF-alpha. The purpose of this study was to examine whether ligation and cross-linking of L-selectin would specifically result in activation of beta 2-integrin-dependent adhesion. A fluorescence flow cytometric assay was developed that directly measures Mac-1-dependent cell adhesion. Fluorescent latex beads (2-microns diameter) were adsorbed with albumin or fibrinogen and added in excess to human neutrophils in a shear-stirred suspension. Following stimulation the kinetics of bead capture by neutrophils was continuously measured in real time on the flow cytometer. The onset of bead binding was detected in the presence of extremely low concentrations of PAF (10 pM) or formyl peptide (0.2 nM) stimulation. Ligation of L-selectin with whole IgG DREG200 or DREG56 Ab, but not controls (anti-CD44, -CD45, -CD11a), resulted in a significant potentiation of bead binding. Cross-linking F(ab')2 fragments of DREG200 with a goat anti-mouse F(ab')2 secondary Ab also stimulated beta 2-integrin-dependent adhesion in a dose-dependent fashion. A chimeric form of DREG200 expressing gamma 4 or gamma 1 isotypes of human Fc domain also stimulated cell adhesion when cross-linked. Surface expression of CD18 and an activation-dependent epitope, as detected with mAb24, also increased in response to L-selectin cross-linking. Cross-linking L-selectin induced significant adhesion and transmigration of neutrophils across human umbilical vein endothelial cells. We propose that cross-linking of L-selectin results in a cell signal that directly stimulates beta 2-integrin adhesive responses.
...
PMID:L-selectin (CD62L) cross-linking signals neutrophil adhesive functions via the Mac-1 (CD11b/CD18) beta 2-integrin. 754 24
The early phases of airway inflammation include complex interactions between leukocytes,
vascular endothelium
, and inflammatory cytokines. Therefore, we examined tumor necrosis factor-alpha (TNF-alpha)-induced neutrophil migration through polycarbonate filters and human umbilical vein endothelial (HUVE) cells cultured as monolayers on these filters. TNF-alpha induced both dose- and time-dependent migration of neutrophils across both barriers. At 10(-11)-10(-9) M TNF-alpha, neutrophil migration across HUVE monolayers was more than twofold greater than that observed across naked filters. Modified checkerboard experiments indicated that neutrophils crossed naked filters as a chemokinetic rather than chemotactic response. Supernatants of TNF-alpha (10(-9) M)-stimulated HUVE monolayers induced threefold greater migration of neutrophils across naked filters than 10(-9) M TNF-alpha itself, suggesting release of soluble chemotactic factor(s). Pretreatment of HUVE monolayers with actinomycin D inhibited both TNF-alpha-induced production of soluble chemotactic factors and transendothelial neutrophil migration by > 90%. Supernatants from TNF-alpha-treated HUVE cells contained significant concentrations of
interleukin 8
(
IL-8
), and coincubation of these supernatants with anti-
IL-8
decreased supernatant-induced chemotaxis. Finally, coincubation of TNF-alpha with anti-
IL-8
during transmigration experiments nearly completely inhibited the increase in neutrophil migration measured across HUVE monolayers. In contrast, WEB 2086, a platelet-activating factor receptor antagonist, had no effect. Therefore, endothelial cells greatly facilitate TNF-alpha-induced transcellular migration of neutrophils. This facilitation is dependent on TNF-alpha-stimulated production of
IL-8
. These data further support the active role of
vascular endothelium
in recruiting leukocytes to sites of inflammation.
...
PMID:TNF-alpha-induced transendothelial neutrophil migration is IL-8 dependent. 816 94
Interleukin-8
(
IL-8
) elaborated by monocytes and endothelial cells is a cytokine which is responsible for adhesion of leucocytes to
vascular endothelium
and migration of neutrophils into the cerebrospinal fluid (CSF) from the intravascular space. The inflammation in meningitis is elicited by the cytokine release from leucocytes which encounter micro-organisms in the arachnoid or subarachnoid space. In bacterial meningitis, tumour necrosis factor (TNF), IL-1 and IL-6 are produced vigorously, and initiate and augment the inflammation in the central nervous system. In this study, utilizing a quantitative immunometric sandwich enzyme immunoassay, the concentration of
IL-8
was investigated in the CSF of patients with bacterial meningitis, patients with aseptic meningitis, and patients with gastroenteritis who served as controls. The
IL-8
concentration was markedly higher in the CSF of patients with bacterial meningitis (224 +/- 2.57 pg/ml; mean +/- SD) than in the CSF of patients with aseptic meningitis (less than 30 pg/ml). The
IL-8
level in the CSF of patients with aseptic meningitis did not differ from that in the CSF of the patients with gastroenteritis (less than 30 pg/ml). The augmented production of
IL-8
in CSF may account for the inflammation in bacterial meningitis being more severe than that in aseptic meningitis.
...
PMID:Augmented production of interleukin-8 in cerebrospinal fluid in bacterial meningitis. 826 63
Numerous cytokines are present in inflammatory foci. Two of them, interleukin-1 (IL-1) and tumour necrosis factor (TNF), play a major role in coordinating mechanisms which command inflammation. Under their action many cells produce lipidic mediators, proteolytic enzymes or free radicals, all factors that are directly responsible for the noxious effects observed. IL-1 and/or TNF exert cytotoxic activities on
vascular epithelium
, cartilage, bone, muscle or beta cells of pancreatic islets. Such cytokines as interferon gamma (IFN gamma), IL-3 or granulocyte-macrophage colony stimulating factor (GM-CSF) amplify the inflammatory response by increasing the production of IL-1 and TNF by macrophages. GM-CSF also produces other cytokines, such as
IL-8
and the macrophage chemoattractant protein 1 (MCP-1), the chemotactic properties of which participate in the recruitment of leucocytes within the focus of inflammation. IL-6 abounds in inflammatory processes and induces the production by hepatocytes of acute inflammation phase proteins. The same applies to IL-1, TNF, IL-11, the leukaemia inhibitory factor (LIF) or the transforming growth factor beta (TGF beta). The latter also possesses a number of anti-inflammatory activities and, like IL-4 and IL-10, can inhibit IL-1 and TNF production. Glucocorticoids have this potential activity, and they may be produced by a cascade of events initiated by IL-1, TNF and IL-6, involving the neuroendocrine system. The concept of "cytokine network", therefore, perfectly illustrates the participation of these mediators in inflammatory mechanisms.
...
PMID:[Cytokines and inflammation]. 834 24
1
2
3
4
5
6
7
8
9
10
Next >>