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Query: UNIPROT:P10145 (
IL-8
)
23,849
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
1. The intradermal administration of endothelial
IL-8
(
IL-8(1-77)
or monocyte derived
IL-8
(
IL-8
(1-72) to rabbits produced a concentration-dependent increase in plasma extravasation and an accumulation of polymorphonuclear leukocytes (PMNs) when measured over a 3 h time period. When plasma extravasation and PMN accumulation were measured over a 30 min time period no significant increases in PMN accumulation or plasma extravasation were observed in response to
IL-8
alone. However, under these conditions, the addition of prostaglandin E2 (100 pmol) produced a significant potentiation of
IL-8
-induced plasma extravasation. There was no significant difference between the biological activities of
IL-8(1-77)
and
IL-8
(1-72). 2. Plasma extravasation and PMN accumulation induced by
IL-8
were inhibited in rabbits pretreated with the monoclonal antibody designated IB4 (1 mg kg-1, i.v.) directed against the common beta chain (
CD18
) of the leukocyte integrins. 3. The intra-articular administration to rabbits of
IL-8(1-77)
(1 nmol) resulted 24 h later in the appearance of a mixed population of leukocytes (PMNs and mononuclear cells) in synovial lavage fluid. Biochemical analyses revealed the presence of an increased level of sulphated proteoglycans (sPG) and of the metalloproteinase stromelysin. Pretreatment of rabbits with IB4 (3 mg kg-1, i.v.) inhibited the accumulation of PMNs but had no effect on the mononuclear infiltrate nor on the levels of sPG or stromelysin. 4. The intradermal or intra-articular injection of E. coli-derived endotoxin induced similar inflammatory changes to those observed with
IL-8
.The possibility that the biological activities of
IL-8
were attributable to minor contamination with endotoxin is unlikely for two reasons. Firstly, biological effects of endotoxin were observed at levels greater than that contained in the
IL-8
preparation. Secondly,reduction of the endotoxin content of the
IL-8
preparation by a factor of 10 did not produce a concomitant reduction in the observed biological activity of the
IL-8
.
...
PMID:The role of CD18 in IL-8 induced dermal and synovial inflammation. 135 57
The present study demonstrates that tumour necrosis factor (TNF) and FMLP, but not IL-1 or
IL-8
, enhanced the adherence of polymorphonuclear neutrophil (PMN) to fibronectin, an extracellular matrix protein. The adherence induced by FMLP was very rapid, within 5 min while the induction of adherence by TNF was much slower, reaching maximum at 60 min. TNF also enhanced an adhesion of PMN to other extracellular matrix proteins, such as laminin, collagen IV and gelatin II, but not to human serum albumin. Anti-
CD18
MoAb completely inhibited the binding of TNF-stimulated PMN to fibronectin and partially inhibited the binding to laminin. Further investigation showed that adhesion of TNF-stimulated PMN to fibronectin and laminin was inhibited by anti-CD11b MoAb and to a lesser extent by CD11a MoAb. In contrast to TNF-stimulated PMN the binding of unstimulated PMN to fibronectin and laminin was only inhibited by anti-CD11a MoAb. Anti-CD11c had no effect on PMN adherence. These results suggest that unstimulated PMN adhere to extracellular proteins through the CD11a/18, while TNF-stimulated PMN adhere through the CD11b/18. These results suggest that TNF secreted at the site of inflammation may enhance the interaction of PMN with the extravascular environment through the CD11b/18 complex.
...
PMID:Human polymorphonuclear leucocytes stimulated by tumour necrosis factor-alpha show increased adherence to extracellular matrix proteins which is mediated via the CD11b/18 complex. 135 90
We investigated the role of lymphocyte function-associated antigen 1 (LFA-1) in human T cell polarization and migration assay by using monoclonal antibody specific to beta chain (
CD18
) and alpha chain (CD11a). T cell polarization in response to fetal calf serum (FCS) and colchicine was suppressed by the addition of
CD18
and CD11a antibodies. Furthermore, T cell migration in response to lymphocyte chemotactic factor (LCF) and casein was markedly depressed by the addition of
CD18
and CD11a antibodies. Additional studies to evaluate effects of
interleukin 8
(
IL-8
) on polarization and migration of T cells preincubated with
CD18
or CD11a antibody showed that
IL-8
restored the capability of migration of T cells, whereas did not restore polarization activity of such cells. These studies indicate that LFA-1 plays a role in the polarization and migration of T cells and that
IL-8
may positively interfer with LFA-1-adhesion molecules.
...
PMID:Effects of interleukin-8 on suppression of human lymphocyte polarization and migration by anti-LFA-1 antibody. 136 95
Neutrophils from patients suffering from severe congenital neutropenia (SCN), who were receiving recombinant human granulocyte colony-stimulating factor (rhG-CSF), were investigated in order to analyze the previously described decrease in chemotaxis. This study demonstrated the decreased chemotaxis to five well-known chemoattractants, FMLP, C5a,
IL-8
, LTB4 and PAF. To further investigate this impairment of patients' neutrophils, receptors and receptor turnover for chemoattractants were examined using flow cytometry. We found 1) increased FMLP receptor and decreased C5a receptor expression, 2) a normal expression of intracellular FMLP receptors after incubation with PMA, 3) increased loss and decreased re-expression of FMLP receptors after incubation with this peptide, 4) normal expression of adhesion glycoproteins CR3 (CD11b/
CD18
) and LFA1 (CD11a/
CD18
), 5) further signs of in vivo preactivation: high expression of Fc gamma-RI (CD64) and Fc gamma-RII (CD32), decreased expression of Fc gamma-RIII (CD16), increased expression of CD14, and low expression of HLA-DR. These data demonstrate that the decrease of chemotaxis of neutrophils from SCN patients is not due: a) to a decrease in the number of intra- or extracellular FMLP receptors; b) to a decrease of adhesion molecules. However, the decreased chemotaxis could result from an altered FMLP receptor turnover. The relevance of the altered Fc gamma-receptor pattern for the in vivo occurrence of side-effects, e.g. the necrotic vasculitis, of G-CSF treatment is discussed.
...
PMID:Altered function and surface marker expression of neutrophils induced by rhG-CSF treatment in severe congenital neutropenia. 137 Apr 19
We have previously reported that cytokine- or LPS-activated human umbilical vein endothelial cell (HUVEC) monolayers secrete
IL-8
that can act as a neutrophil-selective adhesion inhibitor. In our study we investigated the mechanisms involved in the leukocyte adhesion inhibitory action of
IL-8
. The leukocyte adhesion inhibitory effect appears to be mediated by the action of
IL-8
on the neutrophil, does not involve down-regulation of relevant endothelial adhesion molecules such as endothelial-leukocyte adhesion molecule-1 or intercellular adhesion molecule-1, and is quantitatively similar in different endothelial activation states that are predominantly endothelial-leukocyte adhesion molecule-1 dependent or intercellular adhesion molecule-1 dependent. In addition to inhibiting the attachment of freshly isolated peripheral blood neutrophils to cytokine-activated HUVEC monolayers,
IL-8
also promoted a rapid detachment of tightly adherent neutrophils from activated HUVEC, and abolished neutrophil transendothelial migration. Certain other chemoattractants, including FMLP and C5a, had similar inhibitory actions, indicating
IL-8
was not unique in its ability to inhibit various neutrophil-endothelial interactions. In contrast, two other neutrophil agonists 1-0-alkyl-2-acetyl sn-glycero-3-phosphocholine and granulocyte-macrophage-CSF, which, like
IL-8
, are produced by activated HUVEC, as well as the leukocyte-derived chemoattractant leukotriene B4, exerted minimal inhibitory effects on adhesion. Regardless of their ability to modulate neutrophil-endothelial cell adhesion, all these agents induced altered leukocyte surface expression of functionally important adhesion molecules, including loss of L-selectin (leukocyte adhesion molecule-1, LECAM-1) and increase in CD11b/
CD18
. Thus, although the above agonists have been characterized primarily as chemoattractants, our findings demonstrate that these agents can exert a wide range of modulatory effects on neutrophil-endothelial adhesive interactions.
...
PMID:In vitro inhibitory effect of IL-8 and other chemoattractants on neutrophil-endothelial adhesive interactions. 138 98
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
Several structural homologues of the chemotactic peptide
neutrophil-activating peptide 1
/
IL-8
(
NAP-1
/
IL-8
) were tested for their ability to influence the expression and function of adhesion-promoting receptors on human polymorphonuclear leukocytes (PMN). NAP-2, melanoma growth stimulatory activity, and two forms of
NAP-1
/
IL-8
(ser-
NAP-1
/
IL-8
and ala-
NAP-1
/
IL-8
, consisting of 72 and 77 amino acids, respectively), each caused an increase in the expression of CD11b/
CD18
(CR3) and CR1, which was accompanied by a decrease in the expression of leukocyte adhesion molecule-1 (LAM-1, LECAM-1). The binding activity of CD11b/
CD18
was also enhanced 3- to 10-fold by these peptides, but enhanced function was transient: binding of erythrocytes coated with C3bi reached a maximum by 30 min and declined thereafter. Ser-
NAP-1
/
IL-8
, ala-
NAP-1
/
IL-8
, NAP-2, and melanoma growth stimulatory activity also caused a two- to threefold enhancement of the phagocytosis of IgG-coated erythrocytes (EIgG) by PMN without causing a large increase in the expression of Fc gamma receptors. Enhanced phagocytosis of EIgG appeared to be mediated through CD11b/
CD18
, because F(ab')2 fragments of an antibody directed against
CD18
inhibited
NAP-1
/
IL-8
-stimulated ingestion of EIgG. The four active peptides caused a rapid, transient increase in the amount of F-actin within PMN, indicating that they are capable of influencing the structure of the microfilamentous cytoskeleton, which participates in phagocytosis. Two other
NAP-1
/
IL-8
-related peptides, platelet factor 4 and connective tissue-activating peptide III, were without effect on expression of CD11b/
CD18
, CR1, and LAM-1, binding activity of CD11b/
CD18
, or Fc-mediated phagocytosis, and increased actin polymerization only slightly. Our observations indicate that several members of the
NAP-1
/
IL-8
family of peptides were capable of promoting integrin-mediated adhesion and Fc-mediated phagocytosis, processes important in the recruitment of PMN to sites of inflammation and antimicrobial responses of PMN.
...
PMID:Differential effects of neutrophil-activating peptide 1/IL-8 and its homologues on leukocyte adhesion and phagocytosis. 172 41
The cytokine
NAP-1
/
IL-8
is produced by a variety of different cells in response to inflammatory stimuli and elicits several biological responses from PMN. Experiments presented here demonstrate that PMN exposed to
NAP-1
/
IL-8
expressed increased amounts of CD11b/
CD18
, as well as CD11c/
CD18
and CR1, on their cell surface, while expression of Fc gamma RIII and HLA-A,B,C remained essentially unchanged. Increased CD11b/
CD18
and CD11c/
CD18
appears to correspond with the release of specific granules by
NAP-1
/
IL-8
.
NAP-1
/
IL-8
was also a potent stimulator of several of the binding activities of CD11b/
CD18
. Ligation of EC3bi by CD11b/
CD18
was rapidly enhanced by
NAP-1
/
IL-8
, but phagocytosis of the ligated particles was not induced by the agonist. In addition, enhanced binding of EC3bi was observed in the absence of an increase in receptor expression as shown with PMN cytoplasts.
NAP-1
/
IL-8
promoted additional adhesive interactions between CD11b/
CD18
and the biosynthetic precursor of LPS, lipid IVa, fibrinogen, and endothelial cells, suggesting that
NAP-1
/
IL-8
may promote leukocyte adhesion in vivo that could lead to recruitment of PMN to sites of tissue inflammation.
...
PMID:Neutrophil-activating protein 1/interleukin 8 stimulates the binding activity of the leukocyte adhesion receptor CD11b/CD18 on human neutrophils. 196 19
The role of neutrophil chemoattractant receptors in neutrophil stimulation in vitro is well established, however, the precise mechanisms underlying local neutrophil accumulation at inflammatory sites in vivo have not been defined. A fundamental question that remains open is whether chemoattractants act on the endothelial cell or the neutrophil to initiate the process of neutrophil migration in vivo. To address this question we have investigated whether neutrophil accumulation in vivo can occur if chemoattractant receptor occupancy is uncoupled from neutrophil stimulation. For this purpose we have used pertussis toxin (PT) as the pharmacologic tool. We have investigated the effect of in vitro pretreatment of rabbit neutrophils with PT on their responses in vitro and on their accumulation in vivo. Pretreatment of rabbit neutrophils with PT inhibited FMLP- and C5a-, but not PMA- induced increases in
CD18
expression, neutrophil adherence, and degranulation in vitro. This pretreatment procedure with PT inhibited the accumulation of radiolabeled neutrophils in vivo in response to intradermally injected FMLP, C5a, C5a des Arg, leukotriene B4,
IL-8
, and zymosan in rabbit skin. Further, in contrast to the in vitro results, PT inhibited the PMA-induced 111In-neutrophil accumulation in vivo. Interestingly, pretreatment of neutrophils with PT also inhibited accumulation in response to intradermally injected IL-1, despite the reports that IL-1 lacks neutrophil chemoattractant activity in vitro. Although the experimental techniques used cannot distinguish the different stages of neutrophil migration involved, these results suggest that the accumulation of neutrophils induced by local extravascular chemoattractants in vivo depends on a pertussis toxin-sensitive receptor operated event on the neutrophil itself. Further, PMA and IL-1 may release secondary chemoattractants in vivo.
...
PMID:Evidence that a receptor-operated event on the neutrophil mediates neutrophil accumulation in vivo. Pretreatment of 111In-neutrophils with pertussis toxin in vitro inhibits their accumulation in vivo. 197
Neutrophil activating factor is a polypeptide cytokine released from stimulated mononuclear phagocytes and endothelial cells. We found that neutrophil activating factor induced time- and concentration-dependent binding of human polymorphonuclear leukocytes to endothelial monolayers and subendothelial matrix proteins, via a mechanism that involves altered expression of the leukocyte CD11/
CD18
glycoproteins. Thus, neutrophil activating factor is a third mediator, in addition to platelet-activating factor and endothelial leukocyte adhesion molecule 1, that is synthesized by activated endothelium and that can induce polymorphonuclear leukocyte adhesion to endothelial cells. Because
NAF
is released into the pericellular fluid, it may also stimulate binding of the leukocytes to exposed subendothelial structures at sites of vascular injury.
...
PMID:Neutrophil activating factor (NAF) induces polymorphonuclear leukocyte adherence to endothelial cells and to subendothelial matrix proteins. 266 43
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