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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
Epithelia from several sites exhibit inducible secretion of
interleukin 8
(
IL-8
). This study aimed to characterise secretion of
IL-8
by colonic epithelial cells in vitro. Colonic crypt cells were isolated enzymatically from resected colon and the
IL-8
content of culture supernates was measured by ELISA. The rate of secretion of
IL-8
accelerated and levels of
IL-8
transcripts increased appreciably during culture. Exposure to tumour necrosis factor alpha (TNF alpha) failed to increase secretion further. Secretion was not induced by the enzymatic digestion or by serum used in the culture medium but was significantly inhibited by butyrate, by a mean of 23%. Control experiments indicated that colonic crypt cells were the likely source. The secretion of
IL-8
over 24 hours by cells from uninflamed mucosa of patients with ulcerative colitis or
Crohn's disease
was more than twofold that from normal cells, while that from cancer bearing colons was normal. TNF alpha (10 mM) significantly suppressed
IL-8
secretion only in the ulcerative colitis group and the change was different to those in the normal (p = 0.007) and
Crohn's disease
groups (p = 0.012). Cells from inflamed areas secreted more
IL-8
than those from autologous uninflamed areas (p = 0.009) but responses to modulating factors were no different. The induction of
IL-8
secretion by colonic crypt cells in vitro is probably a response to injury associated with isolation and culture. It is suppressed by butyrate and increased in inflammatory bowel disease independently of the presence of mucosal inflammation. Whether epithelial derived
IL-8
plays a part in the pathogenesis of inflammatory bowel disease is not yet clear.
...
PMID:Interleukin 8 secretion by colonic crypt cells in vitro: response to injury suppressed by butyrate and enhanced in inflammatory bowel disease. 748 42
IL-8
is generating increasing interest as a powerful neutrophil chemoattractant and activator. To elucidate the mechanisms of neutrophil infiltration in inflammatory bowel disease, we examined 33 patients with ulcerative colitis (UC), 18 with
Crohn's disease
(CD), eight with some other type of colitis, and 18 normal control subjects for measurement of
IL-8
in homogenates of colonic biopsy specimens. The affected colonic mucosa was found to contain significantly more
IL-8
in patients with active inflammatory bowel disease than in patients with inactive disease (UC, P < 0.001; CD, P < 0.001), in patients with other types of colitis (UC, P < 0.05; CD, P < 0.01), or in normal control subjects (UC, P < 0.001; CD, P < 0.001). Colonic
IL-8
levels correlated significantly with the macroscopic grade of local inflammation, especially in patients with UC (P < 0.001). Colonic
IL-8
levels also correlated well with the neutrophil numbers in mucosal tissue (UC, r = 0.950, P < 0.001; CD, r = 0.940, P < 0.001), and with colonic IL-1 beta (r = 0.911, P < 0.001) and tumour necrosis factor-alpha (TNF-alpha) levels (r = 0.604, P < 0.001) in patients with these two conditions. These data suggest a potential role for
IL-8
and its regulatory cytokines IL-1 and TNF-alpha in mediating neutrophil infiltration of the gut wall in inflammatory bowel disease.
...
PMID:IL-8 as an important chemoattractant for neutrophils in ulcerative colitis and Crohn's disease. 800 12
Interleukin-8
(
IL-8
) is a potent cytokine for recruitment and activation of neutrophils. To visualize its distribution in the intestinal mucosa and to understand better its possible role in the induction and promotion of inflammatory bowel disease, expression of the
IL-8
gene was analyzed in resected bowel segments of 14 patients with active
Crohn's disease
or ulcerative colitis. In situ hybridization with
IL-8
anti-sense RNA probes revealed strong and specific signals in the histologically affected mucosa. The number of cells expressing
IL-8
gene correlated with the histological grade of active inflammation. In accordance with the characteristic histological signs of active disease,
IL-8
-expressing cells were diffusely distributed over the entire affected mucosa in patients with ulcerative colitis, whereas in patients with
Crohn's disease
,
IL-8
-expressing cells showed a focal distribution pattern. Cells expressing
IL-8
were mainly located at the base of ulcers, in inflammatory exudates on mucosal surfaces, in crypt abscesses, and at the border of fistulae. Analysis of semi-serial sections pointed to macrophages, neutrophils, and epithelial cells as possible sources of this cytokine in active inflammatory bowel disease. We consistently failed to detect
IL-8
messenger RNA in the mucosa of uninvolved bowel segments and in normal-appearing control mucosa of patients with colon cancer. In contrast, tissue specimens from two patients with acute appendicitis displayed
IL-8
-expressing cells in the mucosa. These results support the notion that
IL-8
plays and important but nonspecific role in the pathogenesis of inflammatory bowel disease and that the production of
IL-8
messenger RNA is restricted to areas with histological signs of inflammatory activity and mucosal destruction.
...
PMID:Expression of interleukin-8 gene in inflammatory bowel disease is related to the histological grade of active inflammation. 817 48
To investigate the relationship between serum concentrations of interleukin-8 (IL-8) and disease activity in inflammatory bowel disease, serum IL-8 concentrations were measured by enzyme-linked immunosorbent assay (ELISA) in 93 patients.
Interleukin-8
levels were compared with plasma interleukin-6 (IL-6) levels in 80 of these patients.
Interleukin-8
levels were also measured in ten patients with active
Crohn's disease
, before and after treatment with a defined formula polymeric diet. Of these patients, 70 out of 93 IL-8 concentrations were below the detection limit of the assay. Levels were higher in patients with active ulcerative colitis (median < 20 pg/mL, 75th centile value = 190) compared with inactive disease (median and 75th centile value < 20; P < 0.05).
Interleukin-8
concentrations correlated with a combined score for disease severity and extent (P = 0.01). Thirty-eight per cent (8/20) of patients with active
Crohn's disease
also had high levels of IL-8 but there was no significant difference between active and inactive disease. There was no correlation between serum IL-8 and plasma IL-6; on the contrary, very few patients had raised blood levels of both cytokines. In the diet treated group, serum IL-8 fell significantly after treatment (median = 37 pg/mL, range < 20-4615 before treatment, median < 20, range < 20-104 after treatment; P = 0.03). The results suggest that although IL-8 may be involved in the inflammatory process in inflammatory bowel disease, it is a poor marker of disease activity.
...
PMID:Serum interleukin-8 in inflammatory bowel disease. 828 Aug 36
We considered the role of two neutrophil chemotactic agents (interleukin-8 and leukotriene B4) and of myeloperoxidase (a neutrophil-associated enzyme) in the pathologic condition of
Crohn's disease
(CD). Serial biopsy samples were taken at different sites in the colon, washed in 0.02 M phosphate-saline buffer, homogenized, and then sonicated.
Interleukin-8
levels were significantly increased throughout the colonic mucosa (> 300 pg/mg protein) in patients with CD compared with control groups (< 40 pg/mg protein) (p < or = 0.01). A two- to six-fold increase in leukotriene B4 was also found in CD, whereas mucosal levels of myeloperoxidase were unchanged compared with control subjects. This study demonstrates that interleukin-8 and leukotriene B4 may have an immunologic role in the pathologic condition of CD.
...
PMID:Neutrophil-activating peptide (interleukin-8) in colonic mucosa from patients with Crohn's disease. 838 93
To test whether there is a difference in the expression of
interleukin 8
(
IL8
) between
Crohn's disease
and ulcerative colitis and to determine the main site of its synthesis this study analysed
IL8
in mucosal biopsy specimens of patients with
Crohn's disease
and ulcerative colitis by enzyme linked immunosorbent assay (ELISA) and by in situ hybridisation.
IL8
was measured by ELISA in 38 normal control patients, eight inflammatory control patients, 55
Crohn's disease
biopsy specimens (26 patients), and 67 ulcerative colitis biopsy specimens (35 patients).
IL8
mRNA was determined in samples by in situ hybridisation using a specific
IL8
RNA probe.
IL8
protein was significantly increased in macroscopically inflamed specimens of
Crohn's disease
(median 118 pg/specimen, p < 0.0001), ulcerative colitis (median 140 pg/specimen, p < 0.001), and inflammatory controls (median 30 pg/specimen, p = 0.010) compared with normal controls (median 4 pg/specimen).
IL8
was also increased in uninflamed specimens of
Crohn's disease
(median 46 pg/specimen, p < 0.001) but not of ulcerative colitis patients (median 9 pg/specimen, p = 0.3).
IL8
protein in the mucosa correlated significantly with macroscopic inflammation in
Crohn's disease
(r = 0.47, p < 0.001) and in ulcerative colitis (r = 0.60, p < 0.001).
IL8
mRNA was detected by in situ hybridisation in 31 of 55 biopsy specimens (56%) of
Crohn's disease
patients, in 38 of 67 specimens of ulcerative colitis patients (57%), in five of eight inflammatory controls (63%) and in five of 38 normal controls (13%). Mucosal
IL8
mRNA expression correlated with mucosal
IL8
protein (r = 0.46, p < 0.001).
IL8
mRNA was only detected in inflammatory cells of the interstitium but not in mucosal epithelial cells.
IL8
is produced mainly in the lamina propria of the colon in inflammatory bowel disease and correlates with mucosal inflammation.
...
PMID:Increased interleukin 8 expression in the colon mucosa of patients with inflammatory bowel disease. 880 Dec
If one reviews the literature with zeal, it is increasingly apparent that few organs escape recruitment when IBD is chronic or progressive. Insights into mucosal pathophysiology have helped with understanding the more frequent extraintestinal manifestations, but the mechanisms attendant to the development of less common events (e.g. acute pancreatitis, concurrent gluten sensitive enteropathy, or active pulmonary disease) remain either poorly studied or obscure. It is particularly interesting, however, to read reports of abnormal pulmonary function, generally of the obstructive type, correlated to measurements of abnormal intestinal permeability in patients with either active pulmonary sarcoid or pulmonary involvement in
Crohn's disease
. It has been further speculated that similarities in the mucosal immune system of the lung and intestine are responsible for evidence of bronchial hyperreactivity in patients with active IBD. Finally, it is important to recognize that extensions of the inflammatory process are not restricted to the development of organ-based events but may be responsible for some of the most frequent systemic abnormalities detected in IBD patients. It is now also well confirmed that the cytokine environment in IBD can support activated coagulation and, in some clinical situations, overt vascular thrombosis. The cerebrovascular complications of IBD are well recognized and range from peripheral venous thrombosis to central stroke syndromes and pseudotumor cerebri. Reports of focal white matter lesions in the brains of patients with IBD or an increased incidence of polyneuropathy may be other clinical examples of regional microvascular clotting. Microvascular injury appears to be more ubiquitously present, with reports ranging from a speculated primary causative role (e.g., granulomatous vasculitis in the mesenteric circulation) to the utility of nailbed vasospasm, in
Crohn's disease
, as a clinical marker for disease activity. It is also reported that IL-6 suppression of erythropoietin production is a major feature of the chronic anemia seen in active IBD. Moreover, the capacity of peripheral monocytes from active IBD patients to secrete TNF and
IL-8
is reported predictive for the degree of therapeutic response from recombinant erythropoietin. These collected observations constitute another excellent example of the symmetry between basic science and clinical utility. It is from the context of applied basic science that many future therapies will arise. Empiricism will lose much of its appeal as clinical observations will be increasingly translated into cellular language. Already in animal models, elemental diets diminish IL-6-related acute inflammatory injury, and reductions in dietary lipid alter the antigenicity of bacteria. Provocatively, in humans, unconfirmed reports have even associated diet therapy with the resolution of uveitis and pyoderma gangrenosum. It is likely that efforts will also be made to induce oral tolerance if specific triggering proteins are discovered or to alter bowel flora if such an arcane area of investigation becomes resurgent.
...
PMID:Extraintestinal considerations in inflammatory bowel disease. 880 40
Knowledge of the aetiology and pathogenesis of the inflammation in ulcerative colitis and
Crohn's disease
is still insufficient. It is thought that some antigen is the trigger which induces a chain of immune reactions but the origin of this antigen has not so far been elucidated. In theory, an antigen-presenting cell forms a complex with endotoxin-derived peptides as antigen. T-helper lymphocytes recognize this complex, are activated and start to produce cytokines. For inflammatory bowel diseases (IBD) the most important cytokines identified are interleukin 1 (IL-1), interleukin 2 (IL-2), interleukin 6 (IL-6),
interleukin 8
(
IL-8
), gamma-interferon (G-IFN), and tumor necrosis factor-alpha (TNF-alpha). Inhibition of these cytokines can be achieved by administration of cyclosporine, which inhibits the function of T-helper lymphocytes. Orally, intravenously, and locally administered cyclosporine is able to improve the disease activity in ulcerative colitis and
Crohn's disease
, but its use is limited because of side-effects. The novel immunosuppressant FK506 has comparable actions to cyclosporine in regulating cytokine production and may even be more effective than cyclosporine. The receptor antagonist of IL-1 (IL-1ra) competitively binds to the IL-1 receptor located on several lymphocytes. Treatment of animals with IL-1ra has been successful and clinical trials using recombinant IL-1ra are underway in IBD. Antibodies against alphaIL-2r have also been used successfully in animal studies. No experience with this substance has been obtained in man. The use of alpha-interferon seems to be effective in some patients with
Crohn's disease
. CD4 and CD8 molecules on lymphocytes are needed to form the interaction between antigen, antigen-presenting cell, and lymphocytes. Specific monoclonal antibodies against CD4 are successfully used in patients with active ulcerative colitis and
Crohn's disease
. TNF-alpha shares many of the proinflammatory activities of IL-1. In preliminary studies, especially in patients with
Crohn's disease
, the effects of the administration of antibodies to TNA-alpha were excellent.
...
PMID:Selective immunomodulation in patients with inflammatory bowel disease--future therapy or reality? 881 2
Ulcerative colitis (UC) and
Crohn's disease
(CD) are immunologically mediated disorders characterized by a chronic, relapsing inflammatory response. Elevation of several cytokines, with important immunoregulatory and proinflammatory activities have been demonstrated during active inflammatory bowel disease (IBD). These cytokines, including interleukin-1 (IL-1), IL-6,
IL-8
and GM-CSF, may play an important role in the initiation and amplification of the inflammatory response leading to intestinal injury. There is increasing evidence that IL-1 is activated early in the cascade of events leading to inflammation. Therefore, IL-1 has been implicated as a primary target for therapeutic intervention for the treatment of several inflammatory diseases, including IBD. In addition, a mucosal imbalance of intestinal IL-1 and IL-1ra is present in patients with IBD, suggesting that insufficient production of endogenous IL-1ra may contribute to the pathogenesis of chronic gut inflammation. Preliminary studies examining the association between newly described polymorphisms in the IL-1 gene cluster and IBD have provided new insight into the genetic predisposition to UC. This article will review current progress in understanding the role of Il-1 and Il-1ra in IBD, as well as discuss recently described polymorphisms in the Il-1 gene cluster and their association with UC and CD.
...
PMID:Interleukin-1 and interleukin-1 receptor antagonist in inflammatory bowel disease. 889 1
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