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

Neutrophils elicited in the peritoneal cavity of guinea pigs were purified on Percoll gradients and their chemotactic response to hrIL-8 and fMLP measured in vitro. hrIL-8 and fMLP were effective chemoattractants with optimal concentrations of 6 x 10(-9) and 1 x 10(-7) M, respectively. Scatchard analysis revealed approximately 205,000 IL-8 receptors/cell and 34,000 fMLP receptors/cell with KD values of 4.1 x 10(-9) and 3.3 x 10(-8) M, respectively. At suboptimal concentrations of chemoattractants the response was inhibited by dibutyryl cyclic AMP, histamine, and adenosine in the presence of a phosphodiesterase inhibitor. IL-8 and fMLP induced an increase in cellular cyclic AMP and the response to optimal concentrations of chemoattractants was inhibited by Calphostin C and Ro 31-8220, inhibitors of protein kinase C (PKC). Our results indicate that the chemoattractants activate the same PKC-dependent pathway that is down-regulated by cyclic AMP-dependent mechanisms.
J Leukoc Biol 1994 Dec
PMID:Modulation of the chemotactic responsiveness of guinea pig neutrophils to hrIL-8 and fMLP. 799 52

Neuroblastoma cells in response to retinoic acid (RA) exhibit differentiation. RA, which can promote tumor cell differentiation, has also been shown to regulate tumor-infiltrating leukocytes. In an attempt to explore the relationship between RA-induced neuroblastoma cell differentiation and leukocyte chemotaxis, we investigated expression of IL-1 beta, IL-8, granulocyte-macrophage colony stimulating factor, and tumor necrosis factor-alpha in the undifferentiated and RA-induced differentiated neuroblastoma cells. Using SK-N-SH neuroblastoma cells, we found that RA induced differentiation of SK-N-SH cells as demonstrated by down-regulation of N-myc gene expression, cell-cycle arrest in G1 phase, and phenotypic change. Neither RA-treated nor untreated neuroblastoma cells expressed IL-1 beta, granulocyte-macrophage colony stimulating factor, or tumor necrosis factor-alpha mRNA. RA-treated but not untreated SK-N-SH cells expressed IL-8 mRNA in a time- and dose-dependent fashion. As determined by ELISA, IL-8 levels were detectable in the culture supernatants from RA-treated, but not untreated, neuroblastoma cells (2.65 +/- 0.43 versus 0.05 +/- 0.04 ng/mL). Using neutrophil and lymphocyte chemotactic assays, we found that RA-treated but not untreated culture supernatants of neuroblastoma cells promoted neutrophil and lymphocyte chemotaxis. The RA enhancement of neuroblastoma cell-mediated leukocyte chemotaxis was significantly blocked by anti-IL-8 neutralizing antibodies. These results suggest that RA-induced neuroblastoma cell differentiation is associated with production of functional IL-8, which may be involved in the leukocyte infiltration and activation resulting in tumor regression.
Pediatr Res 1993 Dec
PMID:Induction of interleukin-8 expression in neuroblastoma cells by retinoic acid: implication of leukocyte chemotaxis and activation. 810 82

Acute or chronic exposure to cadmium (Cd) causes severe organ damages with the infiltration of leukocytes, neutrophils in particular occurring in the acute phase. Interleukin-8 (IL-8), a novel neutrophil chemotactic and activating cytokine, is produced by various types of cells in response to a wide variety of inflammatory stimuli. The administration of an antibody against IL-8 has been shown to inhibit neutrophil infiltration in several animal models, indicating a causal relationship between IL-8 and neutrophil infiltration. Hence, in this study we investigated whether Cd induced IL-8 production in human peripheral blood mononuclear cells (PBMC). Cd, over a wide range of concentrations, did induce human PBMC to produce large amounts of bioactive IL-8, the maximal induction being observed at 10(-4) M. The production was inhibited specifically by a metal chelating agent, ethylenediaminetetraacetic acid (EDTA). Steady level of IL-8 mRNA increased within 30 min after the addition of Cd and reached a maximal level at 2 h, decreasing thereafter. A protein synthesis inhibitor, cycloheximide, failed to inhibit IL-8 mRNA accumulation, indicating that new protein synthesis was not required for IL-8 mRNA induction. Concomitantly with the induction of IL-8, within 10 min Cd generated reactive oxygen intermediates (ROI) in human PBMC. A radical scavenger, N-acetyl-L-cysteine (NAC), inhibited both IL-8 production and the generation of ROI, implying the possible involvement of ROI in IL-8 production. This notion was also supported by our findings that a superoxide generating agent, paraquat, induced IL-8 production in human PBMC and that NAC blocked this paraquat-induced IL-8 production.
Lymphokine Cytokine Res 1993 Dec
PMID:Cadmium induces interleukin-8 production in human peripheral blood mononuclear cells with the concomitant generation of superoxide radicals. 812 58

Hematopoiesis is regulated by colony-stimulating factors (CSF) and many other cytokines. T helper cell and monocyte/macrophage interactions that take place in the immune response, resulting in the production of many cytokines, probably can influence inducible hematopoiesis. We investigated the effect of the T helper cell-derived lymphokines IL-2, IL-3, GM-CSF, and IFN-gamma, on the expression of cytokine genes in monocytes and compared this to LPS-induced cytokine gene expression in monocytes. To avoid inadvertent activation of monocytes, cells were purified by elutriation and cultured under serum-free, LPS-free, and nonadherent conditions. Similar to LPS, IL-2, IL-3, and GM-CSF induced the expression of IL-1 beta, IL-6, IL-8, TNF-alpha, and IL-1-RA genes in monocytes, but with some differences in the amount and kinetics of cytokine mRNA accumulation. Unlike LPS, IL-2, IL-3, and GM-CSF did not induce G-CSF and GM-CSF gene expression in monocytes. GM-CSF and IL-3 were the only inducers capable of expressing the M-CSF gene in monocytes. IL-2, IL-3, and GM-CSF showed no effect on the IL-10 gene while IFN-gamma appeared to have no effect on any of the cytokine genes studied in monocytes. These data indicate that in the immune response expression of the proinflammatory cytokine genes, IL-1 beta, IL-6, IL-8, and TNF-alpha, can occur and that autoregulatory control mechanisms, like the expression of IL-1-RA gene, are also activated.(ABSTRACT TRUNCATED AT 250 WORDS)
Lymphokine Cytokine Res 1993 Dec
PMID:Regulatory effects of T cell lymphokines on cytokine gene expression in monocytes. 812 62

IL-8 was measured in knee joint synovial fluid of 60 patients with rheumatoid arthritis, 8 with gout, 6 with osteoarthritis and 4 with meniscus lesions. IL-8 could be demonstrated in most SF samples. The highest levels were observed in rheumatoid joint effusions, yet mean levels were not significantly different between the different subgroups (mean +/- SE; RA 1537 +/- 3049 pg/ml, gout 570 +/- 952 pg/ml, OA/ML 178 +/- 188 pg/ml). In RA patients, IL-8 levels could not be related to various serological, clinical or radiological parameters. However, a correlation was observed between SF levels of IL-8 with those of lactate, LDH, beta 2-microglobulin and glucose. These observations suggest that next to the laboratory parameters IL-8 will be a parameter of the activity of the local inflammatory process. The results also demonstrate that IL-8 is not a disease-specific marker of joint inflammation.
Clin Rheumatol 1993 Dec
PMID:Interleukin-8 (IL-8) in synovial fluid of rheumatoid and nonrheumatoid joint effusions. 812 12

In an attempt to understand more directly the molecular mechanisms involved in the cellular response of endothelial cells to Interleukin-1 (IL-1), we have made several cDNA libraries from human umbilical vein endothelial cells (HUVEC) stimulated for 1 h with IL-1 in the presence of cycloheximide. The cDNA libraries were differentially screened with labelled cDNA derived from mRNA isolated from untreated or IL-1 treated HUVEC. Forty cDNA clones induced by IL-1 were isolated and partially sequenced. Thirty-eight of these corresponded to known genes, that is IL-8, ELAM-1, GRO-alpha, GRO-beta, PA-I and I-kB. The last two clones contained an identical insert belonging to a previously unknown gene. The full length cDNA of this new gene was isolated and called PTX3. It encodes for a 42 kD, 381 amino-acid long protein which shows in its 3' half a high degree of homology to all the known members of the pentaxin gene family, including C-reactive protein (CRP) and serum amyloid P component (SAP). PTX3 may represent a novel marker of inflammatory reactions, particularly those involving the vessel wall.
Eur Heart J 1993 Dec
PMID:IL-1 inducible genes in human umbilical vein endothelial cells. 813 94

Antibiotic-induced endotoxin (lipopolysaccharide; LPS) release may precipitate septic shock. In the present study the effect of teicoplanin, which has been reported to neutralize LPS in experimental models, on LPS neutralization was investigated in human whole blood samples. Levels of interleukin 8, a preinflammatory cytokine which was stimulated by Salmonella minnesota R595 LPS (12.6 micrograms/ml), were monitored over time. Interleukin 8 concentrations increased over time up to 24 h. When LPS was preincubated with teicoplanin (antibiotic: LPS ratio 20:1, w/w), interleukin 8 concentrations were found significantly (p < 0.05) reduced at 4, 8 and 24 h after LPS challenge. Interleukin 1 beta (at 4, 8 and 24 h) and tumor necrosis factor alpha (at 8 and 24 h) levels were also significantly decreased by teicoplanin. In this experiment model, a teicoplanin:LPS ratio 100-fold less than the ratio achievable in plasma of septic shock patients was able to reduce interleukin 8, which has been correlated with the severity of septic disease.
Eur J Clin Microbiol Infect Dis 1993 Dec
PMID:Inhibition of endotoxin-induced interleukin 8 release by teicoplanin in human whole blood. 818 90

In recent years, there has been a growing body of evidence suggesting that IL-8 and granulocyte-macrophage CSF (GM-CSF) play an important role in inflammatory processes. We show that after GM-CSF treatment, the exposure of human neutrophils to IL-8 results in the synthesis of leukotriene (LT)B4 and platelet-activating factor. In GM-CSF-treated cells, IL-8 induced a concentration-dependent synthesis of both lipid mediators, with a threshold at 10 to 30 nM, suggesting that IL-8 could stimulate phospholipase A2 activity, an enzyme essential for both syntheses. Accordingly, IL-8 induced a substantial release of 3H-arachidonic acid in GM-CSF-treated PMN. It was also found that IL-8 activates the neutrophil 5-lipoxygenase (5-LO), the other key enzyme in LT biosynthesis. IL-8 induced 5-LO activation in a time- and concentration-dependent manner, with a threshold at 1 nM, and prior treatment of neutrophils with GM-CSF enhanced this effect of IL-8 over the 1 to 300 nM range. Neutrophil-activating peptide-2 and the melanoma growth-stimulatory activity, two peptides that are closely related to IL-8, also had the ability to activate the 5-LO and stimulate LT synthesis, albeit less potently than IL-8. Finally, pertussis toxin and the 5-LO translocation inhibitor, MK-886, both blocked the IL-8-elicited 5-LO activation. Taken together, our results raise the possibility that the combined presence of IL-8 and of GM-CSF at inflammatory foci could result in the synthesis of platelet-activating factor and LTB4 by neutrophils, thereby contributing to the amplification of the inflammatory response.
J Immunol 1993 Dec 01
PMID:Induction by chemokines of lipid mediator synthesis in granulocyte-macrophage colony-stimulating factor-treated human neutrophils. 824 74

To define the structural features important for IL-8 binding to its two known receptors, mutants of IL-8 and melanoma growth-stimulating activity (MGSA) and chimerae consisting of segments of these two chemokines were constructed and purified from the pGEX 2T Escherichia coli expression vector. IL-8 alpha and beta receptors were expressed stably and individually in 293 kidney epithelial cells and HL60 human leukemia cells. The Kd for IL-8 itself and copy numbers for both receptors in transfected cells were comparable. Competition binding with 125I-labeled IL-8, however, showed large differences for several of the IL-8 mutants between alpha and beta receptors. The amino-terminal ELR sequence was important for IL-8 binding to the alpha receptor, but not sufficient for high affinity binding. Both rabbit IL-8 and MGSA share the ELR sequence with human IL-8, but compete poorly with it. The carboxyl terminus distal to amino acid 50 does not seem to mediate high affinity binding to the alpha receptor. A rabbit IL-8/human IL-8 chimera that differs in only eight amino acids from the human IL-8 sequence, was 150-fold lower in its affinity for the alpha receptor than human IL-8. In contrast, both the amino and carboxyl termini appear to be important for binding to the beta receptor. If the ELR sequence of IL-8 was substituted with alanines or if the carboxyl terminus distal to C50 was replaced with the MGSA sequence, a reduction occurred in binding competition. If both changes were introduced simultaneously, binding was abolished. Binding of MGSA was completely prevented by replacement of the ELR sequence with alanines. Ca2+ mobilization in HL60 cells transfected with the alpha or beta receptor was used to assess cell stimulation. The various mutant forms of IL-8 induced receptor activity with a pattern of sensitivity parallel to the competition binding affinities, indicating that both receptors are active.
J Immunol 1993 Dec 01
PMID:Multiple sites on IL-8 responsible for binding to alpha and beta IL-8 receptors. 824 75

To better understand the cellular target(s) of cyclosporin action in psoriasis, we have studied the effects of systemic short-term (7 d), low-dose (3-7.5 mg/kg) cyclosporin A administration on the expression of the cytokines interleukin (IL)-8 and IL-1 beta in psoriatic lesions. RNA blot hybridization analysis of pretreatment keratome biopsies revealed that expression of both cytokine mRNAs was highly variable from patient to patient. Significant covariation of both cytokine mRNA levels was noted (r = 0.86, p < 0.0001). However, there was no significant correlation between expression of either cytokine and clinical severity, as measured by the pretreatment Psoriasis Area and Severity Index (PASI). IL-1 beta protein levels measured by enzyme-linked immunosorbent assay (ELISA) were highly correlated with IL-1 beta mRNA levels, indicating that the differences in transcript levels accurately reflect differences in epidermal cytokine protein. Significant reductions in both cytokine transcripts and in IL-1 beta immunoreactive protein were noted in the high expression subgroup after 1 week of cyclosporin A therapy, prior to detectable clinical improvement. In contrast to its pronounced effects on epidermal cytokine expression in vivo and the allogeneic mixed lymphocyte reaction in vitro, cyclosporine A did not inhibit the induction of intercellular adhesion molecule (ICAM)-1 or IL-8 mRNAs by cultured keratinocytes in response to IL-1 beta or the combination of tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma. These data suggest that epidermal keratinocytes respond to signals produced by activated T cells by coordinate expression of multiple cytokines, and that cyclosporin A acts primarily through blockade of T cells, rather than through keratinocyte activation.
J Invest Dermatol 1993 Dec
PMID:Cyclosporin A rapidly inhibits epidermal cytokine expression in psoriasis lesions, but not in cytokine-stimulated cultured keratinocytes. 824 2


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