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)

T cell locomotion within the extracellular matrix may be mediated by cell adhesion molecules. We investigated the expression and function of beta 1- and beta 2-integrins and CD44 on human peripheral CD4+ and CD8+ lymphocytes locomoting in a 3-D type I collagen matrix. Paths of randomly selected T cells were digitized from time-lapse videorecordings and were quantitatively analyzed. After the blocking of CD49b with mAb Gi9, the locomotion of a defined locomotor subset (50% of spontaneously locomoting cells) was inhibited. Anti-CD49d mAb HP2/1 and an activating anti-CD44 mAb (J173), respectively, induced transient recruitment (< 1 h) of previously nonmotile cells (10 to 35%). In contrast to the J173-induced short-term locomotion, hyaluronan incorporated within the matrix promoted locomotion for > 2 h. No significant effects were present for anti-CD49f (GoH3) and -CD11a (25.3) mAbs. After the addition of IL-8 to the matrix, rapid induction of locomotion in 20 to 30% of the cells (control) was evident, which was virtually abolished by anti-alpha 2- and alpha 6-integrin, and -CD11a mAbs. Thus, the locomotion of nonactivated and IL-8-activated T cells may involve different sets of integrins. Using flow cytometry, the development of a CD49b+CD29highCD44lowL-selectinlow T cell phenotype independent of activation markers including CD25, CD27, CD28, VLA-4, and CD45RA- to CD45RO-transition was observed after 4 days in the matrix. The initial development of spontaneous locomotion in the collagen matrix, however, was not accompanied by alterations in CAM surface staining and, therefore, may involve functional CAM activation rather than involving an increase in surface expression.
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PMID:T lymphocyte locomotion in a three-dimensional collagen matrix. Expression and function of cell adhesion molecules. 753 96

IL-8, a potent chemotactic factor for neutrophil granulocytes and lymphocytes, is a proinflammatory cytokine secreted by a variety of cell types, including T cells. Stimulation of the CD28 cell surface molecule delivers costimulatory signals essential for lymphokine production in activated T cells via a conserved sequence element found in the promoter of several lymphokine genes. Anti-CD28-stimulated T cells produced significant amounts of IL-8; additionally, costimulation with anti-CD3 and anti-CD28 Abs resulted in a synergistic induction of IL-8 secretion. Sequence homology, single nucleotide mutations, and anti-CD28 Ab stimulation studies established that the NF-kappa B-like sequence in the promoter of the IL-8 gene functioned as a CD28 response element. Furthermore, cyclosporin A, but not rapamycin, blocked the synergistic induction of IL-8 expression achieved with anti-CD3 and anti-CD28 costimulation. The involvement of a CD28 response element in the induction of IL-8 expression in activated T cells may provide new insights into the pathogenesis and persistence of immune disorders characterized by increased levels of IL-8, such as psoriasis and rheumatoid arthritis.
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PMID:Induction of IL-8 expression in T cells uses the CD28 costimulatory pathway. 807 62

Chemokines, which include interleukin (IL)-8, are a family of pro-inflammatory molecules with potent chemoattractant activity on neutrophils, as well as other cell types. IL-8 can be recovered from many inflammatory sites. To test the hypothesis that Th2-type allergen-specific T cells, known to be the main cell type governing the allergic inflammation, are a source of IL-8 and to investigate whether IL-8 release is influenced by the nature of the in vitro mitogenic or co-mitogenic stimulation, cypress-specific T-cell clones (TCC) were generated from five allergic subjects during in vitro seasonal exposure to the allergen. Purified cypress extract was produced directly from freshly collected pollen and used for in vitro stimulation of PBMC bulk cultures. After 5 days priming and a further 7 day period of IL-2-driven cell expansion, monoclonal antibodies to CD3, CD2 and CD28 were adopted for in vitro restimulation of allergen-specific cell lines or, subsequently, secondary established TCC. The induction of apoptosis was detected by propidium iodide (PI) cytofluorimetric assay. Basal and co-stimulation-induced IL-8 production was measured by an ELISA method. Both cypress-specific T-cell lines and TCC secreted appreciable amounts of IL-8. By cross-linking T-cell lines or Th2 CD4+ TCC with CD3, CD2 or CD28 MoAbs, the authors observed a great stimulation-induced IL-8 secretion, preferentially after CD2 or combined CD2/CD28 stimulation. In addition, CD4+ clones released large amounts of IL-8 into culture supernatants after CD2 stimulation while undergoing programmed cell death (30-40% hypodiploid DNA profile of PI-stained cells). In contrast, CD3 crosslinking was unable to determine the release of IL-8 or the induction of apoptosis. Taken together, these results suggest that incomplete TcR engagement by allergen may lead to the secretion of pro-inflammatory cytokines with a contemporary induction of apoptosis in a significant number of target cells. This phenomenon may represent an additional way for local recruitment of neutrophils and basophils.
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PMID:Co-stimulation-induced release of pro-inflammatory cytokine interleukin-8 by allergen-specific T cells. 869 95

Several studies have shown that CC chemokines attract T lymphocytes, and that CD45RO+, memory phenotype cells are considered to be the main responders. The results, however, have often been contradictory and the role of lymphocyte activation and proliferation has remained unclear. Using CD45RO+ blood lymphocytes cultured under different stimulatory conditions, we have now studied chemotaxis as well as chemokine receptor expression. Expression of the RANTES/MIP-1 alpha receptor (CC-CKR1) and the MCP-1 receptor (CC-CKR2) was highly correlated with migration toward RANTES, MCP-1, and other CC chemokines, and was strictly dependent on the presence of IL-2 in the culture medium. Migration and receptor expression were rapidly downregulated when IL-2 was withdrawn, but were fully restored when IL-2 was added again. The effect of IL-2 could be partially mimicked by IL-4, IL-10, or IL-12, but not by IL-13, IFN gamma, IL-1 beta, TNF-alpha, or by exposure to anti-CD3, anti-CD28 or phytohemagglutinin. Activation of fully responsive lymphocytes through the TCR/CD3 complex and CD28 antigen actually had the opposite effect. It rapidly downregulated receptor expression and consequent migration even in the presence of IL-2. In contrast to the effects on CC chemokine receptors, stimulation of CD45RO+ T lymphocytes with IL-2 neither induced the expression of the CXC chemokine receptors, IL8-R1 and IL8-R2, nor chemotaxis to IL-8. The prominent role of IL-2 in CC chemokine responsiveness of lymphocytes suggests that IL-2-mediated expansion is a prerequisite for the recruitment of antigen-activated T cells into sites of immune and inflammatory reactions.
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PMID:Interleukin-2 regulates CC chemokine receptor expression and chemotactic responsiveness in T lymphocytes. 876 Jul 84

Ligation of CD28 provides a costimulatory signal essential for Ag-mediated T cell activation via the TCR. Blocking CD28 ligation can inhibit cytokine expression and elicits a state of T cell hyporesponsiveness. In this study, we examined the effect of inhibiting CD28 expression on in vitro and in vivo T cell responses. To address this, we have synthesized a series of G-rich phosphorothioate oligonucleotides that inhibited activation-induced transcription and cell surface expression of CD28 on human T cells. CD28 blockade was selective, as expression of other activation-induced receptors was unaffected by oligonucleotide treatment. Using strategic changes to base composition, we identified a minimal 12-mer sequence, containing two sets of four contiguous guanosines separated by 3 to 5 bases, which conferred activity in vitro. Furthermore, inhibition of CD28 expression mediated by one representative active oligonucleotide, GR1, resulted in a concomitant dose-dependent diminution of anti-CD3/PMA-induced cytokine (IL-2, IFN-gamma, IL-8) production. Inhibition of IL-2 synthesis was dependent on CD28 expression, as GR1 failed to abrogate activated IL-2 production in a CD28-deficient T cell line, HUT 78. The inhibitory activity of GR1 reduced T cell proliferative responses in MLR and induced Ag-specific T cell hyporesponsiveness to alloantigens. Finally, s.c. administration of GR1 impaired in vivo contact hypersensitivity responses in mice and was associated with substantially decreased CD28 and IFN-gamma mRNA expression in lymph node cells. Collectively, our studies show the tolerogenic potential of oligonucleotide-mediated CD28 inhibition on T cell activation, in vitro and in vivo.
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PMID:Oligonucleotide-mediated inhibition of CD28 expression induces human T cell hyporesponsiveness and manifests impaired contact hypersensitivity in mice. 897 91

The objective of the present study was to investigate the effects of isolated limb perfusion (ILP) with tumour necrosis factor alpha (TNF-alpha) and melphalan in patients with cancer on, first, plasma levels of cytokines, second, systemic monocyte and T-lymphocyte distribution and, third, the ability of mononuclear cells to produce cytokines upon stimulation in vitro. Six patients undergoing an ILP were entered into the study (group 1). In addition, patients undergoing a major surgical operation (group 2) minor operation (group 3) as well as healthy volunteers (group 4) were included as control groups. Sensitive enzyme-linked immunosorbent assays (ELISAs) were used to measure TNF-alpha and interleukin-6 (IL-6) plasma levels at various time points during and after operation. Furthermore, the percentage of monocytes and T lymphocytes was determined in all studied groups using a FACScan. In addition, cytokine production upon stimulation with lipopolysaccharide (LPS) and a combination of anti-CD3/anti-CD28 monoclonal antibodies in whole-blood cultures was investigated. Increased plasma levels of TNF-alpha and IL-6 in patients undergoing ILP was observed, but only IL-6 appeared to be increased in patients treated with a major operation. No significant fluctuations were found in the other groups studied. Concerning the number of monocytes, a significant decrease was observed only in patients treated with ILP. Furthermore, a decreased production of TNF-alpha, IL-6 and IL-8 upon various types of stimulation in vitro was found in those patients, but also after a major operation. In conclusion, the results of the present study show increased plasma levels of cytokines in patients treated with ILP and major operation. Furthermore, a decrease in numbers of monocytes in the circulation and the ability of mononuclear cells to produce cytokines in vitro may be induced by administration of TNF-alpha in ILP. Although similar results were found in patients treated with major operation, the underlying mechanisms of this phenomenon remain to be elucidated.
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PMID:Effects of isolated limb perfusion with tumour necrosis factor-alpha on the function of monocytes and T lymphocytes in patients with cancer. 901 83

The interleukin-12 receptor (IL-12R)beta1 chain is an essential component of the functional IL-12R on both human T and natural killer cells. In this report it is shown that activation of human peripheral blood mononuclear cells (PBMC) with anti-CD3 monoclonal antibody (mAb) or phytohemagglutinin resulted in the up-regulation of IL-12Rbeta1 expression and IL-12 binding. Kinetic studies revealed that maximum expression of IL-12Rbeta1 and IL-12 binding occurred on days 3-4. Anti-CD3-induced expression of IL-12Rbeta1 chain and IL-12 binding by PBMC was augmented by anti-CD28 mAb, indicating that the potentiating effect of anti-CD28 on T cell responses to IL-12 could be mediated, at least in part, by the enhancement of IL-12R expression. Among 16 cytokines tested, IL-2, IL-7 and IL-15 markedly induced IL-12Rbeta1 expression and IL-12 binding on resting PBMC, whereas IL-1alpha and tumor necrosis factor-alpha had a minimal enhancing effect. In contrast, IL-3, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, interferon (IFN)-alpha, IFN-gamma, granulocyte/macrophage colony-stimulating factor and transforming growth factor (TGF)-beta2 had no detectable enhancing effect. Anti-CD3-induced expression of IL-12Rbeta1 and of low-affinity IL-12 binding sites was partially inhibited by TGF-beta2, IL-10 and IL-4; however, TGF-beta2 and IL-10 completely abolished anti-CD3-induced expression of high-affinity IL-12 binding sites. Consistent with the reduction of high affinity IL-12 binding sites, PBMC activated with anti-CD3 mAb in the presence of TGF-beta2 or IL-10 failed to produce IFN-gamma or to proliferate in response to IL-12. These results suggest that Th2 cell-derived cytokines can inhibit IL-12-induced biological functions by inhibiting IL-12R expression and that expression of a second subunit of the IL-12R (IL-12Rbeta2), required for the formation of high-affinity IL-12 binding sites, may be more highly regulated by TGF-beta2 and IL-10 than is expression of IL-12Rbeta1.
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PMID:Regulation of interleukin-12 receptor beta1 chain expression and interleukin-12 binding by human peripheral blood mononuclear cells. 902 11

Image analysis was used to study the cytokine-inhibitory effect of the nitric oxide inhibitor tetravalent guanylhydrazone (CNI-1493) in individual immunocytochemically stained human peripheral blood mononuclear cells (PBMC). CNI-1493 inhibited lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-alpha, interleukin (IL)-1alpha, IL-1beta, IL-6, and IL-8 production whether or not LPS stimulation was enhanced by interferon (IFN)-gamma priming. Addition of TNF-alpha to CNI-1493-exposed LPS-stimulated cells partially restored the incidence of IL-1alpha-, IL-1beta-, and IL-8-producing cells. TNF-alpha production induced by costimulation by ligation of CD3 and CD28 was inhibited by CNI-1493 in monocytes but not in T lymphocytes. The prevalence of IL-2-, IFN-gamma-, and TNF-beta-producing T cells was not reduced by CNI-1493. Phorbol ester and ionomycin activation also resulted in a CNI-1493 -induced inhibition of TNF-alpha in monocytes but resistant production of TNF-alpha, IL-2, and IFN-gamma by T cells. Thus, CNI-1493 preferentially inhibited synthesis of proinflammatory cytokines in monocytes.
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PMID:Targeted suppression of cytokine production in monocytes but not in T lymphocytes by a tetravalent guanylhydrazone (CNI-1493). 935 32

Elevated levels of circulating IL-8, a potent chemotactic factor for granulocytes and T lymphocytes, are found in HIV-infected individuals. The HIV-1 transactivator protein Tat increased IL-8 secretion in T cell lines following CD3- and CD28-mediated costimulation. Full-length Tat (Tat101) enhanced IL-8 transcription through up-regulated transcription factor binding to the CD28-responsive element (CD28RE) in the IL-8 promoter. Expression of the Tat splice variant Tat72 (72 amino acids) also enhanced IL-8 production following T cell stimulation via a different, most likely post-transcriptional, mechanism. The CD28RE in the IL-8 promoter was characterized as a low-affinity NF-kappaB binding site recognized by the transcription factors p50 (NF-kappaB1), p65 (RelA) and c-rel. Transcription factor binding to "classical" NF-kappaB sites in the HIV-1, the human IL-2, and lymphotoxin promoters, recognized by p50 and p65 following CD3+28-mediated costimulation, was unaffected by Tat101 as was binding to the AP-1 motif in the IL-8 promoter. These experiments identify the CD28RE in the IL-8 promoter as a c-rel recognition site and a Tat101-responsive element. The effect of Tat101 on CD28REs in the IL-8 promoter and the subsequent up-regulation of IL-8 secretion is likely to contribute to the immune dysregulation observed during HIV-1 infection.
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PMID:Superinduction of IL-8 in T cells by HIV-1 Tat protein is mediated through NF-kappaB factors. 951 Jan 90

Ultraviolet (UV) irradiation of the skin induces complex local and systemic immunomodulatory reactions. The biological effects of UV irradiation on human skin derived afferent lymph however are unknown. The aim of this study was to examine the effects of a single combined UV-A and UV-B irradiation with 1 minimal erythema dose (MED) on human skin derived lymph in vivo. After cannulation of a superficial lymph vessel on the lower leg, lymph flow and cell output per hour were determined before and for 6 days after UV irradiation of the lymph draining skin area in 5 volunteers. Furthermore, expression of CD1a, CD4, CD8, CD28, CD54, CD80, CD86 and HLA-DR on migrating lymph cells and cytokine levels (IL-1alpha, IL-1beta, IL-2, IL-6, IL-8, IL-10, IL-13, TNF-alpha and IFN-gamma) in the afferent lymph were analyzed by cytofluorometry and ELISA. After UV irradiation a small initial enhancement in the daily lymph flow per hour was noticed in correlation with the slight erythematous skin reaction. Following resolution of the skin reaction, a delayed increase in cell output in correlation with an additional peak in the lymph flow was found between the 4th and 6th day after UV irradiation. However, no changes in the expression of CD1a, CD4, CD8, CD28, CD54, CD80, CD86 and HLA-DR on migrating lymph cells were detectable. Interestingly, in parallel to the increased lymph flow and cell output, only elevated IL-8 protein levels were reproducibly detected in the afferent lymph after UV irradiation. Furthermore, using immunohistochemistry positive staining for IL-8 was found on migrating mononuclear lymph cells. In conclusion, our data demonstrate that a single UV irradiation of the skin with 1 minimal erythema dose leads to a delayed enhancement of lymph flow, number of migrating lymph cells and cytokine levels of IL-8. Moreover, we provide evidence that migrating lymph cells, besides resident epidermal and dermal cells, may contribute to the detected levels of IL-8 in the afferent lymph.
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PMID:Effects of UV irradiation with one minimal erythema dose on human afferent skin lymph in vivo. 985 39


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