Molecular cloning of a human monocyte-derived neutrophil chemotactic factor (MDNCF) and the induction of MDNCF mRNA by interleukin 1 and tumor necrosis factor

Expression of interleukin-8, heme oxygenase-1 and vascular endothelial growth factor in DLD-1 colon carcinoma cells exposed to pyrrolidine dithiocarbamate

Interleukin (IL)-8, heme oxygenase-1 (HO-1), and vascular endothelial growth factor (VEGF) appear to be critically involved in immune responses associated with inflammation, infection and tumor growth. Regulation of these mediators was studied in the human colon carcinoma cell line DLD-1. Here we report that pyrrolidine dithiocarbamate (PDTC) not only augmented tumor necrosis factor-alpha-induced release of IL-8, but also mediated IL-8 expression as a single stimulus. Mutational analysis of the IL-8 promotor and electrophoretic mobility shift analysis revealed that activation of the transcription factor activator protein-1 (AP-1) and a constitutive nuclear factor-kappaB (NF-kappaB) binding activity in DLD-1 cells were mandatory for PDTC-induced IL-8 expression. Besides IL-8, PDTC also upregulated the expression of HO-1 and VEGF in these cells. Induction of IL-8 by PDTC was not restricted to DLD-1 cells, but was observed in Caco-2 colon carcinoma cells and in peripheral blood mononuclear cells. PDTC is currently advocated for use as a chemotherapeutic drug in the treatment of certain malignancies, among them colorectal cancer. Induction of IL-8, HO-1 and VEGF may affect therapeutic applications of this agent.

Pro-inflammatory and anti-inflammatory cytokine increases after spinal instrumentation surgery

We investigated the effects of instrumentation on postoperative inflammatory reaction and identified standard changes in serum cytokine concentrations after spinal surgery. Pro-inflammatory cytokines [interleukin (IL)-6 and IL-8] and anti-inflammatory cytokines [IL-10, IL-1 receptor antagonist (ra), and soluble tumor necrosis factor receptors (sTNF-R) I and II] were assayed in serum from seven patients with lumbar spinal posterior decompression, six with spinal decompression and posterolateral fusion without instrumentation and seven with spinal decompression and posterolateral fusion with instrumentation. All cytokines after spinal instrumentation increased significantly more than in other groups on postoperative days 0 and 1. Seven days after SI, IL-6, -8, and -10 had normalized, but IL-1ra and sTNF-RI and sTNF-RII remained elevated. Both pro-inflammatory and anti-inflammatory cytokines were enhanced by implants in the acute phase, whereas only anti-inflammatory cytokines were enhanced by instruments in the subacute phase.

Interleukin-8 and tumor necrosis factor alpha production in human epidermal keratinocytes induced by Trichophyton mentagrophytes

Production of interleukin-8 (IL-8) and tumor necrosis factor alpha (TNF-alpha) was confirmed by enzyme-linked immunosorbent assay in a medium where human epidermal keratinocytes were cocultured with Trichophyton mentagrophytes for 1 to 12 h. IL-8 and TNF-alpha mRNAs were also detected in the keratinocytes cocultured with T. mentagrophytes.

Chemokines and inflammation in the nasal passages of infants with respiratory syncytial virus bronchiolitis

This study measured chemokines in nasal lavage fluids (NLF) from infants with respiratory syncytial virus (RSV) bronchiolitis, defined by lung hyperinflation and wheezing. Comparison was made to RSV-positive infants without bronchiolitis and RSV-negative infants with acute respiratory illnesses. RSV-positive illnesses were associated with increased epithelial shedding, increased RANTES/protein ratios, and increased IL-8/protein ratios in NLF compared to RSV-negative illnesses. Among RSV-positive infants, bronchiolitics had greater total cell counts and percentage epithelial cells in NLF than nonbronchiolitics. Bronchiolitics also had roughly twice the NLF RANTES/IL-8 ratio than nonbronchiolitics (P =.043). Semiquantitative reverse transcriptase-polymerase chain reaction of nasal epithelium suggested similar RANTES/IL-8 ratio increases among bronchiolitics. A more mildly affected, RSV-positive outpatient population showed none of these differences. We conclude that RSV bronchiolitis is associated with a shift toward relatively more RANTES in nasal secretions of infants sick enough to require hospitalization, and mucosal epithelium may contribute to this process. Similar processes in the lower airways may enhance inflammation due to RANTES-responsive cell types and affect clinical manifestations.

Identification and analysis of an interleukin 8-like molecule in rainbow trout Oncorhynchus mykiss

An interleukin 8 (IL-8) homologue has been identified in the rainbow trout Oncorhynchus mykiss. The transcript contains an open reading frame of 294 nucleotides that translates into a 97 amino acid putative peptide, with 5' and 3' untranslated regions (UTR) of 171 and 453 nucleotides, respectively. As with previously sequenced lamprey and flounder genes, the trout amino acid sequence lacks the typical ELR motif upstream of the first pair of cysteines, where DLR is present. The trout IL-8 gene contains four exons divided by three short introns of 341, 247 and 292bp, and occupies 1824bp of genomic DNA. RT-PCR reveals a low level constitutive expression of the IL-8 homologue in many tissues, including spleen, heart, liver, head kidney and gill. Expression was not detectable in the brain. Whilst no apparent affect of lipopolysaccharide (LPS) on IL-8 expression was observed in vivo, stimulation of a trout macrophage cell line (RTS-11) with either LPS or poly I:C did result in clear up-regulation of IL-8 expression, detectable by RT-PCR and Northern blot analysis.

The role of chemokines in melanoma tumor growth and metastasis

Chemokines represent a large family of polypeptide signaling molecules that are notable for their role in chemotaxis, leukocyte homing, directional migration, and G protein coupled receptor activation. Chemo kines have recently been implicated in tumor progression and metastasis. The demonstration of chemokine expression and receptor activation in melanoma tumor cells themselves, and the tumor infiltrating leukocytes, may have important implications in terms of tumor progression and tumor cell homing to metastatic sites. In addition to their chemotactic and cell homing properties, chemokines and their receptors also play a part in other biologic functions relevant to oncogenesis, including cell proliferation, protease induction, tumor growth, and angiogenesis. Melanomas, and the cells derived from them, have been found to express a number of chemokines, including CXCL8 (interleukin-8), CXCL1-3 (MGSA-GROalpha-gamma), CCL5 (RANTES), and CCL2 (monocyte chemotactic protein-1), which have been implicated in tumor growth and progression. Furthermore, recent studies have demonstrated organ-specific patterns of melanoma metastasis that correlate with their expression of specific chemokine receptors, including CXCR4, CCR7, and CCR10. This review will focus on the current biology of chemokines and chemokine receptors in the context of understanding their potential roles in melanoma progression and metastasis, and is not meant to be a comprehensive review of chemokine biology. Continued understanding and progress in the determination of the role of chemokines and their receptors in tumorigenesis and metastasis, including melanoma, may lead to novel approaches in the treatment and management of this disease.

The presence of cytokine (IL-8, IL-1alpha, IL-1beta)-producing cells in inflamed gingival tissue from a patient manifesting Papillon-Lefevre syndrome(PLS)

The point of this study was to examine the presence or absence of cytokine-positive cells by means of immunohistochemical methods in the samples of inflamed gingival tissues obtained from an 11-year-old girl with Papillon-Lefevre syndrome (PLS). Interleukin-8 (IL-8)-positive cells were found to be present. In addition, IL-1alpha-and IL-1beta-positive cells were detected. No dysfunction in the phagocytosis and the bacterial killing of peripheral blood polymorphonuclear neutrophils (PMNs) was observed in this patient. Our findings suggest that these cytokines may be members responsible for modulating the process of rapidly progressive periodontitis for patient with PLS.

Increased levels of interleukin-8 in BAL fluid from smokers susceptible to pulmonary emphysema

BACKGROUND

It has previously been shown that smokers with computed tomographic (CT) evidence of subclinical emphysema have signs of neutrophil activation, despite having no appreciable increase in the number of neutrophils in their bronchoalveolar lavage (BAL) fluid.

METHODS

The levels of the following chemoattractants in BAL fluid from 61 community based older volunteers classified into four groups according to current smoking status and the presence or absence of emphysema were determined: interleukin 8 (IL-8), epithelial neutrophil activating protein 78 (ENA-78) and leukotriene B(4) (LTB(4)) which are primarily chemotactic for neutrophils; monocyte chemoattractant protein 1 (MCP-1) and macrophage inflammatory protein-1alpha (MIP-1alpha) which are predominantly chemotactic for mononuclear leucocytes.

RESULTS

Of the five chemoattractants studied, only the level of IL-8 in BAL fluid clearly distinguished between subjects with and without emphysema among current smokers (median values 34.7 and 12.2 pg/ml, respectively, p<0.01). In addition, the levels of IL-8 and neutrophil elastase-alpha(1) protease inhibitor complex in BAL fluid were significantly correlated (r=0.65, p<0.01). There was no difference in either the release of IL-8 from cultured alveolar macrophages at 24 hours or the expression of IL-8 messenger RNA of alveolar macrophages in the two groups of current smokers with and without emphysema.

CONCLUSION

An accelerated response of IL-8 to chronic smoking is a factor that characterises those smokers who are susceptible to pulmonary emphysema, although the cellular source of IL-8 remains to be determined.

Feline interleukin-8 expression in peripheral blood mononuclear cells induced by egg white derivatives

Feline peripheral blood mononuclear cells (PBMC)-derived chemotactic factor induced by egg white derivatives (EWD) treatment was analyzed at the protein and messenger ribonucleic acid (mRNA) level. EWD itself was not active chemotactic for feline peripheral blood polymorphonuclear cells (PMN). But chemotaxis of PMN was enhanced by either culture supernatant from PBMC treated with EWD or human recombinant (hr) interleukin (IL)-8. Both hr IL-8 and the culture supernatant from PBMC treated with EWD yielded a distinct band, molecular weight of 6-8kDa, in sodium-dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) with 15% loading gel. Therefore, to identify this chemotactic factor, culture supernatant from PBMC treated with EWD was partially purified by anion exchange chromatography on diethylaminoethyl (DEAE)-Sepharose CL-6B and concentrated by ultrafiltration. Only the fraction, which was eluted with 0.3M NaCl, showed a high concentration of total protein and also enhanced the chemotactic activity of PMN. This activity was thereafter designated as eluate. The chemotactic activity of eluate was inhibited by anti-hr IL-8 polyclonal antibody (pAb). A single protein band with 6-8kDa was shown in both the eluate and hr IL-8 when analyzed by SDS-PAGE and Western blotting using anti-hr IL-8 pAb, suggesting that the chemotactic factor for feline PMN is IL-8, 6-8kDa, produced by PBMC treated with EWD. The physicochemical characteristics of eluate were stable in heated (60-100 degrees C), acid (pH 3.0), and alkaline (pH 9.0) conditions. The eluate under these conditions also showed a distinct band in molecular weight of 6-8kDa in SDS-PAGE and Western blotting and was very active in chemotactic activity of PMN.IL-8 mRNA gene expression on feline PBMC was analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) assay using a series of oligonucleotides, each 22 mer, derived from feline IL-8. Feline IL-8 mRNA showed low level in 3-h incubation without EWD, but it was increased in a dose-dependent manner by addition of EWD. Following EWD (10 microg/ml) treatment, IL-8 mRNA expression was rapidly increased up to 6h and decreased by 12h although it was not expressed in freshly prepared PBMC. This study strongly suggested that immunoenhancing effect of EWD on chemotactic response of PMN is mediated by feline IL-8, 6-8kDa, produced by PBMC stimulated with EWD. In addition, the expression of feline IL-8 mRNA on PBMC is increased when stimulated with EWD.

Regulation of constitutive and induced NF-kappaB activation in malignant melanoma cells by capsaicin modulates interleukin-8 production and cell proliferation

In the present study, we demonstrate that upregulation of interleukin-1beta(IL-1beta)-mediated and tumor necrosis factor-alpha (TNF-alpha)-mediated IL-8 expression in human malignant melanoma cells is modulated by the activation of nuclear factor-kappaB (NF-kappaB). Addition of capsaicin (8-methyl-N-vanillyl-6-nonenamide), a known inhibitor of NF-kappaB, resulted in the inhibition of constitutive as well as IL-1beta-induced and TNF-alpha-induced IL-8 expression in melanoma cells. The inhibition of IL-8 expression was dependent on the concentration of capsaicin and duration of treatment. Further, electrophoretic mobility shift assay (EMSA) of nuclear extracts from melanoma cells showed a constitutive activation of NF-kappaB and activated protein 1 (AP-1), which was upregulated following treatment with IL-1beta. Treatment of melanoma cells with capsaicin inhibited activation of constitutive and IL-1beta-induced NF-kappaB, but not AP-1, leading to inhibition of IL-8 expression. Further, downregulation of IL-8 expression in capsaicin-treated melanoma cells resulted in inhibition of in vitro cell proliferation. These results demonstrate that constitutive and induced NF-kappaB activation regulates IL-8 expression in melanoma cells. Downregulation of constitutive and induced NF-kappaB activation in malignant melanoma cells leads to inhibition of IL-8 production and in vitro cell proliferation.

Differential production of RANTES and MCP-1 in synovial fluid from the inflamed human knee

Synovial production of chemokines may play an important role in the recruitment of phagocytic leukocytes during inflammation. MCP-1, as well as RANTES mediate many different inflammatory diseases and are important in the recruitment of diverse leukocytes. We set out to study the different production of MCP-1 and RANTES in three different inflammatory conditions of the knee: arthrosynovitis, mechanical trauma, and hyperuricemia. In this study we evaluated if in each pathological condition mentioned above, there was a prevalence in production of one chemokine over the other. ELISA method was used to determine base production of the chemokines in the synovial fluid, serum and in supernatants from activated inflammatory cells. RANTES and MCP-1 messenger RNA (mRNA) was measured by semi-quantitative RT-PCR. Protein expression was detected by Western blot analysis. The synovial fluid cells from the knee of patients affected with arthrosynovitis, trauma, and hyperuricemia, expressed RANTES and MCP-1 and RANTES was produced in higher quantities than MCP-1 in all three pathological conditions. In patients treated with non-steroidal antiinflammatory drugs (NSAD) and dexamethasone, the levels of the two chemokines was reduced in serum and in synovial fluid. In addition, the synovial fluid cells from these patients released less RANTES and MCP-1 when compared to untreated patients. We conclude that in arthrosynovitis, trauma and hyperuricemia, RANTES and MCP-1 are both expressed and RANTES is produced in higher quantities. The fact that these chemokines are found in the three inflammatory diseases suggests that RANTES and MCP-1 are not specific to these inflammatory diseases, however they play a key role in inflammation by recruiting mononuclear leukocytes in the inflamed knee joint.

Immunoglobulins and cytokines level in follicular fluid in relation to etiology of infertility and their relevance to IVF outcome

OBJECTIVE

The aims of the present study were to (i) determine the presence and concentration of albumin fractions (alpha1, alpha2, beta, gamma), immunoglobulins (IgA, IgG, IgM) and cytokines [interleukin (IL)-6, IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF)] in periovulatory ovarian follicular fluid (FF) of in vitro fertilization (IVF) patients, (ii) examine the relationship between these parameters and the etiology of infertility as well as the IVF outcome and (iii) find out if these parameters in FF could be used as a predictive factor of IVF outcome.

DESIGN

The levels of albumin fractions, immunoglobulin and cytokines were measured from women who underwent IVF therapy for various indications and the results were compared between the patient groups and IVF outcome.

MATERIALS AND METHODS

Follicular fluid was obtained from 160 IVF patients. A total of 79 patients underwent controlled ovarian hyperstimulations (COH) either with follicle-stimulating hormone (FSH) or HMG. Whereas, the HMG was used for the second set of patients (n=81) - after down regulation with gondotropin-releasing hormone agonists (Gn-RHa) - the protein fractions were determined using electrophoresis separation. Immunoglobulins were measured using a commercial kits and the concentration of cytokines was determined by the highly sensitive enzyme-linked immunosorbent assay (ELISA) methods.

RESULTS

The stimulation regimens used have no effect on albumin (alpha1, alpha2, beta, gamma) and immunoglobulin (IgA, IgG, IgM) concentrations, as no significant difference was observed between the two groups. Besides, no specific relationship was found between the concentration of these investigated parameter in FF and etiology of infertility or fertilization, cleavage and pregnancy rate. Besides, there were no significant differences between the groups for any cytokine investigated. Moreover, there were no correlations between the concentration of IL-6, IL-8 and GM-CSF in FF and steroid hormone concentration in the blood at the day of oocytes retrieval or IVF outcome.

IN CONCLUSION

Total protein, albumin fraction, immunoglobulins and cytokines level in FF of patients undergoing COH for IVF therapy for various etiology of infertility could not be a useful parameter for predicting IVF outcome.

Upregulation of interleukin-8 expression by prostaglandin D2 metabolite 15-deoxy-delta12, 14 prostaglandin J2 (15d-PGJ2) in human THP-1 macrophages

Interleukin-8 (IL-8) is one of cytokines detected at sites of inflammation and in macrophage-foam cells of atherosclerotic lesions. The expression of IL-8 gene can be induced in cholesterol loaded THP-1 macrophages by oxidized low density lipoprotein. We report for the first time that the expression of human IL-8 gene in THP-1 macrophages is upregulated in a time- and concentration-dependent manner by prostaglandin D2 metabolite 15-deoxy-delta12, 14 prostaglandin J2 (15d-PGJ2), which is a natural ligand for activation of peroxisome proliferator-activated receptor-gamma transcription factor. Studies to identify the signal transduction pathways involved showed that IL-8 upregulation-mediated by 15d-PGJ2 was markedly inhibited when the THP-1 macrophages were incubated with a highly selective and cell-permeable inhibitor of the mitogen-activated protein kinase (MAPK) signaling pathway, 2'-amino-3'-methoxyflavone (PD98059). This inhibition was concentration-dependent, suggesting that 15d-PGJ2 regulates the expression of IL-8 gene in THP-1 macrophages through a MAPK signaling pathway. In contrast, THP-1 macrophages when treated with pyrrolidine dithiocarbamate, an anti-oxidant and the selective inhibitor for nuclear factor kappaB, showed an enhanced 15d-PGJ2-mediated upregulation of IL-8 gene expression. The data presented in this report may contribute to unravel some of the mechanisms behind the inflammatory component of atherosclerosis.

The intratumoral expression of vascular endothelial growth factor and interleukin-8 associated with angiogenesis in nonsmall cell lung carcinoma patients

BACKGROUND

Angiogenesis has important effects on tumor growth and metastasis. It is regulated by a variety of angiogenic and angiostatic factors.

METHODS

To evaluate the effects of tumor cell-derived angiogenic factors, we performed an immunohistochemic study to evaluate the intratumoral expression of vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) in relation to intratumoral microvessel density (IMD) in tumors from 104 nonsmall cell lung carcinoma (NSCLC)patients.

RESULTS

Fifty-four carcinomas were VEGF-positive, 47 carcinomas were IL-8-positive, and 53 carcinomas were hypervascular tumors. There was no significant correlation between the percentages of positive VEGF-staining and positive IL-8-staining in NSCLCs (rho = 0.174, P = 0.080). The IMD of VEGF-positive carcinomas was significantly greater than that of VEGF-negative carcinomas (P = 0.023). In addition, the IMD of IL-8-positive carcinomas was significantly greater than that of IL-8-negative carcinomas (P =0.013). The overall survival rate of patients with hypervascular tumors was significantly lower than that of patients with hypovascular tumors (41.0% versus 67.0%, P = 0.004). Cox proportional-hazards regression model also demonstrated that angiogenesis was one of the significant factors in predicting the survival of NSCLC patients (relative risk = 1.944, P = 0.041).

CONCLUSIONS

Intratumoral expression of VEGF and IL-8 was associated with angiogenesis in NSCLCs. Tumor angiogenesis significantly affected the prognosis of NSCLC patients.

Chemokines in immunity

Chemokines are a superfamily of small, heparin-binding cytokines that induce directed migration of various types of leukocytes through interactions with a group of seven-transmembrane G protein-coupled receptors. At present, over 40 members have been identified in humans. Until a few years ago, chemokines were mainly known as potent attractants for leukocytes such as neutrophils and monocytes, and were thus mostly regarded as the mediators of acute and chronic inflammatory responses. They had highly complex ligand-receptor relationships and their genes were regularly mapped on chromosomes 4 and 17 in humans. Recently, novel chemokines have been identified in rapid succession, mostly through application of bioinformatics on expressed sequence tag databases. A number of surprises have followed the identification of novel chemokines. They are constitutively expressed in lymphoid and other tissues with individually characteristic patterns. Most of them turned out to be highly specific for lymphocytes and dendritic cells. They have much simpler ligand-receptor relationships, and their genes are mapped to chromosomal loci different from the traditional chemokine gene clusters. Thus, the emerging chemokines are functionally and genetically quite different from the classical "inflammatory chemokines" and may be classified as "immune (system) chemokines" because of their profound importance in the genesis, homeostasis and function of the immune system. The emergence of immune chemokines has brought about a great deal of impact on the current immunological research, leading us to a better understanding on the fine traffic regulation of lymphocytes and dendritic cells. The immune chemokines and their receptors are also likely to be important future targets for therapeutic intervention of our immune responses.

Molecular machinations: chemokine signals in host-pathogen interactions

Chemokines and their G-protein-coupled receptors represent an ancient and complex system of cellular communication participating in growth, development, homeostasis and immunity. Chemokine production has been detected in virtually every microbial infection examined; however, the precise role of chemokines is still far from clear. In most cases they appear to promote host resistance by mobilizing leukocytes and activating immune functions that kill, expel, or sequester pathogens. In other cases, the chemokine system has been pirated by pathogens, especially protozoa and viruses, which have exploited host chemokine receptors as modes of cellular invasion or developed chemokine mimics and binding proteins that act as antagonists or inappropriate agonists. Understanding microbial mechanisms of chemokine evasion will potentially lead to novel antimicrobial and anti-inflammatory therapeutic agents.

Physiomer reduces the chemokine interleukin-8 production by activated human respiratory epithelial cells

The authors have recently shown that the transcription factor nuclear factor-kappaB (NF-kappaB) is a central mediator in the NaCl-mediated interleukin (IL)-8 production by human airway epithelial cells. In this study, it was investigated whether Physiomer, an isotonic sea water-derived solution commercialized for cleaning the nasal mucosa, impaired the chemokine IL-8 expression and secretion by human respiratory epithelial cells compared with that obtained with an isotonic 9% NaCl solution. Primary human bronchial gland (HBG) epithelial cells were incubated either in Physiomer or in a NaCl 9% solution and activated either with 20 ng x mL(-1) tumour necrosis factor-alpha, or IL-1beta, respectively. Physiomer significantly reduced the IL-8 protein release in basal and activated HBG cells in comparison with that obtained with the 9% NaCl solution. In contrast to the effects of Physiomer observed on resting HBG cells, Physiomer did not significantly reduce the level of phosphorylation of the NF-kappaB inhibitor protein IkappaBalpha or the steady-state IL-8 messenger ribonucleic acid levels in activated HBG cells, suggesting that Physiomer would have a post-transcriptional effect on IL-8 expression in activated HBG cells. The authors conclude that Physiomer is potentially useful in the reduction of airway mucosal inflammation.

Bacterial lipopolysaccharide induces transforming growth factor beta and hepatocyte growth factor through toll-like receptor 2 in cultured human colon cancer cells

This study examined, in human cancer lines, the pattern of cytokine production stimulated by lipopolysaccharide (LPS), a major component of outer surface of gram-negative bacteria, and characterized the expression pattern of CD14, cell surface LPS receptor antigen, and toll-like receptors (TLRs), which appear to be key regulators of the innate immune response system. Two colon cancer cell lines (DLD and LoVo), a hepatocellular carcinoma cell line and a myelomonocytic cell line were incubated with LPS for 0-72 h, and transforming growth factor (TGF) beta1 and beta2, hepatocyte growth factor (HGF) and interleukins 6, 8 and 15 were assayed. The only changes induced by incubation with LPS were significant increases in TGFbeta1 production at 12 h, and in HGF production at 72 h, in LPS-stimulated DLD cells, and significant increases in TGFbeta2 production after 12 h and in HGF after 72 h in LoVo cells. Using reverse transcriptase-polymerase chain reaction analysis, expression of CD14 and TLR-2 mRNA was detected in DLD and LoVo cells, and expression of TLR-4 mRNA was detected in PLC/PRF/5 and KG-1 cells. These results suggest that LPS induces TGFbeta and HGF production mediated by CD14/TLR-2 in cultured human colon cancer cell lines.

Ligation of the Fas antigen stimulates chemokine secretion in pancreatic cancer cell line PANC-1

BACKGROUND AND AIM

The role of chemokines in the process of immune cell infiltration into pancreatic cancer tissue has been reported. In this study, we investigated the induction of chemokines (interleukin (IL)-8 and monocyte chemoattractant protein (MCP)-1) by Fas antigen (Ag)-stimulation in a human pancreatic cancer cell line, PANC-1.

METHODS

The chemokine secretion was evaluated by using an ELISA and a northern blot, and the activation of nuclear factor-kappa B (NF-kappa B) was assessed by using an electrophoretic gel mobility shift assay (EMSA).

RESULTS

The Fas antigen (Ag) stimulation clearly induced an increase in IL-8 and MCP-1 secretion in PANC-1 cells. This effect was also observed at the mRNA level. The induction of chemokine secretion by Fas Ag stimulation required de novo gene expression and protein synthesis. The pretreatment with interferon (IFN)-gamma markedly enhanced the effects of Fas Ag stimulation; IFN-gamma pretreatment and Fas Ag stimulation synergistically induced not only apoptosis but also IL-8 and MCP-1 secretion. Flow cytometric analysis demonstrated that IFN-gamma significantly enhanced Fas Ag expression. In addition, Fas Ag stimulation actually evoked NF-kappa B activation in this cell line.

CONCLUSION

Our results indicate that Fas Ag stimulation can induce chemokine secretion in PANC-1 cells, suggesting the contribution of Fas stimulation to the accumulation of immune cells in pancreatic cancer tissue.

Cloning and sequence analysis of the interleukin-8 gene from flounder (Paralichthys olivaceous)

A cDNA library of mRNA from flounder leukocytes stimulated with bacterial lipopolysaccharide (LPS) and hemagglutinin was constructed to clone cytokine genes of this fish. Initial screening of this library with human cytokine gene probes was not productive and clones with inserts of over 400 nucleotides (nt) were randomly sequenced, and a homologue of the vertebrate interleukin-8 (IL-8) gene was isolated. The flounder IL-8 cDNA encompassed 884 nt, including a coding region of 330 nt. Four cysteines characteristic of CXC chemokines were identified at conserved locations in the putative protein. The deduced amino acid sequence showed 36 and 35% sequence identity with counterpart genes in monkey and human, respectively, and 52% sequence similarity with these genes. However, the putative flounder IL-8 amino acid sequence showed 25% identity and 52% similarity to that of lamprey, the only other piscine IL-8 gene that has been cloned. Flounder IL-8 transcripts were detected in the head-kidney and spleen of LPS-injected flounder and leukocytes stimulated with LPS. It was not detected in the muscle or liver of LPS-injected flounder, tissues taken from non-stimulated flounder and non-stimulated leukocytes.

Mitogenic action of tumour necrosis factor-alpha and interleukin-8 on explants of human duodenal mucosa

Our aim is to examine whether tumour necrosis factor-alpha (TNF-alpha) and interleukin affect the mitotic activity in explants of human duodenal mucosa and to estimate the release of cytokines from explants incubated with TNF-alpha. Biopsy specimens of normal duodenal mucosa were taken from 19 subjects that underwent upper endoscopy for investigation of dyspeptic symptoms or chronic gastrointestinal bleeding. The specimens were processed following guidelines for organ culture technique. Paired biopsy specimens from 12 subjects were cultured for 23 h to achieve steady state and thereafter the explants were incubated 25 h with 10(-13)-10(-9) M of TNF-alpha or IL-8. Mitoses were arrested in the metaphase by adding vincristine sulphate for the last three hours. The explants were then fixed and processed for microdissection. Fifteen crypts were microdissected and the total number of metaphases was determined using the whole crypt as reference volume. The number of metaphases per crypt was also estimated in explants incubated with 10(-10) M TNF-alpha in the presence of anti-IL-8 antibodies. Additional duodenal explants from seven subjects were incubated with 10(-10) M TNF-alpha for 25 h. Thereafter the release of IL-1-beta, IL-6, IL-8 and interferon gamma (IFN-gamma) into the culture medium was measured by enzyme immunoassay and expressed as pg/mg protein. TNF-alpha and IL-8 significantly increased the number of metaphases/crypts (P<0.0001). The addition of anti-IL-8 slightly reduced the number of metaphases/crypt compared to the values observed in the explants incubated with 10(-10) M TNF-alpha alone (P<0.0001). The number of metaphases/crypt in the explants incubated with 10(-10) M TNF-alpha in the presence of anti-IL-8 antibodies was, however, markedly and significantly higher than that of the controls (P<0.000). TNF-alpha induced the release of IL-8 (P<0.01) and IL-6 (P<0.05) from the duodenal explants. TNF-alpha and IL-8 are potent mitogens to human small intestinal crypts. The mitogenic action of TNF-alpha is primarily a direct effect of the cytokine and only to a minor extent mediated by a secondary production of IL-8 in the duodenal explant. Our findings indicate that TNF-alpha and IL-8 may participate in the regulation of cell proliferation in the human small intestinal epithelium.

Interleukin 8 and vascular endothelial growth factor -- prognostic factors in human gastric carcinomas?

Gastric carcinoma cells express potent angiogenic factors including vascular endothelial growth factor (VEGF). We previously reported that interleukin-8 (IL-8) acts as an angiogenic factor for human gastric carcinomas. More recently, we found that IL-8 upregulates matrix metalloproteinase-9 (MMP-9) expression and increases invasive activity of gastric carcinoma cells. The purpose of this study was to determine whether the expression of IL-8 and VEGF correlates with clinicopathological parameters in human gastric carcinomas. IL-8 and VEGF expression levels were measured by an enzyme-linked immunosorbent assay (ELISA) in 56 gastric carcinomas and the surrounding normal mucosa. Macroscopic and histopathological tumour findings, presence of metastasis and prognosis were obtained from the patient records and endoscopic, surgical and pathological reports. IL-8 protein levels were higher in most neoplasms than in the corresponding normal mucosal tissue. In contrast, VEGF expression in the tumours was similar to that in normal mucosa. The IL-8 level in the neoplasms correlated significantly with the depth of invasion, venous invasion and lymphatic invasion. VEGF expression in the tumours correlated well with the depth of invasion and lymph node metastasis. No correlation between IL-8 and VEGF expression in the tumours was observed. The survival rates of patients with tumours displaying high IL-8 and VEGF expression levels were significantly lower (P<0.05) than those of patients with tumours displaying low IL-8 and VEGF expression. The results suggest that IL-8 and VEGF may be independent and important prognostic factors in human gastric carcinomas.

Differential regulation of chemokine production in human peritoneal mesothelial cells: IFN-gamma controls neutrophil migration across the mesothelium in vitro and in vivo

Leukocyte recruitment into the infected peritoneal cavity consists of an early, predominant polymorphonuclear leukocyte (PMN) influx and subsequent, prolonged mononuclear cell migration phase. Although chemokine secretion by resident peritoneal cells plays a primary role in mediating this migration, the mechanisms involved in controlling the switch in phenotype of cell infiltrate remain unclear. The present study investigates a potential role for the Th1-type cytokine IFN-gamma in the process of leukocyte recruitment into the peritoneal cavity. Stimulation of cultured human peritoneal mesothelial cells with IFN-gamma (1-100 U/ml) alone or in combination with IL-1beta (100 pg/ml) or TNF-alpha (1000 pg/ml) resulted in significant up-regulation of monocyte chemoattractant protein-1 and RANTES protein secretion. In contrast, IFN-gamma inhibited basal and IL-1beta-, and TNF-alpha-induced production of IL-8. The modulating effects of IFN-gamma on chemokine production occurred at the level of gene expression, and the degree of regulation observed was dependent on the doses of IL-1beta and TNF-alpha used. Analysis of the functional effects of IFN-gamma on IL-1beta-induced transmesothelial PMN migration with an in vitro human transmigration system and an in vivo murine model of peritoneal inflammation demonstrated that IFN-gamma was able to down-regulate PMN migration induced by optimal doses of IL-1beta. These effects were mediated in vivo via down-regulation of CXC chemokine synthesis. These findings suggest that IFN-gamma may play a role in controlling the phenotype of infiltrating leukocyte during the course of an inflammatory response, in part via regulation of resident cell chemokine synthesis.

Cooperation of interleukin-17 and interferon-gamma on chemokine secretion in human fetal intestinal epithelial cells

Interleukin (IL)-17 is a newly identified T cell-derived cytokine that can regulate the functions of a variety of cell types. In this study, we investigated the effects of IL-17 and interferon (IFN)-gamma on chemokine secretion in human fetal intestinal epithelial cells. IL-8 and monocyte chemoattractant protein (MCP)-1 secretion by the human fetal intestinal epithelial cell line, intestine-407, was evaluated by ELISA and Northern blot. The expression of IL-17 receptor (R) was analysed by a binding assay using [(125)I]-labelled IL-17. The activation of nuclear factor-kappa B (NF-kappa B), NF-IL6 and AP-1 was assessed by an electrophoretic gel mobility shift assay (EMSA). IL-17 induced a dose-dependent increase in IL-8 and MCP-1 secretion. The inducing effects of IL-17 on IL-8 and MCP-1 mRNA abundance reached a maximum as early as 3 h, and then gradually decreased. IL-17 and IFN-gamma synergistically increased IL-8 and MCP-1 secretion and mRNA abundance. IFN-gamma induced a weak increase in IL-17 R mRNA abundance, and incubation with IFN-gamma for 24 h enhanced [(125)I]-labelled IL-17-binding by 2.4-fold. IL-17 rapidly induced the phosphorylation and degradation of I kappa B alpha molecules, and the combination of IL-17 and IFN-gamma induced a marked increase in NF-kappa B DNA-binding activity as early as 1.5 h after the stimulation. Furthermore, this combination induced an increase in NF-IL-6 and AP-1 DNA-binding activity. In conclusion, it becomes clear that IL-17 is an inducer of IL-8 and MCP-1 secretion by human fetal intestinal epithelial cells. The combination of IL-17 with IFN-gamma synergistically enhanced chemokine secretion. These effects of IL-17 and IFN-gamma might play an important role in the inflammatory responses in the intestinal mucosa.

Cytokines: past, present, and future

This review provides an historical account of the discovery and development of cytokines. Cytokines are soluble extracellular proteins or glycoproteins that are crucial intercellular regulators and mobilizers of cells engaged in innate as well as adaptive inflammatory host defenses, cell growth, differentiation, cell death, angiogenesis, and development and repair processes aimed at the restoration of homeostasis. Although cytokines are occasionally produced constitutively, they are usually produced by virtually every nucleated cell type in response to injurious stimuli. Cytokines act on cells expressing complementary receptors. Cytokines have been assigned to various family groups based on the structural homologies of their receptors. This review shows how cytokine research evolved from phenomenological to molecular stages and from a focus on ligands to characterization of cytokine receptors. The advent of molecular biology, monoclonal antibodies, and microsequencing made it possible to obtain pure recombinant cytokine preparation for experimental and therapeutic applications. The development of targeted gene deletions revealed many cytokines to have unexpected pathophysiological functions. The identification of "virokines," homologues that mimic cytokine ligands and receptors, has provided impetus to the founding of biotechnology companies aimed at developing cytokine agonists and antagonists for therapeutic applications. The discipline of cytokinology is now endowed with several journals, multiple annual meetings, and many devoted investigators. The explosion in cytokine information over the past 40 years has been enormous and full of surprises. If past be prologue, with the advent of genomics and proteomics the future should witness even greater progress.

Evidence for epigenetic mechanisms that silence both basal and immune-stimulated transcription of the IL-8 gene

It is becoming increasingly clear that epigenetic silencing of gene transcription plays a critical role in the regulation of gene expression in many biological processes. Tight regulation of immunomodulatory substances that are important for the initiation of the inflammatory cascade, such as chemoattractive cytokines, is essential to prevent initiation of unrestrained immune activation. Using the Caco-2 intestinal cell line as a model, we reveal two distinctly different mechanisms by which the gene for the neutrophil chemoattractive cytokine IL-8 is silenced. Nuclear run-on studies, as well as stably transfected reporter and marked minigene constructs, demonstrate that cellular differentiation inhibits immune-activated transcription of the IL-8 gene, a mechanism that is dependent on histone deacetylase activity. Unexpectedly, this silencing mechanism does not involve previously described regulatory elements in the IL-8 promoter but rather cis-acting regions located at a distance from the IL-8 gene locus. Genomic elements distant to the immediate IL-8 locus are also required to silence aberrant basal transcriptional activity of the IL-8 promoter in the absence of immune activation. However, in this case, silencing occurs in a histone deacetylase-independent fashion. These findings were confirmed in transgenic mice in which, in the absence of these elements, aberrant IL-8 gene activity was present primarily in the intestinal tract. Epigenetic silencing of cytokine gene transcription through distant genomic elements is an important level of gene regulation that may be relevant to the pathogenesis of immunologic disease states.

Differential effects of TNF and LTalpha in the host defense against M. bovis BCG

Signaling via TNF receptor type 1 (TNFR1) was shown to be crucial in host defense against the intracellular pathogens L. monocytogenes, M. tuberculosis and M. bovis. To investigate the function of TNF and LTalpha in host defense against M. bovis, mice double deficient for TNF and LTalpha (TNF / LTalpha (- / -)), TNF / LTalpha (- / -) mice complemented with a murine LTalpha transgene (TNF(- / -)) and LTalpha (- / -) mice were infected with BCG and the ensuing pathology was investigated. Control mice showed a normal host defense with early clearance of bacteria. The granulomatous reaction in the liver was accompanied by recruitment of activated macrophages characterized by their acid phosphatase positivity and differentiation into epithelioid cells as well as a coordinated expression of proinflammatory transcripts. In contrast, TNF / LTalpha (- / -) mice showed no comparable recruitment of activated macrophages in the liver. Furthermore, these mice showed extensive necrotic pulmonary lesions with massive growth of acid fast bacilli. Reintroduction of LTalpha as a transgene into TNF / LTalpha (- / -) mice prolonged survival but did not restore resistance to BCG. This, at least partially protective role of LTalpha was further supported by data demonstrating that LTalpha -deficient mice as well were susceptible to BCG infection. In contrast to the deleterious effect of TNF / LTalpha deficiency in BCG infection, BCG-infected TNF / LTalpha (- / -) mice were tolerant to LPS-induced shock. These results demonstrate that TNF as well as LTalpha are involved in murine host defense against BCG and that absence of TNF / LTalpha protects BCG-infected mice from LPS mediated shock.

An anti-inflammatory drug, propagermanium, may target GPI-anchored proteins associated with an MCP-1 receptor, CCR2

Monocyte chemoattractant protein-1 (MCP-1) promotes the migration and activation of monocytes and plays a pivotal role in the development of chronic inflammation. Propagermanium (3-oxygermylpropionic acid polymer) has been used as a therapeutic agent against chronic hepatitis B in Japan. We report here that propagermanium specifically inhibits in vitro chemotactic migration of monocytes by MCP-1. Propagermanium did not inhibit binding of MCP-1 to a human monocytic cell line, THP-1 cells, or affect intracellular Ca(2+) mobilization or the cAMP concentration in MCP-1-treated THP-1 cells. The effect of propagermanium seems to require glycosylphosphatidylinositol (GPI)-anchored proteins, as cleavage of GPI anchors by phosphatidylinositol-phospholipase C (PI-PLC) eliminated the inhibitory activity of propagermanium. Anti-GPI-anchored protein antibodies, such as anti-CD55 and anti-CD59, reduced staining of C-C chemokine receptor 2 (CCR2) with an anti-CCR2 antibody against the N-terminus of CCR2 in a flow cytometric analysis, and these antibodies also selectively inhibited MCP-1-induced migration of THP-1 cells. Furthermore, under fluorescence microscopy, GPI-anchored proteins colocalized with CCR2 on THP-1 cells. These results suggest that propagermanium may target GPI-anchored proteins that are closely associated with CCR2 to selectively inhibit the MCP-1-induced chemotaxis, thus providing a mechanistic basis for the anti-inflammatory effects of the drug.

Expression of aminopeptidase N in human endometrium and regulation of its activity by estrogen

OBJECTIVES

To determine whether aminopeptidase N (APN) regulates the cycle-dependent bioavailability of interleukin-8 (IL-8) in the endometrium.

DESIGN

Prospective study.

SETTING

University medical center.

PATIENT(S)

Women without endometrial pathology from the proliferative (n = 25) or secretory (n = 18) phase of the menstrual cycle.

INTERVENTION(S)

We first immunolocalized APN in the endometrium using an anti-APN antibody. We then determined the regulation of APN kinetic activity by sex steroids in endometrial stromal cell cultures.

MAIN OUTCOME MEASURE(S)

Expression of APN in human endometrium throughout the menstrual cycle. Regulation of APN activity by estradiol and progesterone in cultured endometrial stromal cells.

RESULT(S)

Immunohistochemistry of endometrial sections revealed staining of endometrial stroma throughout the menstrual cycle. There was no detectable staining in glandular cells. The expression of APN as detected by immunohistochemistry was significantly lower in the early proliferative phase. In cultured cells, estradiol inhibited APN activity in a concentration-dependent manner. Progesterone did not have a significant effect.

CONCLUSION(S)

Stromal localization of APN in endometrium may explain the epithelial rather than stromal presence of IL-8 in vivo. Decreased expression of APN may increase IL-8 bioavailability thus contributing to angiogenesis and polymorphonuclear leukocyte chemotaxis in early proliferative phase.

Cell density regulates neutrophil IL-8 synthesis: role of IL-1 receptor antagonist and soluble TNF receptors

Although cytokine synthesis in polymorphonuclear leukocytes (PMN) was shown to be modulated by soluble mediators, the impact of microenvironmental conditions has not been elucidated. In this study, we investigated the effect of cell density on cytokine release from human neutrophils. PMN were cultured at various cell densities (10 x 10(6) PMN/ml; 60 x 10(6) PMN/ml), and LPS-induced release of cytokines was quantified by ELISA technique. Upon an increase in PMN density, secretion of the CXC chemokine IL-8 was progressively reduced. This effect was paralleled by a decrease in IL-8 mRNA. In contrast, TNF-alpha and IL-1beta rose proportionally with increasing cell density. The inhibition of IL-8 secretion was reproduced by conditioned media of PMN at high cell density, but was not affected by blocking beta(2) integrin-dependent adhesion. When analyzing the supernatant of LPS-challenged neutrophils, large amounts of soluble TNFRs p55 and p75 (sTNFRI, sTNFRII), and IL-1R antagonist (IL-1RA), rising constantly with the cell density, were detected. Interestingly, combined blocking of the bioactivities of these mediators completely restored neutrophil IL-8 secretion at high cell densities, with the anti-IL-1RA Ab being the more potent agent. Moreover, combined application of exogenous IL-1RA and sTNFRs to 10 x 10(6) PMN/ml reproduced the suppression of IL-8 generation. We conclude that neutrophil IL-8 synthesis is autoregulated, being suppressed under conditions of high cell density. IL-1RA and sTNFRs, accumulating under these circumstances, seem to be centrally involved in this regulatory mechanism by interfering with the IL-1beta- and TNF-alpha-dependent IL-8 generation. This feedback mechanism may control further neutrophil recruitment and activation in a neutrophil-rich environment, thereby preventing tissue destruction.

The 3'-untranslated region of human interleukin-8 mRNA suppresses IL-8 gene expression

Although adenosine/uridine (AU)-rich sequences in the 3'-untranslated region (UTR) of the interleukin-8 (IL-8) gene have been suggested to contribute to its post-transcriptional regulation, the molecular basis whereby this occurs still needs to be understood. To investigate the role of the 3'-UTR on human IL-8 gene regulation, chimeric reporter genes were generated by adding full length or differentially deleted 3'-UTR of the IL-8 gene to chloramphenicol acetyltransferase (CAT). Addition of the entire IL-8 3'-UTR markedly reduced CAT mRNA and protein expression in COS 7 cells. In a reporter gene study, IL-8 3'-UTR destabilized CAT mRNA, which was dependent on active transcription in COS 7 cells. A 357-base sequence (nucleotides (nt) 2387-2743 of genomic DNA) within 3'-UTR, designated e, suppressed CAT gene expression by accelerating CAT mRNA turnover. A 26-base AU-rich sequence (nt 2552-2577) within e, containing four AUUUA pentamers that form two UAUUUAUU and one UUAUUUAU octamers, did not suppress CAT gene expression. However, deletion of the AU-rich sequences attenuated the inhibitory effect of e on CAT gene expression. Elimination of the first 100 bases (nt 2386-2486) attenuated the potency of fragment e, but much weaker than elimination of the first 146 bases (nt 2387-2533). This study gives new insights in unravelling the molecular mechanisms involved in the post-transcriptional regulation of the IL-8 gene.

Synthesis of C-X-C and C-C chemokines by human peritoneal fibroblasts: induction by macrophage-derived cytokines

Leukocyte accumulation during peritonitis is believed to be controlled by chemotactic factors released by resident peritoneal macrophages or mesothelial cells. Recent data indicate, however, that in many tissues fibroblasts play a key role in mediating leukocyte recruitment. We have therefore examined human peritoneal fibroblasts (HPFBs) for the expression and regulation of C-X-C and C-C chemokines. Quiescent HPFBs secreted monocyte chemoattractant protein (MCP)-1 and interleukin (IL)-8 constitutively. This release could be dose-dependently augmented with the pro-inflammatory cytokines IL-1beta and tumor necrosis factor-alpha. Stimulated IL-8 production reached a plateau within 48 hours while MCP-1 continued to accumulate throughout 96 hours. Induction of IL-8 and MCP-1 synthesis by HPFBs was also triggered by peritoneal macrophage-conditioned medium. This effect was partly related to the presence of IL-1beta as demonstrated by IL-1 receptor antagonist inhibition. Pretreatment of HPFBs with actinomycin D or puromycin dose-dependently reduced cytokine-stimulated IL-8 and MCP-1 secretion, which suggested de novo chemokine synthesis. Indeed, exposure of HPFBs to IL-1beta and tumor necrosis factor-alpha produced a significant up-regulation of IL-8 and MCP-1 mRNA. This effect was associated with the rapid induction of nuclear factor-kappaB binding activity mediated through p65 and p50 subunits, and with a transient increase in the mRNA expression for RelB and inhibitory protein kappaB-alpha proteins. These data indicate that peritoneal fibroblasts are capable of generating large quantities of chemokines under a tight control of nuclear factor-kappaB/Rel transcription factors. Thus, peritoneal fibroblast-derived chemokines may contribute to the intraperitoneal recruitment of leukocytes during peritonitis.

Interleukin-8 expression in AIDS-associated lymphoma B-cell lines

Interleukin 8 (IL-8), a member of the CXC subfamily of chemokines, is a potent inflammatory cytokine produced by many cell types in response to several stimuli. In an attempt to determine whether human B-cell IL-8 functions as an autocrine growth factor, a wide panel of B-cell lines derived from patients with AIDS-associated B-cell lymphomas (AABCL) (n = 5) and from non-AABCLs (n = 8) was studied for expression of IL-8, IL-8 Receptor type A (IL-8R), and secretion of IL-8 protein. Using RT-PCR and Northern Blot analysis, we were able to observe IL-8 expression ubiquitously. However, IL-8R expression was seen only in EBV negative (4 out of 7) B-cell lines. EBV and HIV-1 activated B-cell line; HBL-1, was the major secretor of IL-8. Our results demonstrate that IL-8 is expressed in malignant B-cell phenotypes that correspond to a narrow window in the B-cell differentiation pathway (pre-B, early-B, and intermediate-B) as well as in normal CD19-enriched B-cells. Furthermore, IL-8 autocrine loops were not evident since IL-8R was detected only in cell lines that did not secrete IL-8 protein.

Suppression of superantigen-induced lung injury and vasculitis by preadministration of human urinary trypsin inhibitor

We examined whether the lung injury produced in rats by intraperitoneal injection of the superantigen, staphylococcal enterotoxin B (SEB), could be inhibited by intravenous preadministration of human urinary trypsin inhibitor (UTI), which exhibits multipotent inhibitory effects on serine proteinases such as plasmin, chymotrypsin, or human leukocyte elastase or cathepsin G, since preliminary experiments showed the ability of UTI to bind lipopolysaccharides and bacterial toxins. For ligand blotting analysis, four kinds of toxins were run on a slab gel and the binding of UTI to the toxins was visualized by immunoblotting. Lung tissue from 26 rats was used for immunohistochemistry using a mouse antirat CD 45 mAb and an antirat macrophage mAb. Lung tissue from 31 rats was used for measurement of myeloperoxidase activity before and after intraperitoneal injection of SEB, after infusion of PBS, UTI, PBS-SEB or UTI-SEB combination. Ten of the 26 rats described above were used for electron microscopy. Rat sera were used for measurement of TNF-alpha. Statistical analysis was performed using the Mann-Whitney U-test. Intraperitoneal injection of SEB caused an increase in the number of punctate areas of haemorrhage on the surface of the lung with time, and histological examination revealed lung injuries with different extents, vasculitis where inflammatory cells were concentrated, and infiltration of numbers of eosinophils into the alveolar septa. However, preadministration of UTI for rats markedly attenuated lung injury and vasculitis induced by intraperitoneal injection of SEB. This revealed, from a marked reduction in the number of inflammatory cells and the extent of injury, a marked inhibition of serum TNF-alpha production and reduction of myeloperoxidase content of rat lungs compared to controls. UTI may have defensive effects to infection by suppressing the early responses of stimulated cells to activated stimulus such as SEB as well as the release of stimulant-mediated cytokines via trapping of bacterial toxins.

Expression levels of genes that regulate metastasis and angiogenesis correlate with advanced pathological stage of renal cell carcinoma

We examined the expression levels of a number of metastasis-related genes to determine the relationship of these levels to the development of metastasis in renal cell carcinoma. Gene expression was examined in 46 formalin-fixed, paraffin-embedded, archival specimens of primary organ-confined, clear-cell, renal cell carcinoma from patients who had undergone radical nephrectomy. Twenty samples were from patients who did not have metastasis after a median of 48 months; 26 were from patients with either synchronous or metachronous metastases. Microvessel density was assessed by anti-CD-34 immunohistochemical analysis. The expression levels of basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), interleukin-8 (IL-8), matrix metalloproteinases (MMP)-2 and -9, and E-cadherin were examined at the periphery of the tumor by a colorimetric in situ mRNA. The expression levels of bFGF, VEGF, IL-8, MMP-2, and MMP-9 were significantly higher in primary renal tumors from patients with either synchronous or metachronous metastases than those who were disease-free at a median of 48 months of follow-up. Multivariate analysis of disease-free survival showed that the ratio of MMP-9 to E-cadherin (P = 0.012) and the expression level of bFGF expression (P = 0.045), were independent predictors for the development of metastases. The expression levels of bFGF, VEGF, and IL-8 did not correlate with microvessel density, which in itself was not a significant predictor of progression (P = 0.21). In summary, expression levels of genes that regulate metastasis angiogenesis can predict the metastatic potential in individual patients with organ-confined clear-cell renal carcinoma.

A potential role for interleukin-8 in the metastatic phenotype of breast carcinoma cells

This study shows a strong correlation between the metastatic potentials of breast carcinoma cell lines and their ectopic expression of interleukin-8 (IL-8). Correlations exist for both constitutive and induced levels of IL-8 released. A correlation was also observed between cell morphology, metastatic potential, and IL-8 profile. Metastatic lines are fusiform in appearance, whereas, nonmetastatic lines are epithelioid. The metastatic potential of two breast carcinoma lines was examined using an orthotopic model of spontaneous metastasis. Metastatic cells formed rapidly growing, poorly differentiated primary tumors that metastasized. Nonmetastatic cells formed rapidly growing differentiated primary tumors that did not produce detectable metastases. Comparison of IL-8 expression by the parental cells and cell cultures developed from primary and metastatic tumors, demonstrates that IL-8 released by cultured cells from the primary tumor is higher than that of the parental cells, and IL-8 released by cultured cells derived from the metastatic lung tumors is greater than that released by cultured cells derived from the primary tumor. These data demonstrate a strong correlation between the metastatic phenotype of a cell and its IL-8 expression, suggesting a role for IL-8 in promoting the metastatic potential of breast tumor cells.

Expression of interleukin-8 in human metastatic endometrial carcinoma cells and its regulation by inflammatory cytokines

In the present study, we analyzed the expression of a multifunctional cytokine, interleukin-8 (IL-8), in metastatic endometrial carcinoma cells. Our data demonstrate that human serous papillary endometrial adenocarcinoma (SPEC) and human endometrial adenocarcinoma (HEC) cells expressed steady-state IL-8-specific mRNA transcript and secreted IL-8 protein. The levels of IL-8 mRNA in SPEC-2 cells established from stage IV serous papillary adenocarcinoma were three-fold higher as compared to endometrial adenocarcinoma cells, HEC-1 A, established from stage IA endometrial cancer. Further, we observed higher levels of IL-8 mRNA and protein expression in the metastatic variants of SPEC-2 and HEC-1A cells as compared to the parent cell lines, demonstrating that IL-8 expression was associated with metastatic potential. Further, the treatment of endometrial carcinoma cells with inflammatory cytokines, IL-1beta and tumor necrosis factor-alpha (TNF-alpha), demonstrated that IL-1beta and TNF-alpha induced IL-8 expression in endometrial cancer cells. IL-1beta was a more potent inducer of IL-8 expression than TNF-alpha in our studies. These data demonstrate that constitutive and induced IL-8 expression in endometrial carcinoma cells might be an important regulatory mechanism of tumor growth and metastasis.

Evaluation of the cytokines interleukin 8 and epithelial neutrophil activating peptide 78 as indicators of inflammation in prostatic secretions

OBJECTIVES

Chronic prostatitis/chronic pelvic pain syndrome (CPPS) is a disorder characterized by pelvic pain and varying degrees of inflammation exhibited in expressed prostatic secretions (EPS). To provide objective parameters of inflammation, we measured the cytokines interleukin 8 (IL-8) and epithelial neutrophil activating peptide 78 (ENA-78) in EPS of healthy men, men with benign prostatic hyperplasia (BPH), men with bacterial prostatitis (BP), and men with chronic prostatitis/CPPS.

METHODS

Enzyme-linked immunosorbent assays of the EPS for IL-8 and ENA-78 were done in 63 men: control (n = 9), BPH (n = 6), BP (n = 3), inflammatory CPPS (National Institutes of Health [NIH] category IIIa) (n = 17), noninflammatory CPPS (NIH category IIIb) (n = 17), and asymptomatic inflammatory prostatitis (NIH category IV) (n = 11).

RESULTS

IL-8 was detectable in all patients, and ENA-78 was detectable in all except 2 patients (threshold of detection 10 pg/mL for IL-8, 15 pg/mL for ENA-78). Mean levels of IL-8 [ENA-78] were similar in control (3010 pg/mL [423 pg/mL]), BPH (3341 pg/mL [98 pg/mL]), and IIIb (2751 pg/mL [335 pg/mL]) groups. Both cytokine levels were higher in BP (11,175 pg/mL [13,761 pg/mL]), IIIa (10,418 pg/mL [2240 pg/mL]), and IV (8571 pg/mL [1865 pg/mL]) groups. A statistically significant difference between the control group versus BP, IIIa, and IV (P <0.05) groups was found for IL-8 but not for ENA-78.

CONCLUSIONS

IL-8 and ENA-78 are frequently elevated in the EPS of men with BP, CPPS IIIa, and asymptomatic inflammatory prostatitis category IV. These cytokines are direct mediators of leukocyte accumulation and activation at inflammatory sites and may be responsible, in part, for the presence of inflammatory reaction in the prostate.

Role of microtubules in LPS-induced macrophage inflammatory protein-2 production from rat pneumocytes

We have recently demonstrated that primary cultured rat pneumocytes produce macrophage inflammatory protein-2 (MIP-2) in response to lipopolysaccharide (LPS) stimulation. In this study, we found that brefeldin A, by blocking anterograde transport from the endoplasmic reticulum (ER) to the Golgi apparatus, decreased LPS-induced MIP-2 in the culture medium and increased its storage in cells. This suggests that MIP-2 is secreted via a pathway from the ER to the Golgi apparatus, a process commonly regulated by microtubules. We further found that LPS induced depolymerization of microtubules as early as 1 min after LPS stimulation, and it lasted at least for 4 h. Preventing depolymerization of microtubules with paclitaxel (Taxol; 10 nM to 10 microM) partially inhibited LPS-induced MIP-2 production, whereas the microtubule-depolymerizing agents colchicine (1-10 microM) and nocodazole (1-100 microM) increased LPS-induced MIP-2 protein production without affecting MIP-2 mRNA expression. These results suggest that in pneumocytes, LPS-induced microtubule depolymerization is involved in LPS-induced MIP-2 production and that secretion of MIP-2 from pneumocytes is via the ER-Golgi pathway.

Interleukin-8 messenger ribonucleic acid expression correlates with tumor progression, tumor angiogenesis, patient survival, and timing of relapse in non-small-cell lung cancer

Tumor-associated angiogenesis is important for tumor growth and metastasis. Interleukin (IL)-8 was recently reported to be an important angiogenic factor both in vitro and in vivo. In this study we evaluated, for the first time, IL-8 messenger RNA (mRNA) expression in non-small-cell lung cancer (NSCLC), using real-time quantitative reverse-transcription-polymerase chain reaction, and correlated IL-8 mRNA expression in tumor and nontumor lung samples from 58 patients with NSCLC (29 with squamous cell carcinoma and 29 with adenocarcinoma, of whom 20 had Stage I, 10 had Stage II, and 28 had Stage III disease) with these patients' clinicopathologic characteristics, angiogenesis, and outcome. IL-8 protein expression and tumor microvessel count (MC) were assessed immunohistochemically. IL-8 mRNA expression was significantly greater in tumor tissue; high expression was highly associated with tumor in advanced stages (p = 0.03), distant lymph node metastasis (p = 0.02), high tumor MC (> 123) (p = 0.00003), short survival (< 26 mo) (p < 0.00001), and early relapse (< 16 mo) (p < 0.00001). Tumor MC correlated strongly with IL-8 mRNA expression (r = 0.56, p < 0.001). Multivariate analysis showed IL-8 mRNA expression and intratumor MC to be the most important predictors of patient survival and relapse. Thus, in NSCLC, IL-8 mRNA expression is strongly associated with tumor progression, tumor angiogenesis, survival, and time to relapse, suggesting its use as a prognostic indicator.

Induction of angiogenesis by hyperplastic colonic mucosa adjacent to colon cancer

We determined whether hyperplastic mucosa adjacent to colon cancer contributes to neoplastic angiogenesis. Surgical specimens of human colon cancer (40 Dukes' stage B and 34 Dukes' stage C) were analyzed by immunohistochemistry for expression of proliferative and angiogenic molecules. The mucosa adjacent to Dukes' stage C tumors (but not Dukes' stage B tumors) had a higher Ki-67 labeling index and a higher expression of epidermal growth factor receptor and transforming growth factor-alpha than distant mucosa. The expression levels of vascular endothelial growth factor, basic fibroblast growth factor, interleukin-8, and the vascular density in the adjacent mucosa were similar to those in the tumor lesions and significantly higher than those in the distant mucosa. The expression of interferon-beta inversely correlated with the level of pro-angiogenic molecules and the vascular density. The injection of metastatic human colon cancer cells and murine colon cancer cells into the cecal wall of mice induced hyperplastic changes in the adjacent mucosa which expressed higher levels of epidermal growth factor receptor, basic fibroblast growth factor, and vascular endothelial growth factor, and lower levels of interferon-beta than did the control mucosa, which directly correlated with the degree of hyperplasia. These data suggest that metastatic human colon cancer cells can induce hyperplasia in the adjacent mucosa, which in turn produces angiogenic molecules that contribute to neoplastic angiogenesis.

Elevated serum and bronchoalveolar lavage fluid levels of interleukin 8 and granulocyte colony-stimulating factor associated with the acute chest syndrome in patients with sickle cell disease

The role of cytokines in the development of acute chest syndrome (ACS) in patients with sickle cell disease (SCD) was studied. Serum interleukin 8 (IL-8) levels were elevated in 14 episodes and undetectable in six out of 20 episodes of ACS in 19 patients with SCD. In contrast, IL-8 levels were undetectable in the sera of 29 control patients with SCD studied during routine clinic visits or hospitalization for vaso-occlusive crises. The differences in mean IL-8 levels and the proportion of patients with detectable levels between the two groups were highly significant (P < 0.0001 and 0.04 respectively). The mean IL-8 level in bronchial fluid samples from children with ACS was also significantly higher than that in sickle cell patients undergoing elective surgery (5500 +/- 1400 pg/ml vs. 1900 +/- 470 pg/ml, P = 0.03). Granulocyte colony-stimulating factor (G-CSF) (2000 +/- 1700 pg/ml) was present in five out of six samples of bronchial fluid, but not serum, from children with ACS. All but one of the patients with ACS studied were negative for the Duffy red cell antigen, which is a receptor that binds and inactivates IL-8 and other chemokines. These findings suggest that IL-8 and G-CSF may play a role in the development of the ACS and the complications associated with it.

Chemokines in nasal secretions of normal adults experimentally infected with respiratory syncytial virus

The goal of this study was to determine time courses of upregulation of several chemokines in nasal secretions after inoculation of human subjects with a low dose of live respiratory syncytial virus (RSV). Healthy, nonsmoking young adults were admitted to an inpatient clinical research unit. After baseline studies, subjects were nasally inoculated with approximately 10(3) plaque-forming units of RSV (strain A2), followed by daily nasal lavages. Nasal lavage fluid (NLF) was assayed for chemokines by specific ELISA. Of 10 subjects inoculated with RSV, 3 developed clinical symptoms of upper respiratory infection and also shed virus. Among infected subjects, there was a transient postinoculation increase in interleukin-8 (IL-8) in NLF to an average of 2.7-fold compared to baseline, followed by a prolonged increase (maximum mean 5.4-fold) during virus shedding. RANTES, MIP-1alpha, and MCP-1 all increased during virus shedding only (maximum mean increases of 5.3-fold, 13-fold, and 7.2-fold, respectively). Semiquantitative RT-PCR in brushed nasal epithelial cells on day 6 after inoculation suggested upregulation of RANTES, but not IL-8, mRNA during virus shedding. We conclude that chemokines IL-8, RANTES, MIP-1alpha, and MCP-1 are all increased in nasal secretions in human RSV infection at the time of virus shedding and symptomatic illness and that the epithelium lining the nasal turbinate contributes to the increase in RANTES.

Interleukin-8 fails to induce human immunodeficiency virus-1 expression in chronically infected promonocytic U1 cells but differentially modulates induction by proinflammatory cytokines

This study addresses the role of interleukin (IL)-8, a CXC-chemokine, the level of which is reported to be raised in the peripheral circulation of human immunodeficiency virus-1 (HIV-1)-infected individuals, during the induction of HIV-1 expression from latency and during cytokine-mediated HIV-1 up-regulation. IL-8 at the higher concentrations tested (> or = 100 ng/ml) was unable to induce HIV-1 expression in the chronically infected promonocytic U1 cell line, as measured by p24 antigen enzyme-linked immunosorbent assay (ELISA), whereas at lower concentrations of 1 and 10 ng/ml, constitutive HIV-1 expression was only marginally reduced. HIV-1 replication in acutely infected U937 cells was also significantly reduced by IL-8. The potent up-regulation of HIV-1 expression in U1 cells by tumour necrosis factor-alpha (TNF-alpha) remained unaffected by the addition of IL-8. HIV-1 induction by IL-1beta, IL-6 and TNF-beta, cytokines grouped here as intermediate HIV-1 inducers, was suppressed by IL-8 at concentrations of 1 and 10 ng/ml. However, IL-8 at 100 ng/ml did not significantly alter the effect of IL-1beta, synergized with IL-6 in enhancing, and marginally suppressed TNF-beta-induced HIV-1 expression. IL-8 suppressed granulocyte-macrophage colony-stimulating factor (GM-CSF) and enhanced interferon-gamma (IFN-gamma)-induced HIV-1 expression in a dose-dependent manner. Pretreatment of U1 cells with IL-8 did not alter the IL-8-mediated effects on cytokine-induced HIV-1 expression, suggesting that this chemokine exerts its effect at the time of HIV-1 induction or at a postinduction stage. Furthermore, IL-8 was itself induced by cytokines that up-regulate HIV-1 expression in U1 cells and the levels produced correlated directly with the levels of p24 antigen produced, suggesting common pathways for cytokine induction of both HIV-1 and IL-8. These results show that IL-8, typically a non-inducer, can differentially modulate HIV-1 expression in U1 cells and that this is dependent on the inducing cytokine and on the concentration of IL-8.

Keratinocyte-derived chemotactic cytokines: expressional modulation by nitric oxide in vitro and during cutaneous wound repair in vivo

Inhibition of inducible nitric oxide-synthase (iNOS) enzymatic activity during cutaneous wound repair leads to severely impaired tissue regeneration. To assess whether disturbed leukocyte infiltration might participate in impaired repair, we determined expressional kinetics of neutrophil-attracting macrophage inflammatory protein-2 (MIP-2), and monocyte-attracting macrophage chemoattractant protein-1 (MCP-1) using an excisional wound healing model in mice. MCP-1 was induced in epithelial keratinocytes upon wounding, and our data indicate that NO serves a negative regulatory role for MCP-1 expression in vivo, as clearly reduced numbers of wound margin keratinocytes associated with NO-deficient repair compensate for high MCP-1 expression levels observed during normal healing. MIP-2 expression was restricted to hair follicles which were not reduced in number during NO-deficient repair. In vitro studies confirmed a regulatory role of NO for keratinocyte-derived chemokine expression, as NO attenuated IL-1beta- and TNF-alpha-induced MCP-1 mRNA expression, whereas NO augmented IL-1beta-induced IL-8 (functional human homolog to murine MIP-2) mRNA expression in the human keratinocyte cell line HaCaT.

Differential display identification of 40 genes with altered expression in activated human smooth muscle cells. Local expression in atherosclerotic lesions of smags, smooth muscle activation-specific genes

Detailed knowledge on the molecular and cellular mechanisms that control (re)-differentiation of vascular smooth muscle cells (SMCs) is critical to understanding the pathological processes underlying atherogenesis. We identified by differential display/reverse transcriptase-polymerase chain reaction 40 genes with altered expression in cultured SMCs upon stimulation with the conditioned medium of activated macrophages. This set of genes comprises 10 known genes and 30 novel genes, which we call "smags" (for smooth muscle activation-specific genes). To determine the in vivo significance of these (novel) genes in atherogenesis, we performed in situ hybridization experiments on vascular tissue. Specifically, FLICE (Fas-associated death domain-like interleukin-1beta-converting enzyme)-like inhibitory protein (FLIP) is expressed in neointimal SMCs as well as in lesion macrophages and endothelial cells, whereas the expression of the novel genes smag-63, smag-64, and smag-84 is restricted to neointimal SMCs. Characterization of full-length smag-64 cDNA revealed that it encodes a novel protein of 66 amino acids. smag-82 cDNA comprises the complete, unknown, 3'-untranslated region of fibroblast growth factor-5. Collectively, our results illustrate the complex changes of SMC gene expression that occur in response to stimulation with cytokines and growth factors secreted by activated macrophages. Moreover, we identified interesting candidate genes that may play a role in the differentiation of SMCs during atherogenesis.

Autocrine growth effect of IL-8 and GROalpha on a human pancreatic cancer cell line, Capan-1

A human pancreatic cancer cell line, Capan-1, secretes the chemokines interleukin-8 (IL-8) and growth-related oncogene alpha (GROalpha). Capan-1 cells also express the chemokine receptor 2 (CXCR2), which is a Gialpha-protein coupled receptor. Growth of Capan-1 cells was inhibited when anti-IL-8 or anti-GROalpha monoclonal antibody was added into the culture medium. Pertussis toxin, which blocks Gialpha also demonstrated a growth-inhibitory effect on Capan-1 cells. These results indicated that IL-8 and GROalpha act on Capan-1 cells as growth factors in an autocrine manner through CXCR2.

Cytokine regulation of chemokine (IL-8, MCP-1, and RANTES) gene expression in human pancreatic periacinar myofibroblasts

BACKGROUND & AIMS

We have previously isolated and characterized human pancreatic periacinar myofibroblasts. In this study, to define the role of these cells in the pathogenesis of acute pancreatitis, we investigated chemokine expression in them.

METHODS

Secretion of chemokines (interleukin [IL]-8, monocyte chemoattractant protein [MCP]-1, RANTES, and MIP [macrophage inflammatory protein]-1alpha) was evaluated by ELISA, Northern blotting, and nuclear run-on assays. The activation of NF-kappaB and NF-IL6 was assessed by an electrophoretic gel mobility shift assay.

RESULTS

IL-8 and MCP-1 secretion was rapidly induced by both IL-1beta and tumor necrosis factor (TNF)-alpha. RANTES secretion was induced more slowly and was induced mainly by TNF-alpha. However, MIP-1alpha secretion was not induced by any stimuli. These responses were also observed at the messenger RNA level, and they were accompanied by an increase in transcriptional rate. The increase in transcriptional activation of chemokine genes correlated with the NF-kappaB and NF-IL6 activation. Furthermore, a blockade of NF-kappaB activation by PDTC and TPCK markedly reduced the IL-1beta- or TNF-alpha-induced chemokine gene expression.

CONCLUSIONS

Chemokine secretion is differentially regulated in pancreatic periacinar myofibroblasts, suggesting a role for these cells in mediating the infiltration and accumulation of inflammatory cells in the pancreas.

The expression of chemokine genes correlates with nuclear factor-kappaB activation in human pancreatic cancer cell lines

Chemokines may regulate the process of immune cell infiltration that is often found in pancreatic cancer. In this study, we investigated the secretion of the chemokines [interleukin (IL)-8, monocyte chemoattractant protein (MCP)-1, and RANTES (regulated on activation, normal T cell expressed and secreted)] in human pancreatic cancer cell lines. The chemokine secretion in three pancreatic cancer cell lines (PANC-1, MIA PaCa-2, and BxPC-3) was evaluated by enzyme-linked immunosorbent assay (ELISA) and Northern blot, and the activation of nuclear factor-kappaB (NF-kappaB) and NF-IL6 was assessed by an electrophoretic gel mobility shift assay (EMSA). Without any stimulation, IL-8 secretion was detected in all cell lines, and MCP-1 secretion was detected in PANC-1 and MIA PaCa-2 cells. However, RANTES secretion was not detected in all cells. The addition of IL-1beta and tumor necrosis factor (TNF)-alpha strongly enhanced IL-8, MCP-1, and RANTES secretion; these responses were observed at the mRNA level as well as at the protein level. IL-1beta and TNF-alpha induced a rapid activation of nuclear factor (NF)-kappaB in PANC-1 cells, and the increase in chemokine mRNA expression correlated with NF-kappaB activation. The activation of NF-IL6 was modest. A blockade of NF-kappaB activation by TPCK markedly reduced the IL-1beta- and TNF-alpha-induced chemokine gene expression. Our findings indicate that chemokines are produced by pancreatic cancer cells, and suggest that these factors may contribute to the accumulation of tumor-associated immune cells. In addition, the transcriptional activation of chemokine genes in pancreatic cancer cells may be closely associated with NF-kappaB activation.