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Biomedical subjects

N Mukaida

Publications and source records attributed to N Mukaida.

At least 145 records · Page 8Linked to original sources
PubMed1995

Monocyte chemoattractant protein-1 stimulates tumor necrosis and recruitment of macrophages into tumors in tumor-bearing nude mice: increased granulocyte and macrophage progenitors in murine bone marrow.

Monocyte chemoattractant protein-1 (MCP-1) belongs to the newly recognized "chemokine" superfamily of activation-inducible cytokines. We report here that MCP-1 gene-transferred mouse myeloma cells modulate tumor necrosis in myeloma-bearing nude mice. We established an MCP-1-producing myeloma cell line (X63-MCP-1) by transfection with human MCP-1 cDNA as well as interleukin-8-producing X63 cells (X63 IL-8). Each cell line showed the same growth characteristics in vitro, and 1 x 10(7) cells per mouse were injected into the peritoneal cavity resulting in the formation of tumors. Hematologic studies, including peripheral white blood cell counts and differentiation, showed no differences among the groups. They formed tumors in the same manner, which we observed from weeks 2.5 to 9. MCP-1 mice showed more tumor necrosis and infiltration of the macrophages into the tissue surrounding the tumor. In situ hybridization, using a partial cDNA as a probe, showed that macrophages contained MCP-1 mRNA. Bone marrow cell colony-forming assay showed a greater number of both granulocyte and macrophage colonies in MCP-1 mouse femur than in those of controls or interleukin-8 mice. MCP-1 has no direct stimulatory activity on stem cells, but longer exposure to MCP-1 in vivo might stimulate both granulocyte and macrophage progenitors and recruitment of macrophages into tumors, and it might explain the antitumor activity of macrophages in tumor-bearing nude mice.

Animals↗
PubMed1995

[Primary immunodeficiency diseases].

A substantial proportion of patients with primary immunodeficiency diseases develop tumors, particularly those of lymphoreticular system caused by Epstein-Barr virus (EBV). Primary immunodeficiency renders patients susceptible to EBV by reducing immune reactions and surveillance abilities against the virus or inducing overreaction of the responding cells to the antigens. Recent progress in molecular biology has unraveled the genes responsible for several types of primary immunodeficiency diseases. The cloning of the ATM gene demonstrated that the mutations in this gene were observed in the members of all the families affected with ataxia telangiectasia (AT), indicating the crucial role of this gene in the pathogenesis of AT. The protein encoded by the ATM gene shows a high sequence homology with several proteins which are presumed to be involved in the regulation of the cell cycle transition. Accumulating evidence indicates that AT-derived cells are sensitive to irradiation due to the abnormalities in p53-dependent cell cycle arrest at G1 phase. Thus, the ATM product may regulate the cell cycle at G1 phase in a p53-dependent manner and the defect of the gene may lead to the accumulation of cells with DNA damages, thereby causing malignant transformation.

Animals↗
PubMed1995

Expression of inflammatory cytokines and adhesion molecules in haemodialysis-associated amyloidosis.

BACKGROUND: The occurrence of various arthropathies including carpal-tunnel syndrome (CTS) in dialysis-associated amyloidosis, a condition caused by the deposition of beta 2 microglobulin (beta 2MG), has been emphasized for several years. We attempted to analyse the pathogenesis of CTS in haemodialysis-associated amyloidosis (HA). METHODS: The expression of cell adhesion molecules and inflammatory cytokines in tenosynovial tissues was determined by using both reverse-transcriptase polymerase chain reaction (RT-PCR) and immunostaining. RESULTS: There was a marked expression of ICAM-1, VCAM-1, E-selectin mRNAs together with increased mRNA expression of inflammatory cytokines (IL-1 beta, TNF alpha, IL-6 and MCP-1) in proliferating synovial tissues. ICAM-1 was expressed not only on vascular endothelial cells, but also on synovial cells. In contrast, both VCAM-1 and E-selectin were exclusively expressed on endothelial cells. Mononuclear cells bearing CD13, CD14, CD33 and HLA-DR with macrophage-like morphology were accumulated in the perivascular area and expressed VLA-4, LFA-1 and Mac-1. Moreover, synovial lining cells, vascular endothelial cells and infiltrated mononuclear cells expressed chemokines such as MCP-1 and MIP-1 alpha. CONCLUSIONS: These data suggest that upregulated expression of inflammatory cytokines and adhesion molecules promotes activation and infiltration of macrophages causing CTS in haemodialysis-associated amyloidosis patients.

Amyloidosis↗
PubMed1994

Prevention of proteinuria by the administration of anti-interleukin 8 antibody in experimental acute immune complex-induced glomerulonephritis.

Glomerular infiltration by neutrophils is a hallmark of acute glomerulonephritis. The pathophysiological role of interleukin 8 (IL-8), a potent neutrophil chemotactic cytokine (chemokine), was explored in an animal model of acute immune complex-mediated glomerulonephritis by administering a neutralizing antibody against IL-8. Repeated injection of bovine serum albumin (BSA) into rabbits caused the deposition of immune complexes consisting of BSA and rabbit IgG in glomeruli. Histological analyses revealed a small but significant number of neutrophils in glomeruli and the fusion of epithelial cell foot processes. Concomitantly, urinary levels of protein and albumin increased markedly (3.20 +/- 0.97 and 1.39 +/- 0.53 mg/h, respectively) compared with those of untreated animals (0.77 +/- 0.21 and 0.01 +/- 0.01 mg/h, respectively). Anti-IL-8 antibody treatment decreased the number of neutrophils in glomeruli by 40% and dramatically prevented the fusion of epithelial cell foot process. Furthermore, treatment with anti-IL-8 antibody completely normalized the urinary levels of protein and albumin (0.89 +/- 0.15 and 0.02 +/- 0.01 mg/h, respectively). These results indicated that IL-8 participated in the impairment of renal functions in experimental acute immune complex-mediated glomerulonephritis through activating as well as recruiting neutrophils.

Acute Disease↗
PubMed1994

Cloning of a cDNA encoding a mouse homolog of the interleukin-8 receptor.

A mouse cDNA library was screened using a DNA fragment generated by polymerase chain reaction (PCR) with oligodeoxyribonucleotide primers which were derived from the conserved sequences in cDNAs encoding the human and rabbit interleukin-8 receptors (hIL-8R and rIL-8R). A novel cDNA was obtained encoding 359 amino acids (aa) with seven putative transmembrane portions similar to hIL-8R and rIL-8R. Its aa sequence shows 64 and 69% homology to those of type-1 and type-2 hIL-8R, respectively. COS-7 cells transfected with the isolated cDNA in a mammalian expression vector bind IL-8, but do not bind a related protein, monocyte chemotactic and activating factor, suggesting that the isolated cDNA encodes the mouse homolog of IL-8R. Northern blot analysis showed that mRNA of this clone was highly expressed in mouse peritoneal neutrophils, and the single band was observed in Southern blotting analysis on mouse genomic DNA digested with HindIII or KpnI, suggesting that this is a single-copy gene.

Amino Acid Sequence↗
PubMed1994

Novel mechanism of glucocorticoid-mediated gene repression. Nuclear factor-kappa B is target for glucocorticoid-mediated interleukin 8 gene repression.

A glucocorticoid, dexamethasone, inhibited the production of a leukocyte chemotactic cytokine, interleukin 8 (IL-8), as well as mRNA expression by a glioblastoma cell line, T98G, stimulated with interleukin 1 (IL-1). Dexamethasone also inhibited IL-8 promoter-driven chloramphenicol acetyltransferase (CAT) activities induced by IL-1, suggesting that dexamethasone inhibited IL-8 production mainly at the transcriptional level. Moreover, CAT assay revealed that the nuclear factor-kappa B (NF-kappa B) binding site was the crucial cis-element required for conferring IL-1 responsiveness in conjunction with the CCAAT enhancer binding protein/nuclear factor-IL-6 (NF-IL6) and/or the AP-1 binding site(s). Mutation of either the AP-1 or NF-IL6 binding site did not abolish IL-8 gene repression by dexamethasone, suggesting that these sites were not targets for dexamethasone. Trimerized kappa B sequence in the IL-8 gene was enough for conferring the induction by IL-1 and inhibition by dexamethasone of CAT activity. Finally, dexamethasone diminished the IL-1-induced formation of NF-kappa B complexes, which were identified immunochemically to consist of p50 and p65, without reducing the amount of translocated factors. Collectively, dexamethasone interfered with the binding of the most essential transcription factor, NF-kappa B, to its cognate cis-element, thereby suppressing the transcription of IL-8 gene.

Amino Acid Sequence↗
PubMed1994

The interleukin-8 AP-1 and kappa B-like sites are genetic end targets of FK506-sensitive pathway accompanied by calcium mobilization.

FK506, an immunosuppressant, inhibits the production of several cytokines in T lymphocytes. We observed that FK506 suppressed the transcription of a chemotactic cytokine, interleukin-8 (IL-8) in a human T cell line, Jurkat cells, activated by phorbol 12-myristate 13-acetate (PMA) and calcium (Ca2+) ionophore (ionomycin). By deleted and mutated analysis of the IL-8 promoters, the AP-1 and kappa B-like sites were identified as the responsive elements for PMA and ionomycin. FK506 suppressed the transcriptions through the AP-1 or kappa B-like sites induced by PMA plus Ca(2+)-mobilizing agents, but not those induced by Ca(2+)-independent stimuli. In gel retardation analysis, FK506 had little effect on the binding to the AP-1 site of PMA/ionomycin-induced nuclear factors, which were recognized with anti-JunD or c-Fos antibody. In contrast, FK506 or EGTA (Ca2+ chelator) similarly affected the formation of kappa B-like site binding complexes, which were not recognized by any antibodies against the human Rel family proteins (c-Rel, p65, p50, and p49). Furthermore, we confirmed the previous report that FK506 suppressed the PMA/ionomycin-induced activation through authentic kappa B site of immunoglobulin (Ig) gene, to which NF-kappa B binding was also decreased by FK506, indicating that both IL-8 kappa B-like site and Ig kappa B site are FK506-sensitive in spite of the difference of binding factors. Our results indicate that not only the reported IL-2 NF-AT and NFIL-2A sites and Ig kappa B site, but also the IL-8 AP-1 and kappa B-like sites are terminals of FK506-sensitive pathway involving Ca2+ mobilization.

Base Sequence↗
PubMed1994

Detection of urinary interleukin-8 in glomerular diseases.

To clarify the mechanism of neutrophil infiltration in glomerulonephritis, both urinary and plasma levels of a potent neutrophil chemotactic cytokine, interleukin-8 (IL-8), were measured in 40 healthy volunteers and 96 patients with various renal diseases. The plasma IL-8 levels were less than 16 pg/ml. The urinary IL-8 levels were elevated in several renal diseases including IgA nephropathy (17 of 43), acute glomerulonephritis (4 of 6), lupus nephritis (11 of 15), purpura nephritis (2 of 4), membranoproliferative glomerulonephritis (1 of 1), and cryoglobulinemia (2 of 2). IL-8 was detected immunohistochemically in diseased glomeruli, suggesting its local production. Elevated urinary IL-8 levels during the acute phase or exacerbations were found to be decreased during spontaneous or steroid pulse therapy-induced convalescence in all patients examined. The urinary IL-8 levels were higher in patients with glomerular leukocyte infiltration than in those without infiltration. Collectively, local production of IL-8 in diseased glomeruli might be involved in the pathogenesis of the glomerular diseases and measurement of IL-8 in the urine might be useful for monitoring the glomerular diseases.

Acute Disease↗
PubMed1994

Selective expression of monocyte chemotactic and activating factor/monocyte chemoattractant protein 1 in human blood monocytes by Mycobacterium tuberculosis.

Neutrophils are the predominant leukocyte population in acute inflammation. Granulomatous inflammation such as tuberculosis is a specific type of chronic inflammation characterized by the predominant accumulation of macrophages. To clarify the mechanism of cellular recruitment in inflammation, the expression of chemokines, interleukin-8 and monocyte chemotactic and activating factor (MCAF)/monocyte chemoattractant protein 1 (MCP-1), was examined in human blood monocytes in response to lipopolysaccharide of Escherichia coli, which could induce acute inflammation, or purified protein derivative (PPD) or Mycobacterium tuberculosis, which could provoke chronic inflammation. Monocytes stimulated with PPD or M. tuberculosis expressed low levels of antigenic interleukin-8 but high levels of MCAF/MCP-1 compared with monocytes stimulated with lipopolysaccharide. Northern blot analysis showed the early induction of interleukin-8 mRNA and the delayed expression of MCAF/MCP-1 mRNA in response to PPD or M. tuberculosis. Thus, the disparate expression of chemokines may contribute to the cellular recruitment in acute and chronic inflammations.

Adult↗
PubMed1994

Protection against lethal bacterial infection in mice by monocyte-chemotactic and -activating factor.

Chemotactic factors regulate the recruitment of neutrophils, lymphocytes, or monocytes-macrophages to infectious and inflammatory sites. The purpose of this study was to determine whether monocyte-chemotactic and -activating factor (MCAF [MCP-1], a JE gene product) also influences the host defense mechanism against microbial infection. We evaluated the effect of recombinant human MCAF on the survival rate of mice systemically infected with Pseudomonas aeruginosa or Salmonella typhimurium. The administration of 2.5 micrograms of MCAF 6 h before infection completely protected the mice from lethal infection. Mice with cyclophosphamide-induced leukopenia exhibiting increased susceptibility to P. aeruginosa were also endowed with resistance by the same dose of MCAF. Administration of MCAF at -6 h was critical, since MCAF given either earlier or later than -6 h failed to rescue mice from lethal infection. The in vivo effect on the survival of mice paralleled the reduced recovery of viable P. aeruginosa or S. typhimurium from the peritoneal cavity, i.e., the number of recovered bacteria from the MCAF (2.5 micrograms per mouse)-treated mice was reduced to less than 2% of control mice for P. aeruginosa and 4% of control mice for S. typhimurium at 24 h. Since MCAF exhibited chemotaxis on murine macrophages as well as enhanced phagocytosis and killing of bacteria in vitro, the activation of macrophages, followed by the recruitment into the peritoneal cavity, is responsible for eliminating bacteria and thus enhancing the survival rate.

Animals↗
PubMed1994

Enhancement human cytomegalovirus replication in a human lung fibroblast cell line by interleukin-8.

We examined the effects of interleukin-8 (IL-8) on cytomegalovirus (CMV) replication in human fibroblasts. Exposure of fibroblasts to IL-8 augmented both infectious virus production and replication of CMV, with concomitant increases in the levels of both the transcript of the CMV pp71 genome and the synthesis of the CMV late antigen. We also found that CMV selectively induced transcripts of the IL-8 type 1 receptor in fibroblasts. These results suggest that IL-8 also contributes to inflammatory diseases by enhancing CMV replication and that CMV regulates its production through induction of IL-8 receptor.

Cell Line↗
PubMed1994

Transcriptional inhibition of the interleukin-8 gene by interferon is mediated by the NF-kappa B site.

The cytokine interleukin-8 (IL-8) is an important mediator of neutrophil, lymphocyte, and basophil chemotaxis and activation. Earlier we demonstrated that beta interferon (IFN-beta) can inhibit tumor necrosis factor (TNF)-induced IL-8 gene expression at the transcriptional level, apparently by a novel mechanism. To define the cis-acting elements and trans-acting factors involved in this inhibition, DNA constructs containing portions of the 5'-flanking region of the IL-8 gene were linked to the chloramphenicol acetyltransferase (CAT) reporter gene and transfected into human diploid FS-4 fibroblasts. The region spanning positions -98 to +44 was sufficient to confer both inducibility by TNF and inhibition by simultaneous treatment with IFN-beta. Inhibition of TNF- or IL-1-induced CAT activity by IFN-beta or IFN-alpha was also observed when a DNA fragment containing only the NF-IL-6 and NF-kappa B sites (positions -94 to -70) was placed upstream of the homologous or a heterologous minimal promoter. A construct containing three copies of the NF-kappa B element in front of the CAT gene also was inducible by TNF, and this stimulatory effect too was inhibited by IFN-beta, indicating that the NF-kappa B element is sufficient to confer inhibition by IFN-beta. This inhibitory effect was specific for the NF-kappa B site of the IL-8 gene since it was less marked with constructs containing three copies of the NF-kappa B site from the HLA-B7 gene. Gel shift assays with a probe containing the NF-kappa B and NF-IL-6 binding sites of the IL-8 gene (positions -101 to -63) showed that IFN-beta treatment did not block the activation of NF-kappa B proteins or their ability to bind to the NF-kappa B site. However, nuclear extracts from cells treated with TNF in the presence of IFN-beta gave rise to an additional band that appears to contain protein components from the NF-kappa B and NF-IL-6 families. NF-kappa B site-mediated suppression of IL-8 gene expression by IFN-beta represents a hitherto unknown mechanism and target of IFN action.

Base Sequence↗
PubMed1994

Molecular mechanism of interleukin-8 gene expression.

A potent leukocyte chemotactic and activating cytokine, interleukin-8 (IL-8), is produced by numerous types of cells in response to inflammatory stimuli. Accumulating evidence indicate that the transcription of IL-8 gene requires the activation of either the combination of NF-kappa B and AP-1 or that of NF-kappa B and NF-IL6, depending on the type of cells. Alternatively, the activation of NF-kappa B is indispensable for IL-8 gene activation in any types of cells examined. On the other hand, an immunosuppressant, FK506, and a glucocorticoid inhibit the gene transcription as well as the production of IL-8. Molecular analyses of IL-8 gene repression by these agents revealed that both affected the activity of the transcription factor(s) bound to the NF-kappa B site, albeit in different ways, thereby suppressing IL-8 gene transcription. Collectively, IL-8 production seems to be controlled mainly at the activation step of the transcription factor(s) bound to the NF-kappa B site.

CCAAT-Enhancer-Binding Proteins↗
PubMed1994

Essential involvement of interleukin-8 (IL-8) in acute inflammation.

Neutrophil infiltration into inflammatory sites is one of the hallmarks of acute inflammation. Locally produced chemotactic factors are presumed to mediate the sequence of events leading to the infiltration at inflammatory sites. Interleukin-8 (IL-8), a novel leukocyte chemotactic activating cytokine (chemokine), is produced by various types of cells upon stimulation with inflammatory stimuli and exerts a variety of functions on leukocytes, particularly, neutrophils in vitro. However, no definitive evidence has been presented on its role in recruiting and activating neutrophils in the lesions of various types of inflammatory reactions. We administered a highly specific neutralizing antibody against IL-8 in several types of acute inflammatory reactions, including lipopolysaccharide (LPS)-induced dermatitis, LPS/IL-1-induced arthritis, lung reperfusion injury, and acute immune complex-type glomerulonephritis. Anti-IL-8 treatment prevented neutrophil-dependent tissue damage as well as neutrophil infiltration in these conditions. These results suggest that IL-8 plays a causative role in acute inflammation by recruiting and activating neutrophils.

Animals↗
PubMed1994

Essential involvement of interleukin-8 in neutrophil recruitment in rabbits with acute experimental arthritis induced by lipopolysaccharide and interleukin-1.

Rheumatoid arthritis and related inflammatory joint diseases are characterized by massive infiltration of polymorphonuclear cells (PMN) into inflamed joints. Interleukin-8 (IL-8) has recently been identified as a leukocyte chemotactic and activating factor produced by activated tissue cells as well as monocytes/macrophages. Examination was made of the involvement of IL-8 in acute arthritis induced by injecting lipopolysaccharide (LPS) or interleukin-1 alpha (IL-1 alpha) into the joints of rabbits. The neutralizing antibody to rabbit IL-8 blocked almost completely the infiltration of PMN into the joints and provided protection from damage to tissue in the early phase of inflammation induced by LPS or IL-1 alpha. Mononuclear cell infiltration observed later was not inhibited by this antibody. This is the first paper to clearly demonstrate that IL-8 is an essential and major mediator determining whether PMN infiltration will occur in the early phase of experimental acute arthritis.

Animals↗
PubMed1993

Transcription factors NF-IL6 and NF-kappa B synergistically activate transcription of the inflammatory cytokines, interleukin 6 and interleukin 8.

Single binding sites for transcription factors NF-IL6 and NF-kappa B are present in the promoter of the interleukin (IL) 6 gene. Previous studies of internally deleted promoter mutants demonstrated that these two sites are important for the transcriptional regulation of this gene. In this report, we describe the synergistic activation of the IL-6 promoter by transcription factors NF-IL6 and NF-kappa B. Cotransfection of NF-IL6 with the NF-kappa B p65 subunit resulted in strong synergistic activation of an IL-6 promoter-reporter construct. Both the NF-IL6 and NF-kappa B binding sites in the IL-6 promoter were required for synergistic activation. Similar synergistic activation was observed in the IL-8 promoter, which also contains both NF-IL6 and NF-kappa B binding sites. Furthermore, we demonstrated that NF-IL6 and the NF-kappa B p65 subunit directly associated via the basic leucine-zipper domain of NF-IL6 and the Rel homology domain of p65. Since the promoters of many other genes involved in the inflammatory and acute-phase responses also contain binding sites for NF-IL6 and NF-kappa B, the cooperation between these two factors may have an important role in these responses. We also discuss the possible interplay between various viral gene products and these two factors in the process of viral infection and constitutive cytokine production.

Base Sequence↗