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1.  Transforming growth factor-β stimulates the expression of eotaxin/CC chemokine ligand 11 and its promoter activity through binding site for nuclear factor-κB in airway smooth muscle cells 
Summary
Background
Chemokines ligands of CCR3 including eotaxin/CC chemokine ligand 11 (CCL11) may contribute to the pathogenesis of asthma. These chemokines and a growth factor (TGF-β) may be involved in the process of airway remodelling.
Objective
We analysed the effects of TGF-β on the expression of CCR3 ligands in human airway smooth muscle (HASM) cells and investigated the mechanisms.
Methods
HASM cells were cultured and treated with TGF-β and Th2 cytokines IL-4 or IL-13. Expression of mRNA was analysed by real-time PCR. Secretion of CCL11 into the culture medium was analysed by ELISA. Transcriptional regulation of CCL11 was analysed by luciferase assay using CCL11 promoter-luciferase reporter plasmids.
Results
IL-4 or IL-13 significantly up-regulated the expression of mRNAs for CCL11 and CCL26. TGF-β alone did not increase the expression of chemokine mRNAs, but enhanced the induction of only CCL11 by IL-4 or IL-13 among CCR3 ligands. Activity of the CCL11 promoter was stimulated by IL-4, and this activity was enhanced by TGF-β. Activation by IL-4 or IL-4 plus TGF-β was lost by mutation of the binding site for signal transducers and activators of transcription-6 (STAT6) in the promoter. Cooperative activation by IL-4 and TGF-β was inhibited by mutation of the binding site for nuclear factor-κB (NF-κB) in the promoter. Pretreatment with an inhibitor of NF-κB and glucocorticoid fluticasone propionate significantly inhibited the expression of CCL11 mRNA induced by IL-4 plus TGF-β, indicating the importance of NF-κB in the cooperative activation of CCL11 transcription by TGF-β and IL-4.
Conclusion
These results indicate that Th2 cytokines and TGF-β may contribute to the pathogenesis of asthma by stimulating expression of CCL11. The transcription factors STAT6 and NF-κB may play pivotal roles in this process.
doi:10.1111/j.1365-2222.2010.03474.x
PMCID: PMC3712283  PMID: 20214667
airway smooth muscle cells; asthma; CCL11; eotaxin; NF-κB; TGF-β
2.  Characterisation of cartilage intermediate layer protein (CILP)-induced arthropathy in mice 
Annals of the Rheumatic Diseases  2004;63(3):252-258.
Objectives: To characterise cartilage intermediate layer protein (CILP)-induced arthropathy in mice.
Methods: The first and second halves of the nucleotide triphosphate pyrophosphohydrolase (NTPPHase) non-homologous region of human CILP were prepared as recombinant proteins (C1 and C2, respectively), including three overlapping fragments of C2 (C2F1, C2F2, and C2F3). C57BL/6 mice were immunised with these proteins to induce arthritis. In addition, a separate group of mice were immunised repeatedly with the mixture of C1 and C2 to see the effect of chronic immunisation. Arthritis developed in the mice, and cellular and humoral immune responses against CILP were analysed.
Results: Immunisation with C2 and with the mixture C2F1/C2F2/C2F3 caused the severest arthritis to develop in mice. Immunisation with one of C1, C2F1, C2F2, or C2F3 caused milder arthritis, even though each of the fragments carried T cell epitopes. Immunisation either with C1 or C2 alone evoked cellular and humoral immune responses to both the C1 and C2 proteins. Further, the repeated immunisation with the C1/C2 mixture caused tendon calcification and bone irregularity, together with decreased NTPPH activity.
Conclusions: The results show that multiple T cell epitopes are needed for the development of CILP-induced arthritis, and present the characteristic new model of mild arthropathy accompanied by extra-articular calcifications. An immune response to putative murine CILP/NTPPH may be involved in the ectopic calcifications in the arthritic mice.
doi:10.1136/ard.2003.008045
PMCID: PMC1754905  PMID: 14962958
4.  Effect of IL15 on T cell clonality in vitro and in the synovial fluid of patients with rheumatoid arthritis 
Annals of the Rheumatic Diseases  2000;59(9):688-694.
OBJECTIVE—Recent studies have suggested that interleukin (IL) 15 induces T cell accumulation in synovial lesions of rheumatoid arthritis (RA). This study aimed at determining whether this cytokine could explain in vivo T cell clonality in RA.
METHODS—Peripheral blood mononuclear cells (PBMC) from patients with RA were stimulated in vitro with IL15 or IL2. After isolation of mRNA from stimulated cells and synovial T cells, genes coding the V-D(N)-J (CDR3) region of T cell receptor β chains were amplified by a reverse transcriptase polymerase chain reaction. A single strand conformation polymorphism analysis was used to detect the clonotype(s) of accumulating T cells. Nucleotide and amino acid sequencing was also performed.
RESULTS—Stimulation of PBMC with IL15 resulted in oligoclonal expansion of T cells. However, IL15 induced clones from PBMC were mostly different from the dominantly expanding T cell clones in synovial fluid. Furthermore, IL15 and IL2 responding clones were only partially identical.
CONCLUSIONS—Although IL15 results in clonal accumulation of T cells, T cell clonality in rheumatoid joints could not be explained by the effect of IL15 alone. The results indicated the requirement of other factor(s), in addition to IL15, in the pathological process affecting RA joints. The results also suggested different responses by each T cell clone to IL15 or IL2.


doi:10.1136/ard.59.9.688
PMCID: PMC1753264  PMID: 10976081
5.  Characterisation of T cell clonotypes that accumulated in multiple joints of patients with rheumatoid arthritis 
Annals of the Rheumatic Diseases  1999;58(9):546-553.
OBJECTIVE—To investigate whether identical T cell clonotypes accumulate in multiple rheumatoid joints, the clonality of T cells that had infiltrated into synovial tissue (ST) samples simultaneously obtained from multiple joints of patients with rheumatoid arthritis (RA) was analysed.
METHODS—T cell receptor (TCR) β gene transcripts, amplified by reverse transcription-polymerase chain reaction from ST and peripheral blood lymphocytes of five RA patients, were subjected to single strand conformation polymorphism analysis and DNA sequencing.
RESULTS—Approximately 40% of accumulated T cell clonotypes found in one joint of a patient were found in multiple joints in the same patient. Furthermore, identical amino acid sequences were found in TCR β junctional regions of these clonotypes from different patients with at least one HLA molecule match.
CONCLUSIONS—The T cell clonotypes accumulating in multiple rheumatoid joints may be involved in the perpetuation of polyarthritis by reacting to antigens common to these multiple joints.


PMCID: PMC1752942  PMID: 10460187
6.  Suppressive effects of anti-allergic agent suplatast tosilate (IPD-1151T) on the expression of co-stimulatory molecules on mouse splenocytes in vivo. 
Mediators of Inflammation  2001;10(6):333-337.
The effects of IPD-1151T on the expression of co-stimulatory molecules, CD40, CD80 and CD86, were investigated in vivo using mice with allergic disorders. BALB/c mice were immunized intraperitoneally with two doses of dinitrophenylated ovalbumin (DNP-OVA) at 1-week intervals. These mice then were treated intraperitoneally with 100 microg/kg of IPD-1151T once a day for 14 days, starting 7 days after the first immunization. On day 21, some mice were challenged intraperitoneally with DNP-OVA and the other mice were not challenged. All mice were autopsied on day 22 and assayed for immunoglobulin E, interleuken (IL)-4 and IL-5 productions following DNP-OVA immunization. The intraperitoneal treatment with IPD-1151T strongly suppressed immunoglobulin E contents in serum, which were enhanced by DNA-OVA immunization. IPD-1151T also caused a decrease in both IL-4 and IL-5 levels in splenic lymphocytes. We next examined the influence of IPD-1151T on co-stimulatory molecule expression on splenic lymphocytes. IPD-1151T caused suppression of CD40 and CD86 expression; however, the treatments did not affect CD80 expression.
PMCID: PMC1781737  PMID: 11817674
7.  Suppressive activity of a macrolide antibiotic, roxithromycin on co-stimulatory molecule expression on mouse splenocytes in vivo. 
Mediators of Inflammation  2000;9(1):39-43.
The influence of roxithromycin (RXM) on the expression of co-stimulatory molecules, CD40, CD80 and CD86, was examined in vivo. When BALB/c mice were immunized intraperitoneally with two doses of dinitrophenylated ovalbumin (DNP-OVA) at 1 week intervals, intraperitoneal administration of RXM at 250 microg/kg once a day for 14 days strongly suppressed IgE contents in sera obtained from mice 22 days after the first immunization. In addition, RXM treatment of mice suppressed endogenous IL-4 contents in aqueous spleen extracts, which were enhanced by DNP-OVA immunization. We next examined the influence of RXM on co-stimulatory molecule expression on splenic lymphocytes. RXM treatment of the immunized mice caused suppression of CD40 expression, but this treatment did not affect CD80 and CD86 expression.
PMCID: PMC1781739  PMID: 10877454
8.  The extracellular signal-regulated kinase pathway phosphorylates AML1, an acute myeloid leukemia gene product, and potentially regulates its transactivation ability. 
Molecular and Cellular Biology  1996;16(7):3967-3979.
AML1 (also called PEBP2alphaB, CBFA2, or CBFalpha2) is one of the most frequently disrupted genes in chromosome abnormalities seen in human leukemias. It has been reported that AML1 plays several pivotal roles in myeloid hematopoietic differentiation and other biological phenomena, probably through the transcriptional regulation of various relevant genes. Here, we investigated the mechanism of regulation of AML1 functions through signal transduction pathways. The results showed that AML1 is phosphorylated in vivo on two serine residues within the proline-, serine-, and threonine-rich region, with dependence on the activation of extracellular signal-regulated kinase (ERK) and with interleukin-3 stimulation in a hematopoietic cell line. These in vivo phosphorylation sites of AML1 were phosphorylated directly in vitro by ERK. Although differences between wild-type AML1 and phosphorylation site mutants in DNA-binding affinity were not observed, we have shown that ERK-dependent phosphorylation potentiates the transactivation ability of AML1. Furthermore the phosphorylation site mutations reduced the transforming capacity of AML1 in fibroblast cells. These data indicate that AML1 functions are potentially regulated by ERK, which is activated by cytokine and growth factor stimuli. This study provides some important clues for clarifying unidentified facets of the regulatory mechanism of AML1 function.
PMCID: PMC231393  PMID: 8668214
9.  Dual functions of the AML1/Evi-1 chimeric protein in the mechanism of leukemogenesis in t(3;21) leukemias. 
Molecular and Cellular Biology  1995;15(5):2383-2392.
The chromosomal translocation t(3;21)(q26;q22), which is found in blastic crisis in chronic myelogenous leukemias and myelodysplastic syndrome-derived leukemias, produces AML1/Evi-1 chimeric transcription factor and is thought to play important roles in acute leukemic transformation of hemopoietic stem cells. We report here the functional analyses of AML1/Evi-1. It was revealed that AML1/Evi-1 itself does not alter the transactivation level through mouse polyomavirus enhancer-binding protein 2 (PEBP2; PEA2) sites (binding site of AML1) but dominantly suppresses the transactivation by intact AML1, which is assumed to be a stimulator of myeloid cell differentiation. DNA-binding competition is a putative mechanism of such dominant negative effects of AML1/Evi-1 because it binds to PEBP2 sites with higher affinity than AML1 does. Furthermore, AML1/Evi-1 stimulated c-fos promoter transactivation and increased AP-1 activity, as Evi-1 (which is not normally expressed in hemopoietic cells) did. Experiments using deletion mutants of AML1/Evi-1 showed that these two functions are mutually independent because the dominant negative effects on intact AML1 and the stimulation of AP-1 activity are dependent on the runt domain (DNA-binding domain of AML1) and the zinc finger domain near the C terminus, respectively. Furthermore, we showed that AML1/Evi-1 blocks granulocytic differentiation, otherwise induced by granulocyte colony-stimulating factor, of 32Dcl3 myeloid cells. It was also suggested that both AML1-derived and Evi-1-derived portions of the fusion protein play crucial roles in this differentiation block. We conclude that the leukemic cell transformation in t(3;21) leukemias is probably caused by these dual functions of AML1/Evi-1 chimeric protein.
PMCID: PMC230467  PMID: 7739522
10.  Enhanced production of rat interleukin-8 by in vitro and in vivo infections with influenza A NWS virus. 
Journal of Virology  1993;67(11):6811-6814.
We investigated the interleukin-8 (IL-8)-producing activity of influenza A NWS virus in cultured rat kidney NRK-52E cells and a rat influenza model. The production of rat IL-8 increased significantly in the virus-infected cells but not in UV-inactivated virus- or split-product-treated cells. The increase in IL-8 production could be detected in the bronchoalveolar lavage of infected rats. These data suggest that infectious virus has the potential to accelerate the production of IL-8 in cultured cells and in vivo in airway-lining cells.
PMCID: PMC238123  PMID: 8411383
11.  Antibody-mediated growth of influenza A NWS virus in macrophagelike cell line P388D1. 
Journal of Virology  1988;62(1):20-26.
We investigated the internalization and growth of influenza A NWS virus in macrophagelike P388D1 cells. Flow cytometric analysis using fluorescein isothiocyanate-labeled virus showed that the attachment of normal rabbit serum-exposed virus (NS-V) to neuraminidase (NA)-treated cells was noticeably limited compared with that to untreated cells. However, rabbit antiserum-exposed virus (AS-V) could attach equally well to both cells. Virus coated with Fab prepared from antiviral immunoglobulin G could not attach. These data suggest that the NWS virus can infect P388D1 cells in one of two ways, via viral or via Fc receptors, depending on the presence of antibodies. The NS-V could grow in the untreated cells, but not in the NA-treated cells. The highest growth of AS-V in the NA-treated cells was observed at an antibody concentration showing 50% plaque reduction titer. Growth was exponentially decreased toward the lower and higher dilutions of antibodies. By using three different immunoglobulin G subclasses of monoclonal antibodies against hemagglutinin, it was demonstrated that both Fc receptors I and II could take part in this phenomenon. The presence of 20 mM NH4Cl inhibited the growth of both AS-V and NS-V, suggesting that the intracellular pathways after internalization via Fc or viral receptors are similar. These data indicate that the concentration of antibodies has a critical role on the antibody-mediated growth of influenza virus in macrophages.
PMCID: PMC250496  PMID: 3334744
12.  Eating vegetables before carbohydrates improves postprandial glucose excursions 
Diabetic Medicine  2013;30(3):370-372.
doi:10.1111/dme.12073
PMCID: PMC3674531  PMID: 23167256

Results 1-12 (12)