Tetsuji Naka

Publications (77)385.94 Total impact

• Source

  Available from: Tomoshige Matsumoto

  Dataset: Structure and function of a new STAT-induced STAT inhibitor

  Tetsuji Naka, Masashi Narazaki, Moritoshi Hirata, Tomoshige Matsumoto, Seijiro Minamoto, Atsufumi Aono, Norihiro Nishimoto, Tadahiro Kajita, Tetsuya Taga, Kazuyuki Yoshizaki, Shizuo Akira, Tadamitsu Kishimoto
• Article: Lectin-based Immunoassay for Aberrant IgG Glycosylation as the Biomarker for Crohn's Disease.

  Shinichiro Shinzaki, Eri Kuroki, Hideki Iijima, Norika Tatsunaka, Mayuko Ishii, Hironobu Fujii, Yoshihiro Kamada, Taku Kobayashi, Narihiro Shibukawa, Takahiro Inoue, Masahiko Tsujii, Shunsaku Takeishi, Tsunekazu Mizushima, Atsushi Ogata, Tetsuji Naka, Scott E Plevy, Tetsuo Takehara, Eiji Miyoshi
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  ABSTRACT: BACKGROUND:: Easily measured and clinically useful biomarkers for inflammatory bowel disease (IBD) are required to advance patient care. We previously reported that the agalactosyl fraction among fucosylated IgG oligosaccharides is increased in IBD, especially Crohn's disease (CD). The present study aimed to establish a simple detection system for aberrant glycosylated IgG based on lectin-oligosaccharide interactions. METHODS:: Lectins with higher affinity to serum IgG from IBD patients than healthy volunteers (HV) were screened by lectin microarray. Binding of selected lectins to agalactosyl IgG was definitively confirmed using step-by-step glycosidase treatment. Using the selected lectins, a lectin-enzyme-linked immunosorbent assay system was established and its clinical utility was investigated in a total of 410 (249 Japanese and 161 American) IBD patients, disease controls, and HVs. RESULTS:: Agaricus bisporus Agglutinin (ABA) and Griffonia simplicifolia Lectin-II (GSL-II) had higher affinity for serum agalactosyl IgG from IBD patients, especially those with CD, compared to HV. Agalactosyl IgG levels measured by a lectin-enzyme immunoassay (EIA) with ABA or GSL-II were significantly increased in CD compared with HV and disease controls. Agalactosyl IgG levels significantly correlated with disease activity, showed higher predictability of therapeutic outcomes for CD than C-reactive protein levels, and exhibited higher specificity for diagnosing IBD in combination with anti-Saccharomyces cerevisiae antibody (ASCA). Validation analysis showed that agalactosyl IgG levels were significantly increased in Japanese and American CD patients. CONCLUSIONS:: A lectin-EIA for agalactosyl IgG is a novel biomarker for IBD, especially in patients with CD.
  Inflammatory Bowel Diseases 12/2012; · 4.86 Impact Factor
• Article: Plasma membrane proteomics identifies bone marrow stromal antigen 2 as a potential therapeutic target in endometrial cancer.

  Takuhei Yokoyama, Takayuki Enomoto, Satoshi Serada, Akiko Morimoto, Shinya Matsuzaki, Yutaka Ueda, Kiyoshi Yoshino, Masami Fujita, Satoru Kyo, Kota Iwahori, Minoru Fujimoto, Tadashi Kimura, Tetsuji Naka
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  ABSTRACT: This report utilizes a novel proteomic method for discovering potential therapeutic targets in endometrial cancer. We used a biotinylation-based approach for cell-surface protein enrichment combined with isobaric tags for relative and absolute quantitation (iTRAQ) technology using nano liquid chromatography-tandem mass spectrometry analysis to identify specifically overexpressed proteins in endometrial cancer cells compared with normal endometrial cells. We identified a total of 272 proteins, including 11 plasma membrane proteins, whose expression increased more than twofold in at least four of seven endometrial cancer cell lines compared with a normal endometrial cell line. Overexpression of bone marrow stromal antigen 2 (BST2) was detected and the observation was supported by immunohistochemical analysis using clinical samples. The expression of BST2 was more characteristic of 118 endometrial cancer tissues compared with 59 normal endometrial tissues (p < 0.0001). The therapeutic effect of an anti-BST2 antibody was studied both in vitro and in vivo. An anti-BST2 monoclonal antibody showed in vitro cytotoxicity in BST2-positive endometrial cancer cells via antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity. In an in vivo xenograft model, anti-BST2 antibody treatment significantly inhibited tumor growth of BST2-positive endometrial cancer cells in an NK cell-dependent manner. The anti-BST2 antibody had a potent antitumor effect against endometrial cancer both in vitro and in vivo, indicating a strong potential for clinical use of anti-BST2 antibody for endometrial cancer treatment. The combination of biotinylation-based enrichment of cell-surface proteins and iTRAQ analysis should be a useful screening method for future discovery of potential therapeutic targets.
  International Journal of Cancer 06/2012; · 5.44 Impact Factor
• Article: Periostin, a matricellular protein, accelerates cutaneous wound repair by activating dermal fibroblasts.

  Kanako Ontsuka, Yorihisa Kotobuki, Hiroshi Shiraishi, Satoshi Serada, Shoichiro Ohta, Atsushi Tanemura, Lingli Yang, Minoru Fujimoto, Kazuhiko Arima, Shoichi Suzuki, Hiroyuki Murota, Shuji Toda, Akira Kudo, Simon J Conway, Yutaka Narisawa, Ichiro Katayama, Kenji Izuhara, Tetsuji Naka
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  ABSTRACT: Cutaneous wound repair is a highly ordered and well-coordinated process involving various cell lineages and many molecular effectors. Cell-matrix interactions through integrin molecules provide key signals important for wound repair. Periostin is a matricellular protein that may provide signals important during tissue development and remodelling by interacting with several integrin molecules, via the phosphatidylinositol 3-kinase/Akt and MAP kinase pathways. In this study, we examined the role of periostin in the process of cutaneous wound repair using periostin-deficient mice and by analysing the effects of periostin on dermal fibroblasts. We first determined the expression profile and localization of periostin in a well-characterized wound repair model mice. Periostin was robustly deposited in the granulation tissues beneath the extended epidermal wound edges and at the dermal-epidermal junctions in wounded mice. Moreover, periostin-deficient mice exhibited delayed in vivo wound repair, which could be improved by direct administration of exogenous periostin. In vitro analyses revealed that loss of periostin impaired proliferation and migration of dermal fibroblasts, but exogenous supplementation or enforced periostin expression enhanced their proliferation. Combined, these results demonstrate that periostin accelerates the process of cutaneous wound repair by activating fibroblasts.
  Experimental Dermatology 05/2012; 21(5):331-6. · 3.54 Impact Factor
• Article: SOCS-1 gene delivery cooperates with cisplatin plus pemetrexed to exhibit preclinical antitumor activity against malignant pleural mesothelioma.

  Kota Iwahori, Satoshi Serada, Minoru Fujimoto, Barry Ripley, Shintaro Nomura, Hiroyuki Mizuguchi, Kazuki Shimada, Tsuyoshi Takahashi, Ichiro Kawase, Tadamitsu Kishimoto, Tetsuji Naka
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  ABSTRACT: Malignant pleural mesothelioma (MPM) is an aggressive tumor with poor prognosis for which an effective therapy remains to be established. This study investigated the therapeutic potential of gene delivery using suppressor of cytokine signaling 1 (SOCS-1), an endogenous inhibitor of intracellular signaling pathways, for the treatment of MPM. We infected MPM cells (MESO-4, H28 and H226) with adenovirus-expressing SOCS-1 vector to examine the effect of SOCS-1 overexpression on MPM cells. We evaluated the antitumor effect of SOCS-1 gene delivery combined with cisplatin plus pemetrexed by cell proliferation, apoptosis and invasion assay. We also investigated the regulation of NF-κB and STAT3 signaling related to apoptotic pathways. Furthermore, we evaluated the inhibition of tumor growth by SOCS-1 gene delivery combined with cisplatin plus pemetrexed in vivo. SOCS-1 gene delivery cooperated with cisplatin plus pemetrexed to inhibit cell proliferation, invasiveness and induction of apoptosis in MPM cells. SOCS-1 regulated NF-κB and STAT3 signaling to induce apoptosis in MESO-4 and H226 cells. Furthermore, SOCS-1 gene delivery cooperated with cisplatin plus pemetrexed to regulate NF-κB signaling and significantly inhibit tumor growth of MPM in vivo. These results suggest that SOCS-1 gene delivery has a potent antitumor effect against MPM and a potential for clinical use in combination with cisplatin plus pemetrexed.
  International Journal of Cancer 04/2012; · 5.44 Impact Factor
• Article: Serum HE4 as a diagnostic and prognostic marker for lung cancer.

  Kota Iwahori, Hidekazu Suzuki, Yoshiro Kishi, Yoshihiro Fujii, Rie Uehara, Norio Okamoto, Masashi Kobayashi, Tomonori Hirashima, Ichiro Kawase, Tetsuji Naka
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  ABSTRACT: We evaluated the diagnostic and prognostic efficacy of human epididymis protein 4 (HE4) for lung cancer patients by using our novel enzyme-linked immunosorbent assay (ELISA) system. We measured serum HE4 levels of cancer patients including 49 lung cancer and 18 ovarian cancer patients. Furthermore, we evaluated the relationship between serum HE4 levels and overall survival after chemotherapy of 24 lung cancer patients. Serum HE4 levels were significantly higher for non-small, small cell lung cancer and ovarian cancer patients than for healthy controls. The area under the receiver operating characteristic curve (AUC) was calculated for differentiation of lung cancer patients and healthy controls. AUC for serum HE4 was 0.988 for differentiating lung cancer patients from healthy controls, with a cutoff value of 6.56 ng/ml (sensitivity = 89.8%, specificity = 100%). Serum HE4 levels were elevated in 36/40 (90.0%) non-small cell lung cancer patients, 8/9 (88.9%) small cell lung cancer patients and 8/18 (44.4%) ovarian cancer patients. High levels of serum HE4 (>15 ng/ml) after chemotherapy were significantly correlated with worse overall survival after the treatment. These findings suggest that serum HE4 is a potential diagnostic and prognostic marker for lung cancer patients.
  Tumor Biology 02/2012; 33(4):1141-9. · 1.94 Impact Factor
• Article: Serum leucine-rich alpha-2 glycoprotein is a disease activity biomarker in ulcerative colitis.

  Satoshi Serada, Minoru Fujimoto, Fumitaka Terabe, Hideki Iijima, Shinichiro Shinzaki, Shinya Matsuzaki, Tomoharu Ohkawara, Riichiro Nezu, Sachiko Nakajima, Taku Kobayashi, Scott Eric Plevy, Tetsuo Takehara, Tetsuji Naka
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  ABSTRACT: Reliable biomarkers for monitoring disease activity have not been clinically established in ulcerative colitis (UC). This study aimed to investigate whether levels of serum leucine-rich alpha-2 glycoprotein (LRG), identified recently as a potential disease activity marker in Crohn's disease and rheumatoid arthritis, correlate with disease activity in UC. Serum LRG concentrations were determined by enzyme-linked immunosorbent assay (ELISA) in patients with UC and healthy controls (HC) and were evaluated for correlation with disease activity. Expression of LRG in inflamed colonic tissues from patients with UC was analyzed by western blotting and immunohistochemistry. Interleukin (IL)-6-independent induction of LRG was investigated using IL-6-deficient mice by lipopolysaccharide (LPS)-mediated acute inflammation and dextran sodium sulfate (DSS)-induced colitis. Serum LRG concentrations were significantly elevated in active UC patients compared with patients in remission (P < 0.0001) and HC (P < 0.0001) and were correlated with disease activity in UC better than C-reactive protein (CRP). Expression of LRG was increased in inflamed colonic tissues in UC. Tumor necrosis factor alpha (TNF-α), IL-6, and IL-22, serum levels of which were elevated in patients with active UC, could induce LRG expression in COLO205 cells. Serum LRG levels were increased in IL-6-deficient mice with LPS-mediated acute inflammation and DSS-induced colitis. Serum LRG concentrations correlate well with disease activity in UC. LRG induction is robust in inflamed colons and is likely to involve an IL-6-independent pathway. Serum LRG is thus a novel serum biomarker for monitoring disease activity in UC and is a promising surrogate for CRP. (Inflamm Bowel Dis 2012;).
  Inflammatory Bowel Diseases 02/2012; 18(11):2169-79. · 4.86 Impact Factor
• Source

  Available from: Takayuki Enomoto

  Article: Therapeutic strategies in epithelial ovarian cancer.

  Ayako Kim, Yutaka Ueda, Tetsuji Naka, Takayuki Enomoto
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  ABSTRACT: Ovarian cancer is the most lethal gynecologic malignancy. It appears that the vast majority of what seem to be primary epithelial ovarian and primary peritoneal carcinomas is, in fact, secondary from the fimbria, the most distal part of the fallopian tube. Treatment of epithelial ovarian cancer is based on the combination of cytoreductive surgery and combination chemotherapy using taxane and platinum. Although clear cell type is categorized in indolent type, it is known to show relatively strong resistance to carboplatin and paclitaxel regimen and thus poor prognosis compared to serous adenocarcinoma, especially in advanced stages. Irinotecan plus cisplatin therapy may effective for the clear cell adenocarcinoma. The larger expectation for improved prognosis in ovarian carcinoma is related to the use of the new biological agents. One of the most investigated and promising molecular targeted drugs in ovarian cancer is bevacizumab, a monoclonal antibody directed against VEGF. PARP inhibitor is another one. A few recent studies demonstrated positive results of bevacizumab on progression-free survival in ovarian cancer patients, however, investigation of molecular targeting drugs in patients with ovarian cancer are still underway.
  Journal of Experimental & Clinical Cancer Research 02/2012; 31:14. · 2.15 Impact Factor
• Article: Periostin facilitates skin sclerosis via PI3K/Akt dependent mechanism in a mouse model of scleroderma.

  Lingli Yang, Satoshi Serada, Minoru Fujimoto, Mika Terao, Yorihisa Kotobuki, Shun Kitaba, Saki Matsui, Akira Kudo, Tetsuji Naka, Hiroyuki Murota, Ichiro Katayama
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  ABSTRACT: Periostin, a novel matricellular protein, is recently reported to play a crucial role in tissue remodeling and is highly expressed under fibrotic conditions. This study was undertaken to assess the role of periostin in scleroderma. Using skin from patients and healthy donors, the expression of periostin was assessed by immunohistochemistry and immunoblotting analyses. Furthermore, we investigated periostin(-/-) (PN(-/-)) and wild-type (WT) mice to elucidate the role of periostin in scleroderma. To induce murine cutaneous sclerosis, mice were subcutaneously injected with bleomycin, while untreated control groups were injected with phosphate-buffered saline. Bleomycin-induced fibrotic changes were compared in PN(-/-) and WT mice by histological analysis as well as by measurements of profibrotic cytokine and extracellular matrix protein expression levels in vivo and in vitro. To determine the downstream pathway involved in periostin signaling, receptor neutralizing antibody and signal transduction inhibitors were used in vitro. Elevated expression of periostin was observed in the lesional skin of patients with scleroderma compared with healthy donors. Although WT mice showed marked cutaneous sclerosis with increased expression of periostin and increased numbers of myofibroblasts after bleomycin treatment, PN(-/-) mice showed resistance to these changes. In vitro, dermal fibroblasts from PN(-/-) mice showed reduced transcript expression of alpha smooth actin and procollagen type-I alpha 1 (Col1α1) induced by transforming growth factor beta 1 (TGFβ1). Furthermore, recombinant mouse periostin directly induced Col1α1 expression in vitro, and this effect was inhibited by blocking the αv integrin-mediated PI3K/Akt signaling either with anti-αv functional blocking antibody or with the PI3K/Akt kinase inhibitor LY294002. Periostin plays an essential role in the pathogenesis of Bleomycin-induced scleroderma in mice. Periostin may represent a potential therapeutic target for human scleroderma.
  PLoS ONE 01/2012; 7(7):e41994. · 4.09 Impact Factor
• Article: Dysregulation of melanocyte function by Th17-related cytokines: significance of Th17 cell infiltration in autoimmune vitiligo vulgaris.

  Yorihisa Kotobuki, Atsushi Tanemura, Lingli Yang, Saori Itoi, Mari Wataya-Kaneda, Hiroyuki Murota, Minoru Fujimoto, Satoshi Serada, Tetsuji Naka, Ichiro Katayama
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  ABSTRACT: The aim of this study was to determine whether CD4(+) IL-17A(+) Th17 cells infiltrate vitiligo skin and to investigate whether the proinflammatory cytokines related to Th17 cell influence melanocyte enzymatic activity and cell fate. An immunohistochemical analysis showed Th17 cell infiltration in 21 of 23 vitiligo skin samples in addition to CD8(+) cells on the reticular dermis. An in vitro analysis showed that the expression of MITF and downstream genes was downregulated in melanocytes by treatment with interleukin (IL)-17A, IL-1β, IL-6, and tumor necrosis factor (TNF)-α. Treatment with these cytokines also induced morphological shrinking in melanocytes, resulting in decreased melanin production. In terms of local cytokine network in the skin, IL-17A dramatically induced IL-1β, IL-6, and TNF-α production in skin-resident cells such as keratinocytes and fibroblasts. Our results provide evidence of the influence of a complex Th17 cell-related cytokine environment in local depigmentation in addition to CD8(+) cell-mediated melanocyte destruction in autoimmune vitiligo.
  Pigment Cell & Melanoma Research 12/2011; 25(2):219-30. · 5.06 Impact Factor
• Article: Antiproliferative effect of SOCS-1 through the suppression of STAT3 and p38 MAPK activation in gastric cancer cells.

  Yoshihito Souma, Toshirou Nishida, Satoshi Serada, Kota Iwahori, Tsuyoshi Takahashi, Minoru Fujimoto, Barry Ripley, Kiyokazu Nakajima, Yasuaki Miyazaki, Masaki Mori, Yuichiro Doki, Yoshiki Sawa, Tetsuji Naka
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  ABSTRACT: Inflammation is a crucial driving force in the development of gastric cancers (GCs). Accordingly, persistent activation of STAT3, a transcription factor pivotal in regulating both inflammation and oncogenesis, is often detected in GC, although its mechanism remains elusive. Suppressor of cytokine signaling-1 (SOCS-1) is a negative regulator of proinflammatory cytokine signaling and SOCS-1 gene methylation is frequently detected in various cancers including GC. However, the significance of SOCS-1 methylation in GC cells remains unexplored. Our study is undertaken to evaluate the role of SOCS-1 in GC cell proliferation and its effect on signaling pathways in GC cells. Among five GC cell lines, SOCS-1 gene was methylated in all cell lines and constitutive STAT3 phosphorylation with elevated endogenous IL-6 production was detected in two cell lines (NUGC-3 and AGS). Unexpectedly, anti-IL-6R antibody inhibited neither cell proliferation nor STAT3 phosphorylation in NUGC-3 and AGS. In contrast, enforced SOCS-1 expression by adenoviral vector (AdSOCS-1) markedly suppressed STAT3 phosphorylation and proliferation of NUGC-3 and AGS cells in vitro. Interestingly, the antiproliferative effect of SOCS-1 was attributable not only to the inhibition of STAT3 but also to that of p38 MAPK activity, and chemical inhibitors of JAK/STAT and p38 MAPK signaling effectively suppressed proliferation of these GC cells. Furthermore, treatment with AdSOCS-1 in vivo significantly suppressed GC proliferation in a xenograft model. These results suggest that SOCS-1 gene methylation is a critical step in the development of GC, and enforced expression of SOCS-1 may represent a novel therapeutic approach for the treatment of GC.
  International Journal of Cancer 11/2011; 131(6):1287-96. · 5.44 Impact Factor
• Source

  Available from: InTech

  Chapter: Application of Novel Quantitative Proteomic Technologies to Identify New Serological Biomarkers in Autoimmune Diseases

  Soyoung Lee, Satoshi Serada, Minoru Fujimoto, Tetsuji Naka
  11/2011; , ISBN: 978-953-307-653-9
• Article: Blockade of interleukin-6 receptor alleviates disease in mouse model of scleroderma.

  Shun Kitaba, Hiroyuki Murota, Mika Terao, Hiroaki Azukizawa, Fumitaka Terabe, Yoshihito Shima, Minoru Fujimoto, Toshio Tanaka, Tetsuji Naka, Tadamitsu Kishimoto, Ichiro Katayama
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  ABSTRACT: Activation of fibroblasts by interleukin-6 (IL-6) is implicated in the pathogenesis of scleroderma, suggesting that the inhibition of fibroblast activation may be a promising scleroderma treatment. In this study, we used an IL-6 blocking antibody (Ab) and Il-6 knockout (Il-6KO) mice to examine the role of IL-6 in the bleomycin (BLM)-induced mouse model of scleroderma. BLM was administered to C57BL/6 and Il-6KO mice to induce dermal sclerosis. BLM-treated and control phosphate-buffered saline-treated mice were treated with anti-mouse IL-6 receptor monoclonal Ab (MR16-1). Disease severity was evaluated by measuring dermal thickness and skin hardness, by counting the numbers of α-smooth muscle actin-positive cells and mast cells, and by examining the cutaneous draining lymph nodes. C57BL/6 mice with BLM induced scleroderma had elevated serum IL-6 levels and more severe dermal sclerosis than Il-6KO mice. Weekly administration of MR16-1, but not control Ab, prevented and improved dermal sclerosis, and also attenuated swelling of the draining lymph nodes. MR16-1 suppressed α-smooth muscle actin induction in IL-6-stimulated Il-6KO fibroblasts. Our results indicate that IL-6 contributes to BLM induced dermal sclerosis and that IL-6 receptor-specific monoclonal Ab may improve the symptoms of scleroderma by suppressing fibroblast activation.
  American Journal Of Pathology 11/2011; 180(1):165-76. · 4.89 Impact Factor
• Source

  Available from: zen-bio.com

  Article: Overexpression of SOCS3 exhibits preclinical antitumor activity against malignant pleural mesothelioma.

  Kota Iwahori, Satoshi Serada, Minoru Fujimoto, Shintaro Nomura, Tadashi Osaki, Chun Man Lee, Hiroyuki Mizuguchi, Tsuyoshi Takahashi, Barry Ripley, Meinoshin Okumura, Ichiro Kawase, Tadamitsu Kishimoto, Tetsuji Naka
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  ABSTRACT: Malignant pleural mesothelioma (MPM) is an aggressive tumor with poor prognosis for which an effective therapy remains to be established. Our study investigated the therapeutic potential of the suppressor of cytokine signaling 3 (SOCS3), an endogenous inhibitor of intracellular signaling pathways, for treatment of MPM. We infected MPM cells (H226, EHMES-1, MESO-1 and MESO-4) with an adenovirus-expressing SOCS3 (AdSOCS3) to examine the effect of SOCS3 overexpression on MPM cells. SOCS3 overexpression reduced MPM proliferation and induced apoptosis and partial G0/G1 arrest. SOCS3 also inhibited the proliferation of MPM cells via multiple signaling pathways including Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3), extracellular signal-regulated kinase (ERK), focal adhesion kinase (FAK) and p53 pathways. Notably, AdSOCS3 treatment inhibited tumor growth in an MPM pleural xenograft model. These findings demonstrate that overexpression of SOCS3 has a potent antitumor effect against MPM both in vitro and in vivo and indicate the potential for clinical use of SOCS3 for MPM treatment.
  International Journal of Cancer 08/2011; 129(4):1005-17. · 5.44 Impact Factor
• Article: IL-6-mediated Th17 differentiation through RORγt is essential for the initiation of experimental autoimmune myocarditis.

  Tomomi Yamashita, Tomohiko Iwakura, Kazuki Matsui, Haruyo Kawaguchi, Masanori Obana, Akiko Hayama, Makiko Maeda, Yasukatsu Izumi, Issei Komuro, Yoshiyuki Ohsugi, Minoru Fujimoto, Tetsuji Naka, Tadamitsu Kishimoto, Hiroyuki Nakayama, Yasushi Fujio
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  ABSTRACT: Interleukin (IL)-17-producing helper T (Th17) cells have been proposed to participate in the pathogenesis of chronic inflammation, such as autoimmune myocarditis. IL-6 gene ablation confers the resistance to experimental autoimmune myocarditis (EAM). In this study, we have addressed the pathological roles of IL-6 in the regulation of Th17 cells in EAM. To induce EAM, mice were immunized twice with α-myosin heavy chain peptide. Three weeks after the first injection, the cardiac expression of the Th17-specific transcription factor, retinoic acid receptor-related orphan nuclear receptor (ROR γt), was up-regulated. Consistently, Th17 cells were recruited into EAM hearts, as analysed by flow cytometry. Using the mice with enhanced green fluorescence protein (eGFP) gene knocked-in at RORγt locus (RORγt-eGFP mice), we observed Th17 cell infiltration into inflamed lesions. Pre-treatment with IL-6 receptor (IL-6R)-blocking antibody (anti-IL-6R Ab) inhibited EAM induction in terms of disease severity score (3.5 ± 0.8; IgG vs. 0.5 ± 0.8; anti-IL-6R Ab, n = 6, P< 0.01) and suppressed the myocardial expression of IL-17 and RORγt. In contrast, the administration of anti-IL-6R Ab 7 days after the first immunization failed to show the inhibitory effects, suggesting that IL-6 plays important roles in EAM initiation. Finally, by generating RORγt-eGFP homozygous mice, we revealed that RORγt gene ablation conferred the resistance to EAM induction. IL-6-mediated induction of Th17 cells is critical for the onset of EAM, but not for its progression. IL-6/Th17 signalling could be a promising therapeutic target for the prevention of myocardial inflammation.
  Cardiovascular research 05/2011; 91(4):640-8. · 5.80 Impact Factor
• Article: Blockade of interleukin-6 signaling suppresses not only th17 but also interphotoreceptor retinoid binding protein-specific Th1 by promoting regulatory T cells in experimental autoimmune uveoretinitis.

  Hiroshi Haruta, Nobuyuki Ohguro, Minoru Fujimoto, Satoshi Hohki, Fumitaka Terabe, Satoshi Serada, Shintaro Nomura, Kohji Nishida, Tadamitsu Kishimoto, Tetsuji Naka
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  ABSTRACT: PURPOSE. Both Th17 and Th1 cells contribute to experimental autoimmune uveoretinitis (EAU). Interleukin-6 (IL-6) blockade inhibits Th17 differentiation in EAU and potently suppresses ocular inflammation, although its effect on Th1 cells is unknown. To clarify the mechanism of IL-6 blockade, the authors investigated T helper cells with particular focus on Th1 and regulatory T cells (Treg) in EAU of IL-6 gene knockout (KO) mice. METHODS. EAU was induced in wild-type (WT) mice and in mice lacking IL-6 (IL-6KO), IL-17 (IL-17KO), and IFN-γ (GKO) on a C57BL/6 background. Clinical scores of EAU, cytokine levels in supernatants from ocular tissue homogenates, and T helper cell differentiation in lymph nodes in each mouse were examined. To study the roles of Treg cells, EAU was induced in IL-6KO mice treated with anti-CD25 monoclonal antibody (mAb) to deplete Treg cells in vivo. RESULTS. Inflammation was comparable between WT, IL-17KO, and GKO mice but was absent in IL-6KO mice. Th17 and interphotoreceptor retinoid binding protein (IRBP)-specific Th1 cells were increased in GKO and IL-17KO mice, respectively, whereas both populations were reduced in IL-6KO mice. Th1-dominant EAU in IL-17KO mice was suppressed by anti-IL-6R mAb treatment. Treg cell depletion in vivo induced EAU in IL-6KO mice. CONCLUSIONS. After the induction of EAU, IL-6 deficiency resulted in the inhibition of the IRBP-specific Th1 response and enhanced the generation of IRBP-specific Treg cells. Furthermore, Treg was needed to inhibit Th1 responses and ocular inflammation in IL-6KO mice. Protective effects of IL-6 signaling blockade in EAU involve not only Th17 cell inhibition but also IRBP-specific Treg cell promotion.
  Investigative ophthalmology & visual science 02/2011; 52(6):3264-71. · 3.43 Impact Factor
• Article: Comparative analysis of the effects of anti-IL-6 receptor mAb and anti-TNF mAb treatment on CD4+ T-cell responses in murine colitis.

  Fumitaka Terabe, Minoru Fujimoto, Satoshi Serada, Shinichiro Shinzaki, Hideki Iijima, Masahiko Tsujii, Norio Hayashi, Shintaro Nomura, Hirohisa Kawahata, Myoung Ho Jang, Masayuki Miyasaka, Masahiko Mihara, Yoshiyuki Ohsugi, Tadamitsu Kishimoto, Tetsuji Naka
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  ABSTRACT: The efficacy of anti-tumor necrosis factor monoclonal antibody (anti-TNF mAb) for Crohn's disease (CD) is well established, and anti-interleukin-6 receptor (anti-IL-6R) mAb has also been reported to be effective in CD. It is, however, unclear if the efficacy and mechanisms of both agents are different in CD therapy. Using an adoptive transfer colitis model, we compared the efficacy of anti-IL-6R mAb, anti-TNF mAb, and TNF receptor-Fc fusion protein (TNFR-Fc), and their modes of action on CD4+ T cells. We also investigated the role of Th1 and Th17 cells in colitis using the same model. The histological scores for the anti-IL-6R mAb and anti-TNF mAb groups but not for TNFR-Fc group were much lower than that for the control group, and the score was the lowest for the anti-IL-6R mAb group. The frequency of proliferating CD4+ T cells was reduced in anti-IL-6R mAb and anti-TNF mAb groups, but not in the TNFR-Fc group, whereas the frequency of apoptotic CD4+ T cells was similar in all groups. Anti-IL-6R mAb suppressed the induction of Th17 cells and increased the frequency of lamina propria regulatory T cells, whereas anti-TNF mAb exerted no influence on CD4+ T-cell differentiation. A deficiency in interferon-γ and/or IL-17 in CD4+ T cells reduced the severity of colitis. Our findings suggest that suppression of the proliferation of pathogenic CD4+ T cells is the major mode of action of biological agents for colitis therapy. Anti-IL-6R mAb might have benefits in CD patients with Th17 dominance and impaired Treg frequency.
  Inflammatory Bowel Diseases 02/2011; 17(2):491-502. · 4.86 Impact Factor
• Article: Reprint of: Nanoparticles for ex vivo siRNA delivery to dendritic cells for cancer vaccines: Programmed endosomal escape and dissociation.

  Hidetaka Akita, Kentaro Kogure, Rumiko Moriguchi, Yoshio Nakamura, Tomoko Higashi, Takashi Nakamura, Satoshi Serada, Minoru Fujimoto, Tetsuji Naka, Shiroh Futaki, Hideyoshi Harashima
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  ABSTRACT: We previously developed octaarginine (R8)-modified lipid envelope-type nanoparticles for siRNA delivery (R8-MEND). Herein, we report on their ex vivo siRNA delivery to primary mouse bone marrow-derived dendritic cells (BMDCs) for potential use as a cancer vaccine. Quantitative imaging analysis of the intracellular trafficking of siRNA revealed that the dissociation process, as well as the rate of endosomal escape limits the siRNA efficiency of the prototype R8-MEND, prepared by the hydration method (R8-MEND(hydo)). Successful endosomal escape was achieved by using a pH-dependent fusogenic peptide (GALA) modified on a lipid mixture that was optimized for endosomal fusion. Furthermore, a modified protocol for the preparation of nanoparticles, mixing the siRNA/STR-R8 complex and small unilamellar vesicles (R8/GALA-MEND(SUV)), results in a more homogenous, smaller particle size, and results in a more efficient intracellular dissociation. Gene knockdown of the suppressor of cytokine signaling 1 (SOCS1), a negative-feedback regulator of the immune response in BMDCs resulted in an enhanced phosphorylation of STAT1, and the production of proinflammatory cytokines. Moreover, SOCS1-silenced BMDCs were more potent in suppressing tumor growth. Collectively, these results show that siRNA loaded in R8/GALA-MEND(SUV) efficiently suppresses endogenous gene expression and consequently enhances dendritic cell-based vaccine potency in vivo.
  Journal of Controlled Release 01/2011; 149(1):58-64. · 5.73 Impact Factor
• Article: Therapeutic effect of PEGylated TNFR1-selective antagonistic mutant TNF in experimental autoimmune encephalomyelitis mice.

  Tetsuya Nomura, Yasuhiro Abe, Haruhiko Kamada, Hiroko Shibata, Hiroyuki Kayamuro, Masaki Inoue, Tomoyuki Kawara, Shuhei Arita, Takeshi Furuya, Takuya Yamashita, [......], Tomoaki Yoshikawa, Yasuo Yoshioka, Yohei Mukai, Shinsaku Nakagawa, Madoka Taniai, Tsunetaka Ohta, Satoshi Serada, Tetsuji Naka, Shin-ichi Tsunoda, Yasuo Tsutsumi
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  ABSTRACT: Multiple sclerosis (MS) is an inflammatory demyelinating disease, the pathogenesis of which is related to elevated serum levels of tumor necrosis factor-α (TNF). Although anti-TNF therapy has been tested as a potential treatment for MS, no remission of symptoms was observed. Recent reports indicated that the TNFR1 signal was responsible for the pathogenesis of murine experimental autoimmune encephalomyelitis (EAE), while the TNFR2 signal was responsible for recovery of the pathogenesis of EAE. Therefore, selective blocking of TNFR1 appears to be a promising strategy for the treatment of MS. In this regard, we previously succeeded in developing a novel TNFR1-selective antagonistic TNF mutant (R1antTNF) by using phage display technology. Here, we have examined the therapeutic potential of R1antTNF using EAE mice. Treatment with PEGylated R1antTNF (PEG-R1antTNF) significantly improved the clinical score and cerebral demyelination at the onset of EAE. Considerable suppression of Th1 and Th17-type response was also observed in spleen and lymph node cells of mice given PEG-R1antTNF. Moreover, the administration of PEG-R1antTNF suppressed the infiltration of inflammatory cells containing Th1 and Th17 cells into the spinal cord. These results suggest that selective blocking of TNFR1 by PEG-R1antTNF could be an effective therapeutic strategy against MS.
  Journal of Controlled Release 01/2011; 149(1):8-14. · 5.73 Impact Factor
• Article: The influence of excessive IL-6 production in vivo on the development and function of Foxp3+ regulatory T cells.

  Minoru Fujimoto, Mayumi Nakano, Fumitaka Terabe, Hirohisa Kawahata, Tomoharu Ohkawara, Yongmei Han, Barry Ripley, Satoshi Serada, Teppei Nishikawa, Akihiro Kimura, Shintaro Nomura, Tadamitsu Kishimoto, Tetsuji Naka
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  ABSTRACT: IL-6 is a proinflammatory cytokine and its overproduction is implicated in a variety of inflammatory disorders. Recent in vitro analyses suggest that IL-6 is a key cytokine that determines the balance between Foxp3(+) regulatory T cells (Tregs) and Th17 cells. However, it remains unclear whether excessive IL-6 production in vivo alters the development and function of Foxp3(+) Tregs. In this study, we analyzed IL-6 transgenic (Tg) mice in which serum IL-6 levels are constitutively elevated. Interestingly, in IL-6 Tg mice, whereas peripheral lymphoid organs were enlarged, and T cells exhibited activated phenotype, Tregs were not reduced but rather increased compared with wild-type mice. In addition, Tregs from Tg mice normally suppressed proliferation of naive T cells in vitro. Furthermore, Tregs cotransferred with naive CD4 T cells into SCID-IL-6 Tg mice inhibited colitis as successfully as those transferred into control SCID mice. These results indicate that overproduction of IL-6 does not inhibit development or function of Foxp3(+) Tregs in vivo. However, when naive CD4 T cells alone were transferred, Foxp3(+) Tregs retrieved from SCID-IL-6 Tg mice were reduced compared with SCID mice. Moreover, the Helios(-) subpopulation of Foxp3(+) Tregs, recently defined as extrathymic Tregs, was significantly reduced in IL-6 Tg mice compared with wild-type mice. Collectively, these results suggest that IL-6 overproduced in vivo inhibits inducible Treg generation from naive T cells, but does not affect the development and function of natural Tregs.
  The Journal of Immunology 01/2011; 186(1):32-40. · 5.79 Impact Factor