Masuo Kondoh

Osaka University, Suika, Ōsaka, Japan

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Publications (146)440.02 Total impact

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    ABSTRACT: Tight junctions (TJs) are complex biochemical structures that seal the intercellular space and prevent the free movement of solutes across epithelial cell sheets. Modulating the TJ seal is a promising option for increasing the transdermal absorption of drugs. Within TJs, the binding of the claudin (CLDN) family of tetra-transmembrane proteins through cis- and trans-interactions is an integral part of seal formation. Because epidermal TJs contain CLDN-1 and -4, a binder for these CLDNs may be a useful modulator of the permeability of the epidermal barrier. Here we investigated whether m19, which can bind to CLDN-1/-4 (also CLDN-2/-5), modulates the integrity of epidermal TJs and the permeability of cell sheets to solutes. Treatment of normal human epidermal keratinocytes (NHEKs) with the CLDNs binder reduced the integrity of TJs. A CLDN-1-specific binder (a monoclonal antibody, clone 7A5) also weakened the TJ seal in NHEKs. Although m19 attenuated the TJ barrier in human intestinal epithelial cells (Caco-2), 7A5 did not. Treatment of NHEKs with 7A5 enhanced permeation of a paracellular permeation marker. These findings indicate that CLDN-1 is a potential target for modulating the permeability of the epidermis and that our CLDN-1 binder is a promising candidate molecule for development as a dermal absorption enhancer. The American Society for Pharmacology and Experimental Therapeutics.
    Journal of Pharmacology and Experimental Therapeutics 07/2015; DOI:10.1124/jpet.115.225391 · 3.86 Impact Factor
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    ABSTRACT: Efficient vaccine delivery to mucosal tissues including mucosa-associated lymphoid tissues is essential for the development of mucosal vaccine. We previously reported that claudin-4 was highly expressed on the epithelium of nasopharynx-associated lymphoid tissue (NALT) and thus claudin-4-targeting using C-terminal fragment of Clostridium perfringens enterotoxin (C-CPE) effectively delivered fused antigen to NALT and consequently induced antigen-specific immune responses. In this study, we applied the C-CPE-based vaccine delivery system to develop a nasal pneumococcal vaccine. We fused C-CPE with pneumococcal surface protein A (PspA), an important antigen for the induction of protective immunity against Streptococcus pneumoniae infection, (PspA-C-CPE). PspA-C-CPE binds to claudin-4 and thus efficiently attaches to NALT epithelium, including antigen-sampling M cells. Nasal immunization with PspA-C-CPE induced PspA-specific IgG in the serum and bronchoalveolar lavage fluid (BALF) as well as IgA in the nasal wash and BALF. These immune responses were sufficient to protect against pneumococcal infection. These results suggest that C-CPE is an efficient vaccine delivery system for the development of nasal vaccines against pneumococcal infection.
    PLoS ONE 05/2015; 10(5):e0126352. DOI:10.1371/journal.pone.0126352 · 3.23 Impact Factor
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    ABSTRACT: Lentinula edodes mycelia solid culture extract (MSCE) contains several bioactive molecules, including some polyphenolic compounds, which exert immunomodulatory, antitumor, and hepatoprotective effects. In this study, we examined the anti-hepatitis C virus (HCV) activity of MSCE and low-molecular-weight lignin (LM-lignin), which is the active component responsible for the hepatoprotective effect of MSCE. Both MSCE and LM-lignin inhibited the entry of two HCV pseudovirus (HCVpv) types into Huh7.5.1 cells. LM-lignin inhibited HCVpv entry at a lower concentration than MSCE and inhibited the entry of HCV particles in cell culture (HCVcc). MSCE also inhibited HCV subgenome replication. LM-lignin had no effect on HCV replication, suggesting that MSCE contains additional active substances. We demonstrate here for the first time the anti-HCV effects of plant-derived LM-lignin and MSCE. The hepatoprotective effect of LM-lignin suggests that lignin derivatives, which can be produced in abundance from existing plant resources, may be effective in the treatment of HCV-related diseases. Copyright © 2015 Elsevier Inc. All rights reserved.
    Biochemical and Biophysical Research Communications 04/2015; 462(1). DOI:10.1016/j.bbrc.2015.04.104 · 2.28 Impact Factor
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    ABSTRACT: Claudins constitute a family of at least 27 proteins with four transmembrane domains, and play a pivotal role in maintaining tight-junctions seals in diverse epithelial tissues. The expression of claudin-4 often changes in intestinal tissues of inflammatory bowel disease and various human cancers. Therefore, claudin-4 is a promising target for treatment of these diseases. In our previous study, we established a reporter cell line to monitor claudin-4 expression on the basis of a functional claudin-4 promoter. Using this cell line, we have performed a cell-based screen of a library containing 2642 biologically active small-molecule compounds to identify modulators of claudin-4 expression. The screen identified 24 potential modulators of the claudin-4 promoter activity. Fourteen of these compounds (12 of them novel) induced endogenous claudin-4 expression. The identified compounds might serve as lead compounds targeting aberrant gene expression in inflammatory bowel disease.
    Biotechnology Letters 02/2015; 37(6). DOI:10.1007/s10529-015-1791-7 · 1.74 Impact Factor
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    ABSTRACT: Hepatitis C virus (HCV) entry into host cells is a complex process requiring multiple host factors, including claudin-1 (CLDN1). Safe and effective therapeutic entry inhibitors need to be developed. We isolated a human hepatic Huh7.5.1-derived cell mutant nonpermissive to HCV, and comparative microarray analysis showed that the mutant was CLDN1 defective. Four hybridomas were obtained, which produced monoclonal antibodies (mAbs) that interacted with the parental Huh7.5.1 cell but not with the CLDN1-defective mutant. All mAbs produced by these hybridomas specifically bound to human CLDN1 with very high affinity and prevented HCV infection of Huh7.5.1 cells in a dose-dependent manner, without apparent cytotoxicity. Two selected mAbs also inhibited HCV infection of human liver-chimeric mice without significant adverse effects. CLDN1 may be a potential target to prevent HCV infection in vivo. Anti-CLDN1 mAbs may hence be promising candidates as novel anti-HCV agents. Safe and effective therapeutic entry inhibitors against Hepatitis C virus (HCV) are very useful for combination therapies with other anti-HCV drugs such as direct-acting antivirals. In this study, we first showed the effective strategy to develop functional monoclonal antibodies (mAbs) against extracellular domains of a multimembrane-spanning target protein, claudin-1 (CLDN1), using parental cells expressing the intact target membrane protein and the target-defective cells. The established mAbs against CLDN1, which had very high affinity with intact CLDN1, efficiently inhibited in vitro and in vivo HCV infection. These anti-CLDN1 mAbs are promising leads for novel entry inhibitors against HCV. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
    Journal of Virology 02/2015; 89(9). DOI:10.1128/JVI.03676-14 · 4.65 Impact Factor
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    ABSTRACT: Claudin-1 (CLDN1), a known host factor for hepatitis C virus (HCV) entry and cell-to-cell transmission, is a target molecule for inhibiting HCV infection. We previously developed 4 clones of mouse anti-CLDN1 monoclonal antibody (mAb) that prevented HCV infection in vitro. Two of these mAbs showed the highest anti-viral activity. Here, we optimized the anti-CLDN1 mAbs as candidates for therapeutics by protein engineering. Although Fab fragments of the mAbs prevented in vitro HCV infection, their inhibitory effects were much weaker than those of the whole mAbs. In contrast, human chimeric IgG1 mAbs generated by grafting the variable domains of the mouse mAb light and heavy chains inhibited in vitro HCV infection as efficiently as the parental mouse mAbs. However, the chimeric IgG1 mAbs activated Fcγ receptor, suggesting that cytotoxicity against mAb-bound CLDN1-expressing cells occurred through the induction of antibody-dependent cellular cytotoxicity (ADCC). To avoid ADCC-induced side effects, we prepared human chimeric IgG4 mAbs. The chimeric IgG4 mAbs did not activate Fcγ receptor or induce ADCC, but they prevented in vitro HCV infection as efficiently as did the parental mouse mAbs. These findings indicate that IgG4 form of human chimeric anti-CLDN1 mAb may be a candidate molecule for clinically applicable HCV therapy. The American Society for Pharmacology and Experimental Therapeutics.
    Journal of Pharmacology and Experimental Therapeutics 01/2015; 353(1). DOI:10.1124/jpet.114.217653 · 3.86 Impact Factor
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    ABSTRACT: Homoharringtonine (HHT), a natural alkaloid produced by various Cephalotaxus species, has antileukemic activity in acute and chronic myelogenous leukemia. However, HHT can also induce unanticipated effects in the gastrointestinal tract, such as diarrhea and nausea/vomiting, but the mechanism behind these adverse effects has not been clarified. In the present study, we show that HHT affects the epithelial permeability of intestinal Caco-2 cell monolayers. HHT reduced the transepithelial electrical resistance (TER) of Caco-2 cells in a dose- and time-dependent manner. The HHT effect was reversible and no cytotoxicity was observed at the concentrations used. HHT simultaneously increased the paracellular flux of the 4 kDa and 40 kDa FITC-dextrans associated with the TER reduction. Immunoblotting analysis revealed that HHT decreased the protein expression of TJ components such as claudin-3, -5, and -7. However, the transcription levels of these claudins were not repressed by HHT treatment. HHT also disturbed the cellular localization of claudin-1 and -4. These changes coincided with the reduced barrier function. Our findings suggest that HHT enhances the paracellular permeability of Caco-2 cell monolayers by modulating the protein expression and localization of claudin isoforms; these actions might be responsible for the gastrointestinal effects of HHT.
    European Journal of Pharmaceutics and Biopharmaceutics 12/2014; 89. DOI:10.1016/j.ejpb.2014.12.012 · 4.25 Impact Factor
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    ABSTRACT: Most malignant tumors are derived from epithelium, and claudin (CLDN)-3 and -4 are frequently overexpressed in such tumors. Although antibodies have potential in cancer diagnostics and therapy, development of antibodies against CLDNs has been difficult because the extracellular domains of CLDNs are too small and there is high homology among human, rat, and mouse sequences. Here, we created a monoclonal antibody that recognizes human CLDN-3 and -4 by immunizing rats with a plasmid vector encoding human CLDN-4. A hybridoma clone that produced a rat monoclonal antibody recognizing both CLDN-3 and -4 (clone 5A5) was obtained from a hybridoma screen by using CLDN-3- and -4-expressing cells; 5A5 did not bind to CLDN-1, -2, -5, -6, -7 or -9-expressing cells. Fluorescence-conjugated 5A5 injected into xenograft mice bearing human cancer MKN74 or LoVo cells could visualize the tumor cells. The human-rat chimeric IgG1 monoclonal antibody (xi5A5) activated FcgammaRIIIa in the presence of CLDN-3- or -4-expressing cells, indicating that xi5A5 may exert antibody-dependent cellular cytotoxicity. Administration of xi5A5 attenuated tumor growth in xenograft mice bearing MKN74 or LoVo cells. These results suggest that 5A5 shows promise in the development of a diagnostic and therapeutic antibody for cancers.
    Journal of Pharmacology and Experimental Therapeutics 08/2014; 351(1). DOI:10.1124/jpet.114.216911 · 3.86 Impact Factor
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    ABSTRACT: Diacylglycerol acyltransferase-1 (DGAT1) is involved in the assembly of hepatitis C virus (HCV) by facilitating the trafficking of the HCV core protein to the lipid droplet. Here, we abrogated DGAT1 expression in Huh-7.5 cells using either the transcription activator-like effector nuclease (TALEN) or shRNA-lentivirus, and achieved complete, long-term silencing of DGAT1. HCV entry was severely impaired in DGAT1-silenced Huh-7.5 cell lines, which showed markedly diminished claudin-1 (CLDN1) expression. In DGAT1-silenced cell lines, the forced expression of CLDN1 restored HCV entry, implying that the downregulation of CLDN1 is a critical factor underlying defective HCV entry. The expression of hepatocyte nuclear factor 4α (HNF4α) and other hepatocyte-specific genes was also reduced in DGAT1-silenced cell lines. After DGAT1 gene rescue, CLDN1 expression was preserved, and HCV entry was restored. Strikingly, after DGAT1 silencing, CLDN1 expression and HCV entry were also restored by low dose palmitic acid treatment, indicating that the downregulation of CLDN1 was associated with altered fatty acid homeostasis in the absence of DGAT1. Our findings provide novel insight into the role of DGAT1 in the life cycle of HCV.
    Journal of Virology 06/2014; 88(16). DOI:10.1128/JVI.01428-14 · 4.65 Impact Factor
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    ABSTRACT: The molecular basis of endothelial cell (EC)-specific gene expression is poorly understood. Roundabout 4 (Robo4) is expressed exclusively in ECs. We previously reported that the 3-kb 5'-flanking region of the human Robo4 gene contains information for lineage-specific expression in the ECs. Our studies implicated a critical role for GA-binding protein and SP1 in mediating overall expression levels. However, these transcription factors are also expressed in non-ECs. In this study, we tested the hypothesis that epigenetic mechanisms contribute to EC-specific Robo4 gene expression.
    Arteriosclerosis Thrombosis and Vascular Biology 05/2014; 34(7). DOI:10.1161/ATVBAHA.114.303818 · 5.53 Impact Factor
  • The FASEB Journal 04/2014; 28(1). · 5.48 Impact Factor
  • The FASEB Journal 04/2014; 28(1). · 5.48 Impact Factor
  • The FASEB Journal 04/2014; 28(1). · 5.48 Impact Factor
  • The FASEB Journal 04/2014; 28(1). · 5.48 Impact Factor
  • Masuo Kondoh · Jun Kunisawa
    YAKUGAKU ZASSHI 01/2014; 134(5):613. DOI:10.1248/yakushi.14-00006-F · 0.31 Impact Factor
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    ABSTRACT: Most pathogens invade body through the mucosal epithelium, which is a primary target to prevent the infectious diseases. Mucosal vaccine has been considered to be an effective strategy to establish immunosurveillance against pathogens by the induction of antigen-specific immune responses at both mucosal and systemic immune compartments. The development of antigen delivery system and mucosal adjuvants are required for the sufficient induction of protective immunity in the development of mucosal vaccine. In this review, we shed light on the recent advances in the development of antigen delivery system using microbial functions for mucosal vaccines.
    YAKUGAKU ZASSHI 01/2014; 134(5):629-634. DOI:10.1248/yakushi.14-00006-3 · 0.31 Impact Factor
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    ABSTRACT: Epithelium plays pivotal roles in biological barrier separating the inside of body and the outside environment. Ninety percent of malignant tumors are derived from epithelium. Most pathological microorganisms invade into the body from mucosal epithelium. Thus, epithelium is potential targets for drug development. Claudins (CLs), a family of tetra-transmembrane protein consisting of over 20 members, are structural and functional components of tight junction-seals in epithelium. Modulation of CL-seals enhanced mucosal absorption of drugs. CLs are often over-expressed in malignant tumors. CL-4 expression is increased in the epithelial cells covering the mucosal immune tissues. Very recently, CLs are also expected to be targets for traumatic brain injury and regenerative therapy. In this review, we overview the past, the present and the future of CLs-targeted drug development.
    YAKUGAKU ZASSHI 01/2014; 134(5):641-645. DOI:10.1248/yakushi.14-00006-5 · 0.31 Impact Factor
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    ABSTRACT: We previously found that claudin (CL) is a potent target for cancer therapy using a CL-3 and -4-targeting molecule, namely the C-terminal fragment of Clostridium perfringens enterotoxin (C-CPE). Although CL-3 and -4 are expressed in various normal tissues, the safety of this CL-targeting strategy has never been investigated. Here, we evaluated the tissue distribution of C-CPE in mice. Ten minutes after intravenous injection into mice, C-CPE was distributed to the liver and kidney (24.0% and 9.5% of the injected dose, respectively). The hepatic level gradually fell to 3.2% of the injected dose by 3 h post-injection, whereas the renal C-CPE level gradually rose to 46.5% of the injected dose by 6 h post-injection and then decreased. A C-CPE mutant protein lacking the ability to bind CL accumulated in the liver to a much lesser extent (2.0% of the dose at 10 min post-injection) than did C-CPE, but its renal profile was similar to that of C-CPE. To investigate the acute toxicity of CL-targeted toxin, we intravenously administered C-CPE-fused protein synthesis inhibitory factor to mice. The CL-targeted toxin dose-dependently increased the levels of serum biomarkers of liver injury, but not of kidney injury. Histological examination confirmed that injection of CL-targeted toxin injured the liver but not the kidney. These results indicate that potential adverse hepatic effects should be considered in C-CPE-based cancer therapy.
    European journal of pharmaceutical sciences: official journal of the European Federation for Pharmaceutical Sciences 11/2013; 52. DOI:10.1016/j.ejps.2013.10.018 · 3.01 Impact Factor
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    ABSTRACT: Platinum nanoparticles are being utilized in various industrial applications, including in catalysis, cosmetics, and dietary supplements. Although reducing the size of the nanoparticles improves the physicochemical properties and provides useful performance characteristics, the safety of the material remains a major concern. The aim of the present study was to evaluate the biological effects of platinum particles less than 1 nm in size (snPt1). In mice administered with a single intravenous dose of snPt1, histological analysis revealed necrosis of tubular epithelial cells and urinary casts in the kidney, without obvious toxic effects in the lung, spleen, and heart. These mice exhibited dose-dependent elevation of blood urea nitrogen, an indicator of kidney damage. Direct application of snPt1 to in vitro cultures of renal cells induced significant cytotoxicity. In mice administered for 4 weeks with twice-weekly intraperitoneal snPt1, histological analysis of the kidney revealed urinary casts, tubular atrophy, and inflammatory cell accumulation. Notably, these toxic effects were not observed in mice injected with 8-nm platinum particles, either by single- or multiple-dose administration. Our findings suggest that exposure to platinum particles of less than 1 nm in size may induce nephrotoxicity and disrupt some kidney functions. However, this toxicity may be reduced by increasing the nanoparticle size.
    Nanoscale Research Letters 09/2013; 8(1):395. DOI:10.1186/1556-276X-8-395 · 2.52 Impact Factor

Publication Stats

2k Citations
440.02 Total Impact Points

Institutions

  • 1998–2015
    • Osaka University
      • • Laboratory of Bio-Function Molecular Chemistry
      • • Graduate School of Pharmaceutical Sciences
      • • Division of Molecular Pharmaceutical Science
      Suika, Ōsaka, Japan
  • 2002–2013
    • Showa Pharmaceutical University
      Machida, Tōkyō, Japan
  • 2011
    • Tokyo Medical and Dental University
      Edo, Tōkyō, Japan
    • Osaka University of Pharmaceutical Sciences
      • Graduate School of Pharmaceutical Sciences
      Ōsaka, Ōsaka, Japan
  • 1999–2010
    • Tokushima Bunri University
      • Faculty of Pharmaceutical Sciences
      Tokusima, Tokushima, Japan