K Izuhara

Kyushu University, Hukuoka, Fukuoka, Japan

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Publications (52)178.08 Total impact

  • Y Watanabe · Y Yamaguchi · N Komitsu · S Ohta · Y Azuma · K Izuhara · M Aihara
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    ABSTRACT: Background: Squamous cell carcinoma antigen (SCCA) belongs to the ovalbumin-serpin family and is a known tumour marker. Expression of SCCA is up-regulated in serum and skin of psoriasis patients. Objectives: The aim of this study was to determine SCCA2 levels in association with disease severity and treatment efficacy in patients with psoriasis. Methods: One hundred twenty-three psoriasis patients and 25 healthy controls were enrolled in this prospective cross-sectional study. Enzyme-linked immunosorbent assay (ELISA) analysis was performed to determine serum SCCA2 levels. SCCA2 expression in skin was evaluated using immunohistochemical analysis. Serum SCCA2 levels were compared with psoriasis area severity index (PASI) scores. The effect of treatment on serum SCCA2 levels was assessed using serial examinations. Induction of SCCA2 by several psoriatic cytokines in human keratinocytes was evaluated. Results: The serum levels of SCCA2 were significantly higher in patients with psoriasis than healthy controls and well correlated with disease severity. Increased SCCA2 staining was observed in lesional skin but not in non-lesional skin of psoriasis patients. In addition, SCCA2 expression levels in skin correlated with serum concentrations of SCCA2. SCCA2 significantly decreased according to improvement of PASI scores. IL-17 and IL-22 synergistically increased the production of SCCA2 at both mRNA and protein levels in human keratinocytes. Conclusion: Significant elevation of SCCA2 is associated with disease severity and reflects treatment efficacy. SCCA2 may be a useful biomarker in psoriasis, reflecting Th17-type inflammation-the main determinant of the severity of psoriasis. This article is protected by copyright. All rights reserved.
    No preview · Article · Jan 2016 · British Journal of Dermatology
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    ABSTRACT: Asthma is a complex clinical syndrome characterized by variable airflow obstruction (some of which can be permanent), airway hyperresponsiveness (AHR), and cellular inflammation. It is a heterogeneous disorder, exhibiting multiple phenotypes, reflected by the many clinical aspects of the disease (1-5). Recent advances in the identification of serum biomarkers for asthma are important in its diagnosis, including determination of the asthma phenotype or endotype. Woodruff et al. emphasized the utility of periostin as a biomarker of TH 2-induced airway inflammation (6). This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    No preview · Article · Feb 2015 · Allergy
  • S. Ohta · K. Izuhara

    No preview · Article · Jan 2015 · Japanese Journal of Clinical Chemistry
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    Kenji Izuhara

    Preview · Article · Jun 2014 · Allergology International
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    ABSTRACT: In steroid-naive patients with asthma, several gene variants are associated with a short-term response to inhaled corticosteroid (ICS) treatment; this has mostly been observed in Caucasians. However, not many studies have been conducted for other ethnicities. Here, we aimed to determine the relationship between the annual decline in forced expiratory flow volume in one second (FEV1 ) and the variant of the glucocorticoid-induced transcript 1 gene (GLCCI1) in Japanese patients with asthma receiving long-term ICS treatment, taking into account the effect of high serum periostin levels, a known association factor of pulmonary function decline and a marker of refractory eosinophilic/Th2 inflammation. In this study, 224 patients with asthma receiving ICS treatment for at least 4 years were enrolled. The effects of single-nucleotide polymorphisms (SNPs) in GLCCI1, stress-induced phosphoprotein 1 (STIP1), and T gene on the decline in FEV1 of 30 ml/year or greater were determined. Besides the known contributing factors, that is, the most intensive treatment step, ex-smoking, and high serum periostin levels (≥95 ng/ml), the GG genotype of GLCCI1 rs37973, and not other SNPs, was independently associated with a decline in FEV1 of 30 ml/year or greater. When patients were stratified according to their serum periostin levels, the GG genotype of rs37973 was significantly associated with blood eosinophilia (≥250/μl) in the high serum periostin group. A GLCCI1 variant is a risk factor of pulmonary function decline in Japanese patients with asthma receiving long-term ICS treatment. Thus, GLCCI1 may be associated with response to ICS across ethnicities.
    No preview · Article · Mar 2014 · Allergy
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    ABSTRACT: Background Recent findings indicate that periostin, an extracellular matrix protein induced by T helper 2 cytokines, plays a critical role in the pathogenesis of atopic dermatitis (AD). Objectives To determine whether serum periostin level is associated with clinical phenotype in adult patients with AD. Methods An enzyme-linked immunosorbent assay was performed to determine serum periostin levels in 257 adult patients with AD, 66 patients with psoriasis vulgaris (PV) as a disease control and 25 healthy controls. Serum periostin levels were analysed together with clinical characteristics and laboratory parameters, including thymus and activation-regulated chemokine (TARC), lactate dehydrogenase (LDH), blood eosinophil count and total IgE. Immunohistochemical analysis evaluated the expression of periostin in association with various clinical phenotypes of AD. The effect of treatment on serum periostin level was also assessed. Results Serum periostin was significantly higher in patients with AD than in patients with PV and healthy controls. Periostin level was found to be positively correlated with disease severity, TARC level, LDH level and eosinophil count, but not with IgE level. Higher serum periostin level was observed in patients with extrinsic AD compared with patients with intrinsic AD; the positive correlation of disease severity disappeared in patients with intrinsic AD. Robust expression of periostin was detected in the dermis of patients with AD with erythroderma, lichenification and, to a lesser extent, scaly erythema. Serial measurement of serum periostin revealed decreased levels of periostin after treatment for AD. Conclusions Periostin may play a critical role in disease severity and chronicity in the pathogenesis of AD.
    No preview · Article · Mar 2014 · British Journal of Dermatology
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    Kenji Matsumoto · Kenji Izuhara

    Preview · Article · Mar 2014 · Allergology International
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    ABSTRACT: Atopic dermatitis (AD) is a chronic inflammatory skin disease. Here, we show that phospholipase C-β3 (PLC-β3)-deficient mice spontaneously develop AD-like skin lesions and more severe allergen-induced dermatitis than wild-type mice. Mast cells were required for both AD models and remarkably increased in the skin of Plcb3(-/-) mice because of the increased Stat5 and reduced SHP-1 activities. Mast cell-specific deletion of Stat5 gene ameliorated allergen-induced dermatitis, whereas that of Shp1 gene encoding Stat5-inactivating SHP-1 exacerbated it. PLC-β3 regulates the expression of periostin in fibroblasts and TSLP in keratinocytes, two proteins critically involved in AD pathogenesis. Furthermore, polymorphisms in PLCB3, SHP1, STAT5A, and STAT5B genes were associated with human AD. Mast cell expression of PLC-β3 was inversely correlated with that of phospho-STAT5, and increased mast cells with high levels of phospho-STAT5 were found in lesional skin of some AD patients. Therefore, STAT5 regulatory mechanisms in mast cells are important for AD pathogenesis.
    Full-text · Article · Jan 2014 · Cell Reports
  • S. Ohta · K. Izuhara
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    ABSTRACT: The interstitial pneumonias are a diverse group of pulmonary disorders with interstitial fibrous lesions. There is no curative treatment especially for patients with idiopathic pulmonary fibrosis. The survival time after diagnosis of idiopathic pulmonary fibrosis is only a few years. One can only maintain the current condition by using corticosteroids, which is not that effective to the disease. Early diagnosis and treatment may contribute to the maintenance of the quality of life although definitive diagnosis of interstitial pneumonia involves some difficulties. We have developed several enzyme-linked immunosorbent assay systems to measure serum periostin, an extracellular matrix component, with much higher sensitivity and specificity than the previous assays. These assays are useful for diagnosis and prediction of prognosis of interstitial pneumonia, and periostin, therefore, is expected to be its novel biomarker in the clinical settings.
    No preview · Article · Oct 2013 · Japanese Journal of Clinical Chemistry

  • No preview · Article · May 2013 · Annals of allergy, asthma & immunology: official publication of the American College of Allergy, Asthma, & Immunology
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    ABSTRACT: Background:  Periostin, a matricellular protein, serves as a regulator of wound healing and fibrosis. The role of periostin in the pathogenesis of systemic sclerosis (SSc) is unknown. Objective:  To determine periostin levels in association with severity of skin fibrosis in patients with SSc. Methods:  Expression of periostin was immunohistochemically examined in the skin obtained from SSc patients and healthy controls. Enzyme-linked immunosorbent assay was performed to evaluate serum periostin levels in association with clinical characteristics in 56 patients with SSc (diffuse cutaneous SSc (dSSc), n=16; and limited cutaneous SSc (lSSc), n=40) and 66 healthy controls. Results:  Periostin was strongly expressed in the affected dermis from SSc patients. Periostin was co-localized in α-SMA-positive myofibroblasts and PECAM-1-positive endothelial cells in SSc dermis. Serum levels of periostin in dSSc patients were markedly elevated compared to those in lSSc patients and control subjects. Patients with lSSc had increased periostin levels compared with healthy controls. In addition, significantly higher levels of periostin were observed in dSSc patients with disease duration ≤5 years compared with those with disease duration >5 years. Furthermore, the modified Rodnan total skin thickness score (MRSS) was positively correlated with periostin levels in SSc patients. Serial analysis revealed a correlation between periostin and MRSS; namely, MRSS decreased in line with decreased periostin levels in some dSSc patients as the disease progressed. Conclusion:  An elevated periostin level in SSc patients was associated with severity of skin sclerosis. Periostin may be a potential biomarker for progressive skin fibrosis in SSc.
    No preview · Article · Oct 2012 · British Journal of Dermatology
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    ABSTRACT: We investigated the localization of periostin in middle ear specimens from patients with eosinophilic otitis media (EOM) and from a newly constructed animal model for EOM. Periostin-positive immunostaining was observed in the middle ear sections obtained from the EOM patients. Immunoreactivity for periostin was also seen in the animal model. These results suggest that periostin plays an important role in subepithelial fibrosis in the middle ear in EOM. The purpose of the present study was to investigate the role of periostin in the middle ear of EOM patients and an animal model. Histological and immunohistochemical analyses for periostin were carried out in the middle ear specimens of six EOM patients with/without asthma. An animal model of EOM was constructed by intraperitoneal and topical sensitization with ovalbumin (OVA). Histological and immunocytochemical analyses for periostin were also performed in this model. Immunoreactivities for periostin were observed in the basement membrane and extracellular matrix of the middle ear sections obtained from all EOM patients with/without asthma. In the animal model, eosinophil infiltration and middle ear mucosa thickness were observed. Moreover, periostin-positive immunostaining was shown in the extracellular matrix of the middle ear mucosa on the side topically boosted by OVA.
    No preview · Article · Jun 2012 · Acta oto-laryngologica
  • K. Izuhara · K. Arima · S. Suzuki · H. Shiraishi · S. Ohta

    No preview · Article · Feb 2012 · Kokyu to junkan. Respiration & circulation
  • K. Izuhara · S. Ohta · H. Shiraishi · S. Suzuki

    No preview · Article · Jul 2011
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    ABSTRACT: May-Hegglin anomaly (MHA) is a rare autosomal dominant disease characterized by macrothrombocytopenia and leukocyte inclusions with microfilaments in the ribosomes. Mutations in the MYH9 gene, encoding non-muscle myosin heavy chain IIA (NMMHC-IIA) have been identified in patients with MHA and other MYH9-related diseases. Two young males (an older and younger brother) presented with macrothrombocytopenia and leukocyte inclusion bodies. Electron microscopy (EM) revealed parallel filaments in leukocyte inclusion bodies characteristic of MHA. Immunofluorescence microscopy (IF) showed NMMHC-IIA antibodies in 1 - 2 leukocyte inclusion bodies. These findings were consistent with MHA and they were identified to express the MYH9 mutation, D1424H. The older brother underwent a renal biopsy because of persistent proteinuria. Histology revealed mesangial proliferative glomerulonephritis with granular deposits of IgG and C1q. EM showed that the dense deposits were located in subendothelial cells, mesangial cells and Bowman's capsule. Immunocytochemistry revealed that NMMHC-IIA antibodies were localized in podocyte and endothelial cells in the glomerulus. Moreover, the expression of nephrin and podocin, slit diagram protein, was normal. An inflammatory mechanism may occur separately from MYH9-related disease. This report presents a case of MHA with immune complex-related nephropathy.
    No preview · Article · Mar 2011 · Clinical nephrology
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    ABSTRACT: Idiopathic interstitial pneumonias (IIPs) are histopathologically classified into several types, including usual interstitial pneumonia (UIP), nonspecific interstitial pneumonia (NSIP) and cryptogenic organising pneumonia (COP). We investigated whether periostin, a matrix protein, could be used as a biomarker to assess histopathological types of IIPs. We performed immunohistochemical analyses in each histopathological type of IIP, examined serum levels of periostin in IIP patients and analysed the relationship between serum levels of periostin and the pulmonary functions in patients with idiopathic pulmonary fibrosis (IPF). Periostin was strongly expressed in lungs of UIP and fibrotic NSIP patients, whereas expression of periostin was weak in the lungs of cellular NSIP and COP patients, as well as in normal lungs. Serum levels of periostin in IPF were significantly higher than those of healthy subjects and COP patients. Furthermore, periostin levels in IPF patients were inversely correlated with their pulmonary functions. Thus, we have found that periostin is a novel component of fibrosis in IIP. Periostin may be a potential biomarker to distinguish IIP with fibrosis.
    No preview · Article · Dec 2010 · European Respiratory Journal
  • K Izuhara

    No preview · Article · May 2009 · Cellular and Molecular Life Sciences CMLS
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    ABSTRACT: Mucus production is a cardinal feature of bronchial asthma, contributing to morbidity and mortality in the disease. Goblet cells are major mucus-producing cells, and goblet cell hyperplasia (GCH) is one feature of airway remodeling, defined as structural changes occurring in the airway. A number of studies have demonstrated that Th2-type cells play critical roles in this process and that particularly interleukin-13 (IL-13), among Th2-type cytokines, is a central mediator for GCH. However, the mechanism underlying how Th2 cytokines induce mucus production or GCH is poorly understood. Mouse calcium-activated chloride channel-3 (mCLCA-3; gob-5)/human CLCA-1 acts as a downstream molecule of Th2 cytokines, IL-4/IL-9/IL-13 signals, playing an important role in mucus production. Moreover, we have recently found that pendrin, an anion transporter, is induced by IL-13 and causes mucus production in airway epithelial cells. It is hoped that if we can clarify how mucus is produced, this will lead to development of novel therapeutic reagents to suppress mucus production in bronchial asthma.
    No preview · Article · Feb 2009 · Current Medicinal Chemistry
  • K Izuhara · S Ohta · S Kanaji · H Shiraishi · K Arima
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    ABSTRACT: The inhibitory mechanism against proteases is important in the maintenance of homeostasis or health in the body. The human ovalbumin serpin (ov-serpin)/clade B serpin family is one group of the human serpins, a family of serine protease inhibitors. They have acquired diversity in the profiles of target proteases, inhibitory mechanisms, and localization patterns during their evolution. Most serpins target serine proteases, however, some ov-serpins target only cysteine proteases or both serine and cysteine proteases and furthermore, several ov-serpins do not possess inhibitory activities. Although the ov-serpins act primarily as intracellular serpins, some show extracellular and nuclear localizations. Such diversity enables the ov-serpins to play multiple physiological roles in the body. Recent analyses have revealed that the functions of human ov-serpins are more diversified than we previously knew. In this article, we describe recent progress in our understanding of how the human ov-serpin/clade B serpin family demonstrates diversity.
    No preview · Article · Jul 2008 · Cellular and Molecular Life Sciences CMLS
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    K Izuhara · K Arima · S Kanaji · S Ohta · T Kanaji
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    ABSTRACT: The incidence of allergic diseases has dramatically increased in recent decades, especially in urban and industrialized areas. It is important socially as well as medically to establish more useful strategies to overcome allergic disorders. Bronchial asthma is a complex disease characterized by airway inflammation involving a Th2-cytokine, interleukin (IL)-13. A substantial body of evidence has accumulated pointing to the pivotal role of IL-13 in the pathogenesis of bronchial asthma, based on mainly analyses of mouse models. In addition to such analyses, the high expression of IL-13 in lesions and genetic association of several genes coding IL-13 signaling molecules with bronchial asthma have raised the possibility that IL-13 plays a pivotal role in the onset or exacerbation of human bronchial asthma. Therefore, IL-13 and its signal pathway are thought to be promising targets to develop a therapeutic agent for bronchial asthma. In this article, we describe how IL-13 is involved in the pathogenesis of bronchial asthma and then how therapeutic agents to block IL-13 signals are developed for bronchial asthma.
    Full-text · Article · Feb 2006 · Current Medicinal Chemistry

Publication Stats

2k Citations
178.08 Total Impact Points


  • 1997-2001
    • Kyushu University
      • • Department of Clinical Chemistry and Laboratory Medicine
      • • Graduate School of Medical Sciences
      • • Division of Internal Medicine
      Hukuoka, Fukuoka, Japan
  • 2000
    • Swansea University
      • Experimental Medicine Unit
      Swansea, Wales, United Kingdom
  • 1998
    • National Institute of Genetics
      • Division of Human Genetics
      Мисима, Shizuoka, Japan
  • 1993
    • Palo Alto Institute for Research and Education
      Palo Alto, California, United States
    • Molecular and Cellular Biology Program
      Seattle, Washington, United States