Yasuhiro Funada

Inhalation of urokinase-type plasminogen activator reduces airway remodeling in a murine asthma model

The airway remodeling that occurs in asthma is characterized by an excess of extracellular matrix deposition in the submucosa, hyperplasia/hypertrophy of smooth muscle, goblet cell metaplasia, and accumulation of fibroblasts/myofibroblasts. The urokinase-type plasminogen activator (uPA)/plasmin system participates in pericellular proteolysis and is capable of directly degrading matrix components, activating latent proteinases, and activating growth factors. In a mouse ovalbumin (OVA) asthma model, we increased plasminogen activator activity in the lung by administering exogenous uPA or by using mice genetically deficient in the uPA inhibitor plasminogen activator inhibitor-1 (PAI-1) to assess the role of this system in asthma pathogenesis. After intraperitoneal OVA sensitization, mice inhaled OVA plus uPA (500 IU/mouse) or saline by ultrasonic nebulization for 3 wk. When studied 24 h after the final exposure, the groups with upregulated plasmin activity had significantly reduced subepithelial fibrosis within the airway walls and had decreased airway hyperresponsiveness (AHR) to methacholine. Morphometric analysis showed that subepithelial wall thickening of the bronchi (subepithelial area ratio) was also reduced, as were collagen and alpha-smooth muscle actin. Upregulation of plasmin activity also increased the level of hepatocyte growth factor activity in bronchoalveolar lavage fluid, whereas the release of transforming growth factor-beta was decreased. The administration of uPA 1 wk after the last OVA inhalation also significantly reduced lung hydroxyproline content and AHR. These results show that enhancing uPA/plasmin activity lessens the airway remodeling in a murine asthma model.

The transfer of maternal antigen-specific IgG regulates the development of allergic airway inflammation early in life in an FcRn-dependent manner.

Asthma is a chronic inflammatory airway disease characterized by airway hyperreactivity, increased mucus production, and reversible airway contraction. Asthma is a complex genetic trait caused by environmental factors in genetically predisposed individuals. The transportation of maternal antigen-specific IgG via amniotic fluid, placenta and breast milk plays an important role in passive immunity. First, to examine whether maternal passive immunity by the transportation of antigen-specific IgG via FcRn regulates allergic airway inflammation, ovalbumin-immunized FcRn(+/-) female mice were bred with FcRn(-/-) male mice to evaluate the degree of ovalbumin-induced allergic airway inflammation of FcRn(-/-) offspring. Maternal passive immunity regulated allergic airway inflammation in an FcRn-dependent manner. Second, to examine the role of maternal antigen-specific IgG1 injection into mothers, we intravenously injected ovalbumin-specific IgG1 into wild-type or FcRn(+/-) mice immediately after they gave birth. The offspring were sensitized and challenged with ovalbumin. Antigen-specific IgG1 administered to lactating mice reduced allergic airway inflammation in their offspring in an FcRn-dependent manner. Last, to exclude the factor of maternal passive immunity other than ovalbumin-specific IgG1, we administered ovalbumin-specific IgG1 orally to offspring after birth. Oral administration of ovalbumin-specific IgG1 to offspring during the lactating period prevented the development of allergic airway inflammation in an FcRn-dependent manner. These data show that the transfer of maternal antigen-specific IgG regulates the development of allergic airway inflammation early in life in an FcRn-dependent manner.

Sphingosine kinase 1 regulates mucin production via ERK phosphorylation.

Our previous report showed that inhibition of sphingosine kinase (SphK) ameliorates eosinophilic inflammation and mucin production in a mouse asthmatic model. To clarify the role of SphK in airway mucin production, we utilized the mouse asthmatic model and found that both SphK and MUC5AC expression were increased and co-localized in airway epithelium. Next we cultured normal human bronchial epithelial cells in an air-liquid interface and treated with IL-13 to induce their differentiation into goblet cells. We found that SphK1 and MUC5AC expression was increased by IL-13 treatment at both protein and mRNA levels, whereas SphK2 expression was not changed. N,N-dimethylsphingosine (DMS), a potent SphK inhibitor, decreased MUC5AC expression up-regulated by IL-13 treatment. Furthermore, DMS inhibited IL-13-induced ERK1/2 phosphorylation but neither p38 MAPK nor STAT6 phosphorylation. These results suggest that SphK1 is involved in MUC5AC production induced by IL-13 upstream of ERK1/2 phosphorylation, and independent of STAT6 phosphorylation.

Airway remodeling of murine chronic antigen exposure model.

Airway remodeling is one of the most important features of bronchial asthma. However, there are few studies that have used repeated antigen exposure in murine models. We designed a murine chronic antigen exposure model necessary for studying airway remodeling. Two different strains of mice, BALB/c mice and C57BL/6 mice, were sensitized and challenged for 3–7 weeks with ovalbumin (OVA). Bronchoalveolar lavage (BAL) and histology study were conducted in each phase. Morphometry was performed, and the epithelial area ratio (Ae ratio) and subepithelial area ratio (As ratio) were calculated. The Ae ratio and As ratio of BALB/c mice were significantly increased in sensitized mice compared with nonsensitized mice at 3 and 5 weeks, but not at 7 weeks. In C57BL/6 mice, the Ae ratio showed no significant changes, whereas the As ratio maintained high from 3 to 7 weeks. This thickening of the subepithelial layer consisted of collagen fibers with elastica van‐Gieson (EVG) stain. Lymphocytes of the BAL showed a significant increase at 3 and 7 weeks in C57BL/6 mice, but not in BALB/c mice. A murine chronic OVA exposure model in C57BL/6 mice revealed subepithelial layer thickening consisting of collagen fibers and increased lymphocytes until 7 weeks. C57BL/6 mice are useful to elucidate the mechanism of airway remodeling.

Successful Crizotinib Rechallenge After Crizotinib-induced Interstitial Lung Disease

We report the case of a 70-year-old Japanese male diagnosed with advanced lung adenocarcinoma harboring the echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase fusion gene. As soon as crizotinib was administered, tumor shrank immediately. On Day 25, he developed interstitial lung disease. Bronchoalveolar lavage fluid analysis demonstrated elevated lymphocytes fractionation. A drug lymphocyte stimulating test for crizotinib with the bronchoalveolar lavage lymphocytes was negative. Crizotinib administration was discontinued, but a life-threatening flare of tumor growth occurred. Since there was no alternative treatment for the lung cancer, we restarted crizotinib in combination with prednisolone. The patient experienced neither disease progression nor recurrence of interstitial lung disease at 6 months. In cases in which no alternate treatment is known, crizotinib retreatment combined with steroid therapy after crizotinib-induced interstitial lung disease could be considered after a careful consideration of the potential risks and benefits.

Characteristics of Patients with Chronic Cough Who Developed Classic Asthma during the Course of Cough Variant Asthma: A Longitudinal Study

Background: Some patients develop asthmatic symptoms such as wheezing and dyspnea during the course of cough variant asthma (CVA), which are considered precursors of classical asthma. Objectives: To identify the characteristics of such patients, we investigated the nature of CVA patients with or without developing bronchial asthma in the longitudinal study. Methods: In 28 CVA patients whom we could observe over 5 years, duration of coughing, physical examination findings, pulmonary function and bronchial hyperresponsiveness to inhaled methacholine were retrospectively assessed. Results: Of these patients with CVA, 10 developed the asthmatic symptoms of wheezing and dyspnea (precursors of classical asthma) over 5 years. All these 10 patients showed marked bronchial hyperresponsiveness; however, there were no significant differences in the bronchial responsiveness to methacholine between patients with precursors of classical asthma and pure CVA patients who did not wheeze. The duration of coughing had a significant relationship with precursors of classical asthma. Seven patients with precursors of classical asthma developed wheezing in the first year and 1 patient each in the second, third and fourth year. Conclusions: These findings of a 5-year observation suggest that longer duration of coughing may be an important factor that develops precursors of classical asthma in patients with CVA.

Randomized Phase II Study of Two Different Schedules of Gemcitabine and Oral S-1 in Chemo-naïve Patients with Advanced Non-small Cell Lung Cancer

Introduction: This study was conducted to evaluate the efficacy and safety and to compare dosing schedules of gemcitabine combined with S-1 in chemo-naïve non-small cell lung cancer patients. Methods: Patients with chemo-naïve stage IIIB/IV non-small cell lung cancer were randomized into two treatment arms. Patients were given oral S-1 (60 mg/m2/d, twice a day) from days 1 to 14 with gemcitabine (1000 mg/m2/d) on days 1 and 8 (arm A) or on days 8 and 15 (arm B). This cycle was repeated every 21 days. Results: A total of 80 patients were entered in this trial. The primary end point of this study was response rate. The response rates of arm A and arm B were 22.0 and 28.9%, respectively (p = 0.606). Median time to treatment failure in arm A was 3.6 months and 4.8 months in arm B. Median time to progression in arm A was 4.1 months and 5.5 months in arm B. Median survival time in arm A and arm B was 15.5 months and 18.8 months, respectively. The toxicity profile was relatively mild and did not differ very much between two arms. Conclusion: The combination of gemcitabine and S-1 was determined to be feasible and effective for advanced non-small cell lung cancer. We selected arm B for further studies because of its higher response rate and survival data.

Antigen-Specific IgG ameliorates allergic airway inflammation via Fcγ receptor IIB on dendritic cells

BackgroundThere have been few reports on the role of Fc receptors (FcRs) and immunoglobulin G (IgG) in asthma. The purpose of this study is to clarify the role of inhibitory FcRs and antigen presenting cells (APCs) in pathogenesis of asthma and to evaluate antigen-transporting and presenting capacity by APCs in the tracheobronchial mucosa.MethodsIn FcγRIIB deficient (KO) and C57BL/6 (WT) mice, the effects of intratracheal instillation of antigen-specific IgG were analysed using the model with sensitization and airborne challenge with ovalbumin (OVA). Thoracic lymph nodes instilled with fluorescein-conjugated OVA were analysed by fluorescence microscopy. Moreover, we analysed the CD11c+ MHC class II+ cells which intaken fluorescein-conjugated OVA in thoracic lymph nodes by flow cytometry. Also, lung-derived CD11c+ APCs were analysed by flow cytometry. Effects of anti-OVA IgG1 on bone marrow dendritic cells (BMDCs) in vitro were also analysed. Moreover, in FcγRIIB KO mice intravenously transplanted dendritic cells (DCs) differentiated from BMDCs of WT mice, the effects of intratracheal instillation of anti-OVA IgG were evaluated by bronchoalveolar lavage (BAL).ResultsIn WT mice, total cells and eosinophils in BAL fluid reduced after instillation with anti-OVA IgG1. Anti-OVA IgG1 suppressed airway inflammation in hyperresponsiveness and histology. In addition, the number of the fluorescein-conjugated OVA in CD11c+ MHC class II+ cells of thoracic lymph nodes with anti-OVA IgG1 instillation decreased compared with PBS. Also, MHC class II expression on lung-derived CD11c+ APCs with anti-OVA IgG1 instillation reduced. Moreover, in vitro, we showed that BMDCs with anti-OVA IgG1 significantly decreased the T cell proliferation. Finally, we demonstrated that the lacking effects of anti-OVA IgG1 on airway inflammation on FcγRIIB KO mice were restored with WT-derived BMDCs transplanted intravenously.ConclusionAntigen-specific IgG ameliorates allergic airway inflammation via FcγRIIB on DCs.

Chemotherapy improves thymoma-associated graft-versus-host-disease-like erythroderma

Graft-versus-host-disease (GVHD) with erythroderma can rarely occur in the context of thymoma and is associated with a poor prognosis due to an increased risk of infection-related death. The present study describes a case of a 50-year-old man with malignant thymoma who developed sepsis in addition to skin manifestations similar to that seen in GVHD. This patient experienced marked improvement in skin lesions in response to steroids and combination chemotherapy with carboplatin and paclitaxel, with subsequent resolution of infection. The present study describes the clinical course of this patient, followed by a review of pertinent reports of thymoma associated with GVHD with particular focus on the efficacy of treatment strategies.

Ewing's sarcoma family of tumors originating in the main bronchus

Ewings sarcoma family tumors (ESFT), which include Ewings sarcoma and primitive neuroectodermal tumors (PNET), have been reported to originate in a variety of sites, mostly in the extremities. Previous reports have shown ESFT originating in the thoracic region, such as chest wall and peripheral lung. We herein report the first case of the ESFT that originated in the main bronchus. Endobronchial snare resection was followed by five courses of chemotherapy (VDC‐IE; including vincristine, doxorubicin, cyclophosphamide, ifosfamide and etoposide) and sequential radiation. After the treatment, the patients condition has improved, and he has remained disease‐free for the past year.