Eosinophilic otitis media (EOM) is an intractable otitis media characterized by the presence of a highly viscous yellow effusion containing eosinophils. It mainly occurs in patients with bronchial asthma and is resistant to conventional treatments for otitis media. Here we discuss the role of IgE in the pathogenesis of EOM. In middle ear effusion, a significantly higher IgE level was detected in EOM patients than in control patients with common otitis media with effusion. This IgE level was significantly higher (about 10 fold) than the serum IgE level. In addition, many IgE-immunopositive cells were found in the middle ear mucosa. The IgE staining was mainly observed on mast cell surfaces, but also partially in the cytoplasm of cells that appeared to be plasma cells. These results suggested that IgE is produced locally in the middle ear mucosa. The existence of high-level IgE may exacerbate eosinophilic inflammation in the middle ear. One of the most distinct characteristics of EOM is the high incidence of sensory hearing loss independent of age. High-tone hearing loss is more frequently found and more severe in EOM patients than in control patients with common chronic otitis media. The concentration of IgE in middle ear effusion significantly and positively correlated with bone conduction hearing levels at 2kHz and 4kHz in EOM patients. Overproduction of IgE locally in the middle ear may be related to the pathological condition of EOM and eventually cause inner ear damage.

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Chronic rhinosinusitis is a heterogeneous disease. In Europe and the United States, it has recently been divided into two subgroups: chronic rhinosinusitis with nasal polyps (CRSwNP) and chronic rhinosinusitis without nasal polyps (CRSsNP). The majority of CRSwNP cases have a strong tendency to recur after surgery and show eosinophil-dominant inflammation. However, this definition has proved difficult to apply in Japan and East Asia, because more than half of the CRSwNP cases do not exhibit eosinophil-dominant inflammation in these areas of the world. In Japan in the 1990s, refractory CRSwNP to the standard treatment was focused on in clinical studies and the term "eosinophilic chronic rhinosinusitis" (ECRS) was introduced to identify this subgroup of chronic rhinosinusitis in 2001.
ECRS is different from non-ECRS in terms of many clinical features: symptom appearance, occurrence site of nasal polyps, CT scan findings, the histology of nasal polyps, blood examination findings, clinical course after surgery, and co-morbid asthma, etc. In this review, we describe these clinical features and mention how to make a clinical diagnosis of ECRS as well as how to treat it. Finally, we discuss the pathophysiology of ECRS. The concept of ECRS in Japan would be applicable for CRSwNP in other countries including Europe and the United States.

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The overall pathological view of paranasal sinus inflammation in the Japanese population has profoundly changed in recent years. Eosinophilic chronic rhinosinusitis (ECRS) is a clinical entity of intractable chronic sinus inflammation accompanied by numerous infiltrations of activated eosinophils in the paranasal sinus mucosa and/or nasal polyps. Several pathologic processes are considered to act in concert to promote the accumulation of eosinophils in ECRS. They include infiltration of progenitor cells, increase in local IL-3, IL-5, IL-13, GM-CSF and eotaxin production, and upregulation of adhesion molecules. The role of nasal allergen sensitization and innate immunity responses in the sinus mucosa has also been proposed in the development of ECRS. Various pathogens including TLRs ligands may trigger an abnormal immune response at the mucosal surface. The objectives of ECRS management should focus directly on inhibition of local eosinophil infiltration. Surgical procedures include widely opening the bony wall septum of every affected sinus and mechanical removal of diseased mucosal lesion. The use of local and/or systemic steroids, leukotriene receptor antagonists, and Th2 cytokine antagonists is recommended. Local administration of steroids is a potent treatment strategy for preventing relapse of nasal polyposis and is considered to be the first-line treatment for ECRS patients.

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Asthma and chronic obstructive pulmonary disease (COPD) are chronic respiratory disorders involving obstructive airway defects. There have been many discussions on their similarities and differences. Although airflow limitation expressed as forced expiratory volume in one second (FEV₁) has been considered to be the main diagnostic assessment in both diseases, it does not reflect the functional impairment imparted to the patients by these diseases. Therefore, multidimensional approaches using multiple measurements in assessing disease control or severity have been recommended, and multiple endpoints in addition to FEV₁ have been set recently in clinical trials so as not to miss the overall effects. In particular, as improving symptoms and health status as well as pulmonary function are important goals in the management of asthma and COPD, some patient-reported measurements such as health-related quality of life or dyspnea should be included. Nonetheless, there have been few reviews on the long-term clinical course comparing asthma and COPD as predicted by measurements other than airflow limitation. Here, we therefore analyzed and compared longitudinal changes in both physiological measurements and patient-reported measurements in asthma and COPD. Although both diseases showed similar long-term progressive airflow limitation similarly despite guideline-based therapies, disease progression was different in asthma and COPD. In asthma, patient-reported assessments of health status, disability and psychological status remained clinically stable over time, in contrast to the significant deterioration of these parameters in COPD. Thus, because a single measurement of airflow limitation is insufficient to monitor these diseases, multidimensional analyses are important not only for disease control but also for understanding disease progression in asthma and COPD.

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Background: Airway remodeling is a repair process occurring after airway injury; its primary histopathological features are subepithelial fibrosis and smooth muscle thickening of the bronchi. These histopathological changes are considered to occur due to bronchial smooth muscle cells (bSMC) that secrete extracellular matrix (ECM) proteins, which work as chemoattractants and influence cell migration. Therefore, we examined the interaction between bSMCs and ECM proteins in vitro for understanding the remodeling process in the bronchi.
Methods: bSMCs were cultured to collect a bSMC-conditioned medium. Using the bSMC-conditioned medium thus obtained, we performed a cell migration assay, characterized β integrin expression, and identified ECM proteins and matrix metalloproteinases by western blotting and gelatin zymography, respectively.
Results: The response of bSMC migration to bSMC-conditioned medium increased with time in culture, and fibronectin (FIB) was detected as a chemoattractant for bSMCs in bSMC-conditioned medium by western blot analysis and a cell migration assay using anti-FIB antibodies. The involvement of β1 integrin in the migration of bSMCs toward FIB contained in bSMC-conditioned medium was demonstrated by inhibition of cell migration using anti-β1 integrin antibodies. Expression of β1 integrin on bSMCs was confirmed by using a β-integrin-mediated cell adhesion array. In addition, metalloproteinases detected in bSMC-conditioned medium by gelatin zymography were suggested to be matrix metalloproteinase-1 and 2 by western blotting and amino acid sequencing.
Conclusions: Our results suggest that FIB and matrix metalloproteinases secreted from bSMCs might play major roles in bSMC migration in the process of airway remodeling.

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Background: Amphiregulin (AR) is expressed in Th2 cells, rather than Th1 cells, and plays an important role in Th2 cell/cytokine-mediated host defense against nematodes. We also found earlier that AR mRNA expression was strongly upregulated in inflamed tissue during Th2 cell/cytokine-mediated fluorescein isothiocyanate (FITC)-induced contact hypersensitivity (CHS), suggesting a contribution of AR to the induction of those responses.
Methods: To elucidate the role of AR in the induction of FITC- or dinitrofluorobenzene (DNFB)-induced CHS, AR-deficient mice were sensitized and/or challenged with FITC or DNFB epicutaneously. The levels of FITC-mediated skin dendritic cell (DC) migration and FITC-specific lymph node cell proliferation and cytokine production were assessed by flow cytometry, [3H]-thymidine incorporation and ELISA, respectively, after FITC sensitization. The degree of ear swelling, the activities of myeloperoxidase (MPO) and eosinophil peroxidase (EPO) in inflammatory sites and the levels of FITC-specific immunoglobulin (Ig) in sera were determined by histological analysis, colorimetric assay and ELISA, respectively, after FITC challenge.
Results: DC migration and FITC-specific lymph node cell proliferation and cytokine production were normal in the AR-deficient mice. Ear swelling, tissue MPO and EPO activities and FITC-specific serum Ig levels were also similar in AR-deficient and -sufficient mice.
Conclusions: Amphiregulin is not essential for the induction of FITC- or DNFB-induced CHS responses in mice.

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Background: Indacaterol is an investigational, novel, inhaled once-daily ultra-long-acting beta-2 agonist for the treatment of chronic obstructive pulmonary disease (COPD). This study evaluated the 24-h bronchodilatory efficacy and safety of indacaterol in Japanese patients with COPD.
Methods: This Phase-II, randomised, placebo-controlled, crossover study comprised four double-blind, single-dose treatment periods (washout between periods: 14-28 days). Japanese patients aged 40-75 years with moderate-to-severe COPD were randomised to receive single doses of indacaterol (150, 300, or 600μg) or placebo via a single-dose dry-powder inhaler. Efficacy (primary endpoint: standardised FEV₁AUC_22-24h) and safety were assessed for 24 h post-dose in each treatment period.
Results: Of the 50 patients randomised (92% male; mean age, 67.2 years), 45 completed the study. Standardised FEV₁AUC_22-24h was significantly higher for all indacaterol doses as compared with placebo, with clinically relevant differences of 130, 160, and 170mL for 150, 300, and 600μg, respectively (P < 0.001). The improvement in FEV₁ was seen as early as 5 min post-dose with indacaterol and sustained for 24 h (P < 0.001 vs placebo at all time points). All indacaterol doses were well tolerated and showed no clinically meaningful effect on pulse rate, blood pressure, QTc interval, and laboratory parameters when compared with placebo.
Conclusions: In the Japanese COPD population studied, single doses of indacaterol (150, 300, and 600μg) provided sustained 24-h bronchodilation, with onset of action within 5 min post-dose. All doses were well tolerated. These results are consistent with data from Caucasian populations.

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Background: Tree nut allergy is one of the common potentially life-threatening food allergies in children and adults. Recombinant food allergens offer new perspectives to solve problems of clinical and molecular allergology in diagnosis, research, and therapy of food allergies. So far, superoxide dismutase (s) has been identified as a panallergen and studied in different allergenic sources. Manganese Superoxide Dismutase (MnSOD) has also been reported in pistachio that may cause allergic reactions in atopic subjects. The aim of this study was to describe the cloning, expression, and purification of MnSOD from pistachio nut.
Methods: The pistachio MnSOD was cloned and expressed in E. coli BL21 (DE3) using a vector pET-32b (+). A recombinant protein was purified by metal precipitation. The protein immunoreactivity was evaluated using patients' IgE binding by means of ELISA and immunoblotting assays.
Results: The MnSOD gene from pistachio was successfully cloned and expressed in E. coli. The purified pistachio MnSOD was recognized by IgE in 10 (40%) out of the 25 sera tested. Our results also showed that this protein might trigger some cross-reactions toward IgE antibodies and thus could be considered as a panallergen.
Conclusions: For the first time recombinant manganese superoxide dismutase from nut source was expressed as a possible allergen. This pistachio allergen could be a possible basis for cross-reactivity with MnSOD from other sources.

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Background: Screening patients for latex allergy prior to surgery is an important but intensive procedure. The appropriate testing strategy for diagnosing latex (Hevea brasiliensis) allergy involves in-vitro specific IgE or skin prick testing. The sensitivity and specificity of both tests are influenced by patient-specific factors or manufacturing processes that alter the clinically relevant allergens in skin testing solutions.
Methods: Total IgE and latex-specific IgE testing was introduced as a screening test. Skin prick testing was done on patients with a high probability of latex allergy and negative specific IgE with total IgE <100kU/L. SDS-PAGE was done on the non-ammoniated latex (NAL) and newly introduced ammoniated latex (AL) reagents for the clinically relevant allergens.
Results: 51 patients had a total IgE <100 (range, 2.8-99.0kU/L), and 10% had a positive skin test. 60% of positive skin tests would have been missed with lower total IgE cut-offs of 50kU/L (6% of referrals). SDS-PAGE of the NAL solution showed 3 prominent bands with molecular weights of approximately 20, 24 and 42kDa that correlated with Hev b 6, Hev b 3 and Hev b 7/13, respectively. In contrast, the AL solution showed 3 very faint higher molecular weights bands that did not correlate with clinically relevant antigens.
Conclusions: Increasing the cut-off value of total IgE for allergen-specific IgE testing increased the sensitivity of the specific IgE test. The NAL reagent had a greater number of clinically significant allergens at higher concentrations than AL, which may have implications for the clinical sensitivity of the newer AL reagent.

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Background: Atopic and vernal keratoconjunctivitis are severe types of ocular allergic disease characterized not only by conjunctival inflammation but also by corneal involvement. In vitro studies have suggested that breakdown of corneal epithelial barrier function and subsequent activation of stromal fibroblasts may amplify ocular allergic inflammation.
Case Summary: A 27-year-old man with atopic dermatitis developed atopic keratoconjunctivitis including corneal ulcer with plaque deposition in his right eye. Conjunctival inflammation in the right eye was resistant to topical steroid therapy. Surgical removal of corneal plaque and administration of autologous fibronectin eyedrops resulted not only in resurfacing of the corneal epithelium but also in amelioration of conjunctival inflammation.
Discussion: This case suggests that loss of corneal epithelial integrity likely exacerbates conjunctival allergic inflammation and that restoration or maintenance of the barrier function of the corneal epithelium may be one of the important targets for the treatment of severe ocular allergic diseases.

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Background: Transforming growth factor-β (TGF-β) levels are elevated in the nasal mucosa in allergic rhinitis. However, because TGF-β is secreted extracellulary in latent complexes, it remains unclear whether the local TGF-β expression actually drives active signaling and affects the pathophysiology of allergic rhinitis. The objective of this study is to investigate whether TGF-β signaling is activated in allergic rhinitis and plays a role in the pathophysiology of allergic rhinitis.
Methods: An ovabumin (OVA)-sensitized and -nasally challenged mouse model of allergic rhinitis was established and phosphorylation of Smad2 in the nasal mucosa was examined by immunohistochemistry. In addition, the effects of the pharmacological inhibition of endogenous TGF-β signaling on the allergic rhinitis model were histologically examined. Furthermore, phosphorylation of Smad2 in the nasal mucosa samples obtained from patients with allergic rhinitis was also evaluated.
Results: In the mouse model of allergic rhinitis, OVA challenge induced phosphorylation of Smad2 predominantly in epithelial cells in the nasal mucosa. In addition, the administration of an inhibitor of TGF-β type I receptor kinase activity during OVA challenge suppressed goblet cell hyperplasia in the nasal mucosa. Furthermore, phosphorylated Smad2 expression increased in nasal epithelial cells in patients with allergic rhinitis.
Conclusions: These results suggest that TGF-β signaling is activated in epithelial cells in the nasal mucosa in allergic rhinitis and may contribute to the development of goblet cell hyperplasia.

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