Masao Yamaguchi

Japanese Guideline for Adult Asthma

Adult bronchial asthma (hereinafter, asthma) is characterized by chronic airway inflammation, reversible airway narrowing, and airway hyperresponsiveness. Long-standing asthma induces airway remodeling to cause an intractable asthma. The number of patients with asthma has increased, while the number of patients who die from asthma has decreased (1.7 per 100,000 patients in 2009). The aim of asthma treatment is to enable patients with asthma to lead a healthy life without any symptoms. A partnership between physicians and patients is indispensable for appropriate treatment. Long-term management with agents and elimination of causes and risk factors are fundamental to asthma treatment. Four steps in pharmacotherapy differentiate mild to intensive treatments; each step includes an appropriate daily dose of an inhaled corticosteroid (ICS), varying from low to high doses. Long-acting β(2) agonists (LABA), leukotriene receptor antagonists, and theophylline sustained-release preparation are recommended as concomitant drugs, while anti-IgE antibody therapy is a new choice for the most severe and persistent asthma. Inhaled β(2) agonists, aminophylline, corticosteroids, adrenaline, oxygen therapy, etc., are used as needed against acute exacerbations. Allergic rhinitis, chronic obstructive pulmonary disease (COPD), aspirin induced asthma, pregnancy, and cough variant asthma are also important factors that need to be considered.

Leptin Enhances Survival and Induces Migration, Degranulation, and Cytokine Synthesis of Human Basophils

Basophils are the rarest leukocytes in human blood, but they are now recognized as one of the most important immunomodulatory as well as effector cells in allergic inflammation. Leptin, a member of the IL-6 cytokine family, has metabolic effects as an adipokine, and it is also known to participate in the pathogenesis of inflammatory reactions. Because there is an epidemiologic relationship between obesity and allergy, we examined whether basophil functions are modified by leptin. We found that human basophils express leptin receptor (LepR) at both the mRNA and surface protein levels, which were upregulated by IL-33. Leptin exerted strong effects on multiple basophil functions. It induced a strong migratory response in human basophils, similar in potency to that of basophil-active chemokines. Also, leptin enhanced survival of human basophils, although its potency was less than that of IL-3. Additionally, CD63, a basophil activation marker expressed on the cell surface, was upregulated by leptin, an effect that was neutralized by blocking of LepR. Assessments of basophil degranulation and cytokine synthesis found that leptin showed a strong priming effect on human basophil degranulation in response to FcεRI aggregation and induced Th2, but not Th1, cytokine production by the cells. In summary, the present findings indicate that leptin may be a key molecule mediating the effects of adipocytes on inflammatory cells such as basophils by binding to LepR and activating the cellular functions, presumably exacerbating allergic inflammation.

Japanese Guideline for Adult Asthma 2014.

Adult bronchial asthma (hereinafter, asthma) is characterized by chronic airway inflammation, reversible airway narrowing, and airway hyperresponsiveness. Long-standing asthma induces airway remodeling to cause intractable asthma. The number of patients with asthma has increased, and that of patients who die from asthma has decreased (1.5 per 100,000 patients in 2012). The aim of asthma treatment is to enable patients with asthma to lead a normal life without any symptoms. A good relationship between physicians and patients is indispensable for appropriate treatment. Long-term management with antiasthmatic agents and elimination of the causes and risk factors of asthma are fundamental to its treatment. Four steps in pharmacotherapy differentiate between mild and intensive treatments; each step includes an appropriate daily dose of an inhaled corticosteroid, varying from low to high. Long-acting 02-agonists, leukotriene receptor antagonists, and sustained-release theophylline are recommended as concomitant drugs, while anti-immunoglobulin E antibody therapy has been recently developed for the most severe and persistent asthma involving allergic reactions. Inhaled 02-agonists, aminophylline, corticosteroids, adrenaline, oxygen therapy, and others are used as needed in acute exacerbations by choosing treatment steps for asthma exacerbations depending on the severity of attacks. Allergic rhinitis, chronic obstructive pulmonary disease, aspirin-induced asthma, pregnancy, asthma in athletes, and coughvariant asthma are also important issues that need to be considered.

Japanese guidelines for adult asthma 2017

Adult bronchial asthma is characterized by chronic airway inflammation, and presents clinically with variable airway narrowing (wheezes and dyspnea) and cough. Long-standing asthma induces airway remodeling, leading to intractable asthma. The number of patients with asthma has increased; however, the number of patients who die of asthma has decreased (1.2 per 100,000 patients in 2015). The goal of asthma treatment is to enable patients with asthma to attain normal pulmonary function and lead a normal life, without any symptoms. A good relationship between physicians and patients is indispensable for appropriate treatment. Long-term management by therapeutic agents and elimination of the causes and risk factors of asthma are fundamental to its treatment. Four steps in pharmacotherapy differentiate between mild and intensive treatments; each step includes an appropriate daily dose of an inhaled corticosteroid, varying from low to high levels. Long-acting β2-agonists, leukotriene receptor antagonists, sustained-release theophylline, and long-acting muscarinic antagonist are recommended as add-on drugs, while anti-immunoglobulin E antibody and oral steroids are considered for the most severe and persistent asthma related to allergic reactions. Bronchial thermoplasty has recently been developed for severe, persistent asthma, but its long-term efficacy is not known. Inhaled β2-agonists, aminophylline, corticosteroids, adrenaline, oxygen therapy, and other approaches are used as needed during acute exacerbations, by choosing treatment steps for asthma in accordance with the severity of exacerbations. Allergic rhinitis, eosinophilic chronic rhinosinusitis, eosinophilic otitis, chronic obstructive pulmonary disease, aspirin-induced asthma, and pregnancy are also important issues that need to be considered in asthma therapy.

Bitter Sweet: A Child Case of Erythritol-Induced Anaphylaxis

The prevalence of anaphylaxis induced by food has increased in recent years. Identifying the offending food in each case of anaphylaxis is critical for prevention of recurrence, but this is sometimes difficult since the causes are not only well-known allergens such as peanuts but sometimes rare, unexpected allergens such as oligosaccharides.1 Here, we report an 11-year-old boy who experienced anaphylaxis upon ingesting an erythritol-containing food. Erythritol is a sugar alcohol that is commonly used as a sweetener in the modern diet. An 11-year-old boy was admitted to our hospital because of anaphylaxis. At the age of 7, he began to experience episodes of urticaria and wheezing after ingesting foods. He had bronchial asthma and allergic conjunctivitis, but no family history of allergies. Based on his history and positive tests for IgE specific for wheat and peanuts at the initial examination, his physician instructed him to avoid eating foods containing wheat and peanuts. Despite elimination of those foods, he was hospitalized because of anaphylaxis after ingesting a diet sauce when he was 10. At the age of 11, he again experienced severe wheezing and generalized urticaria after eating a health-food made from grapefruit. The main raw material in that health food was grapefruit, but he never experienced symptoms after eating fresh grapefruit. We searched for a common ingredient in the diet sauce and the health food, and suspected erythritol as the possible cause of his anaphylaxis. We performed the following examinations to identify the offending allergen. First, a double-blind placebo-controlled food challenge (DBPCFC) was performed using a sweetener containing erythritol and small amounts of acesulfame potassium and sucralose. We used granulated sugar (sucrose fructose glucose) as a control by adjusting the doses to have a similar degree of sweetness. He developed cutaneous pruritus followed by wheezing, dyspnea and generalized urticaria immediately after ingestion of the erythritol-containing sweetener, but not after ingestion of granulated sugar. He was treated with inhalation of oxygen and nebulized salbutamol, intramuscular epinephrine, and intravenous chlorpheniramine and methylpredonisolone. Second, a skin-prick test was performed using two commercially available erythritol-containing sweeteners. Both sweeteners induced wheals having half the diameter of that induced by histamine. No reactions were observed in two healthy adult controls. We then performed a scratch test using pure erythritol solutions at 2 mg mL, 20 mg mL and 200 mg mL in distilled water. The patient showed positive reactions to erythritol in a concentration-dependent manner. The healthy controls showed no reactions. To further confirm the allergic reaction to erythritol in vitro, we performed a basophil activation test (BAT) for CD203 c expression. A commercial kit (Allergenicity kit, Beckman Coulter, Fullerton, CA, USA) was used for quantification of basophil CD203c expression as previously described2 with erythritol, PalsweetR (an aspartame erythritolcontaining sweetener), sucrose and granulated sugar (sucrose fructose glucose) at the indicated concentrations. Erythritol and PalsweetR induced markedly enhanced expression of CD203c on basophils from the patient, not those from two healthy adult controls (Fig. 1A and B). Neither the patient nor the controls showed any response to sucrose or granulated sugar (Fig. 1C and D). The results indicate that erythritol directly induced basophil activation in the patient. We diagnosed the patient’s reaction as erythritol allergy and instructed the patient to avoid erythritolcontaining foods. There have been some reports of allergic reactions to aspartame3,4 and other food additives.5 Erythritol allergy, especially in children, is very rare. To the best of our knowledge, only adult cases have been reported, 6,7 making the present patient the first reported pediatric case. In the reports of adult patients, the diagnosis was based on the clinical symptoms and skin tests with no confirmatory FC. We confirmed the diagnosis by DBPCFC, with additional evidence from such as BAT and skin tests. Erythritol is a natural sugar alcohol that is a product of fermentation of glucose. It is contained in natural foods such as fruits (e.g., pears and grapes) and mushrooms, and in fermented foods such as soy sauce and bean paste. The use of erythritol as a sweetener in Japan started in 1990 and Japanese consumption is currently around 6000 tons per year. When ingested, it is absorbed by the small intestine and then transferred to the blood. Erythritol is not metabolized, and more than 90% of ingested erythritol is excreted in the urine, thereby making it almost calorie-free. Although erythritol is regarded as highly safe and not carious, the present case suggests that it could be harmful if a patient develops hypersensitivity to the molecule. However, we were unable to identify a specific IgE antibody to erythritol. We did not detect IgE binding to erythritol in an ELISA system. We suspected that the negative result was due to the technical difficulty of immobilizing a sufficient amount of erythritol to the assay plate. We also did not find erythritolinduced basophil histamine release in passive sensitization experiments using serum from the patients and the methods reported elsewhere.8 These negaAllergology International. 2013;62:269-271

Leptin enhances ICAM-1 expression, induces migration and cytokine synthesis, and prolongs survival of human airway epithelial cells.

There is rising interest in how obesity affects respiratory diseases, since epidemiological findings indicate a strong relationship between the two conditions. Leptin is a potent adipokine produced mainly by adipocytes. It regulates energy storage and expenditure and also induces inflammation. Previous studies have shown that leptin is able to activate inflammatory cells such as lymphocytes and granulocytes, but little is known about its effect on lung structural cells. The present study investigated the effects of leptin on human airway epithelial cells by using human primary airway epithelial cells and a human airway epithelial cell line, BEAS-2B. Flow cytometry showed enhanced ICAM-1 expression by both of those cells in response to leptin, and that effect was abrogated by dexamethasone or NF-κB inhibitor. Flow cytometry and quantitative PCR showed that airway epithelial cells expressed leptin receptor (Ob-R), whose expression level was downregulated by leptin itself. Multiplex cytokine analysis demonstrated enhanced production of CCL11, G-CSF, VEGF, and IL-6 by BEAS-2B cells stimulated with leptin. Furthermore, transfection of Ob-R small interference RNA decreased the effect of leptin on CCL11 production as assessed by quantitative PCR. Finally, leptin induced migration of primary airway epithelial cells toward leptin, suppressed BEAS-2B apoptosis induced with TNF-α and IFN-γ, and enhanced proliferation of primary airway epithelial cells. In summary, leptin was able to directly activate human airway epithelial cells by binding to Ob-R and by NF-κB activation, resulting in upregulation of ICAM-1 expression, induction of CCL11, VEGF, G-CSF, and IL-6 synthesis, induction of migration, inhibition of apoptosis, and enhancement of proliferation.

A Case of Anaphylactic Reaction Following Matsutake Mushroom Ingestion: Demonstration of Histamine Release Reaction of Basophils

BACKGROUNDnMatsutake mushroom is not recognized as a common food allergen. However, several case reports have suggested that this mushroom can induce anaphylaxis on rare occasions.nnnCASE SUMMARYnWe report a woman with bronchial asthma, who experienced two episodes of Matsutake-induced anaphylaxis. Both the prick-to-prick test and basophil histamine release test showed positive reactions to this mushroom in this patient, but not in control subjects.nnnDISCUSSIONnMatsutake mushroom can, on rare occasions, cause anaphylaxis in sensitized people, a reaction so far observed only in Japan. Not ony the in vivo prick-to-prick test but also the in vitro basophil activation test utilizing the patients blood represent useful methods for allergen identification and also for identification of sensitized subjects.

The in vitro Effects of Advanced Glycation End Products on Basophil Functions

Background: Basophils are thought to play pivotal roles in the pathogenesis of allergic reactions, but their roles in inflammation associated with systemic abnormalities such as metabolic disorders remain largely unknown. Advanced glycation end products (AGEs) are potentially important substances produced in high-glucose disease conditions. In this in vitro study, we investigated whether the biological functions of human basophils can be influenced by AGEs. Methods: We analyzed the effects of AGEs on various functions and markers of human basophils, including CD11b expression, apoptosis, degranulation, and cytokine production. Results: Flow cytometric analysis indicated that the level of the receptor for AGEs (RAGE) on the surface of freshly isolated basophils was very low but was clearly upregulated by IL-3. Apoptosis of basophils was induced by high concentrations of glycated albumin. Although glycated albumin failed to affect the level of surface CD11b expression or to trigger degranulation or production of IL-4 and IL-13 in basophils, it dose-dependently induced IL-6 and IL-8 secretion. Conclusions: AGEs seem to act on human basophils; they suppress the cells’ longevity but elicit secretion of inflammatory cytokines. Through these biological changes, basophils might play some roles in inflammatory conditions associated with metabolic disorders presenting elevated levels of AGEs.

Concerted expression of eotaxin-1, eotaxin-2, and eotaxin-3 in human bronchial epithelial cells *

Eotaxin-1/CCL11, eotaxin-2/CCL24, and eotaxin-3/CCL26 bind specifically and exclusively to CC chemokine receptor (CCR) 3, which is a potential therapeutic target in treating the peribronchial eosinophilia associated with allergic airway diseases. Bronchial epithelial cells represent an important source of chemokines, and thus we investigated in vitro and in vivo expression of eotaxin-2 and eotaxin-3 in bronchial epithelial cells in comparison with that of eotaxin-1. Immunohistochemistry showed increased expression of both eotaxin-2 and eotaxin-3 in addition to eotaxin-1 in asthmatics. Considerable amounts of eotaxins were secreted by bronchial epithelial lineage. As with eotaxin-1 production, generation of eotaxin-2 and eotaxin-3 by bronchial epithelial cells was up-regulated by IL-4 and IL-13, and attenuated by IFN-gamma and glucocorticoids. In addition to eotaxin-1 expression, but also eotaxin-2 and eotaxin-3 expression in the bronchial epithelium should be taken into consideration when developing the therapeutic strategies to treat eosinophilic airway diseases.

The basophil activation test identified carminic acid as an allergen inducing anaphylaxis

T0 THE EDITOR: In the autumn of 2011, a 39-year-old Japanese woman was referred for evaluation of allergic reactions after ingestion of a commercial bottled supplement that contained vitamin Bs and C and fruit flavors. The reactions occurred 3 times, at 1-month intervals. The first 2 episodes were mild and consisted of an itchy throat and localized hives on her lower extremities. However, after drinking the aforementioned supplement every day for 3 months, she manifested more severe symptoms of anaphylactic shock, with an itchy throat, generalized urticaria, diarrhea, and low blood pressure. Interestingly, each of the allergic reactions was associated with her menstrual period; the episodes occurred within 3 days before or after the beginning day of menstruation. Skin prick tests were negative for the supplement. An intradermal test showed that a 10-fold dilution of the solution was an irritating concentration that elicited reactions in the patient and all 4 of the tested controls; lower, nonirritating concentrations showed negative intradermal results. We then tried the in vitro basophil activation test (BAT), which analyzes surface activation marker CD203c expression on basophils. Importantly, the drink itself and, among its constituents, only cochineal dye gave clearly positive results in BAT with the use of the patient’s blood, but not nonallergic subjects’ blood. BAT was highly sensitive and selective, because obvious induction of basophil surface CD203c was observed with 10to 640-fold dilutions of the supplement, the corresponding dose of cochineal dye and its main constituent, carminic acid (purity 97%), but not with a protein extracted from Coccus cacti (Figure 1). In vitro sensitization experiments showed that carminic acideinduced basophil activation was IgE-mediated, because passive sensitization of a normal donor’s basophils by the patient’s serum was completely blocked by the presence of an antiIgE antibody, omalizumab (Figure 2). On the basis of these results, the patient was strongly discouraged from consuming drinks and foods that contained cochineal dye. She has subsequently experienced no further anaphylactic episodes. Although confirmatory challenge was unable to be performed to prove causation because the patient refused to undergo this test, on the basis of her BAT and the absence of anaphylaxis when she avoided carminic acid, we believe that carminic acid, in association with her menstrual cycle, was responsible for her anaphylaxis. Cochineal dye is usually regarded as a highly safe material, and it is widely used as a food additive and cosmetic ingredient. To date, type I allergy due to the dye, including anaphylaxis, urticarial, and occupational asthma, has been reported only occasionally. Allergy to cochineal dye is generally because of a hypersensitivity reaction to a contaminating protein (ie, CC38K, a phospholipase), whereas allergy to the main compound, carminic acid, is rare. Carminic acid is a relatively small molecule (molecular weight 492) that is thought to exhibit allergenicity as a protein-bound hapten. Although skin tests are usually sensitive and useful for allergen determination, they sometimes cause nonspecific skin stimulation. This limits the reliability of the tests, as in our present patient. Here, we were impressed by the finding that BAT accurately identified the allergen. That is, the test clearly showed that the patient’s own basophils, but not those of nonallergic donors, responded to highly pure carminic acid but not to a protein extracted from Coccus cacti. Furthermore, the patient’s basophils showed an obvious response to the allergen in BAT during menstruation, compared with the rest of the menstrual cycle (Figure 1, E); this result was in clear contrast to the absence of any menstruation-related enhancement of a response to polyclonal anti-IgE antibody. On the basis of these results, we believe that an in vitro BAT with the use of peripheral blood would be highly useful for analyzing cochineal dye-induced allergy. At present, we do not know the exact mechanism(s) underlying menstruation-associated changes in the basophil response; overnight culture of our patient’s cells with estradiol or progesterone at 1 mmol/L failed to modulate the response to carminic acid. Recent progress in the pathogenesis of allergies has strongly implicated not only mast cells but also basophils as being critically involved in several allergic responses. Flow cytometric assessment of surface markers, including CD203c, has enabled precise determination of the activation status of basophils. In regard to carminic acid-related allergy, our present results suggest that basophils are highly sensitive to this allergen and that the cells might behave as a key initiator/effector in vivo. Thus, future analyses of the basophil activation status during clinical anaphylaxis will be important for elucidating the involvement of this cell type in this allergic reaction.