Long-term sublingual immunotherapy provides better effects for patients with Japanese cedar pollinosis.

OBJECTIVE: Japanese cedar pollinosis is an endemic disease affecting a large proportion of Japan's population. Five seasons have passed since sublingual immunotherapy (SLIT) for Japanese cedar pollinosis was included in the public insurance coverage in Japan. In this study, we evaluated the clinical effects of long-term SLIT for Japanese cedar pollinosis on upper respiratory symptoms primarily represented by nasal symptoms and inflammation of the respiratory tract in the 2019 season, in which considerable amount of cedar pollen was dispersed. METHODS: This study involved 95 patients who were undergoing SLIT for Japanese cedar pollinosis after the initiation at some point between 2014 and 2018, and this group of patients was compared with a control group comprising 21 patients receiving preseasonal prophylactic treatment (with a second-generation antihistaminic drug). We evaluated the patients' nasal/eye symptoms, total nasal symptom and medication score (TNSMS), and quality of life according to relevant guidelines. In addition, the levels of peripheral blood eosinophils, serum total IgE, Japanese cedar antigen-specific IgE, Cryj1-specific IgG4, and fractional exhaled nitric oxide (FENO) were measured as objective indices. RESULTS: From the fourth season (SLIT4), nasal discharge, sneezing, nasal obstruction symptoms, and TNSMS significantly decreased compared with those in the preseasonal prophylactic treatment and SLIT1 groups. In the patients suspected to have eosinophilic airway inflammation (with a baseline FENO ≥25 ppb), the interannual variability of FENO levels significantly reduced after 5 years of treatment. CONCLUSION: The efficacy of SLIT was noted from the first year of treatment, even in a year when pollen profusely dispersed. Thus, long-term continuous treatment with SLIT may alleviate nasal symptoms as well as eosinophilic airway inflammation.

Effects of sublingual immunotherapy on nasal symptoms and sleep disturbance in patients with Japanese cedar pollinosis.

OBJECTIVE: Japanese cedar (JC) pollinosis is the most common seasonal allergic rhinitis (AR) in Japan. AR reduces the quality of life not only because of nasal symptoms but also because of sleep disturbance. In the present study, we investigated the effects of sublingual immunotherapy (SLIT) with a standardized JC pollen extract on nasal symptoms and AR-related sleep disturbance in patients with JC pollinosis. METHODS: In the present non-randomized controlled study, we assigned thirty-one patients with JC pollinosis who received SLIT into the SLIT group, and another thirty-eight patients with JC pollinosis who visited our hospital without treatment into the untreated group. We evaluated nasal symptoms and sleep disturbance using the classification of the severity of AR symptoms and the Athens Insomnia Scale, respectively. RESULTS: The nasal symptom scores and the Athens Insomnia Scale scores of patients in the SLIT group were both significantly lower than those of patients in the untreated group. There was a significant correlation between total nasal symptom scores and the Athens Insomnia Scale scores. CONCLUSIONS: These findings suggested that SLIT with JC pollen extract suppressed nasal symptoms in patients with JC pollinosis, leading to improvements in AR-related sleep disturbance and daytime troubles with daily life.

Latent 1,3-ß-D-glucan acts as an adjuvant for allergen-specific IgE production induced by Japanese cedar pollen exposure.

BACKGROUND: The pollen grains of several plant species contain 1,3-ß-D-glucan (BG). BG activates dendritic cells (DCs) and subsequently regulates the innate immune responses. Within Japan, the most common disease associated with type-I hypersensitivity is Japanese cedar pollinosis. However, the role of BG in Japanese cedar pollen (JCP) remains unclear. This study examined the localization and immunological effects of BG in JCP. METHODS: The localization of BG in JCP grain was determined by immunohistochemical staining using a soluble dectin-1 protein probe and a BG recognition protein (BGRP). The content of BG extracted from JCP was measured by a BGRP-based ELISA-like assay. The cytokine production by bone marrow-derived DCs (BMDCs) obtained from wild-type and BG receptor (dectin-1) knock-out mice was examined in vitro. The mice were intranasally administered JCP grains and the specific serum Ig levels were then quantified. RESULTS: BG was detected in the exine and cell wall of the generative cell and tube cell of the JCP grain. Moreover, BG in the exine stimulated production of TNF-α and IL-6 in the BMDCs via a dectin-1-dependent mechanism. Meanwhile, JCP-specific IgE and IgG were detected in the serum of wild-type mice that had been intranasally administered with JCP grains. These mice also exhibited significantly enhanced sneezing behavior. However, dectin-1 knock-out mice exhibited significantly lower JCP-specific IgE and IgG levels compared to wild-type mice. CONCLUSIONS: Latent BG in JCP can act as an adjuvant to induce JCP-specific antibody production via dectin-1.

Comparison of sensitization and prevalence of Japanese cedar pollen and mite-induced perennial allergic rhinitis between 2006 and 2016 in hospital workers in Japan.

BACKGROUND: The prevalence of allergic rhinitis (AR) is increasing worldwide, mainly due to an increase in antigen exposure. We conducted an epidemiological study involving the staff of the University of Fukui Hospital and its associated hospital in 2006. There were 1540 participants aged ≥20 years, and the rates of Japanese cedar (JC) pollinosis and mite-induced perennial allergic rhinitis (PAR) were 36.8% and 15.8%, respectively. In 2016, we conducted a second survey. METHODS: The rate of sensitization to JC pollen and mites and the prevalence of JC pollinosis and mite-induced PAR were analyzed based on data from questionnaires and antigen-specific immunoglobulin E (IgE) levels. RESULTS: In the present study, we analyzed data of 1472 participants aged between 20 and 59 years. Total sensitization to JC pollen and total prevalence of JC pollinosis were 57.8% (851/1472) and 40.8% (601/1472), respectively. Total sensitization to mites and total prevalence of mite-induced PAR were 41.4% (610/1472) and 18.8% (276/1472), respectively. Total prevalence of JC pollinosis and mite-induced PAR increased significantly over a decade. Among the 334 people who participated in the 2006 and 2016 cross-sectional studies, 13% of JC pollinosis and 36% of mite-induced PAR experienced remission. However, since the number of new onset cases was higher that the number of remission cases, a slight increase in prevalence was observed over a decade. CONCLUSIONS: The prevalence of JC pollinosis and mite-induced PAR continues to show increasing trends, accompanied by an increase in antigen exposure. The remission rate of JC pollinosis was particularly low.

Long-term treatment of Japanese cedar pollinosis with Japanese cedar pollen SLIT drops and persistence of treatment effect: A post-marketing clinical trial.

BACKGROUND: There have been no reports of treatment effect persistence after long-term sublingual immunotherapy (SLIT) in patients with Japanese cedar (JC) pollinosis. Therefore, we conducted a post-marketing clinical trial to investigate the efficacy, safety, and effect persistence of JC pollen SLIT drops after approximately 3 years of treatment. METHODS: This was an open-label trial of 233 patients with JC pollinosis who were treated with JC pollen SLIT drops for approximately 3 years (2015-2017) and followed-up for an additional 2 years (2018-2019). Efficacy and effect persistence were evaluated using nasal and ocular symptom scores, daily use of rescue medication, and Japanese Rhinoconjunctivitis Quality of Life Questionnaire scores recorded during the JC pollen dispersal season of each year. Safety was evaluated by monitoring adverse events and adverse drug reactions. RESULTS: The mean combined total nasal symptom and medication score (range 0-18) during the peak symptom periods of 2015 through 2019 were 5.47 ± 3.38, 4.52 ± 3.13, 3.58 ± 2.63, 5.28 ± 4.01, and 6.83 ± 4.65, respectively. The percentage of patients who used no rescue medications during the same periods was 64.8%, 75.2%, 80.3%, 63.7%, and 50.3%, respectively. A total of 138 adverse drug reaction incidents were recorded in 73 of the 233 patients (31.3%), of which 134 incidents (97.1%) were mild in severity. CONCLUSIONS: JC pollen SLIT drops demonstrated treatment duration-dependent efficacy with effects that persisted for 2 years after cessation of treatment. The drug had a favorable safety profile over the 5-year study period.

Preliminary Clinical Trial of Biomarkers to Predict Response to Sublingual Immunotherapy for Japanese Cedar Pollinosis.

BACKGROUND: As part of the planning for a future multicenter study, this preliminary clinical trial used serum samples from patients to identify biomarkers for predicting the therapeutic effects of sublingual immunotherapy (SLIT) for Japanese cedar pollinosis (JCP). METHODS: This prospective study included patients undergoing SLIT for JCP at our hospital. All enrolled patients (N = 17) started SLIT between June and November of 2015. With informed consent from the patients, blood samples were obtained in January, March, and June of 2016, and patients completed the Japan rhino-conjunctivitis quality of life questionnaire (JRQLQ). On the basis of the JRQLQ results, the 6 patients with the best outcomes were included in the high-response group (HRG), and the 5 patients with the worst outcomes were included in the poor-response group (PRG). We then compared serum data between the two groups, to identify useful biomarkers. RESULTS: IL-12p70 and VEGF levels tended to be higher in the HRG than in the PRG in January, March, and June (0.10 > p > 0.05). In addition, the June IL-17 level was significantly higher (p < 0.05) in the HRG than in the PRG. CONCLUSIONS: IL-12p70 and VEGF may be useful biomarkers for predicting the effects of SLIT. In addition, although IL-17 does not appear to be useful as a biomarker for evaluating treatment response at the start of SLIT, it may be useful as a biomarker after the beginning phase of SLIT.

Treatment duration-dependent efficacy of Japanese cedar pollen sublingual immunotherapy: Evaluation of a phase II/III trial over three pollen dispersal seasons.

BACKGROUND: We conducted a randomized, placebo-controlled, double-blind clinical trial to investigate the optimal dose and long-term efficacy and safety of Japanese cedar (JC) pollen tablets for SLIT (JapicCTI-142579). Here, we report details of the effects of the JC pollen SLIT tablet on rhinitis and conjunctivitis symptoms over three pollen dispersal seasons. METHODS: A total of 1042 JC pollinosis patients (aged 5-64 years) were randomized to receive tablets containing placebo (P), 2000, 5000, or 10,000 Japanese allergy units (JAU) of JC pollen for 15 months to identify an optimal dose. Patients receiving P (n = 240) and the optimal dose (5000 JAU; A, n = 236) were then randomized to receive P or A for an additional 18 months (AA, AP, PA, and PP groups, allocation ratio 2:1:1:2). Nasal and ocular symptoms, rescue medication use, and quality of life (QOL) were assessed on quantitative scales. RESULTS: In the second and third seasons, the AA, AP, and PA groups exhibited significantly better improvements in nasal, ocular, and medication scores compared with the PP group in the order AA > AP > PA > PP during the second season and AA > PA > AP > PP during the third season. Rescue medication use and QOL scores were also significantly better in the AA, AP, and PA groups compared with the PP group. CONCLUSIONS: The JC pollen SLIT tablet relieved nasal and ocular symptoms and medication use and improved QOL in a treatment duration-dependent manner. Continuous dosing regimens appear to enhance the efficacy of the drug.

An Electrostatic-Barrier-Forming Window that Captures Airborne Pollen Grains to Prevent Pollinosis.

An electrostatic-barrier-forming window (EBW) was devised to capture airborne pollen, which can cause allergic pollinosis. The EBW consisted of three layers of insulated conductor wires (ICWs) and two voltage generators that supplied negative charges to the two outer ICW layers and a positive charge to the middle ICW layer. The ICWs generated an attractive force that captured pollen of the Japanese cedar, Cryptomeria japonica, from air blown through the EBW. The attractive force was directly proportional to the applied voltage. At ≥3.5 kV, the EBW exerted sufficient force to capture all pollen carried at an air flow of 3 m/s, and pollen-free air passed through the EBW. The findings demonstrated that the electrostatic barrier that formed inside the EBW was very effective at capturing airborne pollen; thus, it could allow a home to remain pollen-free and healthy despite continuous pollen exposure.

Immunodominance in allergic T-cell reactivity to Japanese cedar in different geographic cohorts.

BACKGROUND: Japanese cedar (JC) pollen is a common trigger for allergic rhinitis in Japan. Pollen proteins targeted by IgE, including Cry j 1 and Cry j 2, and isoflavone reductase (IFR) have been identified. OBJECTIVE: To compare antigen-specific IgE titers and T-cell responses to JC pollen-derived extract and peptides in cohorts with high and low pollen exposure. METHODS: Peripheral blood mononuclear cells from JC pollen allergic or nonallergic patients who have lived in Japan for at least 1 year and JC pollen allergic patients who have never been to Japan were tested for T-cell responses against JC pollen extract and peptide pools derived from Cry j 1, Cry j 2, or IFR. T-cell reactivity was assessed by interleukin 5 and interferon γ production by ELISPOT. RESULTS: JC pollen-specific T-cell reactivity and IgE titers were significantly higher in the allergic compared with the nonallergic Japanese cohort, which was also associated with different patterns of polysensitization. Interestingly, a significant overlap was observed in the hierarchy of the T-cell epitopes in the allergic Japanese cohort compared with the allergic non-Japanese cohort. In all 3 cohorts, T-cell reactivity was dominantly directed against peptides from the major allergens Cry j 1 and 2, with few T-cell responses detected against IFR. CONCLUSION: Our studies identify common denominators of T-cell reactivity in patient populations with different sensitization patterns, suggesting that generally applicable immunotherapeutic approaches might be developed irrespective of exposure modality.

Effect of intranasal corticosteroid on pre-onset activation of eosinophils and mast cells in experimental Japanese cedar pollinosis.

BACKGROUND: Minimal persistent inflammation (MPI) contributes to hyperreactivity in allergic rhinitis. However, little is known regarding whether pre-onset activation of eosinophils and mast cells is present or not in Japanese cedar pollinosis (JCP). Furthermore, a prophylactic effect of intranasal corticosteroids on such MPI in JCP has not been investigated. METHODS: We designed a double-blinded, randomized, placebo-controlled, crossover trial. Twenty patients with JCP were examined outside the pollen season (UMIN000008410). Nasal provocation with paper discs containing extracts of Japanese cedar pollen was performed once a day for 3 consecutive days. Onset of nasal symptoms was monitored over 15 min after each provocation. The levels of eosinophil cationic protein (ECP) and tryptase in nasal secretions were examined. Fluticasone furoate nasal spray or placebo treatment was started one day before the first provocation. RESULTS: In the placebo group, 25% of the patients showed onset of nasal symptoms following provocation on the first day. In addition, 75% and 68% of the patients showed symptom onset on the second and third day of provocation, respectively. After the first provocation, the levels of ECP and tryptase in nasal secretions were significantly increased. These increases were seen not only in symptomatic but also in asymptomatic subjects in response to provocation, and the levels were similar between these subjects. Prophylactic treatment with fluticasone significantly suppressed the increase in nasal ECP and tryptase associated with repeated provocations. CONCLUSIONS: These results suggest that pre-onset activation of eosinophils and mast cells is present in experimental JCP, and that prophylactic treatment with intranasal corticosteroids has the potential to control such activation.

Spectrum of allergens for Japanese cedar pollinosis and impact of component-resolved diagnosis on allergen-specific immunotherapy.

The high prevalence of Japanese cedar pollinosis in Japan is associated with a negative impact on the quality of life of patients, as well as significant loss of productivity among the workforce in early spring, thus representing a serious social problem. Furthermore, the prevalence is increasing, and has risen by more than 10% in this decade. Cry j 1 and Cry j 2 were identified as the major allergens in Japanese cedar pollen (JCP), and in 2004, the existence of other major and minor allergens were revealed by a combination of two-dimensional electrophoresis and immunoblotting analysis. Allergenome analysis identified a chitinase, a lipid transfer protein, a serine protease, and an aspartic protease as novel IgE-reactive allergens in patients with JCP allergy. Thaumatin-like protein (Cry j 3) was shown to be homologous to Jun a 3, a major allergen from mountain cedar pollen. Isoflavone reductase-like protein was also characterized in a study of a JCP cDNA library. The characterization of component allergens is required to clarify the sensitizer or cross-reactive elicitor allergens for component-resolved diagnosis (CRD). Increasing evidence from numerous clinical trials indicates that CRD can be used to design effective allergen-specific immunotherapy. In this review, we summarize the eight characterized JCP allergens and discuss the impact of CRD and characterization of novel allergens on allergen-specific immunotherapy.

Patterns of Sensitization to Inhalant Allergens in Japanese Lower-Grade Schoolchildren and Related Factors.

OBJECTIVE: This study clarified sensitization patterns to house dust mite (HDM) and Japanese cedar pollen (JCP) in Japanese lower-grade schoolchildren. We also explored factors associated with allergic sensitization. METHODS: This cross-sectional study used a database from the Study on Respiratory Disease and Automobile Exhaust (SORA), a Japanese health study project. The subjects comprised 8,815 pupils aged 6-9 years. We obtained the distribution of HDM- and JCP-specific IgE, respectively, as a marker of sensitization. To determine factors associated with sensitization, we used logistic regression and calculated adjusted odds ratios (AORs) for the relative prevalence of sensitization. The cut-off point for specific IgE levels was 0.35 kU/l. RESULTS: Sensitization to HDM and JCP was detected in 51 and 39% of subjects, respectively, occurring more often in boys and at older ages. In addition, AORs of sensitization to HDM/JCP were higher in subjects with a history of bronchitis, parental asthma, parental atopic eczema and parental pollinosis. In contrast, AORs for sensitization were lower in those subjected to maternal passive smoking as well as among boys with pets. AORs of sensitization to JCP alone were lower in those with a history of otitis media, those who had been bottle milk fed, and those who were not the firstborn and who lived near a busy road. CONCLUSION: Sensitization to HDM and JCP was detected in 51 and 39% of lower-grade schoolchildren, respectively.

Continuous 6-year follow-up study of sensitization to Japanese cedar pollen and onset in schoolchildren.

BACKGROUND: Intra individual longitudinal data has been lacking for IgE-mediated seasonal allergic rhinitis (SAR), especially in young children. Little is known about the development and natural course of SAR in terms of prevalence and incidence rates in schoolchildren. METHODS: In May or June each year from 1994 to 2007, schoolchildren were assessed for serum Japanese cedar pollen (JCP)-IgE and house dust mite (HDM)-IgE levels, and surveyed regarding nasal symptoms. RESULTS: Among the 220 children initially assessed in the first grade, 69 (31.4%) were already sensitized to JCP at first grade and 119 (54.1%) did not develop JCP sensitivity during the 6-year study at all. In the first grade children who were HDM-sensitized but JCP non-sensitized, JCP-IgE level was significantly elevated compared to the JCP and HDM non-sensitized group. This seems to indicate that HDM sensitization was very strongly associated with JCP sensitization. CONCLUSIONS: Elevated serum IgE is a consequence of specific sensitization to HDM and HDM sensitization appeared to develop prior to the start of primary school which distinguishes HDM sensitization from JCP sensitization.

'Benifuuki' green tea containing o-methylated catechin reduces symptoms of Japanese cedar pollinosis: a randomized, double-blind, placebo-controlled trial.

BACKGROUND: Methylated catechin, one of the active ingredients in green tea, has been reported to ameliorate allergic reactions. We evaluated the efficacy of 'Benifuuki' green tea, which contains O-methylated epigallocatechin-3-O-[3-O-methyl] gallate (O-methylated EGCG), in alleviating Japanese cedar pollinosis (JCP). METHODS: The study was a double-blind, randomized, placebo-controlled trial. The subjects with JCP were randomly assigned to drink 700ml of 'Benifuuki' green tea containing O-methylated EGCG or 'Yabukita' green tea (not containing O-methylated EGCG) as a placebo every day from December 2007 through March 2008, which includes the pollen season. The primary outcome was the area under the curve (AUC) of symptom scores during the peak pollen season. RESULTS: Fifty-one adults with JCP participated in the study. Twenty-six subjects were assigned to 'Benifuuki' and 25 to 'Yabukita'. The AUC of symptom score during the peak pollen season in the 'Benifuuki' group was significantly smaller than in the 'Yabukita' group for each of runny nose, itchy eyes, tearing, total nasal symptom score, total ocular symptom score, nasal symptom-medication score and ocular symptom-medication score. The total QOL-related questionnaire score for one week in the peak pollen season was significantly better in the 'Benifuuki' group. Increase in the peripheral eosinophil count in response to pollen exposure was suppressed in the 'Benifuuki' group. No adverse events were reported in either group. CONCLUSIONS: 'Benifuuki' green tea containing a large amount of O-methylated EGCG reduced the symptoms of JCP and has potential as a complementary/alternative medicine for treating seasonal allergic rhinitis.

Characteristics of the Chiba environmental challenge chamber.

BACKGROUND: An environmental challenge chamber (ECC), which we refer to as the α-chamber, was built at Chiba University in 2008. The aim of this study was to validate the functionality of the ECC. METHODS: The stability of the pollen distribution and concentration in the ECC and symptoms of patients with Japanese cedar pollinosis induced by cedar pollen exposure were examined. Carryover effects of symptoms induced by different exposure protocols and correlations between symptoms induced in the ECC and those in the natural cedar pollen season were also determined. All the studies using the α-chamber were conducted out of the cedar pollen season. RESULTS: The severity of symptoms in the chamber reached a peak about 2 hours after the start of pollen exposure and plateaued thereafter. After subjects left the chamber, the symptoms persisted for several days. There was no significant difference between the severity of symptoms at exposure levels of 8000 and 12000 grains/m3. The symptoms were significantly increased by exposure for 3 consecutive days; however, there were no carryover effects in a study performed with a two-week interval. The total nasal symptom score (TNSS) in the natural pollen season showed a weak correlation with the mean TNSS on the day of exposure and the following 3 days. Symptoms in the ECC also had weak correlations with those in the early natural pollen season. CONCLUSIONS: The ECC under well-controlled conditions is suitable for clinical studies and might accelerate development of treatment for seasonal allergic rhinitis. A complete evaluation requires inclusion of the persistent reaction after subjects leave the ECC.

Determining minimal clinically important differences in Japanese cedar/cypress pollinosis patients.

BACKGROUND: Statistically significant results of medical intervention trials are not always clinically meaningful. We sought to estimate the minimal clinically important difference (MCID) (the smallest change in a given endpoint that is meaningful to a patient) during seasonal alteration of Japanese cedar/cypress pollinosis (JCCP). METHODS: Results of a double-blinded, placebo-controlled trial of JCCP patients conducted between 2008 and 2010 were analyzed using an anchor-based method in which a face scale for Japanese rhinoconjunctivitis quality-of-life questionnaire (JRQLQ) was set as an anchor. MICDs were calculated as changes of average scores, including those for naso-ocular symptoms with 5 items in diary cards (T5SS), naso-ocular symptoms with 6 items (T6SS) and QOL with 17 items on the JRQLQ when face scale scores either improved or deteriorated by one point. RESULTS: In 2009 and 2010, 3,698 and 374, respectively, grains/cm(2) of pollens were dispersed. The MCIDs for T5SS in 2009 and 2010 were 1.426 (0.285 per item) and 1.441 (0.288), respectively. The MCIDs for T6SS were 4.115 (0.686) and 3.183 (0.531) in 2009 and 2010, respectively. The MCIDs for QOL were 10.469 (0.616) and 6.026 (0.354) in 2009 and 2010, respectively. CONCLUSIONS: For T5SS in the diary, T6SS and QOL in JRQLQ, unit differences of 1.5 (0.3 per item), 3.6 (0.6) and 8.2 (0.5), respectively, were considered clinically meaningful by JCCP patients. The MCID for symptoms recorded in the diary was stable irrespective of the dispersed pollen level.