松永 佳世子

BACKGROUND: Despite the increasing prevalence of walnut allergy (WA), no allergen components have been established as markers of disease severity. This study aimed to identify proteins specifically associated with severe WA in children. METHODS: We analyzed 48 children aged 3.4-16 years who underwent an oral food challenge to walnut between February 2019 and March 2022. Children with positive and negative reactions were categorized into a WA group and walnut sensitization (WS) group, respectively. The dose-adjusted reaction severity of WA patients was quantified using the Anaphylaxis Scoring Aichi's total score divided by the cumulative protein dose that induced symptoms (TS/Pro). Using the median TS/Pro value in all cases of the WA group as a cut-off, 11 of 21 WA patients with stored sera were classified as high TS/Pro (TS/Pro ≥154.1); the remaining 10 patients were classified as low TS/Pro. Immunoblotting, mass spectrometry, and enzyme-linked immunosorbent assay (ELISA) were used to identify candidate markers of WA severity. RESULTS: Jug r 1-specific IgE (sIgE) levels were higher in the WA group, but were not significantly associated with TS/Pro. Immunoblotting and mass spectrometry detected phospholipase D alpha 1 (PLDa1) in 5/11 (45.5%) high TS/Pro patients and 1/10 (10%) low TS/Pro patients (p = .149). ELISA with recombinant PLDa1 confirmed similar results. Moreover, the absorbance of recombinant PLDa1-sIgE was significantly correlated with TS/Pro (ρ = 0.47, p = .032). CONCLUSIONS: PLDa1 (Jug r 9) is a candidate marker of WA severity. The early identification of children at risk of severe WA may aid clinicians in optimizing their management strategies.

BACKGROUND: The relationship between the severity of peanut allergy and component-specific immunoglobulin E (IgE) remains partially analyzed. We aimed to explore this relationship using a proteomic analysis of pediatric patients with peanut allergy. METHODS: Immunoblotting and mass spectrometry were used to identify candidate peanut allergen components, which were confirmed via enzyme-linked immunosorbent assay using sera from pediatric patients with peanut allergy confirmed through a positive oral food challenge test (OFC). The association between each protein-specific IgE level and the severity of peanut allergy was compared. The severity of peanut allergy was quantified as TS/Pro, which is the total score (TS) of Anaphylaxis Scoring Aichi divided by the cumulative protein dose of peanuts at the OFC (Pro). RESULTS: This study comprised 52 patients with peanut allergy. In addition to the known peanut allergen components, we discovered seven allergens in more than five participants. Among the participants, 24 (46.2%) had Annexin Gh1-specific IgE. Ara h 2 (rs = 0.67, p < .001) and Ara h 6 (rs = 0.66, p < .001) specific IgEs and the sum of the absorbance of all seven candidates (rs = 0.64, p < .001) were strongly correlated with TS/Pro. Ara h 1 (rs = 0.30, p < .05), Ara h 3 (rs = 0.37, p < .01), Ara h 7 (rs = 0.34, p < .05), and the seed biotin-containing protein SBP65 (rs = 0.35, p < .05) specific IgEs were correlated with TS/Pro. CONCLUSION: Ara h 2- and 6-specific IgEs and sensitization diversity were the most significant factors that correlated with peanut allergy severity. We identified SBP65 (Ara h 20) as a potential novel allergen component related to peanut allergy severity.

Patients with peach allergy who experience severe symptoms, including anaphylaxis, reportedly have a higher positivity for peach gibberellin-regulated protein (GRP)-specific immunoglobulin (Ig) E than those with only oral symptoms. However, a study in Italy investigating apple allergy (another Rosaceae fruit) found no clear association between apple GRP-specific IgE levels and clinical disease types. This study aimed to evaluate the clinical utility of GRP-specific IgE measurement in Japanese patients with apple allergy. We collected sera from apple-allergic patients in Japan and measured their IgE levels specific to apple GRP. Apple-allergic patients (14 with oral reactions and 14 with systemic reactions) and seven non-allergic controls were examined. The specific IgE levels against apple, Mal d 1, Mal d 4, Japanese cedar, Japanese alder, Japanese white birch, Bet v 1, and Bet v 2 were also determined using 3gAllergy™. Positive results for apple-GRP-specific IgE by enzyme-linked immunosorbent assay were obtained in one patient with oral reactions and in seven cases of systemic reactions. Exercise as a cofactor was involved in cases with high apple GRP-specific IgE. GRP expression was considerably lower in apples than in peaches, as detected by reverse transcription-quantitative polymerase chain reaction testing. Thus, GRP-specific IgE may be an important marker for diagnosing systemic reactions triggered by exercise in fruits with low GRP expression, such as apples.

Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) are potentially life-threatening severe cutaneous adverse drug reactions. These diseases are rare, and their onset is difficult to predict because of their idiosyncratic reactivity. The Japan Severe Adverse Reactions Research Group, led by the National Institute of Health Sciences, has operated a nationwide to collect clinical information and genomic samples from patients with SJS/TEN since 2006. This study evaluated the associations of clinical symptoms with sequelae and specific causative drugs/drug groups in Japanese patients with SJS/TEN to identify clinical clues for SJS/TEN treatment and prognosis. Acetaminophen, antibiotics, and carbocisteine were linked to high frequencies of severe ocular symptoms and ocular sequelae (p < 0.05). For erythema and erosion areas, antipyretic analgesics had higher rates of skin symptom affecting <10% of the skin than the other drugs, suggesting narrower lesions (p < 0.004). Hepatic dysfunction, was common in both SJS and TEN, and antiepileptic drugs carried higher risks of hepatic dysfunction than the other drug groups (p = 0.0032). This study revealed that the clinical manifestations of SJS/TEN vary according to the causative drugs.

BACKGROUND: The allergen responsible for cocamidopropyl betaine (CAPB) allergies has been debated. OBJECTIVES: To investigate the sensitizing agents of CAPB, the patch test positivity rates of impurities were examined in Japanese patients with CAPB-related allergic contact dermatitis. MATERIALS AND METHODS: Thirty patients with scalp dermatitis and positive patch tests for CAPB and/or lauramidopropyl betaine (LAPB) were enrolled in this study. They were patch tested with the detergents that they had been using at the time of their first visit and with the impurities dimethylaminopropylamine (DMAPA) and lauramidopropyl dimethylamine (LAPDMA). RESULTS: The positivity rate in patch tests of the 37 detergents that the patients had been using was 78.4% (29/37). The positivity rates of DMAPA 1% pet., 1% aq. and 0.2% aq. were 32.1% (9/28), 14.3% (4/28) and 13.3% (4/30), respectively, whereas those of LAPDMA 0.1% and 0.05% were 30.0% (9/30) and 16.7% (5/30), respectively. Among the 30 patients, 6 exhibited positive results for both DMAPA and LAPDMA, 3 showed positive results for DMAPA alone and 6 produced positive results for LAPDMA alone. CONCLUSION: Patch tests produced an overall positivity rate for DMAPA, LAPDMA or both of 50.0% (15/30) in patients with scalp dermatitis and positive patch test results for CAPB and/or LAPB.

INTRODUCTION: Screening for ω-5 gliadin specific IgE antibody (sIgE) has high diagnostic utility in cases of suspected wheat-dependent exercise-induced anaphylaxis (WDEIA); however, negative cases may require confirmatory tests, such as the oral challenge test. Thus, newly identified allergens that can be used for the serological diagnosis of WDEIA are needed. This study aimed to identify additional sIgE biomarkers of WDEIA. METHODS: Forty-two patients with WDEIA (5 negative/37 positive for ω-5 gliadin sIgE) were enrolled. For comparison, 8 patients with immediate-type wheat allergy without WDEIA and 20 healthy controls without wheat allergy were also enrolled. Extracted wheat proteins were separated by 2D-PAGE. Proteins that reacted with serum IgE antibody in 2D Western blotting (2D-WB) were identified using mass spectrometry. Recombinant proteins were synthesized in Escherichia coli, and the antigenicity was tested using ELISA and the basophil activation test. RESULTS: In 2D-WB, nine proteins reacted with the serum IgE antibody from at least 60% of patients with WDEIA (n ≥ 25/42). ELISA revealed that alpha/beta gliadin MM1 exhibited the highest positive immunoreactivity in 23 of 26 patients who were positive for ω-5 gliadin sIgE (88%) and in 5 of 5 patients who were negative for ω-5 gliadin sIgE (100%). Alpha/beta gliadin MM1 exhibited significantly higher basophil activation in 14 patients with WDEIA when compared to 5 individuals without a wheat allergy. CONCLUSIONS: Alpha/beta gliadin MM1 sIgE exhibited the highest seropositivity, even among patients who were negative for ω-5 gliadin sIgE. The inclusion of alpha/beta gliadin MM1 in allergen-sIgE tests may improve the sensitivity for diagnosing WDEIA.

Background: Allergic contact dermatitis (ACD) caused by hexavalent chromium (Cr(VI)) is often severe and difficult to treat. The content of Cr(VI) in cement can be reduced by, for example, addition of iron(II) sulfate. Since 2005 the content of Cr(VI) in cement is regulated in the EU Directive 2003/53/EC and must not exceed 2 ppm. Since this regulation came into force, ACD caused by cement has markedly been reduced. Objective: To investigate Cr(VI) and total chromium content in samples of cement from countries within and outside the EU. Methods: The members of the International Contact Dermatitis Research Group (ICDRG) were invited to participate in the study with the aim to collect cement samples from geographically different areas. The content of Cr(VI) in the samples was estimated by the diphenyl carbazide spot test, atomic absorption spectroscopy was used to assess the total chromium content. Results: Forty-five cement samples were analyzed, containing amounts of Cr(VI) from <0.1 to >70 ppm. Twenty-one samples contained >2 ppm Cr(VI), 24 contained less. Four of 17 samples from within the EU contained >2 ppm Cr(VI), that is, higher amounts than stipulated in the EU directive, as compared with 17 samples from countries outside the EU. Conclusion: In countries outside the EU, significantly more cement samples contained >2 ppm Cr(VI).

BACKGROUND: Immediate allergy caused by natto, a popular Japanese food prepared by fermenting soybeans with Bacillus subtilis var. natto, has been reported. Polygamma glutamic acid (PGA) in the sticky substance around natto beans has been reported to be a causative allergen of natto allergy. However, some of our patients with natto allergy were negative for PGA in the skin prick test (SPT). The sticky substance of natto beans contains a subtilisin family serine protease, nattokinase, along with PGA. In this study, we aimed to examine the antigenicity of nattokinase in natto allergy. METHODS: Eight patients, who developed symptoms after ingesting natto and positively reacted to natto (seven to the sticky substance in natto and one to the whole natto product) in their SPT, were enrolled in this study. To analyze IgE reactivity, we performed immunoblotting, ELISA, and SPT for natto (bean and sticky substance), and/or PGA, and/or nattokinase and/or cultured B. subtilis var. natto extract. RESULTS: In the SPT, four cases each were PGA-positive and PGA-negative. Immunoblotting of the sera from PGA-negative patients showed a protein band at 30 kDa, which was identified as nattokinase. Three PGA-negative cases, but not three PGA-positive cases, showed a positive reaction to nattokinase in the SPT and had a history of atopic dermatitis. The ELISA for nattokinase revealed a positive reaction of PGA-negative cases and negative reaction of PGA-positive cases in the SPT. CONCLUSIONS: We identified a subtilisin family serine protease, nattokinase, as a novel allergen in natto allergy patients unsensitized to PGA.