矢上 晶子

Cosmetic and quasi-drug ingredients intended for daily use require reliable skin irritation assessment. However, restrictions on animal testing, including the European Union marketing ban for cosmetics tested on animals, have prompted the adoption of reconstructed human epidermis (RhE) assays, such as Organization for Economic Co-operation and Development (OECD) Test Guideline 439 (TG439). Although TG439 identifies Globally Harmonized System of Classification and Labelling of Chemicals (GHS) Category 2 irritants and No Category (non-irritant) chemicals as an alternative to the 4-h rabbit skin irritation test, its ability to predict human responses to 24-h exposure and mild irritation remains limited. This study evaluated the reproducibility of TG439 across six laboratories using LabCyte EPI-MODEL24 and a standardized stepwise dilution design. TG439 was used to determine a "TG439 non-irritant concentration" for 17 test substances. Human 24-h closed patch tests were then performed using stepwise escalation to one-quarter and one-half of this concentration, with predefined stopping criteria to ensure subject safety. Inter-laboratory control results confirmed TG439 reproducibility. Most test substances exhibited Sugai's Irritation Index (S.I.I.) values within the "Safe" or "Acceptable" categories at both test concentrations. However, selected surfactants, cationic preservatives, and hair dye intermediates produced elevated S.I.I. values, requiring discontinuation of concentration escalation and highlighting the importance of predefined stopping criteria. These findings support TG439 as a practical starting point for human irritation testing when combined with a stepwise concentration approach and predefined safety criteria, enabling the ethical translation of in vitro findings to human testing and extending TG439-based evaluation beyond "harmless ingredients."

PURPOSE: To report our experience with two cases of acrylate allergy confirmed by patch testing, wherein acrylic intraocular lens (IOL) implantation was performed and followed up for 1 year. OBSERVATIONS: A 78-year-old woman with an allergy to acrylic resin consulted a general allergist because of suspected depigmented contact dermatitis. A patch test was positive for methyl methacrylate and 2-hydroxyethyl methacrylate (2-HEMA), which are acrylic resins. Before cataract surgery, patch tests for the IOL and other acrylic resin materials were performed, all of which tested negative. Case 2: A 49-year-old woman was allergic to several substances, including acrylic resin. A patch test was positive for 2-HEMA and ethylene glycol dimethacrylate. We consulted an anesthesiologist regarding immediate-type allergy and explained to the patient about the possibility of IOL removal for delayed-type allergy. Intra-or postoperative complications were not observed in either patient. Postoperative inflammation was similar to that observed after conventional cataract surgeries. During the 1-year follow-up period, worsening of inflammation in the anterior chamber or other symptoms indicative of delayed hypersensitivity were not observed. CONCLUSIONS AND IMPORTANCE: In two patients with cutaneous acrylate allergy, hydrophobic acrylic IOL implantation was uneventful through the 1-year follow-up period. Careful preoperative patch testing, allergist collaboration, informed consent about uncertain long-term risk, and close follow-up are advised.

PURPOSE: Increasing attention has been paid to individuals who report gastrointestinal symptoms following wheat consumption. In addition to wheat allergy and celiac disease, non-celiac gluten sensitivity (NCGS) has been proposed as a clinical entity. Despite persistent symptoms, many affected individuals continue to consume wheat-containing foods. We aimed to investigate the impact of replacing wheat-based foods with gluten-reduced foods, specifically yellow pea pasta (YPP), bread (YPB), and chips (YPC), on the abdominal symptoms, quality of life (QOL), and gut microbiota in healthy individuals who habitually consume wheat frequently. METHODS: Thirty men and women aged 18-64 years with habitual high wheat intake were enrolled and divided into two groups based on the presence or absence of abdominal symptoms. Participants followed a 4-week gluten-reduced diet intervention using YPP, YPB, and YPC. Abdominal symptoms, QOL, gut microbiota, and selected blood biomarkers were evaluated before and after the intervention. RESULTS: The intervention led to significant improvement in abdominal distension, abdominal pain or discomfort, feeling of incomplete evacuation, hard stools, and urgent need for defecation. Baseline QOL differences between groups were no longer evident. Analysis of gut microbiota revealed maintenance and/or an increase in short-chain fatty acid-producing bacteria, with significant correlations observed between specific bacterial shifts and symptom improvement. CONCLUSIONS: Yellow pea-based products (YPP, YPB, and YPC) may represent a promising dietary strategy for alleviating abdominal symptoms in individuals with high wheat consumption. This study was registered in the UMIN Clinical Trials Registry (UMIN Trial ID: UMIN000056466).

BACKGROUND: Chronic spontaneous urticaria (CSU) is a chronic skin disorder primarily driven by mast cell activation and basophil involvement. CSU is often associated with autoimmune mechanisms, positioning Bruton's tyrosine kinase (BTK) inhibition as an attractive therapeutic strategy. TAS5315 is a once-daily oral inhibitor of BTK with activity against Tec tyrosine-protein kinase and IL-2-inducible T-cell kinase (ITK). This study evaluated the efficacy and safety of TAS5315 in patients with CSU inadequately responding to non-sedating second-generation H1 receptor antagonists (ns-antihistamines). METHODS: This Phase 2a, randomized, double-blind, parallel-group, multicenter study randomized patients (1:1:1:1:1:1) with CSU to TAS5315 4 mg, 2 mg, 1 mg, 0.5 mg, 0.25 mg, or placebo for 12 weeks. The primary endpoint was the change from baseline in Weekly Urticaria Activity Score (UAS7) at Week 12. RESULTS: Of 126 patients enrolled, all received study treatment (n = 21 per dose group). The primary endpoint, mean changes from baseline in UAS7 at Week 12 were -17.15, -16.01, -15.19, -11.63, -17.84, and -9.06 for the TAS5315 4 mg, 2 mg, 1 mg, 0.5 mg, 0.25 mg, and placebo groups, respectively. Similar improvements were observed with TAS5315 versus placebo for other efficacy endpoints. Adverse events (AEs) were reported in over half of patients in each treatment group, and most were mild in severity. The most frequently reported AE with TAS5315 was petechiae. CONCLUSIONS: Once-daily TAS5315 was well tolerated and showed promising efficacy, making it a potential treatment option for CSU patients with inadequate response to ns-antihistamines.

BACKGROUND: Cold urticaria (ColdU) is a chronic inducible urticaria characterized by the appearance of itchy wheals and/or angioedema following contact with cold. Although dupilumab treatment showed significant improvements in chronic spontaneous urticaria, there are currently no approved therapies for ColdU. OBJECTIVE: Our aim was to evaluate the efficacy and safety of dupilumab in adult and adolescent patients with ColdU who remain symptomatic despite the use of antihistamines. METHODS: LIBERTY-CINDU CUrIADS (ClinicalTrial.gov identifier NCT04681729) was a phase 3, randomized, double-blind, parallel-group, placebo-controlled, multicenter trial in which patients aged 12 years or older who had ColdU received dupilumab, 300 mg, or placebo every 2 weeks. The efficacy and safety of dupilumab were assessed after a 24-week treatment period. The primary end point was the proportion of patients with a negative ice cube provocation test result at week 24. The key secondary end points were change from baseline in Peak Pruritus Numeric Rating Scale score at the provocation site, and health-related quality of life, as measured by Dermatology Life Quality Index. RESULTS: In total, 82 adult patients were enrolled in the study. There were no statistically significant differences between the dupilumab and placebo recipients in terms of primary or secondary end points. The proportion of adult patients with ColdU with treatment-emergent adverse events was lower with dupilumab than with placebo (53.5% vs 69.2%). CONCLUSION: Dupilumab treatment did not lead to statistically significant improvements in signs and symptoms of ColdU as compared with placebo over the 24-week treatment period.

INTRODUCTION: Remibrutinib, an oral, highly selective, Bruton's tyrosine kinase (BTK) inhibitor, has shown efficacy and favorable safety in pivotal global phase 3 studies in patients with chronic spontaneous urticaria (CSU). This 52-week safety study evaluated the effect of remibrutinib in Japanese patients with CSU. METHODS: BISCUIT, a phase 3 (NCT05048342), open-label, single-arm study, investigated the safety and efficacy of remibrutinib 25 mg twice-daily as an add-on medication in Japanese patients with CSU who remain symptomatic despite treatment with H1-antihistamines. The primary endpoint was the proportion of patients with ≥ 1 adverse events (AEs). RESULTS: Overall, 71 Japanese patients (mean age 43.5 years) had a median remibrutinib exposure of 52.1 weeks; 87.3% of patients reported ≥ 1 AE, and all events were mild or moderate in severity. COVID-19 (19.7%) and headache (12.7%) were the most common AEs. Three serious AEs, unrelated to remibrutinib, were reported. No deaths occurred during the treatment period. At week 12, mean change from baseline in weekly Urticaria Activity Score (UAS7) and weekly Itch/Hives Severity Scores was - 18.1, - 8.0, and - 10.1, respectively; responses appeared to occur as early as week 1 and appeared to be sustained until week 52. Additionally, 53.6% of the patients had well-controlled disease (UAS7 ≤ 6) and 30.4% had complete absence of itch and hives (UAS7 = 0) at week 52. CONCLUSION: Remibrutinib showed a favorable safety profile and a meaningful improvement in CSU symptoms (itch and hives) at week 12, with fast improvement as early as week 1 that was sustained up to week 52, supporting its potential as an effective oral BTK inhibitor for Japanese patients with CSU. TRIAL REGISTRATION: Trial Registration: NCT05048342.

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.

OBJECTIVE: Eosinophilic gastrointestinal disorders (EGIDs) are pathologically diagnosed by manually counting the eosinophils in biopsy tissue under microscopy. However, the skill of the individual examiner is considered to influence the accuracy of the resulting eosinophil count (EC). This study aimed to examine the effects of different examiners and histopathological staining types on the EC results of pathological tissues from patients with EGIDs. METHODS: Infiltrating eosinophils in lesion tissues from 10 eosinophilic esophagitis and 28 eosinophilic gastroenteritis cases were counted by three pathologists and one cytotechnologist. The intra- and inter-observer variabilities in ECs related to hematoxylin-eosin (HE), May-Grünwald Giemsa (MG), and direct fast scarlet (DFS) staining were investigated. The effects of examiner expertise and staining method on ECs were analyzed using a linear mixed effects model. The difference in color value (ΔE) for each staining method was obtained using the Commission International de l'Eclairage luminance-a-b model (L*a*b*). RESULTS: There was no significant intra-observer variability in eosinophil counting. Regarding inter-observer agreement, the examiner with the most EGIDs experience reported higher ECs than the other examiners for all three staining types (P<0.001). ECs were significantly higher with MG and DFS staining than with HE staining, regardless of the examiner (both P<0.001). Additionally, the ΔE values with DFS were higher than those with MG and HE. CONCLUSIONS: DFS staining offered the most selective visualization of eosinophils. ECs may vary depending on both the skill of the examiner and the staining method.

OBJECTIVES: This study was conducted to investigate factors involved in anaphylaxis related to diclofenac etalhyaluronate (DEH) [product name: Joyclu® (JCL)] (containing DEH and macrogol 400), which is used to treat patients with osteoarthritis. METHODS: Patients with osteoarthritis were divided into two groups that had (experienced patients) or had not experienced anaphylactic symptoms after JCL administration (nonexperienced patients). Five tests performed to assess factors related to anaphylaxis consisted of a skin prick test as the primary endpoint and the other tests including basophil activation test, allergen-specific IgE tests using enzyme-linked immunosorbent assay or immunochromatographic kits, and genetic study were secondary endpoints. RESULTS: The skin prick test showed 4 (wheal)/7 (erythema) of 15 experienced patients and 0/3 of 19 nonexperienced patients were positive for any of the test reagents containing DEH. The basophil activation test showed two experienced patients were positive for test reagents containing DEH. DEH- and diclofenac-allergen-specific IgE were detected in 3 and 1 of 12 experienced patients, respectively. No clear results were shown in the other tests. CONCLUSIONS: DEH may be the main factor involved in the development of anaphylaxis. The skin prick test was more sensitive than the basophil activation and allergen-specific IgE tests for identifying factors associated with anaphylaxis.

BACKGROUND: The skin-prick and intradermal tests are the main diagnostic methods used to identify the causative agent in patients with suspected perioperative anaphylaxis. Although the intradermal test is more sensitive than the skin-prick test, multiple intradermal injections can be painful for children. Here, we present the case of a child with autism and suspected perioperative anaphylaxis. The causative agent was successfully identified using the intradermal test under general anesthesia. CASE PRESENTATION: An 8-year-old boy with autism developed anaphylaxis during general anesthesia for the fourth cleft lip and palate surgery. An allergic workout was performed, but both the skin-prick and basophil activation tests for suspected causative agents yielded negative results. The patient was afraid of multiple injections, and an intradermal test was performed under general anesthesia by anesthesiologists and allergists. Piperacillin was confirmed as the causative agent, and subsequent surgery using the same anesthetic agents without piperacillin was uneventful. CONCLUSIONS: Concerted efforts should be made to identify the causative agent for diagnosing perioperative anaphylaxis.

OBJECTIVE: This study was conducted to investigate the mechanisms of anaphylaxis in patients with osteoarthritis of the knee and hip after diclofenac etalhyaluronate [product name: JOYCLU® (JCL)] intra-articular injection and to determine the utility of tests to investigate the mechanism involved. METHODS: In this observational study in Japan, patients aged ≥20 years with knee or hip osteoarthritis who received JCL intra-articular injection experienced anaphylactic symptoms considered related to JCL ('experienced patients') or did not experience allergic symptoms considered related to JCL ('non-experienced patients'). Basophil activation tests (BATs), specific immunoglobulin E (IgE) antibody testing by enzyme-linked immunosorbent assays (ELISAs) or immunochromatographic kit, and genome-wide association studies (GWASs) were conducted using patient blood and saliva. RESULTS: Thirteen experienced patients and 14 non-experienced patients were tested. Seven experienced patients tested positive by BAT using diclofenac etalhyaluronate-containing test substances. Diclofenac-specific IgE antibodies were detected in four of seven BAT-positive patients but not in the non-experienced patients. Specific IgE antibody testing by immunochromatographic kit and genome-wide association study showed no clear results. CONCLUSIONS: These findings suggest that anaphylaxis occurs after JCL administration via an IgE-mediated mechanism and that diclofenac etalhyaluronate may be involved in this mechanism. BAT and diclofenac -specific IgE enzyme-linked immunosorbent assay may be useful tests for investigating the mechanisms of anaphylactic reactions after JCL administration.

BACKGROUND: Chronic spontaneous urticaria (CSU) is a chronic inflammatory disease characterized by recurrent pruritic wheals (hives) and/or angioedema. Patients with CSU could remain symptomatic despite standard-of-care H1 antihistamines (H1-AH) or anti-IgE (omalizumab) treatment. Dupilumab blocks IL-4/IL-13 signaling and is approved for multiple type 2/atopic indications. OBJECTIVE: We conducted two phase 3, randomized, placebo-controlled, double-blind trials comparing dupilumab with placebo in patients with symptomatic CSU despite H1-AH. METHODS: In LIBERTY-CSU CUPID Study A, patients were omalizumab-naive (n = 138, aged ≥6 years). In Study B, patients were omalizumab-intolerant/incomplete responders (n = 108, aged ≥12 years). The primary end point was either change from baseline over 7 days in the Urticaria Activity Score (UAS7) or Itch Severity Score (ISS7) at week 24, with the other as a key secondary end point, depending on regional regulatory requirements. Studies were pooled for safety assessment. RESULTS: In Study A, UAS7 and ISS7 improved with dupilumab versus placebo (difference -8.5 [95% CI, -13.2 to -3.9; P = .0003] and -4.2 [95% CI, -6.6 to -1.8; P = .0005]). In Study B, tested at α = 0.043 after interim analysis, UAS7 improved (difference -5.8 [95% CI, -11.4 to -0.3; P = .0390]), with a numerical trend in ISS7 (difference -2.9 [95% CI, -5.7 to -0.07; nominal P = .0449, not significant]). Pooled safety data were consistent between dupilumab and placebo and with the known dupilumab safety profile. CONCLUSIONS: Dupilumab reduced urticaria activity by reducing itch and hives severity in omalizumab-naive patients with CSU uncontrolled with H1-AH. Although the primary end point for Study B was not met, dupilumab effects were small in patients who were omalizumab-intolerant/incomplete responders.

Henna is a plant-based dye obtained from the powdered leaf of the pigmented plant Lawsonia inermis, and has often been used for grey hair dyeing, treatment, and body painting. As a henna product, the leaves of Indigofera tinctoria and Cassia auriculata can be blended to produce different colour variations. Although allergy from henna products attributed to p-phenylenediamine, which is added to enhance the dye, is reported occasionally, raw material plants of henna products could also contribute to the allergy. In this study, we reported that raw material plants of commercial henna products distributed in Japan can be estimated by LC-high resolution MS (LC-HRMS) and multivariate analysis. Principal Component Analysis (PCA) score plot clearly separated 17 samples into three groups [I; henna, II; blended henna primarily comprising Indigofera tinctoria, III; Cassia auriculata]. This grouping was consistent with the ingredient lists of products except that one sample listed as henna was classified as Group III, indicating that its ingredient label may differ from the actual formulation. The ingredients characteristic to Groups I, II, and III by PCA were lawsone (1), indirubin (2), and rutin (3), respectively, which were reported to be contained in each plant as ingredients. Therefore, henna products can be considered to have been manufactured from these plants. This study is the first to estimate raw material plants used in commercial plant-based dye by LC-HRMS and multivariate analysis.

BACKGROUND: This study aimed to elucidate the current implementation status of medical practices for adult patients with food allergies (FA) in Japan. METHODS: A survey was conducted from October to December 2021 at the allergy specialist training facilities of the Japanese Society of Allergology, examining the status of medical practices for patients with food allergies in 2019. RESULTS: Of the 819 facilities, 273 (33%) treated childhood or adult patients with FA, 8% did not treat patients with FA, and 59% did not respond to the survey. Among the facilities, 24% treated adult patients with FA across various specialties: dermatology (45%), pediatrics (37%), otolaryngology (16%), internal medicine (14%), and ophthalmology (0%). The total number of adult patients with FA at the 273 facilities was 9260, with 37% having childhood-onset and 63% having adult-onset. Among childhood-onset cases, 99% were treated in pediatric departments. The oral food challenge (OFC) was available at 198 facilities (73%), including pediatrics (94%), dermatology (66%), internal medicine (30%), and otolaryngology facilities (0%). A total of 934 OFCs were conducted in adults, of which 63% were performed in pediatric departments. CONCLUSION: Medical practices for adult patients with FA in Japan remain insufficient, with inadequate transitional care for childhood-onset cases. Strengthening medical support, including OFC for adult patients with FA, and establishing seamless transitional care is necessary.

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.

Animal testing of cosmetic ingredients and products has been banned in the European Union since 2013. However, in Japan, the application of new quasi-drugs requires the generation of data on acute oral toxicity through animal testing. A weight of evidence approach for assessing oral toxicity was challenged. This approach used a combination of safety data, including a neutral red uptake cytotoxicity assay using BALB/c3T3 cells (3T3-NRU cytotoxicity assay), which can assess the acute oral toxicity of quasi-drugs or cosmetic ingredients. We conclude that the step-by-step approach can be used to assess test substances that cause low acute oral toxicity, such as the median lethal dose (LD 50) > 2000 mg/kg, thereby avoiding animal testing.

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.

BACKGROUND: The Japanese baseline series (JBS), established in 1994, was updated in 2008 and 2015. The JBS 2015 is a modification of the thin-layer rapid-use epicutaneous (TRUE) test (SmartPractice Denmark, Hillerød, Denmark). No nationwide studies concerning the TRUE test have previously been reported. OBJECTIVES: To determine the prevalence of sensitizations to JBS 2015 allergens from 2015 to 2018. METHODS: We investigated JBS 2015 patch test results using the web-registered Skin Safety Care Information Network (SSCI-Net) from April 2015 to March 2019. RESULTS: Patch test results of 5865 patients were registered from 63 facilities. The five allergens with the highest positivity rates were gold sodium thiosulfate (GST; 25.7%), nickel sulfate (24.5%), urushiol (9.1%), p-phenylenediamine (PPD; 8.9%), and cobalt chloride (8.4%). The five allergens with the lowest positivity rates were mercaptobenzothiazole (0.8%), formaldehyde (0.9%), paraben mix (1.1%), mercapto mix (1.1%), and PPD black rubber mix (1.4%). CONCLUSIONS: Nickel sulfate and GST had the highest positivity rates. The JBS 2015, including a modified TRUE test, is suitable for baseline series patch testing.

BACKGROUND: Acne vulgaris (acne) and cutaneous resident microorganisms are considered to be closely related. However, the bacterial and fungal microbiota in the comedonal contents of inflammatory acne lesions have not yet been investigated in detail. PURPOSE: To clarify the relationship between cutaneous microorganisms and acne, we examined the microbiome in the comedonal contents of inflammatory acne and on the facial skin of patients with acne using 16s rRNA and ITS gene sequencing with a next-generation sequencer (NGS). PATIENTS AND METHODS: Twenty-two untreated Japanese acne outpatients were examined. The comedonal contents of inflammatory acne lesions on the face were collected using a comedo extractor. Skin surface samples from facial skin were collected using the swab method. RESULTS: The results obtained revealed that the predominant bacteria in the comedonal contents of inflammatory acne were Cutibacterium spp. (more prominent in areas with large amounts of sebum), while those on the skin surface were Staphylococcus spp. Malassezia spp., particularly Malassezia restricta, were the predominant fungi in both the comedonal contents of inflammatory acne and on the skin surface. The bacterial microbiome in comedonal contents exhibited stronger metabolic activity, including the production of enzymes related to acne, than that on the skin surface. CONCLUSION: These results indicate that acne is an inflammatory disease involving the overgrowth of Cutibacterium acnes and other cutaneous resident microorganisms, including Malassezia spp.

Wheat-dependent exercise-induced anaphylaxis (WDEIA) is a life-threatening food allergy triggered by wheat in combination with the second factor such as exercise. The identification of potential genetic risk factors for this allergy might help high-risk individuals before consuming wheat-containing food. We aimed to identify genetic variants associated with WDEIA. A genome-wide association study was conducted in a discovery set of 77 individuals with WDEIA and 924 control subjects via three genetic models. The associations were confirmed in a replication set of 91 affected individuals and 435 control individuals. Summary statistics from the combined set were analyzed by meta-analysis with a random-effect model. In the discovery set, a locus on chromosome 6, rs9277630, was associated with WDEIA in the dominant model (OR = 3.95 [95% CI, 2.31-6.73], p = 7.87 × 10-8). The HLA-DPB1∗02:01:02 allele displayed the most significant association with WDEIA (OR = 4.51 [95% CI, 2.66-7.63], p = 2.28 × 10-9), as determined via HLA imputation following targeted sequencing. The association of the allele with WDEIA was confirmed in replication samples (OR = 3.82 [95% CI, 2.33-6.26], p = 3.03 × 10-8). A meta-analysis performed in the combined set revealed that the HLA-DPB1∗02:01:02 allele was significantly associated with an increased risk of WDEIA (OR = 4.13 [95% CI, 2.89-5.93], p = 1.06 × 10-14). Individuals carrying the HLA-DPB1∗02:01:02 allele have a significantly increased risk of WDEIA. Further validation of these findings in independent multiethnic cohorts is needed.

A small proportion of individuals utilizing cosmetics containing rhododendrol developed leukoderma with various pathological conditions, in some cases indistinguishable from vitiligo. In this review, we investigate and evaluate the major considerations for developing rhododendrol-induced leukoderma based on data from original or review articles published in the literature to provide a wide range of information regarding the pathophysiology, mechanisms, risk evaluation, and possible mechanism-based treatments. We compile and discuss the latest information, including data related to the cytotoxicity of rhododendrol, cytoprotective functions, and involvement of the immune system, and consider the possibility of novel treatments based on the differences between individual patients and on the mechanism underlying the onset of the condition. Understanding the pathophysiology of rhododendrol-induced leukoderma helps not only elucidate the mechanisms of non-segmental vitiligo onset and progression, but also suggests prevention and treatment.

Individuals who used skin-whitening cosmetics (quasi-drugs) containing 2% rhododendrol-containing agents, developed leukoderma at a higher frequency than those who have used other skin-whitening cosmetics. The Rhododenol Research Team (RD-Team) was formed and commissioned by Kanebo Cosmetics Inc. to conduct research in treatments of rhododendrol-induced leukoderma (RDL), to evaluate effective treatment options from a medical standpoint, and provide information to a wide range of people. In this study, we evaluated the efficacy of various treatments for RDL from a medical perspective, based on the information published in the literature as original or review articles. We searched the PubMed (international) and the Igaku Chuo Zasshi (ICHUSHI) (Japanese) databases using the keywords "Rhododenol" and "rhododendrol", for articles published between July 2013 and November 2020. We discuss the main clinical findings and treatments (topical, oral, phototherapy, and surgical) of this condition based on the literature review. We found that ultraviolet light therapy is the most effective treatment for RDL. We have also summarized reports of the efficacy of oral vitamin D3 in RDL. A topical prostaglandin derivative has been reported in a new study to be effective. We have provided guidance for patients using self-tanning and skin-whitening agents to improve their quality of life. Finally, we have highlighted the importance of providing patients with information on contact dermatitis and instructing them to discontinue product use immediately if they develop any symptoms of contact dermatitis while using skin-whitening agents.

BACKGROUND: There is controversy over late and long-lasting reactions to gold sodium thiosulfate (GST). OBJECTIVES: To study the GST patch-test reaction by observing the application site after 1 month, and to clarify the relevance of GST sensitization by piercings and dental metals. PATIENTS: A retrospective analysis was performed on 746 patients (143 male; 603 female) who were patch tested using GST of the TRUE Test. We conducted a questionnaire on the presence of piercings or dental metals in these patients. RESULTS: The GST positive rate was 27.9% at day (D)3 and/or D7 and 40.3% up to the 1-month reading. The positive rate was significantly higher in female patients and increased with age. Sixty-two percent of cases with a positive reaction at D7 continued to show a positive reaction after 1 month. Eleven percent of cases with a negative reaction at D3 and D7 showed a late reaction. Both piercings and dental metals were related to gold sensitization. CONCLUSIONS: The GST of the TRUE Test had a high positive and low false-negative rate. The 1-month reading after the patch test was important for identifying late reactions. Piercing history and dental metal were associated with gold sensitization.

Racemic RS-4-(4-hydroxyphenyl)-2-butanol (rhododendrol; trade name: Rhododenol [RD]), which is used in topical skin-lightening cosmetics, was unexpectedly reported in Japan to induce leukoderma or vitiligo called RD-induced leukoderma (RIL) after repeated application. To our knowledge, no studies have investigated chemical-induced vitiligo pathogenesis on a genome-wide scale. Here, we conducted a genome-wide association study (GWAS) for 147 cases and 112 controls. CDH13, encoding a glycosylphosphatidylinositol-anchored protein called T-cadherin (T-cad), was identified as the strongest RIL susceptibility gene. RD sensitivity was remarkably increased by T-cad knockdown in cultured normal human melanocytes. Furthermore, we confirmed tyrosinase upregulation and downregulation of the anti-apoptotic molecules (BCL-2 and BCL-XL), suggesting that T-cad is associated with RD via tyrosinase or apoptotic pathway regulation. Finally, monobenzyl ether of hydroquinone sensitivity also tended to increase with T-cad knockdown, suggesting that the T-cad could be a candidate susceptibility gene for RIL and other chemical-induced vitiligo forms. This is the first GWAS for chemical-induced vitiligo, and it could be a useful model for studying the disease's genetic aspects.

We herein report a novel mutation in familial progressive hyper- and hypopigmentation (FPHH). The KITLG gene encoding the KIT ligand protein is a disease-causing gene for FPHH. Various disease-causing gain-of-function mutations, which reside within or adjacent to the conserved VTNN motif of this gene, have been described to date. We have now identified a novel KITLG mutation, c.337G>A (p.Glu113Lys), in FPHH which is located within another ligand-receptor interaction site.