Comprehensive Genomic Characterization of Staphylococcus aureus Isolated from Atopic Dermatitis Patients in Japan: Correlations with Disease Severity, Eruption Type, and Anatomical Site.

Atopic dermatitis (AD) shows frequent recurrence. Staphylococcus aureus is the primary microbial component in AD and is associated with disease activity. However, traditional typing methods have failed to characterize virulent AD isolates at the clone level. We conducted a comprehensive genomic characterization of S. aureus strains isolated from the skin of AD patients and healthy donors, comparing the whole-genome sequences of the 261 isolates with anatomical and lesional (AD-A)/nonlesional (AD-NL)/healthy sites, eruption types, clinical scores, virulence, and antimicrobial resistance gene repertoires in Japan. Sequence type (ST) diversity was lost with worsening disease activity; ST188 was the most frequently detected ST in AD-A and had the strongest correlation with AD according to the culture rate and proportion with worsening disease activity. ST188 and ST20 isolates inhabited all skin conditions, with significantly higher proportions in AD skin than in healthy skin. ST8, ST15, and ST5 proportions were equivalent for all skin conditions; ST30 was detected only in healthy skin; and ST12 was detected only in AD skin. ST97 detected in AD-A and healthy skin was clearly branched into two subclades, designated ST97A and ST97H. A comparison of two genomes led to the discovery that only ST97A possessed the complete trp operon, enabling bacterial survival without exogenous tryptophan (Trp) on AD skin, where the Trp level was significantly reduced. Primary STs showing an AD skin inhabitation trend (ST188, ST97A, ST20, and ST12) were all trp operon positive. The predominant clones (ST188 and ST97) possessed almost no enterotoxin genes, no mecA gene, and few other antimicrobial resistance genes, different from the trend observed in Europe/North America. IMPORTANCE While Staphylococcus aureus is a member of the normal human skin flora, its strong association with the onset of atopic dermatitis (AD) has been suggested. However, previous studies failed to assign specific clones relevant to disease activities. Enterotoxins produced by S. aureus have been suggested to aggravate and exacerbate the inflammation of AD skin, but their role remains ambiguous. We conducted a nuanced comprehensive characterization of isolates from AD patients and healthy donors, comparing the whole-genome sequences of the isolates with anatomical and lesional/nonlesional/healthy sites, eruption types, clinical scores, virulence, and antimicrobial resistance gene repertoires in Japan. We demonstrate that specific clones are associated with disease severity and clinical manifestations, and the dominant clones are devoid of enterotoxin genes and antimicrobial resistance genes. These findings undermine the established notion of the pathophysiological function of S. aureus associated with AD and introduce a new concept of S. aureus colonization in AD.

Stratification of atopic dermatitis patients by patterns of response to proactive therapy with topical tacrolimus: low serum IgE levels and inadequately controlled disease activity at the start of treatment predict its failure.

PURPOSE: Topical calcineurin inhibitors (TCIs) are an important anti-inflammatory drug for treating atopic dermatitis (AD). However, those treatment responses are variable. In this study, we stratified AD patients by patterns of response to remission maintenance therapy (proactive therapy) with topical tacrolimus, a typical TCI. Thereafter, we explored patient features that predict the success or failure of proactive therapy using TCI (TCI proactive therapy). METHODS: A single-arm open-label clinical study aimed to evaluate the efficacy of TCI proactive therapy was conducted in 31 patients with AD. Patients were treated with TCS to induce remission (remission-induction period) followed by daily TCI ointment (0.1% tacrolimus) application for 4 weeks (maintenance therapy period), and twice-weekly application for 12 weeks (proactive therapy period). Based on its results, treatment outcomes were correlated with the patients' clinical and laboratory findings. RESULTS: Of the 31 patients enrolled in the study, 21 successfully completed maintenance therapy (TCI responders). Among them, 13 completed (proactive-completed group) and 8 failed proactive therapy (proactive-dropout group). At the beginning of maintenance therapy, the serum IgE level was significantly higher in the TCI responders than in those who failed maintenance therapy (p = 0.049). At the beginning of proactive therapy, the mean-SCORing Atopic Dermatitis (SCORAD) score was significantly different between the proactive-completed (11.7 ± 4.6) and proactive-dropout (16.6 ± 4.2) groups (p = 0.025). In proactive-dropout group patients, worsened disease activity correlated well with the elevation of serum lactate dehydrogenase (LDH) and Thymus and activation-regulated chemokine (TARC) levels and peripheral eosinophil count. CONCLUSION: AD patients were stratified into three different response patterns to TCI proactive therapy. Patients with less involvement of IgE in the pathogenesis and inadequate remission induction by TCS may not be expected to respond well to TCI proactive therapy.Key messagesAD patients can be stratified into three types according to their pattern of responsiveness to TCI proactive therapy.The efficacy of TCI proactive therapy is lower in AD patients with lower serum IgE levels.TCI proactive therapy should be done after the achievement of adequate remission induction by TCS.

Filaggrin-gene mutation has minimal effect on the disease severity in the lesions of atopic dermatitis.

Loss-of-function mutations of filaggrin (FLG) gene (FLG) are the strongest known genetic risk factor for atopic dermatitis (AD). It is still debatable how FLG gene mutations and the resulting abnormal amount of FLG protein contribute to skin barrier function and symptoms of AD. In this study, we examined the effects of loss-of-function mutations of FLG gene on the severity of skin lesions and skin barrier function in 55 patients with AD by evaluating eight patients with AD with FLG gene mutations and 47 patients with AD without mutations. The results showed that the FLG gene mutation did not affect the duration of AD, severity of AD, degree of local inflammatory symptoms, skin water content and trans-epidermal water loss of the lesions. Next, in these eight mutation carriers and the 47 non-carriers, stratum corneum was collected from the three site of skin lesions using tape-stripping method, and the amounts of FLG protein and total amino acid contained in the stratum corneum was measured to investigate the effect of the FLG gene mutation on the amount of FLG gene product in the local lesion. FLG abnormalities had little effect on FLG protein and total amino acid content in the stratum corneum in the lesional skin. The amount of the FLG products, especially amino acids derived from FLG, in the stratum corneum of AD lesional skin is influenced by development of dermatitis. The results obtained from this study supports that the activation of Th2-dominant inflammatory cells, together with FLG abnormality, plays a role in suppressing the production of FLG in skin lesions.

Identification of B.1.346 Lineage of SARS-CoV-2 in Japan: Genomic Evidence of Re-entry of Clade 20C.

SARS-CoV-2 whole-genome sequencing of samples from COVID-19 patients is useful for informing infection control. Datasets of these genomes assembled from multiple hospitals can give critical clues to regional or national trends in infection. Herein, we report a lineage summary based on data collected from hospitals located in the Tokyo metropolitan area. We performed SARS-CoV-2 whole-genome sequencing of specimens from 198 patients with COVID-19 at 13 collaborating hospitals located in the Kanto region. Phylogenetic analysis and fingerprinting of the nucleotide substitutions were performed to differentiate and classify the viral lineages. More than 90% of the identified strains belonged to Clade 20B, which has been prevalent in European countries since March 2020. Only two lineages (B.1.1.284 and B.1.1.214) were found to be predominant in Japan. However, one sample from a COVID-19 patient admitted to a hospital in the Kanto region in November 2020 belonged to the B.1.346 lineage of Clade 20C, which has been prevalent in the western United States since November 2020. The patient had no history of overseas travel or any known contact with anyone who had travelled abroad. Consequently, the Clade 20C strain belonging to the B.1.346 lineage appeared likely to have been imported from the western United States to Japan across the strict quarantine barrier. B.1.1.284 and B.1.1.214 lineages were found to be predominant in the Kanto region, but a single case of the B.1.346 lineage of clade 20C, probably imported from the western United States, was also identified. These results illustrate that a decentralized network of hospitals offers significant advantages as a highly responsive system for monitoring regional molecular epidemiologic trends.

Single nucleotide variations in genes associated with innate immunity are enriched in Japanese adult cases of face and neck type atopic dermatitis.

BACKGROUND: Atopic dermatitis (AD) is heterogenous in terms of phenotype as well as genetic and environmental factors, while its associated genetic factors and pathophysiology are not fully understood. OBJECTIVE: We identify novel genetic factors enriched in a subgroup of AD patients with characteristic clinical features. METHODS: We clinically subgrouped 18 AD patients who exhibited distinctive characteristic of persistent skin eruption areas on the face and neck from 92 Japanese adult AD patients and identified disease-associated genetic factors enriched within the subgroup. Targeted resequencing and subsequent genetic association analyses were used to identify novel enriched genetic variations in the subgroup compared with the other AD patients. RESULTS: Targeted resequencing of 648 skin associated genes revealed an enrichment of 12 single nucleotide variations (SNVs) in patients with face and neck AD (n = 18) compared with the general Japanese population in the database. Subsequent allele frequency comparison between the face and neck AD and non - face and neck AD subgroups revealed enrichment of five SNVs. Multivariate analysis using genotype data revealed that three SNVs in theTLR1, TIRAP, and PSAPL1 genes, two of the three genes are involved in the Toll-like receptor pathway, were significantly enriched in patients with face and neck AD. CONCLUSION: These findings revealed that the SNVs in genes associated with the innate immune pathway are enriched in a subgroup of AD. The combinational approach of clinical subgrouping and genotyping is valuable for detecting novel disease-associated genetic factors.

Assessment of skin barrier function using skin images with topological data analysis.

Recent developments of molecular biology have revealed diverse mechanisms of skin diseases, and precision medicine considering these mechanisms requires the frequent objective evaluation of skin phenotypes. Transepidermal water loss (TEWL) is commonly used for evaluating skin barrier function; however, direct measurement of TEWL is time-consuming and is not convenient for daily clinical practice. Here, we propose a new skin barrier assessment method using skin images with topological data analysis (TDA). TDA enabled efficient identification of structural features from a skin image taken by a microscope. These features reflected the regularity of the skin texture. We found a significant correlation between the topological features and TEWL. Moreover, using the features as input, we trained machine-learning models to predict TEWL and obtained good accuracy (R2 = 0.524). Our results suggest that assessment of skin barrier function by topological image analysis is promising.

Japanese guidelines for atopic dermatitis 2020.

Atopic dermatitis (AD) is a disease characterized by relapsing eczema with pruritus as a primary lesion, which is frequently encountered in clinical practice. Skin barrier dysfunction leads to enhanced skin irritability to non-specific stimuli and epicutaneous sensitization. In the lesion site, a further inflammation-related reduction in skin barrier function, enhanced irritability and scratching-related stimuli deteriorate eczema, leading to vicious cycle of inflammation. The current strategies to treat AD in Japan from the perspective of evidence-based medicine consist of three primary measures: (i) the use of topical corticosteroids and tacrolimus ointment as the main treatment for the inflammation; (ii) topical application of emollients to treat the cutaneous barrier dysfunction; and (iii) avoidance of apparent exacerbating factors, psychological counseling and advice about daily life. The guidelines present recommendations to review clinical research articles, evaluate the balance between the advantages and disadvantages of medical activities, and optimize medical activity-related patient outcomes with respect to several important points requiring decision-making in clinical practice.

Investigator-initiated clinical study of a functional peptide, SR-0379, for limb ulcers of patients with Werner syndrome as a pilot study.

AIM: An investigator-initiated clinical study was carried out to evaluate the therapeutic potency of SR-0379 for the treatment of leg ulcers in patients with Werner syndrome. METHODS: A multicenter, open-label study was carried out from September 2017 to February 2018. The inclusion criteria for leg ulcers were: (i) leg ulcers in patients with Werner syndrome, diabetes or critical limb ischemia/venous stasis; and (ii) a wound size of >1 cm and <6 cm in diameter. Four individuals with Werner syndrome and diabetic ulcers, respectively, were enrolled. SR-0379 (0.1%) was sprayed on skin ulcers once per day for 4 weeks. Efficacy was evaluated by determining the rate of wound size reduction as a primary end-point at 4 weeks after the first treatment compared with the pretreatment wound size. As secondary end-points, the DESIGN-R score index, the 50% wound size reduction ratio, time to wound closure and quantification of wound bacteria were also evaluated. The safety of SR-0379 was evaluated during the study period. RESULTS: The reduction rate of ulcer size treated with 0.1% SR-0379 was 22.90% (mean) in the Werner syndrome ulcers group (n = 4) and 35.70% (mean) in the diabetic ulcers group (n = 4), respectively. The DESIGN-R score decreased by 4.0 points in the Werner syndrome ulcers group and 4.3 points in the diabetic ulcers group. Two mild adverse events were reported in two patients, and causal relationships were denied in any events. CONCLUSION: Treatment with SR-0379 was safe, well-tolerated, and effective for leg ulcers of both Werner syndrome and diabetes patients. Geriatr Gerontol Int 2019; 19: 1118-1123.

Clinical practice guidelines for the management of atopic dermatitis 2018.

Atopic dermatitis (AD) is a disease characterized by relapsing eczema with pruritus as a primary lesion. The current strategies to treat AD in Japan from the perspective of evidence-based medicine consist of three primary measures: (i) the use of topical corticosteroids and tacrolimus ointment as the main treatment for the inflammation; (ii) topical application of emollients to treat the cutaneous barrier dysfunction; and (iii) avoidance of apparent exacerbating factors, psychological counseling and advice about daily life. The guidelines present recommendations to review clinical research articles, evaluate the balance between the advantages and disadvantages of medical activities, and optimize medical activity-related patient outcomes with respect to several important points requiring decision-making in clinical practice.

Aspergillus precipitating antibody in patients with Mycobacterium avium complex lung disease: A cross-sectional study.

RATIONALE: Little is known about the role of Aspergillus precipitating antibody (APAb) in patients with Mycobacterium avium complex lung disease (MAC-LD). OBJECTIVES: We investigated the clinical characteristics of patients with MAC-LD positive for APAb. METHODS: We conducted a cross-sectional study targeting patients with MAC-LD. APAb was checked in all participants. Clinical variables included laboratory data, pulmonary function, high-resolution computed tomography findings, and health-related quality of life. RESULTS: We analyzed 109 consecutive patients. Their median age was 68 years, and the median duration of MAC-LD was 4.8 years. Twenty (18.3%) patients tested positive for APAb. APAb-positive patients had significantly longer duration of MAC-LD (9.4 vs. 4.0 years, P = 0.017), more severe bronchiectasis evaluated by modified Reiff score (6.5 vs. 4, P = 0.0049), and lower forced expiratory volume in 1 s (%FEV1) (75.1% vs. 86.2%, P = 0.013) than APAb-negative patients. Analysis of covariance adjusted for background factors and underlying pulmonary disease revealed that %FEV1 was also significantly lower in patients with APAb (P = 0.045). Ten patients were newly diagnosed with chronic pulmonary aspergillosis (N = 5) or allergic bronchopulmonary aspergillosis (N = 5). CONCLUSIONS: APAb is associated with lower pulmonary function, and observed especially in patients with longer duration of MAC-LD and severe bronchiectasis, even in the absence of cavitary lesions.

Physician-initiated clinical study of limb ulcers treated with a functional peptide, SR-0379: from discovery to a randomized, double-blind, placebo-controlled trial.

SR-0379 is a functional peptide that has wound healing effect with anti-microbial action, making it an ideal drug to prevent infection. To evaluate the safety, efficacy, and pharmacokinetics of SR-0379 for the treatment of leg ulcers, a physician-initiated, phase I/IIa, first-in-patient clinical study was designed. A multi-center, double-blind, randomized clinical study was conducted from October 2015 to September 2016. The inclusion criteria for leg ulcers were (1) diabetes or critical limb ischemia and (2) wound size <6 cm in diameter. Twelve patients were randomized into four groups and administered 0.02%, 0.1%, or 0.5% SR-0379 or placebo treatment on skin ulcers once per day for 28 days. Efficiency was evaluated by determining the rate of wound size reduction as a primary endpoint at 4 weeks after the first treatment compared with the pre-treatment wound size. As a secondary endpoint, the DESIGN-R score index, time to wound closure, and the 50% wound size reduction ratio were also evaluated. The safety of SR-0379 was evaluated during the study period. In the evaluation of efficiency, the skin ulcer reduction rates at the last evaluation were 44.73% for the 0.02% SR-0379 group, 68.25% for the 0.1% group, and 71.61% for the 0.5% group, compared with 9.95% for the placebo group. Six adverse events were reported in four patients, of which one occurred in the placebo group, and causal relationships to study drugs were denied for all six events. Treatment with SR-0379 for chronic leg ulcers was safe, well tolerated, and effective.

Type 2 Minocycline-induced hyperpigmentation successfully treated with the novel 755 nm picosecond alexandrite laser - a case report.

BACKGROUND AND AIM: Minocycline therapy for acne vulgaris is associated with the occasional induction of various types of unsightly and often persistent hyperpigmentation, which is frequently resistant to hydroquinone treatment. Pigment-specific lasers have achieved some success with multiple treatment sessions. Recently, the picosecond domain 755 nm alexandrite laser (ps-Alex) has attracted attention in tattoo removal. The present study reports on the successful treatment, in a single ps-Alex session, of minocycline-associated pigmentation. SUBJECT AND METHOD: Subsequent to a course of minocycline, a 28-year-old Asian female developed persistent type 2 minocycline-related pigmentation on the bilateral lower extremities which was recalcitrant to hydroquinone treatment. The patient had a test treatment on a small area with a Q-switched ruby laser and the ps-Alex, following which the ps-Alex was selected for the actual treatment (spot size, 2 mm; fluence, 6.37 J/cm2; pulsewidth, 750 ps) on one leg first, followed later by the contralateral leg. RESULTS: Rapid clearance of the pigmentation was noted after a single ps-Alex session on both limbs without prolonged post-inflammatory hyperpigmentation (PIH). At one year post-treatment, clearance had been maintained. CONCLUSIONS: Our results in this single case strongly suggest that the novel 755-nm ps-Alex laser is both safe and very effective for the treatment of type 2 minocycline-induced hyperpigmentation even in PIH-prone type IV Asian skin. Further trials with larger patient populations are warranted to confirm this optimistic result.

Inflammation-free, gas-permeable, lightweight, stretchable on-skin electronics with nanomeshes.

Thin-film electronic devices can be integrated with skin for health monitoring and/or for interfacing with machines. Minimal invasiveness is highly desirable when applying wearable electronics directly onto human skin. However, manufacturing such on-skin electronics on planar substrates results in limited gas permeability. Therefore, it is necessary to systematically investigate their long-term physiological and psychological effects. As a demonstration of substrate-free electronics, here we show the successful fabrication of inflammation-free, highly gas-permeable, ultrathin, lightweight and stretchable sensors that can be directly laminated onto human skin for long periods of time, realized with a conductive nanomesh structure. A one-week skin patch test revealed that the risk of inflammation caused by on-skin sensors can be significantly suppressed by using the nanomesh sensors. Furthermore, a wireless system that can detect touch, temperature and pressure is successfully demonstrated using a nanomesh with excellent mechanical durability. In addition, electromyogram recordings were successfully taken with minimal discomfort to the user.

Clinical Practice Guidelines for the Management of Atopic Dermatitis 2016.

Atopic dermatitis (AD) is a disease characterized by relapsing eczema with pruritus as a primary lesion. Most patients have an atopic predisposition. The definitive diagnosis of AD requires the presence of all three features: (i) pruritus; (ii) typical morphology and distribution of the eczema; and (iii) chronic and chronically relapsing course. The current strategies to treat AD in Japan from the perspective of evidence-based medicine consist of three primary measures: (i) the use of topical corticosteroids and tacrolimus ointment as the main treatment for the inflammation; (ii) topical application of emollients to treat the cutaneous barrier dysfunction; and (iii) avoidance of apparent exacerbating factors, psychological counseling and advice about daily life. The guidelines present recommendations to review clinical research articles, evaluate the balance between the advantages and disadvantages of medical activities, and optimize medical activity-related patient outcomes with respect to several important points requiring decision-making in clinical practice.

Equivalence evaluation of moisturizers in atopic dermatitis patients.

Skin care with moisturizers to compensate for dry skin and decreased barrier function, and to prevent recurrence of inflammation is thought to be very important for management of atopic dermatitis. However, many patients cannot continue the use of moisturizing medications because of unpleasantness. Cosmetics may be able to compensate for such deficiencies. To evaluate the usefulness of cosmetics in maintenance of the skin in remission, we conducted a clinical trial using moisturizing cosmetics of a phospholipid preparation that showed good moisture-retaining effect in dry skin. The utility of moisturizing cosmetics was evaluated by skin findings, subjective symptoms, adverse events, moisture content of the stratum corneum, transepidermal water loss (TEWL), and a questionnaire on feel of use in comparison with a heparinoid preparation as a control product. Degree of improvement in skin findings, dryness and desquamation score, pruritus score, TEWL, and moisture content were nearly the same as with the control product. The result indicated that the moisturizing cosmetic was of equivalent effect compared with the heparinoid control preparation.

Distinct behavior of human Langerhans cells and inflammatory dendritic epidermal cells at tight junctions in patients with atopic dermatitis.

BACKGROUND: The stratum corneum and tight junctions (TJs) form physical barriers in the epidermis. Dendrites of activated Langerhans cells (LCs) extend beyond the TJs to capture external antigens in mice. LCs and inflammatory dendritic epidermal cells (IDECs) are observed in the skin of patients with atopic dermatitis (AD). OBJECTIVE: We sought to investigate the characteristics of LCs and IDECs and the distribution of their antigen capture receptors in relation to TJs in normal and AD skin. METHODS: We characterized the interactions of LCs and IDECs with TJs and the expression patterns of langerin and FcεRI by using whole-mount epidermal sheets from healthy subjects and patients with AD, ichthyosis vulgaris, and psoriasis vulgaris. RESULTS: As in mouse skin, activated LCs penetrate TJs in human skin. The number of LCs with TJ penetration increased approximately 5-fold in erythematous lesional skin of patients with AD but not in nonlesional skin of patients with AD or lesions of patients with ichthyosis vulgaris or psoriasis. In contrast, IDECs localized in the lower part of the epidermis, and their dendrites extended horizontally without penetration through TJs. Although langerin accumulated on the tips of dendrites of activated LCs, FcεRI was expressed diffusely on the cell surfaces on LCs and IDECs in lesional skin from patients with AD. CONCLUSIONS: These findings highlight interesting differences between LCs and IDECs in epidermis of patients with AD, where LCs, but not IDECs, extend dendrites through the TJs, likely to capture antigens from outside the TJ barrier with a polarized distribution of langerin but not FcεRI. These behavioral differences between skin dendritic cells might reflect an important pathophysiology of AD.

Filaggrin loss-of-function mutations are not a predisposing factor for atopic dermatitis in an Ishigaki Island under subtropical climate.

BACKGROUND: Filaggrin (FLG) is a major protein component of the stratum corneum (SC) layer, and FLG loss-of-function mutations are a predisposing factor for atopic dermatitis (AD). Previous cohort studies of children from northern and western Europe have reported FLG loss-of-function mutation frequencies of 15.1-20.9% and 5.8-13.0% in AD and non-AD groups, respectively. OBJECTIVE: To elucidate the association between AD prevalence of FLG loss-of-function mutation carriers and climate conditions, we determined the AD prevalence and FLG loss-of-function mutation frequencies in a cohort of children from Ishigaki Island. Ishigaki Island has a subtropical climate with high humidity (monthly average, 60.8-78.7%) and high temperature (monthly average, 18.5-29.4°C) throughout the year. METHODS: We diagnosed AD prevalence and analyzed eight FLG loss-of-function mutations in the Japanese population against a cohort of 721 children from the Kyushu University Ishigaki Atopic Dermatitis Study (KIDS) cohort. Parents gave consent for the mutation analysis during their medical examinations from 2001 to 2006. RESULTS: Average AD prevalence was 7.3% per year, and a total of 127 children (17.6%) were diagnosed with AD at least once between 2001 and 2006. The average total serum IgE level differed significantly between the AD and non-AD groups (199.0 and 69.0IU/ml, respectively). Although five kinds of FLG loss-of-function mutations isolated in previous Japanese FLG mutation studies were identified, the FLG loss-of-function mutation frequency in children of the KIDS cohort was not significantly different between the AD and non-AD groups (7.9% and 6.1%, respectively; P=0.174). CONCLUSION: The FLG loss-of-function mutation frequency was not significantly different between the AD and non-AD groups in a cohort of children from Ishigaki Island, which has a subtropical climate, suggesting that FLG loss-of-function mutations are not always a predisposing factor for AD prevalence.