Atopic dermatitis

Effects of Hyperbaric Oxygen Therapy in Children with Severe Atopic Dermatitis

In the course of atopic dermatitis (AD), the overactivity of the immune system, associated with predominant Th2 lymphocyte responses, is observed, which leads to an increased inflammatory reaction. Cases of a severe course of atopic dermatitis lead to the search for new therapeutic options. The aim of this study was to assess the effects of hyperbaric oxygen therapy (HBOT) treatment for severe cases of AD in children. A total of 15 children with severe AD underwent therapy. The influence of HBOT on the clinical course of AD and immunomodulatory effect of the therapy was analyzed by the SCORAD and objective SCORAD (oSCORAD) scales and by determining the serum concentration of immunological parameters (blood: nTreg lymphocytes, CD4+CD25highCD127-FOXP3+, NKT lymphocytes CD3+, CD16/56+, and serum: total IgE, cytokines IL-4, IL-6, and IL-10, before and after the 30-day treatment cycle). The study showed a significant effect of the therapy on the improvement of the skin condition. In all children, a reduction in the extent and intensity of skin lesions, reduction of redness, swelling, oozing/crusting, scratch marks and skin lichenification after HBOT was observed. Patients also reported a reduction in the intensity of pruritus and an improvement in sleep quality after therapy. In all children, a statistically significant decrease in the serum level of IgE was observed. However, no statistically significant changes in the blood levels of IL-4, IL-6 and IL-10, as well as the percentage of CD4⁺CD25^highCD127⁻FOXP3⁺ Treg and NKT lymphocytes, were found. In conclusion, the use of hyperbaric therapy has a positive impact on treatment results in children with a severe course of atopic dermatitis.

A Novel Multi-Action Emollient Plus Cream Improves Skin Barrier Function in Patients with Atopic Dermatitis: In vitro and Clinical Evidence

BACKGROUND

Emollients capable of restoring the skin barrier function would extend their role beyond basic maintenance therapy in atopic dermatitis (AD).

OBJECTIVES

Investigate the effect of a novel emollient plus cream (EC; Dermoflan®) on the skin barrier in vitro and in patients with mild-to-moderate AD.

METHODS

The effect of EC on the skin barrier recovery was evaluated using a tape-stripping (TS) model. After TS, organ cultures were treated with EC (undiluted or diluted 1:1 with water) and analyzed at 18-120 h using hematoxylin and eosin, Oil Red O, immunohistochemical, and immunofluorescent techniques. In a double-blind, randomized study, EC or placebo was applied once daily for 2 months to antecubital folds of the upper and lower limbs of patients with mild-to-moderate AD in clinical remission. Epidermal thickness, vascularization, and epidermal hydration were assessed by optical coherence tomography and corneometry, respectively, at baseline, and 1 and 2 months following treatment initiation.

RESULTS

Following TS, EC treatment significantly increased epidermal thickness and lipid content versus diluent in the skin organ culture, as well as claudin-1, involucrin, and caspase-14 expression, suggesting skin barrier repair. EC treatment also decreased keratin-16 expression and increased levels of Toll-like receptors 1 and 2 versus diluent, suggesting involvement in regulating the epidermal immune response. In 20 patients randomized 1:1 to EC or placebo, EC treatment at the elbow fold/popliteal fossa significantly decreased epidermal thickness after 2 months, and the number of blood vessels at the elbow fold after 1 and 2 months, versus placebo. EC significantly improved the skin hydration after 2 months versus baseline.

CONCLUSIONS

This novel multi-action EC may help to restore epidermal homeostasis and improve the skin of patients with AD. Results indicate that this novel multi-action EC could be a valid adjuvant therapy in patients with AD. Key Message: Novel multi-action emollient cream helps to restore epidermal homeostasis and improves the skin affected by AD.

Hispidulin alleviates 2,4-dinitrochlorobenzene and house dust mite extract-induced atopic dermatitis-like skin inflammation

Atopic dermatitis (AD) is a chronic inflammatory skin disorder that affects 10-20% of the world's population. Therefore, the discovery of drugs for the treatment of AD is important for human health. Hispidulin (HPD; also known as scutellarein 6-methyl ether or dinatin) is a natural flavone that exerts anti-inflammatory effects. In the present study, the effectiveness of HPD on AD-like skin inflammation was investigated. We used a mouse AD model through repeated exposure of mice to 2,4-dinitrochlorobenzene and house dust mite extract (Dermatophagoides farinae extract, DFE) to the ears. In addition, tumor necrosis factor-α and interferon-γ-activated keratinocytes (HaCaT cells) were used to investigate the underlying mechanism of HPD action. Oral administration of HPD alleviated AD-like skin inflammations: it reduced ear thickness; serum immunoglobulin (Ig)E, DFE-specific IgE, and IgG2a levels; and inflammatory cell infiltration. HPD reduced the expression of pro-inflammatory cytokines and chemokines through inhibition of signal transducer and activator of transcription 1 nuclear factor-κB in HaCaT cells. Taken together, these results suggest that HPD could be a potential drug candidate for the treatment of AD.

Keratinocytes: innate immune cells in atopic dermatitis

The skin is a unique immune organ that constitutes a complex network of physical, chemical and microbiological barriers against external insults. Keratinocytes are the most abundant cell type in the epidermis. These cells form the physical skin barrier and represent the first line of the host defense system by sensing pathogens via innate immune receptors, initiating anti-microbial responses and producing various cytokines, chemokines and anti-microbial peptides, which are important events in immunity. A damaged epidermal barrier in atopic dermatitis allows the penetration of potential allergens and pathogens to activate keratinocytes. Among the dysregulation of immune responses in atopic dermatitis, activated keratinocytes play a role in several biological processes that contribute to the pathogenesis of atopic dermatitis. In this review, we summarize the current understanding of the innate immune functions of keratinocytes in the pathogenesis of atopic dermatitis, with a special emphasis on skin-derived anti-microbial peptides and atopic dermatitis-related cytokines and chemokines in keratinocytes. An improved understanding of the innate immunity mediated by keratinocytes can provide helpful insight into the pathophysiological processes of atopic dermatitis and support new therapeutic efforts.

Current Developments of Clinical Sequencing and the Clinical Utility of Polygenic Risk Scores in Inflammatory Diseases

In this mini-review, we highlight selected research by the Deutsche Forschungsgemeinschaft (DFG) Cluster of Excellence “Precision Medicine in Chronic Inflammation” focusing on clinical sequencing and the clinical utility of polygenic risk scores as well as its implication on precision medicine in the field of the inflammatory diseases inflammatory bowel disease, atopic dermatitis and coronary artery disease. Additionally, we highlight current developments and discuss challenges to be faced in the future. Exemplary, we point to residual challenges in detecting disease-relevant variants resulting from difficulties in the interpretation of candidate variants and their potential interactions. While polygenic risk scores represent promising tools for the stratification of patient groups, currently, polygenic risk scores are not accurate enough for clinical setting. Precision medicine, incorporating additional data from genomics, transcriptomics and proteomics experiments, may enable the identification of distinct disease pathogeneses. In the future, data-intensive biomedical innovation will hopefully lead to improved patient stratification for personalized medicine.

Advancing skin delivery of α-tocopherol and γ-tocotrienol for dermatitis treatment via nanotechnology and microwave technology

This study investigated combination nanocarrier and microwave system for α-tocopherol and γ-tocotrienol delivery against dermatitis, without skin thinning effect of steroids. The vitamin E was formulated into water-rich/water-poor nanoemulsions, and had their droplet size, zeta potential, morphology, therapeutic content, encapsulation efficiency and release, in vitro skin therapeutics/nanoemulsion penetration, retention and permeation profiles, and in vivo pharmacodynamics characteristics examined, with skin pre-treated by precision microwave when applicable. The nanoemulsions had droplet sizes <150 nm and negative zeta potential values. The skin pre-treatment by microwave (1 mW/3985 MHz) promoted therapeutics accumulation in epidermis through enhancing nanoemulsion penetration into skin. The combination nano- and microwave technologies fluidized skin lipid and protein domains with epidermal microstructures being fluidized to a greater extent than dermis, allowing a relatively high epidermal-to-dermal nanoemulsion distribution. Microwave of lower or higher than 3985 MHz brought about lower skin therapeutics/nanoemulsion accumulation due to insufficient lipid/protein domain fluidization or microwave-skin interaction limiting at skin surfaces only. Using water-rich nanoemulsion with higher therapeutic release and skin pre-treatment with 3985 MHz microwave, dermatitis was alleviated in vivo without skin thinning of standard steroid. The use of combination microwave and nanotechnology promotes vitamin delivery and translates to positive dermatitis treatment outcome that warrants future investigation.

Persistence of mature dendritic cells, TH2A, and Tc2 cells characterize clinically resolved atopic dermatitis under IL-4Rα blockade

Therapeutic options for autoimmune diseases typically consist of broad and targeted immunosuppressive agents. However, sustained clinical benefit is rarely achieved, as the disease phenotype usually returns after cessation of treatment. To better understand tissue-resident immune memory in human disease, we investigated patients with atopic dermatitis (AD) who underwent short-term or long-term treatment with the IL-4Rα blocker dupilumab. Using multi-omics profiling with single-cell RNA sequencing and multiplex proteomics, we found significant decreases in overall skin immune cell counts and normalization of transcriptomic dysregulation in keratinocytes consistent with clearance of disease. However, we identified specific immune cell populations that persisted for up to a year after clinical remission while being absent from healthy controls. These populations included LAMP3 + CCL22+ mature dendritic cells, CRTH2 + CD161 + T helper ("TH2A") cells, and CRTAM + cytotoxic T cells, which expressed high levels of CCL17 (dendritic cells) and IL13 (T cells). TH2A cells showed a characteristic cytokine receptor constellation with IL17RB, IL1RL1 (ST2), and CRLF2 expression, suggesting that these cells are key responders to the AD-typical epidermal alarmins IL-25, IL-33, and TSLP, respectively. We thus identified disease-linked immune cell populations in resolved AD indicative of a persisting disease memory, facilitating a rapid response system of epidermal-dermal cross-talk between keratinocytes, dendritic cells, and T cells. This observation may help to explain the disease recurrence upon termination of immunosuppressive treatments in AD, and it identifies potential disease memory-linked cell types that may be targeted to achieve a more sustained therapeutic response.

Prevalencia de asma en niños con dermatitis atópica

Introducción: La dermatitis atópica (DA) se ha relacionado con diferentes enfermedades inmunológicas como alergias alimentarias, asma o rinitis; conocida esta relación como “marcha atópica”. Objetivo: Determinar la prevalencia de asma en pacientes pediátricos de 0 a 12 años con dermatitis atópica en la población de pacientes evaluados en la consulta externa de INDERMA, zona 1 de la Ciudad de Guatemala, durante un período de 6 meses. Metodología: Estudio observacional transversal y descriptivo en el cual se incluyeron pacientes pediátricos con diagnóstico de dermatitis atópica. Resultados: Se obtuvo una muestra de 316 pacientes con DA y se determinó una prevalencia de 19% de asma. Se encontró que en la clasificación por severidad de DA fue leve en un 52%. La mayoría de los pacientes asmáticos presentaban una forma moderada de la enfermedad (27%). La DA es más común en lactantes de 0 a 4 años y se muestra más leve a mayor edad. Conclusión: Se estableció que la prevalencia de asma en los pacientes con DA en el Instituto de Dermatología y Cirugía de Piel zona 1 fue de un 19%.

Epithelial-Mesenchymal Transition in Atopy: A Mini-Review

Atopic diseases, particularly atopic dermatitis (AD), asthma, and allergic rhinitis (AR) share a common pathogenesis of inflammation and barrier dysfunction. Epithelial to mesenchymal transition (EMT) is a process where epithelial cells take on a migratory mesenchymal phenotype and is essential for normal tissue repair and signal through multiple inflammatory pathways. However, while links between EMT and both asthma and AR have been demonstrated, as we outline in this mini-review, the literature investigating AD and EMT is far less well-elucidated. Furthermore, current studies on EMT and atopy are mostly animal models or ex vivo studies on cell cultures or tissue biopsies. The literature covered in this mini-review on EMT-related barrier dysfunction as a contributor to AD as well as the related (perhaps resultant) atopic diseases indicates a potential for therapeutic targeting and carry treatment implications for topical steroid use and environmental exposure assessments. Further research, particularly in vivo studies, may greatly advance the field and translate into benefit for patients and families.

Improvement of clinical and immunological parameters after allergen-specific immunotherapy in atopic dermatitis

BACKGROUND

Allergen immunotherapy (AIT) is considered a curative treatment in some atopic diseases, but in AD contradictory clinical results exist and the action of AIT has not been elucidated. In the literature, there is no evidence for parallel investigations of permeability barrier, cutaneous and blood immune responses after AIT in AD.

OBJECTIVES

The objective was to investigate immune parameters in the blood and skin and to detect clinical and barrier changes after AIT in AD.

METHODS

Mild-to-moderate AD patients (n = 14) with concomitant allergic rhinitis to house dust mites were selected. All patients received topical treatment, while eight patients were randomly selected for adjuvant AIT also. At baseline and after 6 months, clinical, barrier and immunological investigations (serum and skin tests) were performed. In selected patients, biopsies from atopy patch tests (APTs) were analysed by immunohistochemistry for AD-relevant immune cells and mediators.

RESULTS

In the adjuvant AIT group, clinical parameters and barrier functions improved significantly. Blood immune parameters displayed no significant changes. Post-AIT APT became negative in all patients in the AIT group, but remained positive in the non-AIT group. Cutaneous dendritic cell and T-cell recruitment decreased significantly after allergen challenge in the AIT group, but no significant changes in skin or serum immunoglobulin E levels or prick test (SPT) reactivity were detected.

CONCLUSIONS

Allergen immunotherapy is a beneficial adjuvant treatment for sensitized AD patients. AIT improves not only clinical symptoms, but also permeability barrier functions. The effect of AIT on sensitization should be detected by APT, not by SPT.

Dietary prebiotics promote intestinal Prevotella in association with a low-responding phenotype in a murine oxazolone-induced model of atopic dermatitis

Atopic dermatitis is a chronic eczema commonly observed among children in Western countries. The gut microbiota is a significant factor in the pathogenesis, and ways to promote intestinal colonizers with anti-inflammatory capabilities are therefore favorable. The present study addressed the effects of a prebiotic, xylooligosaccharide (XOS), on the gut microbiota and ear inflammation in an oxazolone-induced dermatitis model in BALB/c mice. Mice were fed a XOS supplemented or a control diet throughout the experiment. Ear thickness and clinical skin inflammation were scored blindly after three weeks topical challenge with 0.4% oxazolone. The mice were divided into high and low responders to oxazolone-induced dermatitis based on clinical inflammation and histological evaluation of ear biopsies, and significantly fewer high responders were present in the XOS fed group. In addition, XOS fed mice had higher abundance of Prevotella spp. in their gut microbiota compared to the control fed mice. Serum IgE and ear tissue cytokine levels correlated significantly with the clinical scores, and with the abundance of Prevotella spp. The strong association between the low-responding phenotype and high abundance of Prevotella spp., indicates an alleviating effect of this intestinal colonizer in allergic sensitization. Prevotella should be considered as a relevant target for future microbiota-directed treatment strategies in atopic patients.

Improved Anti-Inflammatory Effects of Liposomal Astaxanthin on a Phthalic Anhydride-Induced Atopic Dermatitis Model

Previously, we found that astaxanthin (AST) elicited an anti-inflammatory response in an experimental atopic dermatitis (AD) model. However, the use of AST was limited because of low bioavailability and solubility. We hypothesized that liposome formulation of AST could improve this. In this study, we compared the anti-inflammatory and anti-dermatotic effects of liposomal AST (L-AST) and free AST. We evaluated the effect of L-AST on a phthalic anhydride (PA)-induced animal model of AD by analyzing morphological and histopathological changes. We measured the mRNA levels of AD-related cytokines in skin tissue and immunoglobulin E concentrations in the serum. Oxidative stress and transcriptional activities of signal transducer and activator of transcription 3 (STAT3) and nuclear factor (NF)-κB were analyzed via western blotting and enzyme-linked immunosorbent assay. PA-induced dermatitis severity, epidermal thickening, and infiltration of mast cells in skin tissues were ameliorated by L-AST treatment. L-AST suppressed AD-related inflammatory mediators and the inflammation markers, inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 in PA-induced skin conditions. Oxidative stress and expression of antioxidant proteins, glutathione peroxidase-1 (GPx-1) and heme oxygenase-1 (HO-1), were recovered by L-AST treatment in skin tissues from PA-induced mice. L-AST treatment reduced transcriptional activity of STAT3 and NF-κB in PA-induced skin tissues. Our results indicate that L-AST could be more effective than free AST for AD therapy.

Lactobacillus paracasei KBL382 administration attenuates atopic dermatitis by modulating immune response and gut microbiota

Administration of probiotics has been linked to immune regulation and changes in gut microbiota composition, with effects on atopic dermatitis (AD). In this study, we investigated amelioration of the symptoms of AD using Lactobacillus paracasei KBL382 isolated from the feces of healthy Koreans. Mice with Dermatophagoides farinae extract (DFE)-induced AD were fed 1 × 10⁹ CFU d^-1 of L. paracasei KBL382 for 4 weeks. Oral administration of L. paracasei KBL382 significantly reduced AD-associated skin lesions, epidermal thickening, serum levels of immunoglobulin E, and immune cell infiltration. L. paracasei KBL382-treated mice showed decreased production of T helper (Th)1-, Th2-, and Th17-type cytokines, including thymic stromal lymphopoietin, thymus, and activation-regulated chemokine, and macrophage-derived chemokine, and increased production of the anti-inflammatory cytokine IL-10 and transforming growth factor-β in skin tissue. Intake of L. paracasei KBL382 also increased the proportion of CD4+ CD25+ Foxp3+ regulatory T cells in mesenteric lymph nodes. In addition, administration of L. paracasei KBL382 dramatically changed the composition of gut microbiota in AD mice. Administration of KBL382 significantly ameliorates AD-like symptoms by regulating the immune response and altering the composition of gut microbiota.

Lactobacillus paracasei KBL382 administration attenuates atopic dermatitis by modulating immune response and gut microbiota

Administration of probiotics has been linked to immune regulation and changes in gut microbiota composition, with effects on atopic dermatitis (AD). In this study, we investigated amelioration of the symptoms of AD using Lactobacillus paracasei KBL382 isolated from the feces of healthy Koreans. Mice with Dermatophagoides farinae extract (DFE)-induced AD were fed 1 × 10⁹ CFU d^-1 of L. paracasei KBL382 for 4 weeks. Oral administration of L. paracasei KBL382 significantly reduced AD-associated skin lesions, epidermal thickening, serum levels of immunoglobulin E, and immune cell infiltration. L. paracasei KBL382-treated mice showed decreased production of T helper (Th)1-, Th2-, and Th17-type cytokines, including thymic stromal lymphopoietin, thymus, and activation-regulated chemokine, and macrophage-derived chemokine, and increased production of the anti-inflammatory cytokine IL-10 and transforming growth factor-β in skin tissue. Intake of L. paracasei KBL382 also increased the proportion of CD4+ CD25+ Foxp3+ regulatory T cells in mesenteric lymph nodes. In addition, administration of L. paracasei KBL382 dramatically changed the composition of gut microbiota in AD mice. Administration of KBL382 significantly ameliorates AD-like symptoms by regulating the immune response and altering the composition of gut microbiota.

Early transcriptional changes after UVB treatment in atopic dermatitis include inverse regulation of IL-36γ and IL-37

Phototherapy with narrow-band Ultraviolet B (nb-UVB) is a major therapeutic option in atopic dermatitis (AD), yet knowledge of the early molecular responses to this treatment is lacking. The objective of this study was to map the early transcriptional changes in AD skin in response to nb-UVB treatment. Adult patients (n = 16) with AD were included in the study and scored with validated scoring tools. AD skin was irradiated with local nb-UVB on day 0, 2 and 4. Skin biopsies were taken before and after treatment (day 0 and 7) and analysed for genome-wide modulation of transcription. When examining the early response after three local UVB treatments, gene expression analysis revealed 77 significantly modulated transcripts (30 down- and 47 upregulated). Among them were transcripts related to the inflammatory response, melanin synthesis, keratinization and epidermal structure. Interestingly, the pro-inflammatory cytokine IL-36γ was reduced after treatment, while the anti-inflammatory cytokine IL-37 increased after treatment with nb-UVB. There was also a modulation of several other mediators involved in inflammation, among them defensins and S100 proteins. This is the first study of early transcriptomic changes in AD skin in response to nb-UVB. We reveal robust modulation of a small group of inflammatory and anti-inflammatory targets, including the IL-1 family members IL36γ and IL-37, which is evident before any detectable changes in skin morphology or immune cell infiltrates. These findings provide important clues to the molecular mechanisms behind the treatment response and shed light on new potential treatment targets.

Single-cell transcriptomics combined with interstitial fluid proteomics defines cell type-specific immune regulation in atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is the most common chronic inflammatory skin disease, but its complex pathogenesis is only insufficiently understood, resulting in still limited treatment options.

OBJECTIVE

We sought to characterize AD on both transcriptomic and proteomic levels in humans.

METHODS

We used skin suction blistering, a painless and nonscarring procedure that can simultaneously sample skin cells and interstitial fluid. We then compared results with conventional biopsies.

RESULTS

Suction blistering captured epidermal and most immune cells equally well as biopsies, except for mast cells and nonmigratory CD163+ macrophages that were only present in biopsy isolates. Using single-cell RNA sequencing, we found comparable transcriptional profiles of key inflammatory pathways between blister and biopsy AD, but suction blistering was superior in cell-specific resolution for high-abundance transcripts (KRT1/KRT10, KRT16/KRT6A, S100A8/S100A9), which showed some background signals in biopsy isolates. Compared with healthy controls, we found characteristic upregulation of AD-typical cytokines such as IL13 and IL22 in Th2 and Th22 cells, respectively, but we also discovered these mediators in proliferating T cells and natural killer T cells, that also expressed the antimicrobial cytokine IL26. Overall, not T cells, but myeloid cells were most strongly enriched in AD, and we found dendritic cell (CLEC7A, amphiregulin/AREG, EREG) and macrophage products (CCL13) among the top upregulated proteins in AD blister fluid proteomic analyses.

CONCLUSION

These data show that by using cutting-edge technology, suction blistering offers several advantages over conventional biopsies, including better transcriptomic resolution of skin cells, combined with proteomic information from interstitial fluid, unraveling novel inflammatory players that shape the cellular and proteomic microenvironment of AD.

Bioengineered Skin Intended as In Vitro Model for Pharmacosmetics, Skin Disease Study and Environmental Skin Impact Analysis

This review aims to be an update of Bioengineered Artificial Skin Substitutes (BASS) applications. At the first moment, they were created as an attempt to replace native skin grafts transplantation. Nowadays, these in vitro models have been increasing and widening their application areas, becoming important tools for research. This study is focus on the ability to design in vitro BASS which have been demonstrated to be appropriate to develop new products in the cosmetic and pharmacology industry. Allowing to go deeper into the skin disease research, and to analyze the effects provoked by environmental stressful agents. The importance of BASS to replace animal experimentation is also highlighted. Furthermore, the BASS validation parameters approved by the OECD (Organisation for Economic Co-operation and Development) are also analyzed. This report presents an overview of the skin models applicable to skin research along with their design methods. Finally, the potential and limitations of the currently available BASS to supply the demands for disease modeling and pharmaceutical screening are discussed.

Saponin from Periploca forrestii Schltr Mitigates Oxazolone-Induced Atopic Dermatitis via Modulating Macrophage Activation

Atopic dermatitis (AD) is a relapsing, acute, and chronic skin disease featured by intractable itching, eczematous skin. Conventional therapies based on immunosuppression such as corticosteroids are associated with multiple adverse reactions. Periploca forrestii Schltr saponin (PFS) was shown to potently inhibit murine arthritis by protecting bone and cartilage injury and suppressing NF-κB activation. However, its therapeutic effect on oxazolone-induced atopic dermatitis (AD) and the underlying mechanisms on macrophage are still unclear. The AD-like dermatitis was induced by repeated oxazolone challenge to the skin of BALB/c mice in vivo. Blood and ears were biochemically or histologically processed. RT-PCR, western blotting, and ELISA were conducted to evaluate the expression of macrophage factors. Mouse bone marrow-derived macrophages (BMDMs) stimulated with lipopolysaccharide (LPS) were used as a model in vitro. PFS treatment inhibited AD-like dermatitis development. PFS downregulated epidermis thickness and cell infiltration, with histological analysis of the skin lesion. PFS alleviated plasma immunoglobulin (Ig) E, IgG2a, and IgG1 levels. PFS downregulated the expression of M1 macrophage factors, tumor necrosis factor- (TNF-) α, interleukin- (IL-) 6, monocyte chemotactic protein-1 (MCP-1), and nitric oxide synthase2 (NOS2), and M2 macrophage factors, IL-4, arginase1 (Arg1) and CD163 in AD-like skin, which were confirmed by western blot and ELISA analysis. In addition, PFS inhibited LPS-induced macrophage polarization via the inhibition of the phosphorylation of signal transducer and activator of transcription 3 (STAT3) and nuclear translocation of NF-κB p65. These results suggest that PFS exerted an antidermatitis effect against oxazolone by modulating macrophage activation. PFS administration might be useful in the treatment of AD and inflammatory skin diseases.

Investigating causal relationships between Body Mass Index and risk of atopic dermatitis: a Mendelian randomization analysis

Population studies suggest that atopic dermatitis (AD) is associated with an increased risk of obesity, however a causal relationship between these two conditions remains to be established. We therefore use Mendelian randomization (MR) to evaluate whether obesity and AD are causally interlinked. We used summary statistics extracted from genome wide association studies of Body Mass Index (BMI) and AD. MR analysis was performed in both directions to establish the direction of causality between BMI and AD. We find that genetically determined increase in adiposity is associated with increased risk of AD (odds ratio of AD 1.08 [95% CI 1.01 to 1.14; p = 0.015] per unit increase in BMI). Conversely, genetically determined increased risk of AD is not associated with a higher BMI (change in BMI attributable to AD based on genetic information: 0.00; 95% CI − 0.02 to 0.02; p = 0.862). There was no evidence for confounding of these genetic analyses by horizontal pleiotropy. Our results indicate that the association of AD with obesity is likely to reflect a causal role for adiposity in the development of AD. Our findings enhance understanding of the etiology of AD, and the basis for experimental studies to evaluate the mechanistic pathways by which adiposity promotes AD.

New and Emerging Biologics for Atopic Dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease that is characterized by complex pathophysiology involving both skin barrier dysfunction and aberrant type 2 inflammation/immune responses. AD can be a debilitating condition that drastically impairs quality of life, especially in patients with moderate-to-severe disease. Currently, topical therapies such as corticosteroids and non-steroidal immunomodulatory therapy provide limited efficacy for patients with moderate-to-severe AD; limitations include inadequate response, cutaneous toxicity from overuse, and poor tolerance due to stinging and burning. Historically, the development of targeted therapies has been challenging due to the complex and multifaceted etiology of AD. Recent progress in understanding the immunopathology of AD reinforces the development of newly targeted therapeutics. The successful launch of dupilumab, a monoclonal antibody targeting the interleukin (IL)-4α receptor subunit, for AD in 2017 spurred the development of a number of biologics targeting novel cytokine and receptor targets that are now in phase II and III of development. This review aims to explore the rationale behind these novel biological therapies and to summarize current clinical studies of these agents.

'Barrier dysfunction in Atopic newBorns studY' (BABY): protocol of a Danish prospective birth cohort study

INTRODUCTION

Skin barrier development and dysfunction in premature and mature newborns is important for the risk of atopic dermatitis (AD).

METHODS AND ANALYSIS

The Barrier dysfunction in Atopic newBorns studY (BABY) Cohort is a prospective birth cohort study of 150 preterm children (gestational age (GA) below 37+0) and 300 term children (GA 37+0 to 41+6). Skin barrier is assessed through transepidermal water loss, tape stripping, Raman-spectroscopy and microbiome sampling. Clinical examinations are done and DNA from buccal swabs is collected for genetic analyses. Thymus size is assessed by ultrasound examination. Information on pregnancy, delivery, parental exposures and diseases are collected, and structured telephone interviews are conducted at 18 and 24 months to assess exogenous exposures in the child and onset of AD. Hanifin and Rajka criteria as well as The UK Working Party's Diagnostic Criteria for Atopic Dermatitis are used to diagnose AD. Severity of AD is assessed using the Eczema Area and Severity Index (EASI) and Patient Oriented Eczema Measure (POEM).

ETHICS AND DISSEMINATION

The study is approved by the scientific Ethical Committee of the Capital Region (H-16042289 and H-16042294).Outcomes will be presented at national and international conferences and in peer-reviewed publications.

Transcriptomes from German shepherd dogs reveal differences in immune activity between atopic dermatitis affected and control skin

Canine atopic dermatitis (CAD) is an inflammatory and pruritic allergic skin disease with both genetic and environmental risk factors described. We performed mRNA sequencing of non-lesional axillary skin biopsies from nine German shepherd dogs. Obtained RNA sequences were mapped to the dog genome (CanFam3.1) and a high-quality skin transcriptome was generated with 23,510 expressed gene transcripts. Differentially expressed genes (DEGs) were defined by comparing three controls to five treated CAD cases. Using a leave-one-out analysis, we identified seven DEGs: five known to encode proteins with functions related to an activated immune system (CD209, CLEC4G, LOC102156842 (lipopolysaccharide-binding protein-like), LOC480601 (regakine-1-like), LOC479668 (haptoglobin-like)), one (OBP) encoding an odorant-binding protein potentially connected to rhinitis, and the last (LOC607095) encoding a novel long non-coding RNA. Furthermore, high mRNA expression of inflammatory genes was found in axillary skin from an untreated mild CAD case compared with healthy skin. In conclusion, we define genes with different expression patterns in CAD case skin helping us understand post-treatment atopic skin. Further studies in larger sample sets are warranted to confirm and to transfer these results into clinical practice.

Dupilumab provides rapid and sustained improvement in SCORAD outcomes in adults with moderate-to-severe atopic dermatitis: combined results of four randomized phase 3 trials

Background: Dupilumab, a first-in-class therapy targeting the two key cytokines involved in the persistent underlying inflammatory pathway in atopic dermatitis (AD), is approved for treatment of moderate-to-severe AD in Europe, USA, Japan and several other countries. Objective: To assess dupilumab effects on SCORing Atopic Dermatitis (SCORAD) and component scores (objective and subjective SCORAD) over time in adults with moderate-to-severe AD. Methods: This post hoc analysis included 2,444 patients in four placebo-controlled, double-blind, randomized, phase 3 trials. SOLO 1 and 2 (NCT02277743; NCT02277769) evaluated 16 weeks of dupilumab monotherapy against placebo. CAFÉ (NCT02755649) and CHRONOS (NCT02260986) evaluated dupilumab with concomitant topical corticosteroids (TCS) against TCS alone for 16 and 52 weeks, respectively. Results: 2,444 patients randomized to treatment in SOLO 1 and 2 (N = 1,379), CAFÉ (N = 325) and CHRONOS (N = 740) were analyzed. Dupilumab treatment significantly improved overall SCORAD and individual components as early as Week 1 or 2, with significant and clinically meaningful differences vs. control through end of treatment (p < .0001). These results occurred irrespective of dupilumab regimen, 300 mg subcutaneously weekly or every 2 weeks. Conclusions: In four large phase 3 trials in adults with moderate-to-severe AD, dupilumab treatment with or without concomitant TCS resulted in rapid and sustained improvements in all SCORAD outcomes vs. placebo or TCS alone.

German S1 guidelines for the diagnosis and treatment of perianal dermatitis (anal eczema)

Perianal dermatitis (anal eczema, perianal eczema) is one of the most common proctological conditions. It may occur as a sequela or a presenting symptom of various proctological, dermatological, allergic or pathogen-induced disorders. The three main types of anal eczema are irritant-toxic, atopic and allergic contact dermatitis. Adequate and successful treatment requires a comprehensive diagnostic workup to determine disease etiology and includes treatment/elimination of causative factors as well as nonpharmacological interventions (avoidance of aggravating factors). In addition, adjuvant topical anti-inflammatory and/or specific symptomatic treatment may be required. The present guidelines contain recommendations for the diagnostic and therapeutic management of perianal dermatitis. Target users of these guidelines are clinicians in the fields of dermatology and proctology, as well as all other specialties involved in the management of patients with perianal dermatitis, both in hospital and office-based settings.

Crisaborole Ointment, 2%, for Treatment of Patients with Mild-to-Moderate Atopic Dermatitis: Systematic Literature Review and Network Meta-Analysis

Introduction

There is a need to compare efficacy and safety profiles of crisaborole ointment, 2%, versus other topical treatments across randomized clinical trials (RCTs). We performed this review/network meta-analysis to evaluate the comparative efficacy and safety of crisaborole versus other topical pharmacologic therapies for mild-to-moderate atopic dermatitis (AD) among patients aged ≥ 2 years.

Methods

Searches were conducted in MEDLINE, Embase, the Cochrane Collection Central Register of Clinical Trials, and the Database of Abstracts of Reviews of Effects using Ovid to identify English language articles reporting RCTs of topical anti-inflammatory agents in patients aged ≥ 2 years with mild-to-moderate AD published between inception and 10 March 2020. This review used a prespecified protocol with eligibility criteria for population, interventions, comparisons, outcomes, and study design. Efficacy was evaluated using the Investigator’s Static Global Assessment (ISGA) of clear (0) or almost clear (1) and expressed by hazard ratios (HR) with 95% credible intervals.

Results

Patients treated with crisaborole or tacrolimus ointment, 0.1% or 0.03%, versus vehicle alone were significantly more likely to achieve ISGA 0/1 at 28–42 days, with the greatest point estimate observed for the crisaborole comparison (hazard ratio: 2.07; 95% credible interval 1.76 to − 2.36; probability HR above 1 [p better]: 100.0%). Patients were also more likely to achieve ISGA 0/1 with crisaborole than with pimecrolimus cream, 1% (HR: 1.62; 95% credible interval 1.04–2.48; p better: 98.3%). While network meta-analysis for safety was not feasible because of data limitations, crisaborole pivotal studies (AD-301/AD-302) showed crisaborole was well tolerated.

Conclusions

Crisaborole was shown to be superior to vehicle and pimecrolimus and comparable to tacrolimus, 0.1% or 0.03%, with respect to ISGA 0/1 at 28–42 days in patients aged ≥ 2 years with mild-to-moderate AD. This evaluation of comparative efficacy of crisaborole further supports use of crisaborole as an effective therapeutic option in this population.

Electronic supplementary material

The online version of this article (10.1007/s13555-020-00389-5) contains supplementary material, which is available to authorized users.

Efficacy of biologics in atopic dermatitis

Introduction: Atopic dermatitis (AD) is a heterogeneous disease. Recent advancements in understanding AD pathogenesis resulted in the exponential expansion of its therapeutic pipeline, particularly following the success and FDA-approval of dupilumab. Different phenotypes of AD by age and ethnicity have also recently been described and clinical studies of emerging treatments will further clarify the role of each cytokine pathway in AD.Areas covered: We review the impressive repertoire of biologics for treatment of moderate-to-severe AD, including those targeting Th2, Th22, Th17/IL-23 and IgE. We highlight the scientific rationale behind each approach and provide a discussion of the most recent clinical efficacy and safety data.Expert opinion: AD is a complex disease and recent research has identified numerous endotypes, reinforcing the rationale for developing targeted therapeutics to antagonize these factors. Dupilumab has revolutionized AD treatment and its mechanistic studies also offer crucial insight into AD pathogenesis. Nevertheless, this biologic does not work for everyone, highlighting the need for a more precise approach to address the unique immune fingerprints of each AD subset. Ultimately targeted therapeutics will complement our understanding of the AD molecular map and help push AD management into an era of personalized medicine.

Itch regulation of innate and adaptive immune responses in mice and humans

The E3 ubiquitin ligase Itch has long been appreciated to be a critical suppressor of inflammation, first identified as a regulator of Th2 differentiation and lung inflammation. Recent studies have revealed novel roles for this protein in mouse and human disease, and it is now clear that Itch also limits the function of other lymphocytes, innate immune cells, and nonhematopoietic cells to regulate immunity. In addition to Th2 cells, Itch also regulates Th17 and regulatory T cells. Itch regulates humoral immunity through direct roles in T follicular helper cells and T follicular regulatory cells, and B cells. Furthermore, Itch limits innate immune responses, such as macrophage cytokine production. Through these cell-intrinsic functions, Itch regulates the interplay between innate and adaptive immune cells, resulting in profound autoinflammation in Itch-deficient mice. Whereas Itch deficiency was previously thought to be an extremely rare occurrence humans, whole exome sequencing of patients with unexplained autoimmune disease has revealed at least two additional cases of Itch deficiency in the last year alone, each caused by distinct mutations within the Itch gene. The recent identification of these patients suggests that Itch mutations may be more common than previously thought, and demonstrates the need to understand how this protein regulates inflammation and autoimmune disease.

Lipid depletion enables permeation of Staphylococcus aureus bacteria through human stratum corneum

Atopic dermatitis (AD) is a chronic inflammatory disease that affects approximately 2-5% of adults worldwide. The pathogenesis of AD continues to be a well-debated point of conjecture, with numerous hypotheses having been proposed. AD conditions are associated with increased populations of Staphylococcus aureus and reduced skin lipids. In this study, we evaluate the ability of S. aureus to permeate across human stratum corneum (SC) exhibiting both normal and depleted lipid conditions consistent with AD. This permeation would enable bacteria to interact with underlying viable epidermal cells, which could serve as a trigger for inflammation and disease onset. Our results indicate that permeation of S. aureus through SC exhibiting normal lipid conditions is not statistically significant. However, bacteria can readily permeate through lipid depleted tissue over a 9-d period. These findings suggest that S. aureus may potentially act as the mechanistic cause, rather than merely the result of AD.

ABBREVIATIONS

AD: Atopic dermatitis; SC: Stratum Corneum; AMP: Antimicrobial peptide; DIW: Deionized water; PDMS: Polydimethylsiloxane; GFP: Green fluorescent protein; BHI: Brain heart infusion medium.

Evaluating patient-perceived control of atopic dermatitis: design, validation, and scoring of the Atopic Dermatitis Control Tool (ADCT)

Objectives: The Atopic Dermatitis Control Tool (ADCT) was designed to evaluate patient-perceived AD control and facilitate patient-physician discussion on long-term disease control.Methods: The study was performed in adult patients with AD. Development of the ADCT followed US Food and Drug Administration (FDA) guidelines on patient-reported outcome measures (PROMs). Qualitative research, including targeted literature review, interviews with clinical experts, and combined concept elicitation/cognitive debriefing with patients with AD, was conducted to provide a list of comprehensive concepts capturing AD control per physician and patient perspectives. Quantitative methods assessed psychometric properties of the instrument and defined the threshold for AD control.Results: The resulting pilot six-item ADCT, reflecting key concepts related to AD control, had 7-day recall and assessed symptoms and impacts on patients' everyday lives by severity and/or frequency. The ADCT showed good content validity (well understood by adult patients with AD), and quick completion time (<2 min). Psychometric analysis indicated no floor/ceiling effects for response distributions, particularly strong (r ≥ 0.80) inter-item correlations for the six ADCT items, robust construct validity (r > 0.50), and item-level discriminating ability (p < .03); this supported the derivation of a total score based on responses to all items. ADCT total score showed evidence of strong internal consistency reliability (Cronbach's alpha >0.80). A score ≥7 points was identified as an optimum threshold to identify patients whose AD is "not in control."Conclusions: No single validated instrument has been available to holistically evaluate patient-perceived AD control. The newly developed ADCT displays good-to-excellent content validity, construct validity, internal consistency, reliability, and discriminating ability.

Base and Covariate Population Pharmacokinetic Analyses of Dupilumab Using Phase 3 Data

Population pharmacokinetic base and covariate models were developed to study functional dupilumab for regulatory submissions, using data from healthy volunteers and patients with moderate‐to‐severe atopic dermatitis (AD) receiving intravenous or subcutaneous doses. Sixteen studies were pooled (N = 2115; 202 healthy volunteers, 1913 AD patients). The best model was a 2‐compartment model with linear and Michaelis‐Menten elimination and 3 transit compartments describing absorption. A stepwise approach to model building, with some parameters estimated using mostly rich data and subsequently fixed, was used to avoid adverse effects of sparse data and a steep target‐mediated phase on pharmacokinetic parameters, which require rich sampling for proper estimation. Parameterization of models in terms of rates was a useful alternative to the parameterization in terms of clearances, allowing for a reduced number of covariates while providing accurate predictions. While antidrug antibodies, albumin, race, body mass index, and Eczema Area and Severity Index score were statistically significant covariates, only body weight had a notable effect on central volume, explaining interindividual variability. The model adequately described dupilumab pharmacokinetics in phase 3 trials.

Effect of Hataedock Treatment on Epidermal Structure Maintenance through Intervention in the Endocannabinoid System

The aim of this study was to investigate the efficacy of Hataedock (HTD) on skin barrier maintenance through the endocannabinoid system (ECS) intervention in Dermatophagoides farinae-induced atopic dermatitis (AD) NC/Nga mice. Douchi (fermented Glycine max Merr.) extracts prepared for HTD were orally administered to NC/Nga mice at a 20 mg/kg dose. Then, Dermatophagoides farinae extract (DfE) was applied to induce AD-like skin lesions during the 4th-6th and 8th-10th weeks. Changes in the epidermal structure of the mice were observed by histochemistry, immunohistochemistry, and TUNEL assay. The results showed that HTD significantly reduced the clinical scores (p < 0.01) and effectively alleviated the histological features. In the experimental groups, increased expression of cannabinoid receptor type (CB) 1, CB2, and G protein-coupled receptor 55 (GPR55) and distribution of filaggrin, involucrin, loricrin, and longevity assurance homolog 2 (Lass2) indicated that HTD maintained the epidermal barrier through intervening in the ECS. The expression of E-cadherin and glutathione peroxidase 4 (GPx4) was increased, and the levels of cluster of differentiation 1a (CD1A) were low. Moreover, the apoptosis of inflammatory cells was elevated. The production of phosphorylated extracellular signal-related kinase (p-ERK), phosphorylated c-Jun amino-terminal kinase (p-JNK), and phosphorylated mammalian target of rapamycin (p-mTOR) was low, and epidermal thickness was decreased. Besides, the expression levels of involucrin were measured by treating genistein, an active ingredient of Douchi extract, and palmitoylethanolamide (PEA), one of the ECS agonists. The results showed that genistein had a better lipid barrier formation effect than PEA. In conclusion, HTD alleviates the symptoms of AD by maintaining skin homeostasis, improving skin barrier formation, and downregulating inflammation, through ECS intervention.

House dust mite allergens induce interleukin 33 (IL-33) synthesis and release from keratinocytes via ATP-mediated extracellular signaling

In atopic diseases, the epithelium releases cytokines and chemokines that initiate skin inflammation. Atopic dermatitis (AD) is characterized by a disrupted epidermal barrier and is triggered or exacerbated by environmental stimuli such as house dust mite (HDM) allergens. The proinflammatory cytokine interleukin 33 (IL-33) plays an important role in the pathogenesis of AD, but how IL-33 production in keratinocytes is elicited by HDM is unknown. To that end, here we stimulated monolayer-cultured human keratinocytes and human living skin equivalents with Dermatophagoides pteronyssinus HDM extract to investigate its effects on IL-33 production from keratinocytes. The HDM extract induced intracellular expression of IL-33 and modulated its processing and maturation, triggering rapid IL-33 release from keratinocytes. Group 1 HDM allergen but not group 2 HDM allergen elicited IL-33 production. An ATP assay of keratinocyte culture supernatants revealed an acute and transient accumulation of extracellular ATP immediately after the HDM extract stimulation. Using the broad-spectrum P2 antagonist suramin, the specific purinergic receptor P2Y2 (P2RY2) antagonist AR-C118925XX, and P2RY2-specific siRNA, we discovered that the HDM extract-induced IL-33 expression was mainly dependent on extracellular ATP/P2Y2 signaling mediated by transactivation of epidermal growth factor receptor, followed by activation of the ERK kinase signaling pathway. Moreover, HDM extract-induced release of 25-kDa IL-33 from the keratinocytes depended on an extracellular ATP/P2 signaling-mediated intracellular Ca²⁺ increase. Our study demonstrates the new mechanism controlling the induction and maturation of keratinocyte-produced IL-33 by HDM allergens, an innate immune process that might play a role in AD development or severity.

Inhibitory Effect of Centella asiatica Extract on DNCB-Induced Atopic Dermatitis in HaCaT Cells and BALB/c Mice

Atopic dermatitis (AD) is a chronic inflammatory skin disease caused mainly by immune dysregulation. This study explored the anti-inflammatory and immunomodulatory effects of the Centella asiatica ethanol extract (CA) on an AD-like dermal disorder. Treatment with CA inhibited the expression of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in a dose-dependent manner in inflammatory stimulated HaCaT cells by interferon-γ (IFN-γ) and TNF-α-triggered inflammation. Eight-week-old BALB/c mice treated with 2,4-dinitrochlorobenzene (DNCB) were used as a mouse model of AD. In AD induce model, we had two types treatment of CA; skin local administration (80 µg/cm², AD+CA-80) and oral administration (200 mg/kg/d, AD+CA-200). Interestingly, the CA-treated groups exhibited considerably decreased mast cell infiltration in the ear tissue. In addition, the expression of IL-6 in mast cells, as well as the expression of various pathogenic cytokines, such as TNF-α, IL-4, IL-5, IL-6, IL-10, IL-17, iNOS, COX-2, and CXCL9, was reduced in both AD+CA-80 and AD+CA-200 groups. Collectively, our data demonstrate the pharmacological role and signaling mechanism of CA in the regulation of allergic inflammation of the skin, which supports our hypothesis that CA could potentially be developed as a therapeutic agent for AD.

Handheld confocal Raman spectroscopy (CRS) for objective assessment of skin barrier function and stratification of severity in atopic dermatitis (AD) patients

BACKGROUND

We developed the first-of-its-kind handheld confocal Raman spectroscopy (CRS) system to quantify the concentration of natural moisturizing factors in the skin.

OBJECTIVE

To evaluate the feasibility of our handheld CRS system and propose a novel quantitative index to measure skin barrier function.

METHODS

This prospective study included 30 atopic dermatitis (AD) patients and 14 healthy volunteers. All AD participants were assessed using the Scoring Atopic Dermatitis (SCORAD) severity instrument, a vapometer for trans-epidermal water loss and a moisture meter for skin surface moisture. A handheld CRS operating at 785 nm laser was used to measure the biochemical constituents of the skin up to a depth of ∼100 μm. We trained a linear kernel-based support vector machine (SVM) model for eczema classification based on the water, ceramide and urocanic acid content. A novel Eczema Biochemical Index (EBI) was then formulated using the skin constituents measured from the AD participants to stage disease severity.

RESULTS

The SVM model used to classify healthy participants and AD patients obtained high cross-validated area under the curve of 0.857 and accuracy of 0.841, with high sensitivity and specificity values of 0.857 and 0.833 respectively. EBI can be used to stratify AD patients of varying severity, based on the biochemical constituents in the skin.

CONCLUSION

As compared to the standard CRS system, the handheld CRS offers higher portability and provides Raman measurements at various body regions with similar sensitivity. This suggests that a handheld CRS device could be a valuable point-of-care resource in both research and clinical use.

Conceptual Model to Illustrate the Symptom Experience and Humanistic Burden Associated With Atopic Dermatitis in Adults and Adolescents

Supplemental digital content is available in the text.

Atopic dermatitis (AD) is a pruritic or painful dermatologic disease characterized by xerosis and eczema lesions. The symptoms/signs of AD can significantly impact patients' health-related quality of life (HRQoL). This study aimed to qualitatively explore the adult and adolescent experience of AD. A targeted literature review and qualitative concept elicitation interviews with clinicians (n = 5), adult AD patients (n = 28), and adolescent AD patients (n = 20) were conducted to elicit AD signs/symptoms and HRQoL impacts experienced. Verbatim transcripts were analyzed using thematic analysis. Twenty-nine symptoms/signs of AD were reported, including pruritus, pain, erythema, and xerosis. Atopic dermatitis symptoms/signs were reported to substantially impact HRQoL. Scratching was reported to influence the experience of symptoms and HRQoL impacts. Four proximal impacts (including discomfort and sleep disturbance) were reported. Ten domains of distal impact were reported, including impacts on psychological and social functioning and activities of daily living. A conceptual model was developed to summarize these findings. This study highlights the range of symptoms and HRQoL impacts experienced by adults and adolescents with AD. To our knowledge, this study was first to explore the lived experience of AD in both adult and adolescent patients, providing valuable insight into the relatively unexplored adolescent experience of AD.

New and Emerging Topical Therapies for Psoriasis and Atopic Dermatitis

Psoriasis and atopic dermatitis represent two of the most common skin conditions seen by both primary care and specialist dermatology. The prevalence of psoriasis in North America is 2 to 4 percent, and it is estimated to cost more than $3 billion per year to treat this condition. Atopic dermatitis has an estimated 15 to 30 percent lifetime prevalence in children and an 8 to 10 percent lifetime prevalence in adults. Both diseases have a significant impact on patient quality of life, as well as associated psychological, social, and economic consequences. While systemic therapies are available for both, the majority of patients with each condition are treated with topical therapies alone, with varying degrees of efficacy and patient satisfaction. As such, there is both need and an incentive to develop new treatments for these two conditions. In this paper, we review new and emerging topical therapies for psoriasis and atopic dermatitis.

Betamethasone Treatment for Atopic Dermatitis in Gut Microbiota Transplanted Mice

Gut microbiota composition correlates strongly with essential disease parameters in the oxazolone-induced mouse model for atopic dermatitis. The phenotype of this model can be transferred to germ-free mice with a gut microbiota transplant to achieve high and low responding mice. Therefore, the production of high responding mice through gut microbiota transplantation may be seen as a tool to reduce group sizes or increase power in intervention studies by increasing effect size. We sought to determine whether high responding mice respond to a common treatment in the same way as low responding mice. We hypothesized that while high responding mice would exhibit a higher clinical score than low responding mice before treatment, the clinical parameters would be similar in both groups after betamethasone treatment. Dermatitis was induced with oxazolone in barrier bred Swiss Webster mice, and a high responding and a low responding donor was selected based upon clinical and pathologic scores, as confirmed by monitoring a range of ear tissue cytokines. Feces from these donors were transplanted to pregnant germ-free Swiss Webster dams, and subsequently to their offspring. Although the overall effect of betamethasone on the clinical dermatitis score and ear thickness was rather small, the high responding recipients had significantly higher clinical dermatitis score and ear thickness than the low responding recipients before treatment, and these differences vanished after betamethasone treatment. We conclude that high responding recipients can be treated to a clinical level comparable with the low responding recipients.

Bacterial extracellular vesicles: A new way to decipher host-microbiota communications in inflammatory dermatoses

Bacterial extracellular vesicles (EVs) are bilayered lipid membrane structures, bearing integral proteins and able to carry diverse cargo outside the cell to distant sites. In microorganisms, EVs carry several types of molecules: proteins, glycoproteins, mRNAs and small RNA species, as mammalian EVs do, but also carbohydrates. Studying EVs opens a whole new world of possibilities to better understand the interplay between host and bacteria crosstalks, although there are still many questions to be answered in the field, especially when it comes to microbiota-derived EVs. In this review, we propose to summarize and analyse the current literature about bacterial EVs and possible clinical applications, through answering three main questions: (a) What are bacterial EVs? (b) What are EV impacts on skin inflammatory disease physiopathology? (iii) What are the possible and expected clinical applications of EVs to treat inflammatory skin diseases?

Validation of the Atopic Dermatitis Control Tool (ADCT©) using a longitudinal survey of biologic-treated patients with atopic dermatitis

BACKGROUND

The Atopic Dermatitis Control Tool (ADCT©) is a brief patient self-administered instrument designed and validated to assess atopic dermatitis (AD) control; six AD symptoms and impacts are evaluated over the past week, including overall severity of symptoms, days with intense episodes of itching, intensity of bother, problem with sleep, impact on daily activities, and impact on mood or emotions. This study assessed the reliability, validity, and responsiveness of the ADCT in a longitudinal context, and provided thresholds to identify meaningful within-person change.

METHODS

Data were from a prospective, longitudinal patient survey study of real-world effectiveness of dupilumab in patients with AD. Eligible patients completed a baseline survey before starting dupilumab and were followed at Months 1, 2, 3, and 6 post-initiation as they became eligible.

RESULTS

Psychometric analyses confirmed internal consistency; Cronbach's α coefficients were consistently above the threshold of 0.70 across each follow-up; item-to-total correlations were above the threshold of r ≥ 0.50. High correlations between the ADCT and the Dermatology Life Quality Index (DLQI) and skin pain supported construct validity, while known-group validity was shown on Patient Global Assessment of Disease (PGAD) overall well-being subgroups with worse AD-related overall well-being having higher mean ADCT total scores at all time points. The ability of the ADCT to detect change was confirmed; the threshold for meaningful within-person change was estimated to be 5 points. Finally, test-retest reliability was confirmed in subgroups of patients with stable PGAD responses.

CONCLUSIONS

Our findings confirm that the ADCT is a valid and reliable tool for assessing AD control.

Phase 1 study of crisaborole in Japanese healthy volunteers and patients with atopic dermatitis

Crisaborole ointment, 2%, is a non-steroidal phosphodiesterase 4 inhibitor for the treatment of mild to moderate atopic dermatitis (AD). This parallel-cohort, phase 1 study was conducted to investigate skin irritation potential and safety of crisaborole in healthy Japanese adults (cohort 1) and the safety and pharmacokinetic profile of crisaborole and metabolites AN7602 and AN8323 in Japanese adults with mild to moderate AD (cohort 2). In cohort 1, 20 healthy volunteers received single applications of crisaborole and vehicle simultaneously on separate locations under 48-h occlusion. In cohort 2, 12 patients with mild to moderate AD received crisaborole (n = 10) or vehicle (n = 2) twice daily for 8 days. Skin irritation and safety were assessed in cohort 1. Pharmacokinetics and safety were assessed in cohort 2. Skin irritation index (scale 0-400) was 40.0 for crisaborole and 5.0 for vehicle. No treatment-emergent adverse events (TEAE) were reported in cohort 1. The most common TEAE in the crisaborole group in cohort 2 were application site irritation (n = 7) and application site pain (n = 4). Crisaborole was rapidly absorbed, with limited systemic exposure between days 1 and 8 that was comparable with that seen in US-based participants in previous trials. Crisaborole had higher skin irritation than vehicle under occlusion in healthy Japanese adults and had an acceptable safety profile in Japanese adults with mild to moderate AD.