Obesity is linked to disease severity in moderate to severe atopic dermatitis-Data from the prospective observational TREATgermany registry.

BACKGROUND: There are conflicting data on a potential association between obesity and atopic dermatitis (AD). The purpose of this study was to investigate the relationship between obesity and AD disease severity. METHODS: Patients from the TREATgermany registry cohort were divided into three groups according to their body mass index (BMI). Due to low numbers, underweight patients (BMI <18.5 kg/m2) were excluded from the analysis. Physician- and patient-reported disease severity scores as well as additional phenotypic characteristics were evaluated for association with BMI. Generalized linear mixed models and multinomial logit models, respectively, were applied to investigate the association of BMI, age, sex and current systemic AD treatment with disease severity. RESULTS: This study encompassed 1416 patients, of which 234 (16.5%) were obese (BMI ≥30 kg/m2). Obesity was associated with lower educational background and smoking. Otherwise, obese and non-obese AD patients had similar baseline characteristics. Increased BMI was associated with higher oSCORAD (adjusted ß: 1.24, 95% CI: 1.05-1.46, p = 0.013) and Patient-oriented eczema measure (POEM) (adjusted ß: 1.09, 95% CI: 1.01-1.17, p = 0.038). However, the absolute difference in the overall oSCORAD was small between obese and non-obese AD patients (Δ oSCORAD = 2.5). Allergic comorbidity was comparable between all three groups, with the exception of asthma which was more pronounced in obese patients (p < 0.001). DISCUSSION: In this large and well-characterized AD patient cohort, obesity is significantly associated with physician- and patient-assessed measures of AD disease severity. However, the corresponding effect sizes were low and of questionable clinical relevance. The overall prevalence of obesity among the German AD patients was lower than in studies on other AD cohorts from different countries, which confirms previous research on the German population and suggests regional differences in the interdependence of AD and obesity prevalence.

High recurrence rate of eczema herpeticum in moderate/severe atopic dermatitis -TREATgermany registry analysis.

BACKGROUND: Eczema herpeticum (EH) is a disseminated skin infection caused by herpes simplex virus in atopic dermatitis (AD) patients. The frequency of EH and the clinical features of EH patients have not yet been investigated in a larger cohort. METHODS: We sought to investigate the TREATgermany cohort, a multicenter, non-interventional clinical registry of moderately to severely affected AD patients in Germany. Baseline characteristics of patients included between December 2017 and April 2021 were compared between patients without, single, and multiple EH. RESULTS: Of the 893 patients, 195 (21.8%) had at least one EH. Of the 195 patients with EH, 107 had multiple EH (54.9%), representing 12.0% of the total study population. While there were no differences in demographic characteristics, previous treatment, and disease scores at enrollment (itch, IGA, oSCORAD, EASI), patients with EH had more frequent atopic comorbidities and sensitizations to house dust mite, food, and mold. DISCUSSION: TREATgermany registry data suggest a high prevalence and recurrence rate of EH, while there appears to be no specific clinical phenotype, besides an increase in allergies, to identify EH patients in the daily routine.

Itch, sleep loss, depressive symptoms, fatigue, and productivity loss in patients with moderate-to-severe atopic dermatitis: Analyses of TREATgermany registry data.

BACKGROUND: TREATgermany is a multicenter registry including patients with moderate-to-severe atopic dermatitis (AD) from currently 74 study centers (university clinics, hospitals and practices) in Germany. As of August 31, 2021, 1,230 adult patients were enrolled. METHODS: In TREATgermany, patients and physicians fill in questionnaires pertaining to symptoms, disease severity, quality of life, depressiveness, and fatigue. In particular, limitations in work performance are assessed using the Work Limitations Questionnaire (WLQ). To assess associations between occupational performance/work limitations and symptoms, correlations and regression models were calculated. RESULTS: The examined sample of 228 employed patients reported an average of 6% at-work productivity loss within the past two weeks prior to enrolment in the registry. The WLQ productivity loss score was moderately associated with itch (r = 0.32) and sleep loss (r = 0.39) and strongly associated with depressive symptoms (r = 0.68) and fatigue (r = 0.60). CONCLUSIONS: The analyses of the registry data show that moderate-to-severe atopic dermatitis has a negative impact on the work productivity of the patients. The analyses further point out the relevant associations between work productivity, depressive symptoms, and fatigue highlighting the disease burden caused by the psychological components of AD.

Dupilumab but not cyclosporine treatment shifts the microbiome toward a healthy skin flora in patients with moderate-to-severe atopic dermatitis.

BACKGROUND: Atopic dermatitis (AD) patients display an altered skin microbiome which may not only be an indicator but also a driver of inflammation. We aimed to investigate associations among AD patients' skin microbiome, clinical data, and response to systemic therapy in patients of the TREATgermany registry. METHODS: Skin swabs of 157 patients were profiled with 16S rRNA gene amplicon sequencing before and after 3 months of treatment with dupilumab or cyclosporine. For comparison, 16s microbiome data from 258 population-based healthy controls were used. Disease severity was assessed using established instruments such as the Eczema Area and Severity Index (EASI). RESULTS: We confirmed the previously shown correlation of Staphylococcus aureus abundance and bacterial alpha diversity with AD severity as measured by EASI. Therapy with Dupilumab shifted the bacterial community toward the pattern seen in healthy controls. The relative abundance of Staphylococci and in particular S. aureus significantly decreased on both lesional and non-lesional skin, whereas the abundance of Staphylococcus hominis increased. These changes were largely independent from the degree of clinical improvement and were not observed for cyclosporine. CONCLUSIONS: Systemic treatment with dupilumab but not cyclosporine tends to restore a healthy skin microbiome largely independent of the clinical response indicating potential effects of IL-4RA blockade on the microbiome.

Itching in Atopic Dermatitis: Patient- and Physician-reported Outcomes in the German Atopic Dermatitis Registry TREATgermany.

TREATgermany is an investigator-initiated prospective disease registry. It investigates physician- and patient-reported disease severity (Eczema Area and Severity Index (EASI), objective Scoring Atopic Dermatitis (oSCORAD), Investigator Global Assessment, Patient-Oriented Eczema Measure (POEM), Patient Global Assessment (PGA)), patient-reported symptoms (itch, sleep loss, depressive symptoms), therapy courses and dermatological quality of life (DLQI) in moderate-to-severe atopic dermatitis with SCORAD > 20. 1,134 atopic dermatitis patients (mean age 41.0 ± 14.7 years, 42.5% females) were enrolled by 40 German recruiting sites (dermatological clinics and practices) between June 2016 and April 2021. The current analysis focuses on itch scores obtained with a numerical rating scale (NRS)) documented for the previous 3 days prior to baseline visit. The results show that 97.2% (1,090 of 1,121) patients experienced itch. Itch severity correlated moderately with severity of atopic dermatitis oSCORAD (rho = 0.44 (0.39-0.48)) and EASI score (rho = 0.41 (0.36-0.46)). A strong correlation was found with self-reported disease severity as PGA (rho = 0.68 (0.65-0.71)), POEM sum score (rho = 0.66 (0.63-0.69)) and dermatological quality of life impairment DLQI (rho = 0.61 (0.57-0.65)). Itch as a subjective complaint is more closely correlated with patient-reported outcomes than with objective assessments by the physician.

Sebaceous immunobiology - skin homeostasis, pathophysiology, coordination of innate immunity and inflammatory response and disease associations.

This review presents several aspects of the innovative concept of sebaceous immunobiology, which summarizes the numerous activities of the sebaceous gland including its classical physiological and pathophysiological tasks, namely sebum production and the development of seborrhea and acne. Sebaceous lipids, which represent 90% of the skin surface lipids in adolescents and adults, are markedly involved in the skin barrier function and perifollicular and dermal innate immune processes, leading to inflammatory skin diseases. Innovative experimental techniques using stem cell and sebocyte models have clarified the roles of distinct stem cells in sebaceous gland physiology and sebocyte function control mechanisms. The sebaceous gland represents an integral part of the pilosebaceous unit and its status is connected to hair follicle morphogenesis. Interestingly, professional inflammatory cells contribute to sebocyte differentiation and homeostasis, whereas the regulation of sebaceous gland function by immune cells is antigen-independent. Inflammation is involved in the very earliest differentiation changes of the pilosebaceous unit in acne. Sebocytes behave as potent immune regulators, integrating into the innate immune responses of the skin. Expressing inflammatory mediators, sebocytes also contribute to the polarization of cutaneous T cells towards the Th17 phenotype. In addition, the immune response of the perifollicular infiltrate depends on factors produced by the sebaceous glands, mostly sebaceous lipids. Human sebocytes in vitro express functional pattern recognition receptors, which are likely to interact with bacteria in acne pathogenesis. Sex steroids, peroxisome proliferator-activated receptor ligands, neuropeptides, endocannabinoids and a selective apoptotic process contribute to a complex regulation of sebocyte-induced immunological reaction in numerous acquired and congenital skin diseases, including hair diseases and atopic dermatitis.

Real-world data on the effectiveness, safety and drug survival of dupilumab: an analysis from the TREATgermany registry.

This interim analysis from the atopic dermatitis registry TREATgermany shows robust long-term efficacy, favourable safety and high persistence of dupilumab under real life conditions.

Fibrotic enzymes modulate wound-induced skin tumorigenesis.

Fibroblasts are a major component of the microenvironment of most solid tumours. Recent research elucidated a large heterogeneity and plasticity of activated fibroblasts, indicating that their role in cancer initiation, growth and metastasis is complex and context-dependent. Here, we performed genome-wide expression analysis comparing fibroblasts in normal, inflammatory and tumour-associated skin. Cancer-associated fibroblasts (CAFs) exhibit a fibrotic gene signature in wound-induced tumours, demonstrating persistent extracellular matrix (ECM) remodelling within these tumours. A top upregulated gene in mouse CAFs encodes for PRSS35, a protease capable of collagen remodelling. In human skin, we observed PRSS35 expression uniquely in the stroma of high-grade squamous cell carcinomas. Ablation of PRSS35 in mouse models of wound- or chemically-induced tumorigenesis resulted in aberrant collagen composition in the ECM and increased tumour incidence. Our results indicate that fibrotic enzymes expressed by CAFs can regulate squamous tumour initiation by remodelling the ECM.

Contribution of GATA6 to homeostasis of the human upper pilosebaceous unit and acne pathogenesis.

Although acne is the most common human inflammatory skin disease, its pathogenic mechanisms remain incompletely understood. Here we show that GATA6, which is expressed in the upper pilosebaceous unit of normal human skin, is down-regulated in acne. GATA6 controls keratinocyte proliferation and differentiation to prevent hyperkeratinisation of the infundibulum, which is the primary pathological event in acne. When overexpressed in immortalised human sebocytes, GATA6 triggers a junctional zone and sebaceous differentiation program whilst limiting lipid production and cell proliferation. It modulates the immunological repertoire of sebocytes, notably by upregulating PD-L1 and IL10. GATA6 expression contributes to the therapeutic effect of retinoic acid, the main treatment for acne. In a human sebaceous organoid model GATA6-mediated down-regulation of the infundibular differentiation program is mediated by induction of TGFß signalling. We conclude that GATA6 is involved in regulation of the upper pilosebaceous unit and may be an actionable target in the treatment of acne.

Skin microbiome modulation induced by probiotic solutions.

BACKGROUND: The skin is colonized by a large number of microorganisms, most of which are beneficial or harmless. However, disease states of skin have specific microbiome compositions that are different from those of healthy skin. Gut microbiome modulation through fecal transplant has been proven as a valid therapeutic strategy in diseases such as Clostridium difficile infections. Therefore, techniques to modulate the skin microbiome composition may become an interesting therapeutic option in diseases affecting the skin such as psoriasis or acne vulgaris. METHODS: Here, we have used mixtures of different skin microbiome components to alter the composition of recipient skin microbiomes. RESULTS: We show that after sequential applications of a donor microbiome, the recipient microbiome becomes more similar to the donor. After intervention, an initial week-long phase is characterized by the dominance of donor strains. The level of engraftment depends on the composition of the recipient and donor microbiomes, and the applied bacterial load. We observed higher engraftment using a multi-strain donor solution with recipient skin rich in Cutibacterium acnes subtype H1 and Leifsonia. CONCLUSIONS: We have demonstrated the use of living bacteria to modulate skin microbiome composition.

Expression of Potential Dermal Progenitor Cell Markers in the Tumour and Stroma of Skin Adnexal Malignant and Benign Tumours.

Stem cells are multipotent cells that maintain the skin epidermis including skin appendages such as hair follicle, sebaceous glands, and sweat glands. There is evidence that reciprocal signalling between the epidermis and the dermis plays an important role in skin development, homeostasis, wound repair, and skin cancer. The origin of skin cancer that derive from skin appendages is still controversial, including basal cell carcinoma and even more of rare tumours such as sebaceous carcinomas and whether those tumours originate from resident tissue stem cells. To investigate whether markers reported to label dermal progenitor cells are preserved in the tumour including the tumour stroma of skin adnexal tumours, we tested 45 human basal cell carcinomas, including superficial, nodular, adenoid, infiltrating, and sclerosing types, and further 38 human tumours of skin appendages including 13 sebaceous adenomas and carcinomas, 20 eccrine sweat gland tumours, and 5 pilomatricomas, syringomas, and hair follicle tumours for the expression of the potential dermal and epidermal cell markers CRABP1, Nestin, and Ephrin B2 and compared these findings with healthy, age-related human epidermis. We detected that CRABP1, Nestin, and Ephrin B2 are expressed in the intratumoural stroma as well as the tumour invasive front of skin tumours of appendages and BCCs.

Skin microdialysis: methods, applications and future opportunities-an EAACI position paper.

Skin microdialysis (SMD) is a versatile sampling technique that can be used to recover soluble endogenous and exogenous molecules from the extracellular compartment of human skin. Due to its minimally invasive character, SMD can be applied in both clinical and preclinical settings. Despite being available since the 1990s, the technique has still not reached its full potential use as a tool to explore pathophysiological mechanisms of allergic and inflammatory reactions in the skin. Therefore, an EAACI Task Force on SMD was formed to disseminate knowledge about the technique and its many applications. This position paper from the task force provides an overview of the current use of SMD in the investigation of the pathogenesis of chronic inflammatory skin diseases, such as atopic dermatitis, chronic urticaria, psoriasis, and in studies of cutaneous events during type 1 hypersensitivity reactions. Furthermore, this paper covers drug hypersensitivity, UVB-induced- and neurogenic inflammation, and drug penetration investigated by SMD. The aim of this paper is to encourage the use of SMD and to make the technique easily accessible by providing an overview of methodology and applications, supported by standardized operating procedures for SMD in vivo and ex vivo.

Mutant Lef1 controls Gata6 in sebaceous gland development and cancer.

Mutations in Lef1 occur in human and mouse sebaceous gland (SG) tumors, but their contribution to carcinogenesis remains unclear. Since Gata6 controls lineage identity in SG, we investigated the link between these two transcription factors. Here, we show that Gata6 is a ß-catenin-independent transcriptional target of mutant Lef1. During epidermal development, Gata6 is expressed in a subset of Sox9-positive Lef1-negative hair follicle progenitors that give rise to the upper SG Overexpression of Gata6 by in utero lentiviral injection is sufficient to induce ectopic sebaceous gland elements. In mice overexpressing mutant Lef1, Gata6 ablation increases the total number of skin tumors yet decreases the proportion of SG tumors. The increased tumor burden correlates with impaired DNA mismatch repair and decreased expression of Mlh1 and Msh2 genes, defects frequently observed in human sebaceous neoplasia. Gata6 specifically marks human SG tumors and also defines tumors with elements of sebaceous differentiation, including a subset of basal cell carcinomas. Our findings reveal that Gata6 controls sebaceous gland development and cancer.

Cytokine and Chemokine Recovery Is Increased by Colloid Perfusates during Dermal Microdialysis.

Cytokines and chemokines play important roles in cell signalling, and microdialysis is a promising tool for monitoring these inflammation markers ex vivo. Therefore, the collecting of these mediators at the highest concentrations possible is crucial. Depending on the size of the mediator of interest, the collection of these high molecular mass molecules has thus far been difficult due to their low recovery, even when using high cut-off (100 kDa) microdialysis membranes. This study aimed to optimize the recovery of various cytokines and chemokines by validating the use of different perfusates in cutaneous microdialysis, and comparing intravenous (i.v.) colloids, crystalloids, and a lipid emulsion formulations that are approved for i.v. METHODS: In vitro and in vivo recovery experiments using six recombinant cytokines varying in molecular size (interleukin-2 (15 kDa), interleukin-6 (20.5 kDa), interleukin-8 (8 kDa), interleukin-12p70 (70 kDa), TNF-α (17.5 kDa), and vascular endothelial growth factor (VEGF) (38 kDa)) were performed in the presence of different perfusates for i.v. APPLICATIONS: Ringer’s lactate, dextran 60 kDa, hydroxyethyl starch 70 kDa, and hydroxyethyl starch 200 kDa solutions as well as a lipid emulsion formulation. Recovery was determined through (i) microdialysis of cytokines and chemokines in Ringer’s lactate solution or human serum in vitro, and (ii) retrodialysis of excised porcine and human skin cadavers in vitro and porcine skin in vivo. Furthermore, we used skin trauma (catheter insertion) and Ultraviolet B irradiation of 3 × 3 cm² skin areas to sample cytokines and chemokines in vivo and compared the amounts that were obtained using crystalloid and colloid perfusates. All the cytokines and chemokines within the dialysates were quantified through a flow cytometry-based bead array assay. RESULTS: Overall, recovery was strongly increased by the colloids, particularly hydroxyethyl starch 70 kDa, in vitro, ex vivo, and in vivo. When compared with the recovery achieved using Ringer’s lactate, this increase was most effective for proteins ranging from 8 to 20.5 kDa. Hydroxyethyl starch 70 kDa significantly increased the recovery of interleukin (IL)-8 in human serum in vitro when compared with Ringer’s lactate. More cytokines and chemokines were recovered using colloids compared with crystalloids. However, the increase in recovery values was lower for IL-12p70 and VEGF. CONCLUSIONS: Regarding the dialysate volumes and final dialysate concentrations, colloid perfusates are overall superior to crystalloid perfusates, such as Ringer’s lactate, when sampling cytokines and chemokines, resulting in higher recoveries. However, the sampling of high-molecular-mass cytokines during microdialysis remains challenging, and experimental in vitro data are not completely comparable with data obtained ex vivo or in vivo.

Eczema in Psoriatico: An Important Differential Diagnosis Between Chronic Allergic Contact Dermatitis and Psoriasis in Palmoplantar Localization.

Differential diagnosis of palmoplantar non-pustular psoriasis and chronic allergic contact dermatitis (ACD) and the combination of these conditions, termed "eczema in psoriatico" (EIP), is difficult, especially in cases of isolated involvement. A blind re-evaluation of 63 archived formalin-fixed palmoplantar samples, previously diagnosed clinically as either psoriasis or chronic ACD, was performed. Samples were allocated to histopathological diagnoses of psoriasis, contact dermatitis or EIP. Immunohistological stainings were performed for better characterization. Immunochemistry of EIP revealed features that overlapped contemporarily with psoriasis (cytokeratin 17 (CK17), Ki67, interleukin (IL)-8, IL-17, IL-23) and with ACD (CD1a, major histocompatibility complex (MHC) class I, MHC class II, epidermal T-cell subsets). Surprisingly, a significantly much higher number of dermal CD8+ T cells was found in EIP than in ACD and psoriasis. In conclusion, this study provides insight into the immunohistological differentiation of palmoplantar psoriasis, chronic ACD and EIP.