Single-cell RNA sequencing reveals 2D cytokine assay can model atopic dermatitis more accurately than immune-competent 3D setup.

Modelling atopic dermatitis (AD) in vitro is paramount to understand the disease pathophysiology and identify novel treatments. Previous studies have shown that the Th2 cytokines IL-4 and IL-13 induce AD-like features in keratinocytes in vitro. However, it has not been systematically researched whether the addition of Th2 cells, their supernatants or a 3D structure is superior to model AD compared to simple 2D cell culture with cytokines. For the first time, we investigated what in vitro option most closely resembles the disease in vivo based on single-cell RNA sequencing data (scRNA-seq) obtained from skin biopsies in a clinical study and published datasets of healthy and AD donors. In vitro models were generated with primary fibroblasts and keratinocytes, subjected to cytokine treatment or Th2 cell cocultures in 2D/3D. Gene expression changes were assessed using qPCR and Multiplex Immunoassays. Of all cytokines tested, incubation of keratinocytes and fibroblasts with IL-4 and IL-13 induced the closest in vivo-like AD phenotype which was observed in the scRNA-seq data. Addition of Th2 cells to fibroblasts failed to model AD due to the downregulation of ECM-associated genes such as POSTN. While keratinocytes cultured in 3D showed better stratification than in 2D, changes induced with AD triggers did not better resemble AD keratinocyte subtypes observed in vivo. Taken together, our comprehensive study shows that the simple model using IL-4 or IL-13 in 2D most accurately models AD in fibroblasts and keratinocytes in vitro, which may aid the discovery of novel treatment options.

Hand eczema symptoms, exposures and skin care in orthodontics : A national, cross-sectional questionnaire-based survey.

OBJECTIVES: Occupational hand eczema is a common inflammatory skin condition among healthcare professionals. Orthodontists are frequently exposed to a variety of irritating and allergenic substances, and therefore they belong to a predisposed group to develop hand eczema. However, current data on the prevalence and predisposing factors among orthodontists to provide adequate prophylaxis are lacking. METHODS: An anonymous online survey was conducted in Germany between January and February 2023 and distributed to 2402 orthodontists. The questionnaire addressed general information on current skin status, as well as occupational skin exposure and skin care. RESULTS: A total of 209 orthodontists responded to the survey. Seventy-four percent reported experiencing hand eczema-specific symptoms within the last 12 months, with 24% describing moderate and 10% describing severe symptoms. The average daily glove wearing time was stated to be 6 ± 2 h. The most frequently reported triggers at work were frequent hand washing (62.7%) and hand disinfection (59.1%). Among all the respondents, 22.6% stated not using either barrier cream or moisturizer. CONCLUSIONS: This study showed a high prevalence of hand eczema symptoms among orthodontists, which is probably due to frequent disinfection, hand washing, and contact with allergens such as acrylates. In this professional group especially, against a background of future increasing acrylate and epoxy resin exposures due to in-office three-dimensional printing processes, timely education and skin protection could decisively counteract the pathogenesis of hand eczema.

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.

Symptom severity reflected by NYHA grade is independently associated with pruritus in chronic heart failure patients.

BACKGROUND: Pruritus is a symptom profoundly impairing patients' quality of life (QoL). It is a common symptom in chronic heart failure (CHF) patients of yet unknown nature. The aim of this study was to evaluate the risk factors of pruritus in CHF patients. METHODS: For this monocentric, prospective cohort study, CHF patients were recruited and CHF symptoms, comorbidities and drug intake were assessed using a structured report. Additionally, a questionnaire evaluated pruritus symptoms. Detailed medical histories including laboratory test results were retrieved from patient files for all participants. RESULTS: We evaluated data from 550 CHF patients. Of those, 25.3% reported pruritus to occur frequently (3-5 times per week), often (1-2 times per week) or daily. Patients of higher NYHA classes (NYHA III + IV) experienced significantly more pruritus (31.2%) than lower NYHA classes (NYHA I + II) (21.1%, p = 0.024). Patients with pruritus reported disproportionately often concomitant stasis dermatitis (p = 0.026) and chronic lung disease (p = 0.014). Other parameters reflecting cardiac, liver, kidney and thyroid function, as well as medical therapies showed no significant differences between patients with and without pruritus. In the multivariate logistic regression analysis, only NYHA class (p = 0.016, OR 1.55, 95% confidence interval (CI): [1.09; 2.20]) and elevated leukocyte count (p = 0.007, OR 1.11, CI [1.03; 1.21]) remained significantly associated with pruritus in CHF patients. CONCLUSIONS: NYHA class is an independent predictor for pruritus in CHF patients. Besides NYHA class, leukocyte count was also associated with increased pruritus. Pruritus may impair QoL in CHF patients and should thus be included in the assessment of those patients. We suggest that providing best care for CHF patients can be achieved through an interdisciplinary approach of cardiologists and dermatologists and should include a pruritus assessment.

Adverse Effects Under Th2 Biologics (Dupilumab and Tezepelumab) in a Patient with Severe Asthma and Atopic Dermatitis.

INTRODUCTION: This is the first report of a patient with severe asthma and atopic dermatitis that developed local perioral skin infection which onset coincided with the patient's treatment with dupilumab (candida albicans) and later with tezepelumab (microscopic detection of yeast). CASE PRESENTATION: Besides moderate headache, macular exanthema was found after administration of tezepelumab, which was subsequently accompanied by a worsening of symptoms upon reexposure to the treatment. Both sensations needed multidisciplinary treatment and both antibody therapies were stopped.

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.

The epithelial barrier: The gateway to allergic, autoimmune, and metabolic diseases and chronic neuropsychiatric conditions.

Since the 1960 s, our health has been compromised by exposure to over 350,000 newly introduced toxic substances, contributing to the current pandemic in allergic, autoimmune and metabolic diseases. The "Epithelial Barrier Theory" postulates that these diseases are exacerbated by persistent periepithelial inflammation (epithelitis) triggered by exposure to a wide range of epithelial barrier-damaging substances as well as genetic susceptibility. The epithelial barrier serves as the body's primary physical, chemical, and immunological barrier against external stimuli. A leaky epithelial barrier facilitates the translocation of the microbiome from the surface of the afflicted tissues to interepithelial and even deeper subepithelial locations. In turn, opportunistic bacterial colonization, microbiota dysbiosis, local inflammation and impaired tissue regeneration and remodelling follow. Migration of inflammatory cells to susceptible tissues contributes to damage and inflammation, initiating and aggravating many chronic inflammatory diseases. The objective of this review is to highlight and evaluate recent studies on epithelial physiology and its role in the pathogenesis of chronic diseases in light of the epithelial barrier theory.

Dupilumab strengthens herpes simplex virus type 1-specific immune responses in atopic dermatitis.

BACKGROUND: Impaired virus clearance in a subgroup of atopic dermatitis (AD) patients can lead to severe herpes simplex virus (HSV) infections called eczema herpeticum (EH). We recently identified a type 2 skewed viral immune response in EH patients. Clinical data suggest a reduced incidence of EH in AD patients treated with dupilumab, although immunologic investigations of this phenomenon are still lacking. OBJECTIVE: We examined the impact of dupilumab on the HSV type 1 (HSV-1) specific immune response in AD, focusing on patients with (ADEH+) and without (ADEH-) a history of EH. METHODS: Sera and peripheral blood mononuclear cells were collected from ADEH+ and ADEH- patients, a subgroup of whom was receiving dupilumab treatment, and healthy controls. Serum samples were tested for IgE against HSV-1 glycoprotein D (n = 85). Peripheral blood mononuclear cells were stimulated with HSV peptides, and activated CD4+ and CD8+ cells were characterized by flow cytometry after magnetic enrichment via CD154 or CD137 (n = 60). Cytokine production of HSV-1-reactive T-cell lines (n = 33) and MHC-I tetramer+ (HSV-1-UL25) CD8+ T cells was investigated by bead assay and intracellular cytokine staining (n = 21). RESULTS: We confirmed that HSV-1-specific IgE is elevated in ADEH+ patients. During dupilumab treatment, the IgE levels were significantly decreased, reaching levels of healthy controls. HSV-1-specific TC1 frequencies were elevated in ADEH- patients treated with dupilumab compared to dupilumab-negative patients. There were no changes in the frequencies of HSV-1-specific TH cells while receiving dupilumab therapy. AD patients receiving dupilumab exhibited elevated IFN-γ and reduced IL-4 production in HSV-1-UL25-epitope-specific T cells compared to dupilumab-negative patients. CONCLUSION: Dupilumab may improve the HSV-1-specific immune response in AD as a result of an increased type I immune response and a reduction of HSV-1-specific IgE.

Dupilumab-induced eosinophilia in patients with diffuse type 2 chronic rhinosinusitis.

BACKGROUND: Dupilumab, a monoclonal anti-IL-4Rα antibody, is approved for several type 2 mediated inflammatory diseases like asthma, atopic dermatitis, and diffuse type 2 chronic rhinosinusitis (CRS). Clinical studies had reported a transient increase in blood eosinophils during dupilumab therapy. This study aimed to assess the impact of elevated blood eosinophils on clinical outcome and to investigate the cause of high blood eosinophil levels under dupilumab therapy. METHODS: Patients suffering from diffuse type 2 CRS treated with dupilumab were examined on days 0, 28, 90, and 180 after therapy start. Sino-Nasal-Outcome-Test Score (SNOT-22), Total Nasal Polyp Score (TNPS), and blood samples were collected. Cytokine measurements and proteomics analysis were conducted. Flow cytometry analysis measured receptor expression on eosinophils. RESULTS: Sixty-eighty patients were included. Baseline eosinophilia ≥0.3G/L was observed in 63.2% of patients, and in 30.9% of patients, eosinophils increased by ≥0.5G/L under dupilumab. Subjects with eosinophilia ≥0.3G/L at baseline had the best SNOT-22 mean change compared to no eosinophilia. Eosinophil elevation during dupilumab therapy had no impact on clinical scores. The eosinophil adhesion molecule VCAM-1 decreased significantly during therapy in all patients. The chemokine receptor CXCR4 was significantly down- and IL-4 upregulated in subjects with eosinophil increase. CONCLUSION: Our findings suggest that increased eosinophils in type 2 CRS are associated with a good clinical response to dupilumab. Patients with elevated IL-4 at baseline developed dupilumab-induced transient eosinophilia. We identified the downregulation of VCAM-1 and surface markers CD49d and CXCR4 on eosinophils as possible explanations of dupilumab-induced eosinophilia.

[Eczema and its treatment in older adults]. / Altersekzeme und deren Therapie.

Eczema encompass a wide range of dermatoses that can affect elderly patients in particular. Common differential diagnoses in elderly patients include asteatotic eczema, late-onset atopic dermatitis, allergic contact dermatitis, early phases of mycosis fungoides, eczematous and pruriginous variants of premonitory bullous pemphigoid, as well as eczematized scabies and post-scabietic eczema. Given the partly overlapping clinical presentations, accurate diagnosis plays a crucial role in the management of these conditions. Therapeutic options depend on the underlying disease and necessitate an individualized approach. This review presents relevant types of eczema in older adults together with diagnostic and therapeutic approaches. In addition to confirming the diagnosis and selecting the appropriate treatment, aspects relevant to the care of older patients should be incorporated into the tailored therapeutic approach.

Current situation of allergological health care at German hospitals.

BACKGROUND: Allergic medical care in Germany is organized on an interdisciplinary basis. An overview of the current care situation is necessary to manage and improve interdisciplinary cooperation. METHODS: Between January and February 2022, questionnaires were sent online and by mail to chief physicians of inpatient clinical departments to which most allergological diseases are assigned (dermatology, otorhinolaryngology [ENT], pulmonology, pediatrics, environmental/occupational medicine, gastroenterology; n = 899). RESULTS: The response rate was 52.1%. Allergology departments of dermatology, ENT and pulmonology were predominantly located in metropolitan areas (> 100,000 inhabitants), whereas responses of pediatric departments were mostly from smaller towns. 76.8% of the respondents reported existing interdisciplinary treatment plans with other specialties. Pediatric and pulmonology clinics stated disproportionately few interdisciplinary treatment concepts with dermatology and ENT clinics, especially in smaller cities with < 100,000 inhabitants. Diagnosis and therapy of allergic rhinitis were performed in particular by the departments of ENT, asthma mainly by the pulmonology departments. Care of other allergological diseases was most frequently reported by chief physicians of dermatology and pediatrics. CONCLUSIONS: In metropolitan areas, participating departments provide allergology care in a cooperative manner. A large spectrum of care is covered in cooperation with dermatological clinics. In more rural areas, cooperation is rarer; here, mainly pediatric departments provide allergological care, which may explain the more limited range of services compared to metropolitan areas.

Skin Tests versus Serology: Specific IgE May Suffice for Diagnosis of Vespid Venom Allergy and Follow-Up of Allergen Immunotherapy.

INTRODUCTION: In adults, allergic reactions to insect stings are among the most frequent causes of anaphylaxis, a potentially life-threatening condition. Recurrent anaphylaxis following vespid stings may be prevented by allergen immunotherapy (AIT). The aim of this study was to evaluate the benefit of measuring venom-induced wheal area in intracutaneous skin tests (ICT), in comparison to various serological and clinical parameters, for the diagnosis of severe vespid venom allergy and during follow-up of AIT. METHODS: We conducted a monocentric, retrospective evaluation of 170 patients undergoing AIT against vespid venoms. We scanned ICT wheals at baseline and at three time points after AIT initiation and measured wheal area using objective data analysis software. RESULTS: We found that ICT histamine-induced and venom-induced wheal areas did not correlate. In addition, the venom-induced wheal area was independent from the minimal venom concentration required to elicit a wheal in an ICT and all other parameters. No correlation was found between wheal area and the severity of anaphylaxis. Wheal area standardized to the application of 0.1 µg/mL venom inversely correlated with anaphylaxis severity and positively correlated with venom-specific IgE levels. During AIT, mean areas of venom-induced wheals did not change. In contrast, venom-specific IgG and IgG4 levels, and the minimal venom concentration required to induce a positive ICT result increased, while the venom wheal area standardized to 0.1 µg/mL venom application and specific IgE levels decreased over time. CONCLUSION: Wheal area evaluation did not provide additional information over specific IgE analysis. We therefore recommend that ICTs are used only as a secondary measure for confirming serological test results.

Limited Reimbursement and Underuse of Digital Healthcare Concepts Are Major Barriers to Clinical Allergological Care in Germany.

INTRODUCTION: Allergic diseases represent a broad spectrum of high-prevalence, chronic conditions that remain underdiagnosed and undertreated. The aims of this interdisciplinary, questionnaire-based, non-interventional study were to identify and analyze potential barriers to clinical allergological care in Germany. METHODS: All hospitals listed in the German hospital register involved in the treatment of allergological patients (n = 899) were invited to participate. The study yielded a response rate of 52.1% (n = 468). RESULTS: Overall, 88.5% of clinics agreed that allergological care in Germany needs improvement, especially in terms of reimbursement for diagnostics and therapy. More than 80% of participating clinics reported that the decreased availability of test substances and the time-intensity of allergological testing represent relevant barriers. For dermatology and pulmonology, the former is the strongest barrier, while for pediatric and ENT clinics, time-intensity is regarded as the strongest barrier. The availability of good therapy and appropriate guidelines present no barriers to allergological care. Regarding the use of digital healthcare concepts, a very large majority of clinics (n = 352; 91.4%) do not offer video consultations or the use of health applications in patient care. CONCLUSION: In conclusion, we have identified several structural barriers to allergological care in Germany. Reimbursement and the use of digital healthcare concepts in German clinics providing allergological care need improvement. Based on the results of this study, there is an urgent need for researchers and policymakers to further investigate and support allergology departments in their clinical work and in their implementation of digital healthcare concepts.

Prospective, monocentric, observational study of the long-term effectiveness of omalizumab in chronic urticaria.

Omalizumab, a monoclonal antibody targeting IgE, has been approved in 2014 for the treatment of H1 antihistamine-refractory chronic urticaria. Data on long-term effectiveness and predictive factors for treatment response are currently limited. In this monocentric, prospective, observational study, 112 patients with chronic spontaneous urticaria (CSU) and 32 patients with chronic inducible urticaria (CIndU) were included. In addition to a rapid response, omalizumab also showed good effectiveness on both forms of chronic urticaria over 2 years. Low total IgE and elevated Yersinia IgA were identified as potential predictive markers for slower treatment responses in CSU. In conclusion, the present study highlights the efficacy of omalizumab for the treatment of chronic urticaria. With emerging new therapeutic options for chronic urticaria, further genetic as well as molecular markers are needed to establish patient-specific therapy selection.

Specific IgE against the house dust mite allergens Der p 5, 20 and 21 influences the phenotype and severity of atopic diseases.

BACKGROUND: House dust mites (HDM) are among the most important sources for airborne allergens with high relevance for atopic diseases. Routine tests contain only 4 of 32 registered allergens of Dermatophagoides pteronyssinus. Clinical relevance and pathomechanistic properties of many allergens are not well understood. OBJECTIVE: The association of several HDM allergens with allergic rhinitis, allergic asthma, and atopic dermatitis was investigated to identify allergens with biomarker potential and to transfer them into diagnostics. METHODS: Eight out of nine D. pteronyssinus allergens (nDer p 1, rDer p 2, rDer p 5, rDer p 7, rDer p 10, rDer p 13, rDer p 20, rDer p 21, rDer p 23) were recombinantly expressed and purified. Sensitization patterns of 384 HDM-allergic individuals exhibiting different clinical phenotypes were analyzed with a serum-saving multiplex array. RESULTS: Sensitization to more than three mite allergens (sensitization count) was associated with allergic asthma and/or atopic dermatitis. Reactions to Der p 5 and Der p 21 were more frequent in allergic asthma compared to allergic rhinitis. Atopic dermatitis patients were more often sensitized to Der p 5, Der p 20, and Der p 21 among others. Der p 20-IgE > 80 kU/L was associated with severe atopic dermatitis in 75% of patients. CONCLUSION: This study demonstrates the clinical importance of the sensitization count and of certain allergens (Der p 5, Der p 20, and Der p 21) not available for routine diagnostics yet. Implementing them as well as the sensitization count in diagnostic measures will improve diagnosis and risk assessment of HDM-allergic patients.

Intravenous immunoglobulins, cyclosporine, and best supportive care in epidermal necrolysis: Diverse effects on systemic inflammation.

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare but potentially life-threatening cutaneous adverse reactions. There is still no consensus on adjuvant treatments, and little is known about their effects on systemic inflammation in SJS/TEN. Our aim was to characterize the systemic and cutaneous immune profiles of SJS/TEN patients and to investigate whether/how intravenous immunoglobulins (IVIG), cyclosporine A (CSA), and best supportive care only (BSCO) affected the systemic immune signature and clinical outcome (6 week-mortality, complications, hospitalization stay). METHODS: We included 16 patients with SJS/TEN, treated with high-dose IVIG (n = 8), CSA (n = 4) or BSCO (n = 4). Serial serum samples were obtained prior-, 5-7 days, and 21 days after treatment onset. Serum levels of inflammation-/immune response-associated proteins were measured by high-throughput proteomics assay (OLINK) and cytotoxic molecules by ELISA. RNA extracted from skin biopsies collected prior treatment was analyzed by Nanostring. RESULTS: Serum inflammatory profiles in SJS/TEN patients were notably characterized by massive upregulation of type 1 immune response and proinflammatory markers. Surprisingly, there was limited overlap between cutaneous and serum immune profiles. Serial serological measurements of immune response markers showed very diverse dynamics between the different treatment groups. IVIG-treated patients showed completely different dynamics and most significant proteomic changes in an early phase (Day 5-7). In all treatment groups, type 1-/inflammatory response markers were dampened at day 21. Clinically, there were no outcome differences. CONCLUSION: Our study demonstrates that BSCO, CSA, and IVIG have very diverse biological effects on the systemic inflammatory response in SJS/TEN, which may not correlate with clinical outcome differences.