Raster-scanning optoacoustic mesoscopy biomarkers for atopic dermatitis skin lesions.

Atopic dermatitis (AD) is the most common chronic inflammatory skin disease worldwide. Its severity is assessed using scores that rely on visual observation of the affected body surface area, the morphology of the lesions and subjective symptoms, like pruritus or insomnia. Ideally, such scores should be complemented by objective and accurate measurements of disease severity to standardize disease scoring in routine care and clinical trials. Recently, it was shown that raster-scanning optoacoustic mesoscopy (RSOM) can provide detailed three-dimensional images of skin inflammation processes that capture the most relevant features of their pathology. Moreover, precise RSOM biomarkers of inflammation have been identified for psoriasis. However, the objectivity and validity of such biomarkers in repeated measurements have not yet been assessed for AD. Here, we report the results of a study on the repeatability of RSOM inflammation biomarkers in AD to estimate their precision. Optoacoustic imaging analysis revealed morphological inflammation biomarkers with precision well beyond standard clinical severity metrics. Our findings suggest that optoacoustic mesoscopy may be a good choice for quantitative evaluations of AD that are inaccessible by other methods. This could potentially enable the optimization of disease scoring and drug development.

Continued treatment with secukinumab is associated with high retention or regain of response.

BACKGROUND: Conventional analyses present aggregate data, masking late responders and efficacy reductions. Secukinumab, a fully human monoclonal antibody that selectively neutralizes interleukin (IL)-17A, shows sustained efficacy in moderate-to-severe psoriasis. OBJECTIVES: To determine stability of response to secukinumab, changes in efficacy were assessed in individual patients. METHODS: This is a post hoc analysis of two phase III randomized controlled trials, FIXTURE (trial registration: NCT01358578) and CLEAR (trial registration: NCT02074982). Patients received secukinumab 300 mg (FIXTURE and CLEAR), etanercept 50 mg (FIXTURE) or ustekinumab 45 or 90 mg (CLEAR) over 52 weeks. Mutually exclusive response categories were defined: ≥ 90% improvement in the Psoriasis Area and Severity Index (PASI 90) ('excellent'), ≥ 75% improvement in PASI (PASI 75) and < PASI 90 ('good') and < PASI 75 ('insufficient'). Reductions in efficacy were defined as shifts from higher to lower response categories between two consecutive visits maintained for a third consecutive visit. Loss of efficacy was defined as a reduction of efficacy resulting in 'insufficient' response. All comparisons are descriptive. RESULTS: At 52 weeks, in CLEAR, 90·2% (303/336) of patients on secukinumab achieved stable efficacy without loss and 77·7% (261/336) showed stable efficacy without any reduction of response [74·3% (252/339) and 59·9% (203/339) of patients for ustekinumab]. In FIXTURE, 83·5% (273/327) and 66·4% (217/327) of patients on secukinumab had stable efficacy without loss or reduction of response [58·3% (190/326) and 42·6% (139/326) for etanercept]. Response was regained by continuing secukinumab treatment in 50% (8/16) of patients in CLEAR and 26% (9/34) in FIXTURE. Similar patterns were observed for other response definitions. CONCLUSIONS: Efficacy with secukinumab was stable over 52 weeks of treatment in most patients. Continued treatment with secukinumab resulted in regain of efficacy in some patients. Persistent loss of response was uncommon. What's already known about this topic? Secukinumab, a fully human monoclonal antibody that selectively neutralizes interleukin (IL)-17A, shows significant and sustained efficacy in the treatment of moderate-to-severe psoriasis. Secondary loss of response may be experienced by a minority of patients treated with secukinumab, as with other biologics, but the extent of this and the potential for regain of efficacy with continued treatment is not well understood. What does this study add? To determine stability of response to secukinumab and inform clinical practice, changes in efficacy were assessed at individual patient level using response categories. Efficacy with secukinumab was stable over 52 weeks of treatment in most patients, and continued treatment with secukinumab resulted in efficacy regain after loss in some patients. Persistent loss of response was uncommon. Patient factors such as body weight may affect the likelihood of loss of efficacy.

IL-17C amplifies epithelial inflammation in human psoriasis and atopic eczema.

BACKGROUND: Key pathogenic events of psoriasis and atopic eczema (AE) are misguided immune reactions of the skin. IL-17C is an epithelial-derived cytokine, whose impact on skin inflammation is unclear. OBJECTIVE: We sought to characterize the role of IL-17C in human ISD. METHODS: IL-17C gene and protein expression was assessed by immunohistochemistry and transcriptome analysis. Primary human keratinocytes were stimulated and expression of cytokines chemokines was determined by qRT-PCR and luminex assay. Neutrophil migration towards supernatant of stimulated keratinocytes was assessed. IL-17C was depleted using a new IL-17C-specific antibody (MOR106) in murine models of psoriasis (IL-23 injection model) and AE (MC903 model) as well as in human skin biopsies of psoriasis and AE. Effects on cell influx (mouse models) and gene expression (human explant cultures) were determined. RESULTS: Expression of IL-17C mRNA and protein was elevated in various ISD. We demonstrate that IL-17C potentiates the expression of innate cytokines, antimicrobial peptides (IL-36G, S100A7 and HBD2) and chemokines (CXCL8, CXCL10, CCL5 and VEGF) and the autocrine induction of IL-17C in keratinocytes. Cell-free supernatant of keratinocytes stimulated with IL-17C was strongly chemotactic for neutrophils, thus demonstrating a critical role for IL-17C in immune cell recruitment. IL-17C depletion significantly reduced cell numbers of T cells, neutrophils and eosinophils in murine models of psoriasis and AE and led to a significant downregulation of inflammatory mediators in human skin biopsies of psoriasis and AE ex vivo. CONCLUSION: IL-17C amplifies epithelial inflammation in Th2 and Th17 dominated skin inflammation and represents a promising target for the treatment of ISD.

Is the humoral immunity dispensable for the pathogenesis of psoriasis?

BACKGROUND: Imbalances of T-cell subsets are hallmarks of disease-specific inflammation in psoriasis. However, the relevance of B cells for psoriasis remains poorly investigated. OBJECTIVE: To analyse the role of B cells and immunoglobulins for the disease-specific immunology of psoriasis. METHODS: We characterized B-cell subsets and immunoglobulin levels in untreated psoriasis patients (n = 37) and compared them to healthy controls (n = 20) as well as to psoriasis patients under disease-controlling systemic treatment (n = 28). B-cell subsets were analysed following the flow cytometric gating strategy based on the surface markers CD24, CD38 and CD138. Moreover, immunofluorescence stainings were used to detect IgA in psoriatic skin. RESULTS: We found significantly increased levels of IgA in the serum of treatment-naïve psoriasis patients correlating with disease score. However, IgA was only observed in dermal vessels of skin sections. Concerning B-cell subsets, we only found a moderately positive correlation of CD138+ plasma cells with IgA levels and disease score in treatment-naïve psoriasis patients. Confirming our hypothesis that psoriasis can develop in the absence of functional humoral immunity, we investigated a patient who suffered concomitantly from both psoriasis and a hereditary common variable immune defect (CVID) characterized by a lack of B cells and immunoglobulins. We detected variants in three of the 13 described genes of CVID and a so far undescribed variant in the ligand of the TNFRSF13B receptor leading to disturbed B-cell maturation and antibody production. However, this patient showed typical psoriasis regarding clinical presentation, histology or T-cell infiltrate. Finally, in a group of psoriasis patients under systemic treatment, neither did IgA levels drop nor did plasma cells correlate with IgA levels and disease score. CONCLUSION: B-cell alterations might rather be an epiphenomenal finding in psoriasis with a clear dominance of T cells over shifts in B-cell subsets.

Assessing nailfold microvascular structure with ultra-wideband raster-scan optoacoustic mesoscopy.

Nailfold capillaroscopy, based on bright-field microscopy, is widely used to diagnose systemic sclerosis (SSc). However it cannot reveal information about venules and arterioles lying deep under the nailfold, nor can it provide detailed data about surface microvasculature when the skin around the nail is thick. These limitations reflect the fact that capillaroscopy is based on microscopy methods whose penetration depth is restricted to about 200 µm. We investigated whether ultra-wideband raster-scan optoacoustic mesoscopy (UWB-RSOM) can resolve small capillaries of the nailfold in healthy volunteers and compared the optoacoustic data to conventional capillaroscopy examinations. We quantified UWB-RSOM-resolved capillary density and capillary diameter as features that relate to SSc biomarkers, and we obtained the first three-dimensional, in vivo images of the deeper arterioles and venules. These results establish the potential of UWB-RSOM for analyzing SSc-relevant markers.

[Early detection of occupational skin diseases in sewer workers]. / Früherkennung von berufsspezifischen Hauterkrankungen bei Kanalarbeitern.

BACKGROUND: Skin diseases affect 30-70% of the world population, and globally, skin cancer rates are continuously increasing. In this respect, prevention programs and early detection of skin diseases are of particular importance. OBJECTIVES: To screen sewer workers for skin diseases with regard to their work-related risk. METHODS: Employees of the municipal utilities in Munich (Münchner Stadtentwässerung) underwent a whole-body examination of the skin, conducted by two dermatologists. In addition, all employees completed a paper-based questionnaire on risk behavior and preventive measures. RESULTS: We examined 81 employees (79 men, 2 women, mean age 45.7 ± 9.5 years). Skin lesions in need of treatment were found in 30.9% (n = 25): the most frequent diagnosis was mycosis pedis (16.1%). In addition, one employee was diagnosed with basal cell carcinoma and two with actinic keratoses. According to the questionnaire, 43.5% of the employees had undergone a physician-led skin cancer screening in the past, whereas sun-protection practices were rarely applied. CONCLUSION: According to our findings, employee skin cancer screening seems to be beneficial for the detection of work-related skin diseases and is associated with a high participation rate. Furthermore, the study suggests that sewer workers have a high rate of mycosis pedis, possibly a work-related effect.

Sebocytes contribute to skin inflammation by promoting the differentiation of T helper 17 cells.

BACKGROUND: The main function of sebocytes is considered to be the production of lipids to moisturize the skin. However, it recently became apparent that sebocytes release chemokines and cytokines and respond to proinflammatory stimuli as well as the presence of bacteria. OBJECTIVES: To analyse the functional communication between human sebocytes and T cells. METHODS: Immunofluorescence stainings for CD4 and interleukin (IL)-17 were performed on acne sections and healthy skin. Migration assays and T-cell-stimulation cultures were performed with supernatants derived from unstimulated or prestimulated SZ95 sebocytes. Dendritic cells were generated in the presence of SZ95 supernatant and subsequently used in mixed leucocyte reactions. RESULTS: We showed that CD4+ IL-17+ T cells accumulate around the pilosebaceous unit and are in close contact with sebocytes in acne lesions. By using SZ95 sebocyte supernatant, we demonstrate a chemotactic effect of sebocytes on neutrophils, monocytes and T cells in a CXCL8-dependent manner. Furthermore, sebocyte supernatant induces the differentiation of CD4+ CD45RA+ naive T cells into T helper (Th)17 cells via the secretion of IL-6, transforming growth factor-ß and, most importantly, IL-1ß. No direct effects of sebocytes on the function of CD4+ CD45RO+ memory T cells were detected. Moreover, sebocytes functionally interact with Propionibacterium acnes in the maturation of dendritic cells, leading to antigen-presenting cells that preferentially prime Th17 cells. CONCLUSIONS: Our study provides evidence that human sebocytes actively participate in inflammatory processes in the skin by recruiting and communicating with immune cells. This interaction leads to the generation of Th17 cells, which might contribute to the pathogenesis not only of acne vulgaris, but also of several inflammatory skin diseases.

Addiction: an underestimated problem in psoriasis health care.

BACKGROUND: Psoriasis is a disease of enormous socio-economic impact. Despite approval of numerous highly efficient and costly therapies, a minor proportion of severely affected patients actually receives sufficient treatment. OBJECTIVE: To investigate whether addictions are associated with psoriasis and to develop evidence-based recommendations for dermatologists in their daily clinical practice in order to improve medical assessment of psoriasis and patients' quality of life. PATIENTS AND METHODS: Psoriasis patients at the University Department of Dermatology were asked to fill out a paper-based self-reported anonymous questionnaire with 92 questions of validated screening tests for the six most common addictions in Germany (alcohol, nicotine, drugs and illegal drugs, gambling, food). Body weight and height as well as current Psoriasis Area and Severity Index (PASI) were documented as well. RESULTS: Between October 2015 and February 2016, 102 patients (65 males, 37 females; mean age 49.7 years (SD 13.4), range 18-83 years) participated in the study. Fifty-seven of the 102 patients showed addictive behaviour. Of these, 23.8% were high-risk drinkers, 41% regular smokers, 11% at risk of drug abuse, 4.1% at risk of food dependency and 19% compulsive gamblers. Compared with the general population, these results are significantly higher for alcohol abuse (P < 0.005), nicotine (P < 0.001) and gambling (P < 0.001). Body mass index was significantly higher in the study population (P < 0.001). CONCLUSION: Addictions and gambling are more prevalent in patients with psoriasis compared with the general population. Respective screening measures are recommended in daily practice for doctors treating psoriasis patients, and PeakPASI is suggested as a score to document patients' lifetime highest PASI. Parallel to new drug approvals and even more detailed insights into the pathomechanism of psoriasis, public health strategies and interdisciplinary approaches are essential for a general sustained psoriasis treatment.

Potential role of Th17 cells in the pathogenesis of type 2 autoimmune pancreatitis.

Th17 cells have been shown to play an important role in the pathogenesis of a variety of autoimmune diseases. The aim of this study was to investigate the potential role of Th17 cells in autoimmune pancreatitis (AIP). Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to determine gene expression of the signature cytokines of Th17 cells IL-17A and IL-21 and of the Th17 lineage-specific transcription factor retinoic acid receptor-related orphan receptor C (RORC) in human tissue specimens of AIP, classical chronic pancreatitis (CP), and normal pancreas (NP). Infiltrating immune cells were characterized by immunohistochemistry (IHC). Gene expression of IL-17A, IL-21, and RORC were found to be significantly increased in AIP. Accordingly, the number of Th17 cells was significantly increased in AIP compared to NP or CP. Both gene expression analysis and IHC revealed a clear difference between type 1 and 2 AIP. In the periductal compartment of type 2 AIP, which is characterized by granulocytic epithelial lesions (GELs), the number of infiltrating Th17 cells and neutrophilic granulocytes was significantly increased compared to type 1 AIP. Our data suggest that Th17 cells play a role in the pathogenesis of AIP, in particular of type 2 AIP. Cross-talk between Th17 cells and neutrophilic granulocytes mediated via IL-17A may be a potential mechanism by which neutrophils are recruited to the duct and acinar cells with subsequent destruction, a process that is pathognomonic for type 2 AIP.

Dissecting susceptibility from exogenous triggers: the model of alopecia areata and associated inflammatory skin diseases.

BACKGROUND: Alopecia areata (AA) is a T-cell-driven autoimmune disease of the hair follicle and frequently reported to be associated with inflammatory skin diseases (ISD) such as atopic eczema (AE) or psoriasis. Interestingly, AA on the one hand and both AE and psoriasis on the other hand are believed to be driven by mutually antagonistic T-cell subsets. OBJECTIVE: To characterize AA-specific T-cell profiles and inflammatory pattern by intra-individual comparison of AA and coexistent ISD. METHODS: 112 patients with AA were recruited and investigated for coexisting ISD. In-depth analyses were performed in patients with AA and AE (n = 2), AA and psoriasis (n = 1), AA and psoriasis and AE (n = 1) and AA and lichen planus (n = 1), using histology, immunohistochemistry and cytokine staining of T cells isolated from lesional skin. RESULTS: Of 112 AA patients investigated, 23 suffered from an ISD. The prevalence of AE, vitiligo, psoriasis and lichen planus was higher in the investigated AA cohort than in the normal population. The clinical as well as histological phenotype of AA the coexistent ISD were unequivocal. In line with this, T-cell infiltrates were found to be disease-characteristics with AA and lichen planus dominated by CD8+ and IFN-γ+ TNF-α+ producing T cells while psoriasis lesions in the same patients were dominated by IL-17+ and AE by IL-4+ T cells. CONCLUSION: AA patients have a higher incidence of various T-cell-driven inflammatory skin diseases than the normal population, a phenomenon which might relate to over-activation of skin-homing T cells and to specific immune triggers as the primary cause of inflammation. More importantly, we showed that by using AA as a model disease, our approach of intra-individual comparison of distinct inflammatory responses in the same patient is feasible and offers the unique possibility to gain insights into disease pathogenesis independent from genetic susceptibilities.