VEXAS syndrome: A review of cutaneous findings and treatments in an emerging autoinflammatory disease.

VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory and somatic mutation) syndrome is a novel autoinflammatory, late-onset, disorder first identified in 2020. It is caused by mutations in the UBA1 gene. The most prominent clinical features reported by VEXAS patients are cutaneous and haematological, having characteristic skin features reported as the initial presenting findings of the disease. VEXAS is a severe and treatment-resistant condition with high morbidity and mortality rates. Here, we examine all case reports and case series of VEXAS syndrome through March 2023 focusing on those presenting cutaneous manifestations. We discuss these manifestations and their reported treatment strategies. In many cases, it might be first suspected and diagnosed by dermatologists, highlighting their vital role in initiating timely multidisciplinary care.

The Contribution of the Skin Microbiome to Psoriasis Pathogenesis and Its Implications for Therapeutic Strategies.

Psoriasis is a common chronic inflammatory skin disease, associated with significant morbidity and a considerable negative impact on the patients' quality of life. The complex pathogenesis of psoriasis is still incompletely understood. Genetic predisposition, environmental factors like smoking, alcohol consumption, psychological stress, consumption of certain drugs, and mechanical trauma, as well as specific immune dysfunctions, contribute to the onset of the disease. Mounting evidence indicate that skin dysbiosis plays a significant role in the development and exacerbation of psoriasis through loss of immune tolerance to commensal skin flora, an altered balance between Tregs and effector cells, and an excessive Th1 and Th17 polarization. While the implications of skin dysbiosis in psoriasis pathogenesis are only starting to be revealed, the progress in the characterization of the skin microbiome changes in psoriasis patients has opened a whole new avenue of research focusing on the modulation of the skin microbiome as an adjuvant treatment for psoriasis and as part of a long-term plan to prevent disease flares. The skin microbiome may also represent a valuable predictive marker of treatment response and may aid in the selection of the optimal personalized treatment. We present the current knowledge on the skin microbiome changes in psoriasis and the results of the studies that investigated the efficacy of the different skin microbiome modulation strategies in the management of psoriasis, and discuss the complex interaction between the host and skin commensal flora.

Delayed type hypersensitivity reactions to various allergens may differently model inflammatory skin diseases.

BACKGROUND: Treatment of inflammatory skin diseases, including atopic dermatitis (AD) and psoriasis, is undergoing transformative changes, highlighting the need to develop experimental models of skin inflammation in humans to predict treatment responses. METHODS: We topically or intradermally administered four common sensitizers (dust mite (DM), diphencyprone (DPCP), nickel (Ni), and purified protein derivative (PPD)) to the backs of 40 healthy patients and the skin hypersensitivity response was biopsied and evaluated using immunohistochemistry, RNA-seq, and RT-PCR. RESULTS: All agents induced strong increases in cellular infiltrates (T-cells and dendritic cells) as compared to untreated skin (p < .05), with variable T helper polarization. Overall, DPCP induced the strongest immune responses across all pathways, including innate immunity (IL-1α, IL-8), Th1 (IFNγ, CXCL10), Th2 (IL-5, CCL11), and Th17 (CAMP/LL37) products, as well as the highest regulatory tone (FOXP3, IL-34, IL-37) (FDR <0.01). Nickel induced Th17 (IL-17A), Th1 (CXCL10) and Th2 (IL-4R) immune responses to a lesser extent than DPCP (p < .05). PPD induced predominantly Th1 (IFNγ, CXCL10, STAT1) and Th17 inflammation (IL-17A) (p < .05). DM induced modulation of Th2 (IL-13, CCL17, CCL18), Th22 (IL-22), and Th17/Th22 (S100A7/9/12) pathways (p < .05). Barrier defects that characterize both AD and psoriasis were best modeled by DPCP and Ni, followed by PPD, including downregulation of terminal differentiation (FLG, FLG2, LOR, LCEs), tight junction (CLDN1/CLDN8), and lipid metabolism (FA2H, FABP7)-related markers. CONCLUSION: Our data imply that DPCP induced the strongest immune response across all pathways, and barrier defects characteristic of AD and psoriasis.

Malassezia sympodialis Mala s 1 allergen is a potential KELCH protein that cross reacts with human skin.

Malassezia are the dominant commensal yeast species of the human skin microbiota and are associated with inflammatory skin diseases, such as atopic eczema (AE). The Mala s 1 allergen of Malassezia sympodialis is a ß-propeller protein, inducing both IgE and T-cell reactivity in AE patients. We demonstrate by immuno-electron microscopy that Mala s 1 is mainly located in the M. sympodialis yeast cell wall. An anti-Mala s 1 antibody did not inhibit M. sympodialis growth suggesting Mala s 1 may not be an antifungal target. In silico analysis of the predicted Mala s 1 protein sequence identified a motif indicative of a KELCH protein, a subgroup of ß-propeller proteins. To test the hypothesis that antibodies against Mala s 1 cross-react with human skin (KELCH) proteins we examined the binding of the anti-Mala s 1 antibody to human skin explants and visualized binding in the epidermal skin layer. Putative human targets recognized by the anti-Mala s 1 antibody were identified by immunoblotting and proteomics. We propose that Mala s 1 is a KELCH-like ß-propeller protein with similarity to human skin proteins. Mala s 1 recognition may trigger cross-reactive responses that contribute to skin diseases associated with M. sympodialis.

Cytologic atypia of benign inflammatory versus neoplastic cutaneous squamous lesions.

BACKGROUND: Cytologic atypia encompasses several features of abnormal cellular morphology. We sought to quantify these features in benign and premalignant/malignant squamous cell lesions to better characterize criteria for malignancy. METHODS: We conducted a rater-blinded observational study in which histopathology slides were evaluated under light microscopy, and the presence and relative quantity of 24 distinct cytological features were recorded, along with respective diagnoses. Each slide was evaluated, and the ratings were recorded and analyzed. RESULTS: The most helpful findings, whose presence in high numbers indicates an increased likelihood that the tissue sample is premalignant/malignant, were: (1) pleomorphic parakeratosis; (2) pleomorphic nuclei in the epithelium; (3) irregular nuclei; (4) thick refractile nuclear envelope; (5) presence of nuclear hyperchromasia (dark gray); (6) peripheral nucleoli; and (7) nucleolar stems. Higher values of round or oval nuclear shape and vesicular nuclei increase the likelihood that the tissue sample is benign. CONCLUSIONS: Certain nuclear features have a higher association with premalignancy/malignancy and may guide histologic evaluation of a given lesion. These findings can be used in combination with architectural features and clinical history to add to a complete diagnostic picture.

The role of diet in the management of psoriasis: a scoping review.

Psoriasis is a chronic, systemic, immune-mediated, inflammatory skin disease associated with significant comorbidities. Globally, there are an estimated 60 million people living with psoriasis (PLwP). There is a growing body of evidence on the role of diet in psoriasis management, and demand for dietary advice is high. However, there are no specific, evidence-based dietary guidelines. This scoping review summarises the literature on use and effectiveness of diet in the management of psoriasis to improve understanding of the evidence and assist PLwP and healthcare professionals (HCPs) to discuss diet. The findings were categorised into three themes: (1) dietary intakes of PLwP, (2) the perceived role of diet in psoriasis management and (3) dietary approaches to manage psoriasis symptoms. In cross-sectional studies PLwP were reported to have higher fat and lower fibre intakes compared with controls, and lower psoriasis severity was associated with higher fibre intake. However, research is limited. PLwP perceive diet to have an impact on symptoms and make dietary modifications which are often restrictive. Systematic reviews and RCTs found certain dietary approaches improved symptoms, but only in specific populations (e.g. PLwP with obesity and PLwP with coeliac disease), and evidence for supplement use is inconclusive. The grey literature provides limited guidance to PLwP; focusing on weight loss and associated comorbidities. Larger, controlled trials are required to determine dietary approaches for psoriasis management, especially in PLwP without obesity and non-coeliac PLwP. Further understanding of diet modification, information acquisition and experiences among PLwP will enhance holistic care for psoriasis management.

T cells in the skin: Lymphoma and inflammatory skin disease.

T cells are established contributors to the pathogenesis of atopic dermatitis and psoriasis; yet, whether they are the key drivers or simply unwitting participants remains incompletely understood. Conversely, malignant T cells are the undisputed culprits of cutaneous T-cell lymphoma (CTCL), a group of diseases that share key clinical, histopathologic, and molecular features with inflammatory skin disease (ISD). Here, we compare the pathogenesis of ISD and CTCL and discuss the resulting insights. Recurrent, skin-limited disease implicates skin-resident memory T cells in both ISD and CTCL. In CTCL, malignant T cells recruit benign T cells into inflammatory skin lesions, a disease-amplifying function that has also been proposed for pathogenic T cells in ISD. Mechanistically, cytokines produced by malignant T cells in CTCL and by pathogenic T cells in ISD, respectively, are likely both necessary and sufficient to drive skin inflammation and pruritus, which in turn promotes skin barrier dysfunction and dysbiosis. Therapies for ISD target T-cell effector functions but do not address the chronicity of disease, whereas treatments for CTCL target malignant T cells but not primarily the symptoms of the disease. Integrating our understanding of ISD and CTCL can result in important insights into pathogenesis and therapy that may improve the lives of patients in both of these disease groups.

Increased Mortality Risk at Septic Condition in Inflammatory Skin Disorders and the Effect of High-Fat Diet Consumption.

In recent years, attention has increasingly focused on various infectious diseases. Although some fatalities are directly attributed to the causative virus, many result from complications and reactive inflammation. Patients with comorbidities are at a higher risk of mortality. Refractory skin conditions such as atopic dermatitis, psoriasis, and epidermolysis bullosa, known for an elevated risk of sepsis, partly owe this to compromised surface barrier function. However, the detailed mechanisms underlying this phenomenon remain elusive. Conversely, although the detrimental effects of a high-fat diet on health, including the onset of metabolic syndrome, are widely recognized, the association between diet and susceptibility to sepsis has not been extensively explored. In this study, we examined the potential causes and pathogenesis of increased sepsis susceptibility in inflammatory skin diseases using a mouse dermatitis model: keratin 14-driven caspase-1 is overexpressed (KCASP1Tg) in mice on a high-fat diet. Our findings reveal that heightened mortality in the dermatitis mouse model is caused by the inflamed immune system due to the chronic inflammatory state of the local skin, and administration of LPS causes a rapid increase in inflammatory cytokine levels in the spleen. Intake of a high-fat diet exacerbates these cytokine levels. Interestingly, we also observed a reduced expression of Toll-like receptor 4 (TLR4) in monocytes from KCASP1Tg mice, potentially predisposing these animals to heightened infection risks and associated complications. Histological analysis showed a clear decrease in T and B cells in the spleen of KCASP1Tg mice fed a high-fat diet. Thickening of the alveolar wall, inflammatory cell infiltration, and alveolar hemorrhage were more prominent in the lungs of KCASP1Tg and KCASP1Tg with fat mice. We postulate that the chronic, non-infectious inflammation induces a negative feedback loop within the inflammatory cascade, and the suppressed expression of TLR4 renders the mice more susceptible to infections. Therefore, it is imperative for individuals with chronic skin inflammation to closely monitor disease progression upon infection and seek timely and appropriate treatment. Additionally, chronic inflammation of adipose tissue, induced by high-fat food intake, combined with dermatitis inflammation, may exacerbate infections, necessitating a review of dietary habits.

Impact of psychiatric comorbidities in psoriasis, hidradenitis suppurativa and atopic dermatitis: The importance of a psychodermatological approach.

BACKGROUND: There is a strong interaction between the immunological and nervous system in the skin. Lesions that are physically disfiguring and chronically relapsing have a high impact on quality of life (QoL) and can result in the emergence of psychiatric disorders. The literature data confirm a higher prevalence of psychiatric disorders in patients with psoriasis, hidradenitis suppurativa (HS) and atopic dermatitis (AD), but such data are compromised by low-quality evidence due to methodological heterogeneity. OBJECTIVES: The primary aim was to analyse the prevalence of psychiatric comorbidities in a group of psoriasis, AD and HS patients compared with a control group. The secondary aims were to evaluate the impact of psychiatric comorbidities on the disease development, severity, flare-ups and QoL. METHODS: A total of 59 cases and 64 controls were included. RESULTS: Generalized anxiety disorder and depressive disorder with anxious distress were found to be risk factors for AD. Age, smoking and substance-related disorder showed a specific association with HS. Major depressive disorder showed a specific association with dermatology life quality index (DLQI) and all the above disease flare-ups. CONCLUSIONS: Atopic dermatitis, psoriasis and HS are associated with psychiatric disorders. A psychodermatological approach improves outcomes in terms of QoL, disease flare-ups and long-term management.

Perfusion measured by laser speckle contrast imaging as a predictor for expansion of psoriasis lesions.

BACKGROUND: Skin microvasculature changes are crucial in psoriasis development and correlate with perfusion. The noninvasive Handheld Perfusion Imager (HAPI) examines microvascular skin perfusion in large body areas using laser speckle contrast imaging (LSCI). OBJECTIVES: To (i) assess whether increased perilesional perfusion and perfusion inhomogeneity are predictors for expansion of psoriasis lesions and (ii) assess feasibility of the HAPI system in a mounted modality. METHODS: In this interventional pilot study in adults with unstable plaque psoriasis, HAPI measurements and color photographs were performed for lesions present on one body region at week 0, 2, 4, 6 and 8. The presence of increased perilesional perfusion and perfusion inhomogeneity was determined. Clinical outcome was categorized as increased, stable or decreased lesion surface between visits. Patient feedback was collected on a 10-point scale. RESULTS: In total, 110 lesions with a median follow-up of 6 (IQR 6.0) weeks were assessed in 6 patients with unstable plaque psoriasis. Perfusion data was matched to 281 clinical outcomes after two weeks. A mixed multinomial logistic regression model revealed a predictive value of perilesional increased perfusion (OR 9.90; p < 0.001) and perfusion inhomogeneity (OR 2.39; p = 0.027) on lesion expansion after two weeks compared to lesion stability. HAPI measurements were considered fast, patient-friendly and important by patients. CONCLUSION: Visualization of increased perilesional perfusion and perfusion inhomogeneity by noninvasive whole field LSCI holds potential for prediction of psoriatic lesion expansion. Furthermore, the HAPI is a feasible and patient-friendly tool.

Transforming the treatment of psoriasis to the 21st century: Detecting subclinical therapeutic response to secukinumab using optical coherence tomography as a prognostic indicator.

BACKGROUND: Optical coherence tomography (OCT) is a noninvasive imaging device that scans the skin up to 2 mm in depth. OCT can capture real-time epidermal thickness (ET) measurements and detect subclinical changes in inflammatory skin diseases like eczema and psoriasis. © 2022 Wiley Periodicals LLC. OBJECTIVE: To determine if measuring ET with OCT can detect a subclinical therapeutic response in psoriasis treated with the biological therapy, secukinumab (an IL-17A antagonist). DESIGN: Phase IV, single-center, open-label, and single-arm study. PARTICIPANTS: Twenty-six consecutive patients with moderate to severe plaque psoriasis. MEASUREMENTS: Clinical, dermoscopic, and OCT images were obtained at each visit. The clinician measured disease severity with the Investigator's Global Assessment (IGA) and Psoriasis Area And Severity Index (PASI). OCT was used to scan the ET at the center of lesional skin (ET-L), along the border, and normal skin (ET-N) on the same body plane; their difference was noted as ΔET. RESULTS: Initially, ET-L was greater than ET-N (p < 0.0001), their differences decreased throughout the study, and there were no significant differences at Week 16 (p = 0.48). Twenty-four (92%) patients achieved a 50% reduction in PASI score (PASI50); they had lower ΔET at Weeks 0, 1, 3, 4, and 8 compared to those who did not clear (p < 0.04). Having a lower ΔET at Week 4 was associated with a shorter time to reach PASI50 (p = 0.02). CONCLUSION: ET measurements using OCT can detect an early subclinical response to secukinumab compared to clinical scoring and identify nonresponders as early as 4 weeks.

Human Polyomavirus 6 Detected in Cases of Eosinophilic Pustular Folliculitis.

BACKGROUND: Human polyomaviruses (HPyVs) have been associated with several cutaneous inflammatory conditions. More investigation is needed to identify further presentations of cutaneous pathology associated with HPyVs. Our aim was to investigate the possible association of skin-tropic HPyVs with folliculitis, particularly eosinophilic pustular folliculitis (EPF). METHODS: This study included 55 Japanese patients, comprising 13 patients with EPF and 42 patients with suppurative folliculitis. HPyV DNAs were detected by quantitative polymerase chain reaction. Expression of viral antigen and geographically related viral genotypes were also assessed. RESULTS: Human polyomavirus 6 (HPyV6) DNA was found in 9 of 13 (69%) patients with EPF, a rate significantly higher than that found in suppurative folliculitis (1/42; 2%). Of the 7 HPyV6 DNA-positive EPF specimens analyzed, 4 were positive for HPyV6 small tumor antigen. All the HPyV6 strains detected in this study were of the Asian/Japanese genotype. CONCLUSIONS: The predominant detection of HPyV6 DNA and the expression of viral antigen suggest a possible association between HPyV6 infection and EPF in a subset of patients. Worldwide studies are warranted to determine whether Asian/Japanese genotype HPyV6 is associated preferentially with the incidence and pathogenesis of this eosinophil-related skin disease that has an ethnic predilection for the East Asian population.

So close, and yet so far away: The dichotomy of the specific immune response and inflammation in psoriasis and atopic dermatitis.

Characterization of the complex interplay between cytokines, chemokines and microorganisms has led to a better understanding of the pathogenesis of both psoriasis and AD and resulted in new therapeutics targeting distinct immune responses. Psoriasis and AD share many characteristics: they are highly prevalent, chronic, cause primarily skin inflammation, but are associated with comorbidities, and come with a devastating quality of life due to itch and stigmatization. However, the pathogenesis of psoriasis and AD is opposing - psoriasis is dominated by a Th17 immune response that causes neutrophil migration, induction of innate immunity and exaggerated epithelial metabolism. Leading cytokines of this Th17 immune response are IL-17A and F, IL-22 and TNF-a. AD is characterized by Th2 immunity characterized by the signature cytokines IL-4 and IL-13 leading to an impaired epidermal barrier, dampened innate immunity and eosinophil migration. This review compares genetics, microbiome and T-cell infiltrate and resulting epithelial response in psoriasis and AD. Whilst the antagonistic course of psoriasis and AD is confirmed by response to specific biologics targeting the key cytokines of inflammation in psoriasis and AD, respectively, clinically overlapping phenotypes are challenging in our daily clinical practice. We conclude this review by summarizing what is known about these mixed phenotypes and how the identification of clinically relevant endotypes and molecular-driven decision-making is the next step in the field of dermato-immunology.

Association of herpes zoster and chronic inflammatory skin disease in US inpatients.

BACKGROUND: Patients with chronic inflammatory skin disease (CISD) have potential risk factors for herpes zoster (HZ). However, little is known about HZ risk in CISD. OBJECTIVE: To determine whether CISD is associated with HZ. METHODS: Data were analyzed from the 2002 to 2012 Nationwide Inpatient Sample, a representative cohort of US hospitalizations (N = 68,088,221 children and adults). RESULTS: In multivariable logistic regression models including age, sex, race/ethnicity, insurance, household income, and long-term systemic corticosteroid use, hospitalization for HZ was associated with atopic dermatitis (adjusted odds ratio [95% confidence interval], 1.38 [1.14-1.68]), psoriasis (4.78 [2.83-8.08]), pemphigus (1.77 [1.01-3.12]), bullous pemphigoid (1.77 [1.01-3.12]), mycosis fungoides (3.79 [2.55-5.65]), dermatomyositis (7.31 [5.27-10.12]), systemic sclerosis (1.92 [1.47-2.53]), cutaneous lupus erythematosus (1.94 [1.10-3.44]), vitiligo (2.00 [1.04-3.85]), and sarcoidosis (1.52 [1.22-1.90]). Only lichen planus (crude odds ratio [95% confidence interval], 3.01 [1.36-6.67]), Sézary syndrome (12.14 [5.20-28.31]), morphea (2.74 [1.36-5.51]), and pyoderma gangrenosum (2.44 [1.16-5.13]) showed increased odds in bivariable models. Sensitivity analyses among those younger than 60 and younger than 50 years showed similar results. Predictors of HZ in CISD included female sex, fewer chronic conditions, and long-term systemic corticosteroid use. LIMITATIONS: Cross-sectional study. CONCLUSIONS: Many CISDs are associated with increased hospitalization for HZ, even below the ages recommended for HZ vaccination. Additional studies are needed to establish CISD-specific vaccination guidelines.

Dapsone in hidradenitis suppurativa: A case series of 56 patients.

Hidradenitis suppurativa (HS) is a chronic inflammatory disease with a challenging treatment. Current guidelines reserve dapsone as a third line agent for patients with mild to moderate HS. To our knowledge, only four small case series have been reported. The objective of this study was to assess the effectiveness and safety of dapsone in our clinical practice. A retrospective observational single-center study of 56 HS patients who underwent treatment with dapsone from May 1, 2015, to June 1, 2021, was performed. The Hidradenitis Suppurativa Clinical Response (HiSCR) scale was used to evaluate the response to treatment. Fifty-six patients were included, 66% of which were men, with a median age of 33 years. Most of them had mild or moderate disease and belonged to LC2 follicular phenotype. All patients had been refractory to first-line treatments. Dapsone was prescribed at doses of 50-150 mg/day. 62.5% of the patients achieved HiSCR after 12 weeks of treatment. No serious adverse reactions were detected. The median duration of treatment was 8 months. After multivariate analysis, an association was found between the presence of fistulous tracts and the risk of non-response to the drug. In four of the dapsone responders, oral retinoids were added to achieve a sustained response. Limitations include the retrospective and non-controlled nature of this study. In conclusion, dapsone is an effective and well-tolerated option for long-term HS treatment, and in this series, it was mainly chosen for patients with LC2 phenotype. It would be interesting to study combination with retinoids and other management options.

Relationship Between Tea Drinking Behaviour and Rosacea: A Clinical Case-control Study.

The exact mechanisms of rosacea development are unknown, but it has been suggested that tea consumption may be associated with its development. To determine the relationship between tea drinking behaviour and rosacea, this clinical case-control study recruited 2,063 participants, who completed a questionnaire about tea drinking behaviour. A 1:1 ratio propensity score matching method was used to generate 619 cases and 619 controls. High-frequency tea drinking (3 times/day: adjusted odds ratio (aOR) 2.592; 95% confidence interval (95% CI) 1.225-5.485; ≥ 4 times/day; aOR 8.86; 95% CI 3.43-22.887), non-fermented tea (aOR 2.172; 95% CI 1.562-3.022), and hot tea (aOR 2.793; 95% CI 1.796-1.344) were associated with an increased risk of rosacea. Further results showed that these tea drinking behaviours were significantly associated with an increased risk of flushing (aOR 1.41; 95% CI 1.07-1.87) and erythema (aOR 1.48; 95% CI 1.10-2.00). Tea drinking behaviour is closely related to rosacea and.

Reflectance Confocal Microscopy, Optical Coherence Tomography, and Multiphoton Microscopy in Inflammatory Skin Disease Diagnosis.

BACKGROUND AND OBJECTIVES: Technological advances in medicine have brought about many novel skin imaging devices. This review aims to evaluate the scientific evidence supporting the use of noninvasive optical imaging techniques to aid in the diagnosis and prognosis of inflammatory skin diseases. STUDY DESIGN/MATERIALS AND METHODS: PubMed and Scopus were searched in September 2020 according to PRISMA guidelines for articles using reflectance confocal microscopy (RCM), optical coherence tomography (OCT), and multiphoton microscopy (MPM) in inflammatory skin diseases, excluding studies monitoring treatment efficacy. RESULTS: At the time of the study, there were 66 articles that addressed the utilization of noninvasive imaging in interface, spongiotic, psoriasiform, vesiculobullous, and fibrosing/sclerosing inflammatory skin dermatoses: RCM was utilized in 46, OCT in 16, and MPM in 5 articles. RCM was most investigated in psoriasiform dermatoses, whereas OCT and MPM were both most investigated in spongiotic dermatoses, including atopic dermatitis and allergic contact dermatitis. CONCLUSIONS: There is preliminary evidence to support the diagnostic potential of noninvasive optical imaging techniques in inflammatory skin diseases. Improvements in the devices and further correlation with histology will help broaden their utility. Additional studies are needed to determine the parameters for diagnostic features, disease differentiation, and staging of inflammatory skin conditions. Lasers Surg. Med. © 2021 Wiley Periodicals LLC.

Epigenetic factors involved in the pathophysiology of inflammatory skin diseases.

Epigenetics has been discussed as a potential factor influencing the pathophysiology and severity of inflammatory skin diseases. In recent years, emerging evidence suggests that epigenetic mechanisms are involved in the pathophysiology of not only atopic dermatitis (AD) and psoriasis (PSO) but also lupus erythematosus and oral lichen. A systematic review of the literature was undertaken to provide an unbiased and comprehensive update on the involvement of methylation patterns in inflammatory skin disease. In addition to reviewing the contribution of epigenetic mechanisms regulating the development of inflammatory skin diseases, this review aimed to discern the overlap of epigenetic risk factors of the 2 most common inflammatory skin diseases, AD and PSO. Although AD and PSO are both inflammatory skin diseases, both show a distinct genetic profile. Herein, we give evidence that both AD and PSO share epigenetic risk factors that might contribute to disease characteristics. We identify a core subset of inflammation-associated differentially methylated genes in both AD and PSO and discuss the association in other inflammatory diseases.

Immunomodulatory Properties of Umbilical Cord Blood-Derived Small Extracellular Vesicles and Their Therapeutic Potential for Inflammatory Skin Disorders.

Umbilical cord blood (UCB) has long been seen as a rich source of naïve cells with strong regenerative potential, likely mediated by paracrine signals. More recently, small extracellular vesicles (sEV), such as exosomes, have been shown to play essential roles in cell-to-cell communication, via the transport of numerous molecules, including small RNAs. Often explored for their potential as biomarkers, sEV are now known to have regenerative and immunomodulating characteristics, particularly if isolated from stem cell-rich tissues. In this study, we aim to characterize the immunomodulating properties of umbilical cord blood mononuclear cell-derived sEV (UCB-MNC-sEV) and explore their therapeutic potential for inflammatory skin diseases. UCB-MNC-sEV were shown to shift macrophages toward an anti-inflammatory phenotype, which in turn exert paracrine effects on fibroblasts, despite previous inflammatory stimuli. Additionally, the incubation of PBMC with UCB-MNC-sEV resulted in a reduction of total CD4+ and CD8+ T-cell proliferation and cytokine release, while specifically supporting the development of regulatory T-cells (Treg), by influencing FOXP3 expression. In a 3D model of psoriatic skin, UCB-MNC-sEV reduced the expression of inflammatory and psoriatic markers IL6, IL8, CXCL10, COX2, S100A7, and DEFB4. In vivo, UCB-MNC-sEV significantly prevented or reversed acanthosis in imiquimod-induced psoriasis, and tendentially increased the number of Treg in skin, without having an overall impact on disease burden. This work provides evidence for the anti-inflammatory and tolerogenic effect of UCB-MNC-sEV, which may be harnessed for the treatment of Th17-driven inflammatory skin diseases, such as psoriasis.

Ophiopogonin D ameliorates DNCB-induced atopic dermatitis-like lesions in BALB/c mice and TNF-α- inflamed HaCaT cell.

Atopic dermatitis (AD) can occur in both children and adults, and the symptoms include itching and eczema, which in turn cause patients to suffer. Ophiopogonin D (OP-D) is a steroidal glycoside from Radix Ophiopogon japonicus, which is well known as an effective anti-inflammatory herbal medicine in many Asian countries. In this study, we aimed to investigate the anti-inflammatory effects of OP-D, using an AD mouse model and inflamed HaCaT cells. Through a histopathological analysis, we were able to confirm the suppressive effects of OP-D on skin thickening and the mast cell activation in AD-like mouse back skin tissues stimulated by DNCB. In addition, we detected significant decreases in cytokine expression levels through multiplex assessment assays of the OP-D-treated mice blood. We observed the anti-inflammatory effect of OP-D in the spleen, causing weight loss in the spleen and in the mRNA expression levels related to diverse cytokines. In human keratinocytes inflamed by TNF-α, OP-D inhibited p38 and ERK protein activation and showed a reduction of NF-κB nuclear translocation. Furthermore, OP-D attenuated pro-inflammatory cytokine mRNA expressions in TNF-α-inflamed HaCaT cells. Accordingly, we came to the conclusion that OP-D is a potential natural drug which can be used in order to treat inflammatory skin diseases, such as AD.