Non-lesional Skin Research Articles

Apocrine gland damage and the release of specific keratins in early stage indicate the crucial involvement of apocrine glands in hidradenitis suppurativa.

The apocrine glands (AGs) are not considered to be primarily involved in hidradenitis suppurativa (HS). This study investigated the potential role of AGs in HS pathogenesis using immunohistochemistry and single-cell sequencing of nonlesional skin (NLS) and early lesional skin (LS) from patients with HS (n = 12) and healthy controls (HC, n = 8). AG cell destruction was more frequent and AG size was significantly reduced in the NLS and LS. Barrier-related genes (e.g., claudin 1 and E-cadherin) were downregulated in the AGs of the NLS and LS. Damaged AGs in the LS primarily recruit and activate neutrophils via the CXCL-CXCR and SAA1-FPR2 pathways. Elevated levels of specific keratins (KRT18 and KRT19) released from damaged AGs were observed on the skin surface of patients and were associated with disease severity. KRT19 was also detected in the dermis of the NLS and LS and was surrounded by neutrophils and macrophages. Moreover, serum KRT19 levels in patients (n = 20) were significantly negatively correlated with the age at HS onset. Collectively, our findings provide previously unreported evidence that the AGs are damaged and release specific keratins in early HS lesions, indicating a crucial role of the AGs in HS pathogenesis.

Integrating multiomics sequencing analyses uncover the key mechanisms related to oxidative stress, mitochondria, and immune cells in keloid

BackgroundThis study aimed to investigate the key molecular mechanisms underlying keloid pathogenesis by integrating oxidative stress, mitochondria, and immune cells. MethodsTranscriptome sequencing (mRNA, lncRNA, and circRNA expression data), proteomic sequencing, and small RNA sequencing analyses of lesional and non-lesional skin of patients with keloids and healthy control (normal) skin were conducted. By integrating mRNA and publicly available gene expression data (GSE158395), differentially expressed genes related to oxidative stress and mitochondrial function in keloids were identified. Hub genes were identified using various bioinformatics analyses such as immune infiltration analysis, weighted gene co-expression network analysis, machine learning, and expression validation using proteomics sequencing data. Moreover, a competing endogenous RNA (ceRNA) network of hub genes was constructed by combining miRNA, lncRNA, and circRNA expression data. Five hub genes were identified: MGST1, DHCR24, ALDH3A2, ADH1B, and FKBP5. ResultsThese hub genes had a high diagnostic value for keloids, with an AUC value > 0.8 each. In addition, five hub genes were associated with the infiltration of multiple immune cells. The immune cells with the strongest positive and negative correlations with hub genes were M0 and M1 macrophages. A ceRNA network was constructed, and several ceRNAs, such as AC005062.1/miR-134-5p/FKBP5 and BASP1-AS1/miR-503-5p/ADH1B, were identified. These five hub genes may contribute to keloid pathogenesis. ConclusionThese genes and their related ceRNAs may serve as diagnostic biomarkers and therapeutic targets for keloids.

Profiling of Toll-like Receptors and Related Signaling Mediators in the Pathogenesis of Morphea

Introduction: Morphea, also known as localized scleroderma, is a rare fibrosing inflammatory disease of unknown pathogenesis. Objectives: Although the genetic basis for morphea is important, the evaluation of Toll-like receptors (TLR) in this disease is quite limited. We aimed to evaluate TLR expression levels and serum IL-6, IL-17A, TGF-b1, FGF, and VEGF levels in patients with morphea, and compare these results with healthy controls. Methods: The expression levels of TLRs in the lesional and non-lesional adjacent skin of patients with morphea, and normal skin of healthy controls were evaluated by RT-PCR whereas serum levels of IL-6, IL-17A, TGF-b1, FGF, and VEGF were evaluated by ELISA. Results: Based on our findings, TLR1 gene expression increased 34.3-fold in the lesional skin of patients with morphea. In addition, IL-6, IL-17A, TGF-β, FGF and VEGF were found to be higher in the blood samples of the patient group than in the healthy group. Conclusion: TLRs are important parts of the pathogenesis of morphea, and a better understanding of it will lead to more directed and effective treatments. We believe that this study will be important for pioneering TLR-targeted therapeutic approaches in the treatment of morphea in the future.

The Expression of Cytokines and Chemokines Potentially Distinguishes Mild and Severe Psoriatic Non-Lesional and Resolved Skin from Healthy Skin and Indicates Different Stages of Inflammation

In the psoriatic non-lesional (PS-NL) skin, the tissue environment potentially influences the development and recurrence of lesions. Therefore, we aimed to investigate mechanisms involved in regulating tissue organization in PS-NL skin. Cytokine, chemokine, protease, and protease inhibitor levels were compared between PS-NL skin of patients with mild and severe symptoms and healthy skin. By comparing mild and severe PS-NL vs. healthy skin, differentially expressed cytokines and chemokines suggested alterations in hemostasis-related processes, while protease inhibitors showed no psoriasis severity-related changes. Comparing severe and mild PS-NL skin revealed disease severity-related changes in the expression of proteases, cytokines, and chemokines primarily involving methyl-CpG binding protein 2 (MECP2) and extracellular matrix organization-related mechanisms. Cytokine and chemokine expression in clinically resolved versus healthy skin showed slight interleukin activity, differing from patterns in mild and severe PS-NL skin. Immunofluorescence analysis revealed the severity-dependent nuclear expression pattern of MECP2 and decreased expression of 5-methylcytosine and 5-hydroxymethylcytosine in the PS-NL vs. healthy skin, and in resolved vs. healthy skin. Our results suggest distinct cytokine–chemokine signaling between the resolved and PS-NL skin of untreated patients with varying severities. These results highlight an altered inflammatory response, epigenetic regulation, and tissue organization in different types of PS-NL skin with possibly distinct, severity-dependent para-inflammatory states.

Microbial imbalance in Darier disease: Dominance of various staphylococcal species and absence of Cutibacteria

Darier disease (DD) is a rare autosomal dominant genodermatosis characterized by erythematous papules and plaques mainly involving sebaceous areas, such as the face, chest and back. Skin microbiome plays an essential role in maintaining skin homeostasis. A disturbed skin microbiome may contribute to the exacerbation of DD. We investigated the bacterial composition of two predilectional sites in DD patients and healthy individuals. We also measured the microbiome composition of deeper skin layers, where diversity was significantly reduced compared to the superficial layer of the skin from the same area. The microbiome of DD patients at lesional sites differed from that of non-lesional skin areas; moreover, non-lesional sites were different from those of the controls. Lesional areas were dominated by Staphylococcus species, such as S. aureus, S. epidermidis, S. hominis, S. sciuri, and S. equorum. However, levels of Cutibacterium acnes (formerly Propionibacterium acnes) and C. acnes subspecies defendens were significantly lower in lesional sites than in non-lesional sites. A significant decrease was measured in the levels of these two bacteria between non-lesional and control samples. Our findings may indicate that alterations in the skin microbiome could contribute to the inflammation of skin lesions in DD.

Hand eczema and changes in the skin microbiome after 2 weeks of topical corticosteroid treatment.

More than 50% of patients with hand eczema (HE) are colonized with Staphylococcus aureus. Comprehensive knowledge of the skin microbiome and its changes in patients with HE may provide insights into future potential therapeutical targets. To describe the skin microbiome in patients with moderate-to-severe chronic HE and assess its changes following treatment with topical corticosteroids (TCS). Bacterial samples were collected from lesional and nonlesional skin before and after 2 weeks of TCS treatment using ESwabs and analysed by 16S rRNA and tuf gene sequencing. Clinically, the disease severity was assessed by the Hand Eczema Severity Index (HECSI). A cohort of 31 patients with HE were included and followed up. Compared to nonlesional skin, lesional skin differed in overall bacterial community composition (p = 0.02), displayed higher relative abundance of Staphylococcus, in particular S. aureus (p = 0.01) and lower abundance of Micrococcus (p = 0.02). As disease severity improved with treatment, these microbial characteristics on lesional skin shifted towards that of nonlesional skin on the hands. The bacterial skin microbiome was altered in lesions of HE and partly driven by S. aureus colonization, however, shifted towards nonlesional skin following treatment. Our results emphasize the future possibilities for anti-S. aureus treatment strategies.

Lesional Psoriasis is Associated With Alterations in the Stratum Corneum Ceramide Profile and Concomitant Decreases in Barrier Function.

Psoriasis is an inflammatory skin disease associated with an impaired skin barrier. The skin barrier function is dependent on the extracellular lipid matrix which surrounds the corneocytes in the stratum corneum. Ceramides comprise essential components of this matrix. Alterations in the stratum corneum ceramide profile have been directly linked to barrier dysfunction and might be an underlying factor of the barrier impairment in psoriasis. In this study, we investigated the ceramide profile and barrier function in psoriasis. Lesional and non-lesional skin of 26 patients and 10 healthy controls were analysed using in-depth ceramide lipidomics by liquid chromatography-mass spectrometry. Barrier function was assessed by measuring transepidermal water loss. Lesional skin showed a significant decrease in the abundance of total ceramides with significant alterations in the ceramide subclass composition compared to control and non-lesional skin. Additionally, the percentage of monounsaturated ceramides was significantly increased, and the average ceramide chain length significantly decreased in lesional skin. Altogether, this resulted in a markedly different profile compared to controls for lesional skin, but not for non-lesional skin. Importantly, the reduced barrier function in lesional psoriasis correlated to alterations in the ceramide profile, highlighting their interdependence. By assessing the parameters 2 weeks apart, we are able to highlight the reproducibility of these findings, which further affirms this connection. To conclude, we show that changes in the ceramide profile and barrier impairment are observed in, and limited to, lesional psoriatic skin. Their direct correlation provides a further mechanistic basis for the concomitantly observed impairment of barrier dysfunction.

Co-Expression Network and Machine Learning Analysis of Transcriptomics Data Identifies Distinct Gene Signatures and Pathways in Lesional and Non-Lesional Atopic Dermatitis.

Atopic dermatitis (AD) is a common inflammatory skin condition with complex origins. Current treatments often yield suboptimal results due to an incomplete understanding of its underlying mechanisms. This study aimed to identify pathway and gene signatures that distinguish between lesional AD, non-lesional AD, and healthy skin. We conducted differential gene expression and co-expression network analyses to identify differentially co-expressed genes (DCEGs) in lesional AD vs. healthy skin, lesional vs. non-lesional AD, and non-lesional AD vs. healthy skin. Modules associated with lesional and non-lesional AD were identified based on the correlation coefficients between module eigengenes and clinical phenotypes (|R| ≥ 0.5, p-value < 0.05). Subsequently, we employed Ingenuity Pathway Analysis (IPA) on the identified DCEGs, followed by machine learning (ML) analysis within the pathway expression framework. The ML analysis of pathway expressions, selected by IPA and derived from gene expression data, identified relevant pathway signatures, which were validated using an independent dataset and correlated with AD severity measures (EASI and SCORAD). We identified 975, 441, and 40 DCEGs in lesional vs. healthy skin, lesional vs. non-lesional, and non-lesional vs. healthy skin, respectively. IPA and ML analyses revealed 25 relevant pathway signatures, including wound healing, glucocorticoid receptor signaling, and S100 gene family signaling pathways. Validation confirmed the significance of 10 pathway signatures, which were correlated with the AD severity measures. DCEGs such as MMP12 and S100A8 demonstrated high diagnostic efficacy (AUC > 0.70) in both the discovery and validation datasets. Differential gene expression, co-expression networks and ML analyses of pathway expression have unveiled relevant pathways and gene signatures that distinguish between lesional, non-lesional, and healthy skin, providing valuable insights into AD pathogenesis.

CERS1 is a biomarker of Staphylococcus aureus abundance and atopic dermatitis severity

BackgroundAtopic dermatitis (AD) is an inflammatory skin condition characterized by widely variable cutaneous Staphylococcus aureus abundance that contributes to disease severity and rapidly responds to type 2 immune blockade (i.e., dupilumab). The molecular mechanisms regulating S. aureus levels between AD subjects remain poorly understood. ObjectiveTo investigate host genes that may be predictive of S. aureus abundance and correspond with AD severity. MethodsData derived from the NIH/NIAID-funded (NCT03389893 [ADRN-09]) randomized, double-blind, and placebo-controlled multicenter study of dupilumab in adults (n=71 subjects) with moderate-severe AD. Bulk RNA-sequencing of skin biopsies (n=57 lesional, 55 non-lesional) was compared to epidermal S. aureus abundance, lipidomics, and AD clinical measures. ResultsS. aureus abundance and ceramide synthase 1 (CERS1) expression positively correlated at baseline across both non-lesional (r=0.29, p=0.030) and lesional (r=0.41, p=0.0015) skin. Lesional CERS1 expression also positively correlated with AD severity (i.e., SCORing AD [SCORAD] r=0.44, p=0.0006) and skin barrier dysfunction (transepidermal water loss area under the curve [TEWL AUC] r=0.31, p=0.025) at baseline. CERS1 expression (forms C18:0-sphingolipids) was negatively associated with elongation of very long chain fatty acids (ELOVL6; C16:0→C18:0) expression and corresponded with a shorter chain length sphingolipid composition. Dupilumab rapidly reduced CERS1 expression (day 7) and ablated the relationship with S. aureus abundance and ELOVL6 expression by day 21. ConclusionCERS1 is a unique molecular biomarker of S. aureus abundance and AD severity that may contribute to dysfunctional skin barrier and shorter chain sphingolipid composition through fatty acid sequestration as a maladaptive compensatory response to reduced ELOVL6.

The skin microbiome stratifies patients with cutaneous T cell lymphoma and determines event-free survival

Mycosis fungoides (MF) is the most common entity of Cutaneous T cell lymphomas (CTCL) and is characterized by the presence of clonal malignant T cells in the skin. The role of the skin microbiome for MF development and progression are currently poorly understood. Using shotgun metagenomic profiling, real-time qPCR, and T cell receptor sequencing, we compared lesional and nonlesional skin of 20 MF patients with early and advanced MF. Additionally, we isolated Staphylococcus aureus and other bacteria from MF skin for functional profiling and to study the S. aureus virulence factor spa. We identified a subgroup of MF patients with substantial dysbiosis on MF lesions and concomitant outgrowth of S. aureus on plaque-staged lesions, while the other MF patients had a balanced microbiome on lesional skin. Dysbiosis and S. aureus outgrowth were accompanied by ectopic levels of cutaneous antimicrobial peptides (AMPs), including adaptation of the plaque-derived S. aureus strain. Furthermore, the plaque-derived S. aureus strain showed a reduced susceptibility towards antibiotics and an upregulation of the virulence factor spa, which may activate the NF-κB pathway. Remarkably, patients with dysbiosis on MF lesions had a restricted T cell receptor repertoire and significantly lower event-free survival. Our study highlights the potential for microbiome-modulating treatments targeting S. aureus to prevent MF progression.

Transcriptional Profiling of Staphylococcus aureus during the Transition from Asymptomatic Nasal Colonization to Skin Colonization/Infection in Patients with Atopic Dermatitis.

Staphylococcus aureus acts both as a colonizing commensal bacterium and invasive pathogen. Nasal colonization is associated with an increased risk of infection caused by the identical strain. In patients with atopic dermatitis (AD), the degree of S. aureus colonization is associated with the severity of the disease. Here, we comparatively analyzed the in vivo transcriptional profile of S. aureus colonizing the nose and non-diseased skin (non-lesional skin) as opposed to the diseased skin (lesional skin-defined here as infection) of 12 patients with AD. The transcriptional profile during the asymptomatic colonization of the nose closely resembled that of the lesional skin samples for many of the genes studied, with an elevated expression of the genes encoding adhesion-related proteins and proteases. In addition, the genes that modify and remodel the cell wall and encode proteins that facilitate immune evasion showed increased transcriptional activity. Notably, in a subgroup of patients, the global virulence regulator Agr (accessory gene regulator) and downstream target genes were inactive during nasal colonization but upregulated in the lesional and non-lesional skin samples. Taken together, our results demonstrate a colonization-like transcriptional profile on diseased skin and suggest a role for the peptide quorum sensing system Agr during the transition from asymptomatic nasal colonization to skin colonization/infection.

Epidermal proteomics demonstrates Elafin as a psoriasis-specific biomarker and highlights increased anti-inflammatory activity around psoriatic plaques.

Eczema and psoriasis are common diseases. Despite both showing active epidermal contribution to the inflammatory process, their molecular aetiology and pathological mechanisms are different. Further molecular insight into these differences is therefore needed to enable effective future diagnostic and treatment strategies. The majority of our mechanistic and clinical understanding of psoriasis and eczema is derived from RNA, immunohistology and whole skin biopsy data. In this study, non-invasive epidermal sampling of lesional, perilesional and non-lesional skin from diseased and healthy skin was used to perform an in depth proteomic analysis of epidermal proteins. Our findings confirmed the psoriasis-associated cytokine IL-36γ as an excellent protein biomarker for lesional psoriasis. However, ELISA and ROC curve analysis of 53 psoriasis and 42 eczema derived samples showed that the sensitivity and specificity were outperformed by elastase-specific protease inhibitor, elafin. Of note, elafin was also found upregulated in non-lesional psoriatic skin at non-predilection sites demonstrating inherent differences between the non-involved skin of healthy and psoriatic individuals. Mass spectrometry and ELISA analysis also demonstrated the upregulation of the anti-inflammatory molecule IL-37 in psoriatic perilesional but not lesional skin. The high expression of IL-37 surrounding psoriatic plaque may contribute to the sharp demarcation of inflammatory morphology changes observed in psoriasis. This finding was also specific for psoriasis and not seen in atopic dermatitis or autoimmune blistering perilesional skin. Our results confirm IL-36γ and add elafin as robust, hallmark molecules distinguishing psoriasis and eczema-associated inflammation even in patients under systemic treatment. Overall, these findings highlight the potential of epidermal non-invasive sampling and proteomic analysis to increase our diagnostic and pathophysiologic understanding of skin diseases. Moreover, the identification of molecular differences in healthy-looking skin between patients and healthy controls highlights potential disease susceptibility markers and proteins involved in the initial stages of disease.

Single-cell and spatial transcriptomics of vulvar lichen sclerosus reveal multi-compartmental alterations in gene expression and signaling cross-talk.

Vulvar diseases are a critical yet often neglected area of women's health, profoundly affecting patients' quality of life and frequently resulting in long-term physical and psychological challenges. Lichen sclerosus (LS) is a chronic inflammatory skin disorder that predominantly affects the vulva, leading to severe itching, pain, scarring, and an increased risk of malignancy. Despite its profound impact on affected individuals, the molecular pathogenesis of vulvar LS (VLS) is not well understood, hindering the development of FDA-approved therapies. Here, we utilize single-cell and spatial transcriptomics to analyze lesional and non-lesional skin from VLS patients, as well as healthy control vulvar skin. Our findings demonstrate histologic, cellular, and molecular heterogeneities within VLS, yet highlight unifying molecular changes across keratinocytes, fibroblasts, immune cells, and melanocytes in lesional skin. They reveal cellular stress and damage in fibroblasts and keratinocytes, enhanced T cell activation and cytotoxicity, aberrant cell-cell signaling, and increased activation of the IFN, JAK/STAT, and p53 pathways in specific cell types. Using both monolayer and organotypic culture models, we also demonstrate that knockdown of select genes, which are downregulated in VLS lesional keratinocytes, partially recapitulates VLS-like stress-associated changes. Collectively, these data provide novel insights into the pathogenesis of VLS, identifying potential biomarkers and therapeutic targets for future research.

Changes in epidermal thickness and their correlation with clinical characteristics in patients with vitiligo

Vitiligo is an autoimmune disorder characterized by epidermal melanocyte damage, with the typical clinical manifestation of white patches of skin. Keratinocytes, which work in concert with melanocytes to maintain the structural and functional integrity of the skin, are implicated in the progression of vitiligo. Recent studies have reported abnormal keratinocyte proliferation and epidermal thickening in some patients with vitiligo; however, the relationship between these changes and the clinical characteristics of vitiligo remains unclear. We assessed the changes in epidermal thickness in patients with vitiligo and their correlation with clinical characteristics. Compared to the non-lesional skins, the stratum corneum, viable epidermis, and full epidermis in the lesional skins were all significantly thicker. The thickness of the stratum corneum in the head, neck, and trunk was greatly lower than that in the extremities. The thickness of the stratum corneum in the sun-exposed area was higher than that in the sun-protected area, whereas the thickness of the viable epidermis decreased. In conclusion, our study found that the epidermis in the lesional skins of patients with vitiligo was significantly thickened, especially in the sun-exposed areas and extremities.

Assessment of 11 β-Hydroxysteroid Dehydrogenase Type I Activity in Patients With Psoriasis Vulgaris: A Novel Insight Into the Pathogenesis of the Disease.

Background Psoriasis is a relapsing dermatologic disease with a complex multifactorial etiology. Accumulating evidence has established the presence of cutaneous steroidogenesis with 11 β-hydroxysteroid dehydrogenase (11βHSD) enzyme being the most important final step of this pathway. This enzyme can control local levels of activated glucocorticoids (GCs) in the skin, which is the key to maintaining healthy skin. Methods This case-control study was conducted to evaluate 11βHSD1 level in psoriasis patients, in both lesional and non-lesional skin, compare it to controls, and correlate its activity with the Psoriasis Area and Severity Index (PASI) and the Perceived Stress Scale (PSS). Results A significant decrease of 11βHSD1 level in psoriasis patients compared to healthy controls was observed. In addition, decreased 11βHSD1 level was observed in lesional compared to non-lesional skin in psoriasis patients. There was no significant correlation between the enzyme levels and PASI score or PSS score in patients with psoriasis. However, the PSS score was negatively correlated with 11βHSD1 level in healthy controls. Further histopathological assessment revealed that lower enzyme levels were associated with greater epidermal acanthosis and inflammation. Conclusion This shows the role of 11βHSD1 in controlling psoriatic inflammation, including the degree of epidermal proliferation, which might reveal the complex symphony of psoriasis pathogenesis.

Abstract We067: A meta-analysis of RNA sequencing data to characterize immune cell activation among patients with cardiac sarcoidosis

Introduction: Cardiac sarcoidosis (CS) is a life-threatening auto-immune disorder that causes the formation of non-caseating granulomas in cardiac tissue. Th17.1 cell have been found to be upregulated in patients with pulmonary sarcoidosis (PS) although data is lacking among CS patients. This meta-analysis integrates all publicly available granuloma single-cell and single-nuclei RNA sequencing data to identify patterns in immune cell activation across different granulomatous diseases while focusing on CD4+T cell activation among CS patients. Methods: Five studies were included, spanning cardiac tissue from healthy controls and DCM (Koenig 2022, PMID:35959412), cardiac tissue from ICM and cardiac sarcoidosis (Liu 2022, PMID:36111531), BAL from beryllium sensitized, chronic berylliosis, and PS (Liao 2021, PMID: 33602861), peripheral blood samples from sarcoidosis (Garman 2020, PMID: 33363531), and lesional and nonlesional skin tissue from sarcoidosis (Krausgruber 2023, PMID: 36750099) for a total of 122 patients. All integrative analysis was performed using the R package Seuratv5 on Stanford’s computing cluster, Sherlock. After quality control filtering, a total of 127,335 cells were integrated using Seurat’s reference-based integration. After labeling the UMAP with general immune cells (figure 1A), we subsetted T cells into CD4+ and CD8+ and examined the landscape of CD4+ T cells (figure 1B). Results: We found significantly more Tregs in CS than PS (P=0.013, figure 1C). Additionally, patients with CS had significantly more Th17.1 cells in CS in comparison to PS (P=0.0041). However, significantly less Th2 cells were found in CS than PS patients (P=0.0152). These differences remained statistically significant across various analyses comparing Tregs and Th17.1 cell as a proportion of CD4+, CD3+, and CD45+ cells. Conclusions: In comparison to patients with PS, pathways which differentiate naive CD4+ cells into TH17.1 and Tregs are upregulated among CS patients while the TH2 differentiation pathway is downregulated. Our findings indicate distinct CD4+ T cell patterns among CS and PS patients. Our ongoing work aims to further evaluate T cell proliferation and expression to elucidate mechanistic pathways as potential drug targets for CS.

Skin microdialysis detects distinct immunologic patterns in chronic inflammatory skin diseases

BackgroundInsight into the pathophysiology of inflammatory skin diseases, especially at the proteomic level, is severely hampered by the lack of adequate in situ data. ObjectiveCharacterize lesional and nonlesional skin of inflammatory skin diseases using skin microdialysis. MethodsSkin microdialysis samples from patients with atopic dermatitis (AD, n=6), psoriasis vulgaris (PSO, n=7) or prurigo nodularis (PN, n=6), as well as healthy controls (n=7) were subjected to proteomics and multiplex cytokine analysis. Single-cell RNA sequencing of skin biopsy specimens was used to identify the cellular origin of cytokines. ResultsAmong the top 20 enriched GO annotations, NAD metabolic process, regulation of secretion by cell, and pyruvate metabolic process were elevated in microdialysates from lesional AD skin compared with both nonlesional skin and controls. The top 20 enriched KEGG pathways in these three groups overlapped almost completely. In contrast, nonlesional skin from patients with PSO or PN and control skin showed no overlap with lesional skin in this KEGG pathway analysis. Lesional skin from patients with PSO, but not AD or PN, showed significantly elevated protein levels of MCP-1 compared to nonlesional skin. IL-8 was elevated in lesional vs nonlesional AD and PSO skin, whereas IL-12p40 and IL-22 were higher only in lesional PSO skin. Integrated single-cell RNA-seq data revealed identical cellular sources of these cytokines in AD, PSO and PN. ConclusionBased on microdialysate, proteomic data of lesional PSO and PN skin, but not lesional AD skin, differed significantly from those of nonlesional skin. IL-8, IL-22, MCP-1 and IL-12p40 might be suitable markers for minimally invasive molecular profiling.

Characterization of the forehead skin microbiome in the early phase of acne.

The skin microbiota is known to be imbalanced in acne vulgaris, but the changes occurring during the early stages of acne onset remain poorly described. To characterize the skin microbiome of subclinical stages of acne in adults and adolescents. The composition and diversity of the microbiota from non-lesional skin on the forehead of subjects with mild-to-moderate acne were compared to the ones from non-acne subjects. Analyses of skin swab samples were performed using high-throughput sequencing of the V1-V3 regions of the bacterial 16S ribosomal RNA gene, the tuf gene fragment of Staphylococcus species and the internal transcribed spacer (ITS1) region of the fungal rRNA gene to determine the relative abundance, alpha-diversity and beta-diversity of bacteria and fungi. Compared with non-acne subjects, acne subjects had a higher abundance of Cutibacterium (72.4% vs. 57.8%) and lower abundances of Corynebacterium (2.8% vs. 4.8%) and Streptococcus (1.4% vs. 3.2%). Bacterial alpha- and beta-diversity indices also differed significantly between the two groups, reflecting differences in richness, evenness, abundance and phylogenetic distance between bacterial populations. Differences were also observed at the level of Staphylococcus species: S. capitis was predominant in skin samples from non-acne subjects (46.7%), whereas S. epidermidis was the most abundant Staphylococcus species in non-lesional forehead skin areas of acne subjects (44.2%). Conversely, no significant between-group differences were found for fungi, with Malasseziales being the predominant order in both subject groups. Dysbiosis was observed very early in subclinical acne stages of the forehead skin, with the overall abundance, richness and evenness of the bacterial population being lower in acne than in non-acne skin samples. Dysbiosis was also found at the level of Staphylococcus species. The development of acne lesions could therefore be prevented by using a skin care product that rebalances facial skin microbiota at very early stages.

Gasdermin A (GSDMA) Tissue Expression, Serum and Urinary Concentrations with Clinicopathologic Outcome in Psoriasis.

Psoriasis is a frequent and incurable skin disease that is an important issue in contemporary dermatology, although its pathogenesis is still uncertain. Gasdermin A (GSDMA) is a member of the gasdermin protein family which are able to cause pore formation in cellular membranes leading to cell death called pyroptosis. Our aim was to investigate the role of GSDMA in psoriatic patients. The study enrolled 60 patients with active plaque-type psoriasis and 30 sex- and age-matched volunteers without dermatoses. GSDMA concentration was assessed in serum and urine samples of all participants using ELISA. GSDMA tissue expression was assessed by immunohistochemistry. GSDMA serum concentration was significantly higher in patients compared to controls, whereas urinary GSDMA/creatinine ratio was insignificantly lower. GSDMA tissue expression was more prominent in psoriatic plaque compared to non-lesional patients' skin and healthy skin of subjects without dermatoses. There was a strong negative correlation between GSDMA serum concentration and ALT activity. GSDMA did not correlate with PASI or psoriasis duration. Obtained results point to the probable involvement of GSDMA in psoriasis. GSDMA overexpression may probably lead to keratinocytes hyperproliferation and be responsible for triggering inflammation in psoriatic skin. Serum GSDMA could become psoriasis biomarker, whereas urinary GSDMA, not at this point.

Assessment of NB-UVB Effects on Skin of Atopic Dermatitis Patients: A Network Analysis.

Introduction: Atopic dermatitis is a common inflammatory skin disease which is treated with narrowband ultraviolet B (NB-UVB). Exploring the critical targeted genes in patients by UV radiation is the main aim of this study. Methods: Gene expression profiles of lesional and non-lesional skin samples of atopic dermatitis patients after treatment with NB-UVB and the non-irradiated samples were extracted from the Gene Expression Omnibus (GEO) database and analyzed via protein-protein interaction (PPI) network analysis to find the critical targeted genes. Results: A total of 357 significant differentially expressed genes (DEGs) were included in the PPI network. CTNNB1, SRSF1, YWHAB, SMC3, GNB2, ARF3, UBL7, RAB2A, YWHAE, EIF5B, SNRPE, PPIG, RC3H2, CFL1, SMARCB1. LAPTM5, PRPF40A, and RBBP4 were introduced as hub-bottlenecks. Conclusion: In conclusion, five central genes including SMC3, ARF3, EIF5B, SMARCB1, and LAPTM5 were highlighted as the critical genes in response to NB-UVB radiation in the skin of the treated atopic dermatitis patients. The introduced crucial genes are involved in essential cellular functions such as apoptosis, cell cycle, cell proliferation, and inflammation. It seems that applied NB-UVB radiation is a suitable therapeutic method for atopic dermatitis disease.