The gut microbiome undergoes dynamic age-related changes shaped by diet and maternal factors. Here, we present a species-level, long-read 16S rRNA survey of the developing gut microbiome in a translational canine model, profiling 89 purebred Hungarian Pumis across early-life and reproductive stages. We collected 456 fecal samples longitudinally: 60 puppies followed from birth to 81 weeks, their mothers sampled during pregnancy and lactation, and adult controls from six kennels. We recorded detailed dietary metadata and reproductive status throughout the study. Age was the strongest determinant of alpha diversity, with a rapid increase during weaning and stabilization by 6 months of age. Beta diversity analyses revealed structured compositional transitions from early developmental phases to adulthood, including a shift toward more uniform, adult-like communities. Within-kennel variation was modest, consistent with shared environmental exposures. Mixed-effects models showed robust associations between specific taxa and age, diet, and kennel, while SparCC-inferred co-occurrence networks indicated increasing ecological complexity with age. We also demonstrated that the delivery mode-vaginal versus cesarean-impacted early-life microbiome composition: Lactobacillus spp. were significantly more abundant in cesarean-born puppies than in vaginally delivered littermates during the 8-10-week window. We also observed reproducible maternal microbiome shifts during pregnancy and lactation, with potential implications for vertical microbial transfer. Taken together, our results show that domestic dogs follow a reproducible, age-structured trajectory of microbial maturation that parallels human development, including delivery-mode effects and diet-responsive taxa.IMPORTANCEMicrobiome research is among the fastest-moving areas in biomedicine driven by major global efforts to understand how microbial communities shape human health and disease. Dogs provide an ideal translational model because their gut microbiota more closely resembles that of humans than that of other studied animals; moreover, breeds show high within-breed genetic homogeneity; diets can be tightly regulated; and longitudinal sampling across the lifespan is feasible. Mapping shifts driven by diet and maternal factors-from early-life events through later life, including senior stages-is essential to leverage microbial plasticity for prevention, with implications for inflammation, metabolic disease, and neurodegeneration. Here, we advance this goal by providing a longitudinal, high-resolution data set and demonstrating that full-length 16S rRNA sequencing is a powerful tool for resolving fine-scale patterns of gut colonization and maturation.

BACKGROUND:Atopic dermatitis (AD) and psoriasis (PSO) are chronic inflammatory skin diseases that impose substantial physical and psychological burdens. Although fungal-bacterial balance is important for skin immune homeostasis, the role of the skin mycobiome and its interaction with bacterial communities and host immunity in these diseases remains poorly understood. OBJECTIVES:To characterize alterations in the skin mycobiome and its interactions with bacterial communities and host immune responses in AD and PSO. METHODS:Adult patients with chronic AD, plaque-type PSO and healthy volunteers were included in this study. Skin microbiota samples and biopsies were collected from lesional and non-lesional skin areas, including the posterior thigh for AD and the lower back for PSO. Whole-metagenome shotgun sequencing was used to profile microbial communities. SparCC was used to construct fungal-bacterial co-occurrence networks, and integration of host transcriptomic and microbial features was performed using O2PLS. RESULTS:Both AD and PSO showed disease-associated restructuring of Malassezia species and reduced fungal-bacterial ecological connectivity in lesional skin. In AD, Malassezia arunalokei was inversely associated with Staphylococcus aureus and linked to antimicrobial peptide-centred host gene modules enriched for IL-17 signalling. Its abundance decreased with increasing disease severity and inversely correlated with inflammatory immune cell signatures. In PSO, altered Malassezia composition was associated with IL-17-driven transcriptional programmes and lipid metabolic pathways, suggesting interactions between fungal imbalance and inflammatory-metabolic processes. CONCLUSIONS:Our findings expand current models of skin dysbiosis beyond bacteria and suggest that disrupted fungal-bacterial interactions are linked to immune activation in AD and PSO and, in AD, to disease severity. Although further validation is required, skin microbiome features may provide clinically relevant information for disease monitoring, patient stratification and future microbiome-informed therapeutic strategies. Our study lays the groundwork for microbiome modulation as a potential therapeutic strategy for AD and PSO.

BACKGROUND:Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by immune dysregulation and epithelial barrier dysfunction. Although transcriptional changes in AD skin are increasingly well characterized, DNA methylation patterns remain less well understood. METHODS:Here, we present an integrated analysis of matched DNA methylomes, transcriptomes, and microbiomes from lesional (n = 40), adjacent non-lesional (n = 38), and healthy control (n = 40) skin, using complementary cell-type-adjusted models. RESULTS:We identified thousands of differentially methylated regions (DMRs) across all pairwise contrasts (lesional vs. healthy: n = 13,514; lesional vs. non-lesional: n = 4591; non-lesional vs. healthy: n = 1716), including both hyper- and hypo-methylated regions with balanced effect sizes. A core subset of DMRs persisted after methylation-based adjustment, whereas the extensive lesional vs. non-lesional set was largely composition-driven. Integration with transcriptomic co-expression networks linked DMRs to immune-epithelial modules, and 225 DMR-gene pairs showed significant anti-correlation (FDR < 0.05). Lesional skin with dominant Staphylococcus aureus colonization differed at 92 DMRs compared with absent-colonized skin, of which 70 also overlapped with local severity. Pathway analyses consistently highlighted Rho GTPase and actin-junctional programs across analytic layers, suggesting that Rho GTPase signaling is a central integrator of immune, epithelial, and microbial interactions in AD. CONCLUSIONS:Our study underscores the importance of epigenomic remodeling in AD and highlights potential avenues for precision intervention in chronic inflammatory skin disease.

In our research, we performed temporal transcriptomic profiling of host cells infected with Equid alphaherpesvirus 1 (EHV-1) by utilizing direct cDNA sequencing based on nanopore MinION technology. The sequencing reads were harnessed for transcript quantification at various time points. Viral infection-induced differential gene expression was identified through the edgeR package. The identified genes were segmented into six groups based on their kinetic characteristics. The initial three clusters encompass immediate-early response genes, typically transcription factors and elements of antiviral signaling pathways. These genes were either upregulated (cluster 1) or downregulated (clusters 2 and 3) during the early infection phase. The remaining three clusters include late response genes. In these categories, it is challenging to determine whether changes in gene expression are directly connected to the viral infection or merely side effects of the infection. A study of gene associations using the STRINGDB software revealed several gene networks that might be directly impacted by the virus. We also explored whether gene co-expression could be a result of their collective regulation by upstream transcription factors using the Gene Regulatory Network database. Finally, our differential transcript usage (DTU) analysis identified a number of genes that exhibited altered proportions of transcript isoforms in comparison to non-infected cells. Thus, our analysis revealed that EHV-1 infection not only alters host gene expression but also leads to differential use of transcript isoforms, particularly splice variants.

BACKGROUND AND PURPOSE:Psoriasis is a chronic, relapsing, immune-mediated inflammatory skin disease. The transient receptor potential ankyrin 1 (TRPA1) ion channel plays a protective role in the formation of psoriasiform skin reactions. Here, we investigated the pharmacological activation and blockade of TRPA1 in human skin (patho)physiology. EXPERIMENTAL APPROACH:Six-millimetre full-thickness biopsies were obtained from psoriatic lesional and non-lesional skin of four patients with psoriasis, and from normal skin of four healthy volunteers. Each biopsy was quartered: One segment was untreated, and the other three were cultured with vehicle (DMSO), TRPA1 agonist mustard oil (MO), or TRPA1 antagonist (HC030031), respectively. Global gene expression was measured by RNA sequencing, followed by differential expression and functional enrichment analyses, to identify TRPA1-modulated genes. KEY RESULTS:Pre-evaluation of data with ordination assessment showed clear cluster formation according to treatments and condition of the skin. In healthy skin, TRPA1 activation down-regulated genes associated with interferon signalling, antimicrobial responses, and inflammation/oxidative stress. In lesional psoriatic skin, the genes of interleukin-4 (IL-4), IL-10 and IL-13 cytokine signalling-related proteins, circadian gene expression, and senescence-associated secretory phenotype (SASP) genes were down-regulated by MO treatment. Antagonist treatment did not cause significant gene expression changes, supporting the previous finding that basal TRPA1 activity is low in the skin. DMSO treatment in all three conditions increased expression of several inflammatory genes, which was normalised during data analysis. CONCLUSION AND IMPLICATIONS:Exploration of the interactions between TRPA1 and identified signalling pathways may open new opportunities to target psoriasis, alleviate disease symptoms and optimise therapies.

ABSTRACT Background Chronic spontaneous urticaria (CSU) is a debilitating inflammatory skin disease with a prevalence of approximately 1% of the population. It is characterized by recurrent itchy wheals and/or angioedema for more than 6 weeks without known triggers leading to a high quality of life impairment. The pathogenesis of CSU remains not fully understood. Objective This study aimed to explore the pathomechanism of CSU beyond mast cells and IgE‐dependent histamine release and to identify possible biomarkers for the disease and its treatment. Methods We investigated a patient cohort in the first month of omalizumab treatment regarding the IgE levels and changes in gene and miRNA expression in peripheral blood. The cohort was divided into responders and nonresponders (depending on the score of the urticaria control test) and compared to a group of healthy controls. Results Our messenger RNA and microRNA microarray analyses revealed the greatest changes in expression levels on Day 2 after the first omalizumab dose. Conclusion We identified several genes and miRNAs of interest, most of which have not been described to be linked to CSU so far, underlining, for example, to T cell involvement or even suggesting platelet involvement.

BACKGROUND:The introduction of immune checkpoint inhibitors (ICIs) opened a new era in cancer immunotherapy. In particular, PD-1 inhibitors have shown remarkable efficacy in various cancers, most notably melanoma. However, the widespread use of immune checkpoint inhibitors comes with the challenge of immune-related adverse events (irAEs), with cutaneous toxicities being the most prevalent. METHODS:A retrospective, single-center study was carried out to investigate the cutaneous side effects in patients diagnosed with melanoma and treated with PD-1 inhibitors (pembrolizumab or nivolumab) at the Department of Dermatology, Venereology, and Oncodermatology, University of Pécs, Hungary. The study included patients with stage III or IV melanoma who received PD-1 inhibitor monotherapy, either for metastatic or adjuvant purposes, from August 2015 to May 2022. RESULTS:A cohort of 174 patients was examined, with 29% experiencing cutaneous adverse events (cAEs). The most prevalent cutaneous toxicities were vitiligo (n = 18; 27%), maculopapular rash (n = 14; 21%), pruritus (n = 14; 21%), xerostomia (n = 8; 12%), and lichenoid dermatitis (n = 4; 6%). Treatment primarily involved topical corticosteroids and emollients, with a few cases requiring systemic therapy. Notably, the occurrence of dermatologic adverse events was associated with improved progression-free survival (PFS) (p = 0.007) and overall survival (OS) (p = 0.026) compared to those without any skin toxicity (p < 0.0001), emphasizing their potential prognostic significance. Our data were not influenced by any well-known prognostic factors of melanoma. CONCLUSION:Our study contributes to the growing body of evidence supporting the prognostic value of cutaneous adverse events in patients treated with PD-1 inhibitors. Optimizing treatment strategies while maintaining oncologic therapy is essential, highlighting the role of dermatologists in multidisciplinary cancer care.

Chronic pruritus is a debilitating symptom of several inflammatory skin conditions, presenting severe quality-of-life decreasing effects and major clinical challenges in terms of disease management. In the past decade, novel biological therapies have offered increasingly effective targeted interventions for the treatment of chronic pruritus, in which traditional approaches were often lacking or presented suboptimal safety profiles. However, recent advancements in the molecular characterization of sensory neuronal subsets helped to shed light on specific mechanisms of pruriception and thus have furthered our understanding of the peripheral nervous system and disease-relevant neuroimmune crosstalk. These developments have highlighted the targeting of interleukin-31, a major pruritus-associated cytokine, as a highly promising therapeutic target for chronic pruritus in inflammatory skin conditions. In this review, we therefore provide a focused overview of inflammatory conditions in which pruritus represents the major burden, the fundamental immune pathways, and sensory circuits involved, alongside the efficacies and safety profiles of novel therapies addressing chronic pruritus.

Rosacea is characterized by inflammatory lesions, often accompanied by an increased density of the common skin mite Demodex folliculorum. Although rosacea shows a high prevalence and significantly affects the QOL of patients, the underlying mechanisms, especially the role of cutaneous dysbiosis, are largely unknown. Hence, we aimed to systematically characterize disease severity of patients with rosacea in the context of mite density, the cutaneous microbiome, and the host's transcriptome before and after 30 days of topical 1% ivermectin cream treatment. At day 30, a marked decrease in mite density was observed in 87.5% of patients. At day 0, distinct microbial community changes included the decrease in Cutibacterium acnes abundance, whereas Staphylococcus epidermidis colonization increased compared with that in healthy volunteers. Interestingly, the insect symbiont Snodgrassella alvi was recovered from a highly Demodex-colonized patient and eradicated by treatment on day 30. Although topical ivermectin did not affect bacterial dysbiosis, the host's transcriptome significantly normalized, and an "ivermectin transcriptomic signature" was defined. Findings of this study support that rosacea lesions are associated with dysbiosis. However, improvement of clinical signs during topical ivermectin is not associated with normalization of the bacterial microbiome but rather a decrease of transcriptomic dysregulation and mite density.

transcriptomics dysregulations underlying However, majority of transcriptomics studies focus on single diseases with limited relevance for understanding the molecular relationship between diseases or for identifying disease -specific markers. In this study, we used a normalization approach to compare gene expression across nine inflammatory skin diseases. The normalized datasets were found to retain differential expression signals that allowed unsupervised disease clustering and identification of disease -specific gene signatures. Using the NS -Forest algorithm, we identified a minimal set of biomarkers and validated their use as diagnostic disease classifier. Among them, PTEN was identified as being a specific marker for cutaneous lupus erythematosus and found to be strongly expressed by lesional keratinocytes in association with pathogenic type I IFNs. In fact, PTEN facilitated the expression of IFN-b and IFN-k in keratinocytes by promoting activation and nuclear translocation of IRF3. Thus, cross -comparison of tissue transcriptomics is a valid strategy to establish a molecular disease classification and to identify pathogenic disease biomarkers.

BACKGROUND:Psoriasis (Pso) is a chronic inflammatory skin disease that poses both physical and psychological challenges. Dysbiosis of the skin microbiome has been implicated in Pso, yet a comprehensive multi-omics analysis of host-microbe interactions is still lacking. To bridge this gap, we conducted an exploratory study by adopting the integrated approach that combines whole metagenomic shotgun sequencing with skin transcriptomics. METHODS:This was a cross-sectional study, adult patients with plaque-type Psoriasis (Pso) and healthy volunteers were included. Skin microbiota samples and biopsies were collected from both lesional and non-lesional skin areas on the lower back. Weighted Gene Correlation Network Analysis (WGCNA) was employed for co-expression network analysis, and cell deconvolution was conducted to estimate cell fractions. Taxonomic and functional features of the microbiome were identified using whole metagenomic shotgun sequencing. Association between host genes and microbes was analyzed using Spearman correlation. FINDINGS:Host anti-viral responses and interferon-related networks were identified and correlated with the severity of psoriasis. The skin microbiome showed a greater prevalence of Corynebacterium simulans in the PASI severe-moderate groups, which correlated with interferon-induced host genes. Two distinct psoriatic clusters with varying disease severities were identified. Variations in the expression of cell apoptosis-associated antimicrobial peptides (AMPs) and microbial aerobic respiration I pathway may partly account for these differences in disease severity. INTERPRETATION:Our multi-omics analysis revealed for the first time anti-viral responses and the presence of C. simulans associated with psoriasis severity. It also identified two psoriatic subtypes with distinct AMP and metabolic pathway expression. Our study provides new insights into understanding the host-microbe interaction in psoriasis and lays the groundwork for developing subtype-specific strategies for managing this chronic skin disease. FUNDING:The research has received funding from the FP7 (MAARS-Grant 261366) and the Innovative Medicines Initiative 2 Joint Undertaking (JU) under grant agreement No 821511 (BIOMAP). The JU receives support from the European Union's Horizon 2020 research and innovation programme and EFPIA. This publication reflects only the author's view and the JU is not responsible for any use that may be made of the information it contains. GAM was supported by a scholarship provided by CAPES-PRINT, financed by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES (Brazilian Government Agency). The authors thank all patients who participated in our study.

This research utilizes whole metagenomic shotgun sequencing to analyse the skin microbiome in patients with psoriasis, comparing lesional and nonlesional skin with those of healthy individuals. The study identifies significant differences in the microbial composition and functionality between psoriatic and healthy skin, revealing distinct microbial patterns and disruptions in psoriatic skin. These findings highlight the complex role of skin microbiota in psoriasis, emphasizing variations in bacteria and their functional characteristics beyond mere species identification.

Background and Objectives: Defined by chronic pain, rheumatic diseases are often co-occurring with anxiety and depression. Among the available psychological interventions, cognitive-behavioral therapies have an already-proven efficiency in these cases. However, the need to adjust their structure became ubiquitous during the post-pandemic period. Hence, the objective of this study was to investigate the impact of a single-session, process-based cognitive-behavioral intervention for patients with rheumatic conditions within an in-patient setting. Materials and Methods: A total of 31 participants (mean age 58.9 years) completed the single-session intervention. Assessments were conducted prior to the intervention, post-intervention and after one month. Results: Pearson’s correlations, paired samples T tests and a covariance analysis based on the Linear Mixed Model were performed for exploring the relations between baseline variables and evaluating the impact of the SSI intervention. Immediately after the intervention, a significant reduction in cognitive fusion (p = 0.001, d = 1.78), experiential avoidance (p = 0.001, d = 1.4) and dysfunctional behavioral processes was observed. At the one-month evaluation, participants reported decreased pain (p = 0.001, d = 1.11), anxiety (p = 0.004, d = 0.55) and depression (p = 0.001, d = 0.72). Conclusions: The single-session, process-based approach represents a promising intervention in healthcare contexts, as an integrative part of a multimodal rehabilitation treatment in patients with rheumatic conditions.

There are many recent informative reviews about the skin microbiome in atopic dermatitis (AD) highlighting the prominent role of Staphylococcus aureus (S. aureus) in the pathogenesis of this skin disease. The aim of the current review is to compile and discuss the findings of original studies describing other microbiota alterations contributing to atopic skin inflammation. Moreover, we will discuss the feasibility of using these identified alterations as future diagnostic or therapeutic strategies. Besides S. aureus, there is evidence that other species could also be deleterious in AD, such as the commensal S. epidermidis. Furthermore, microbial metabolites produced by commensal are lost during microbiota dysbiosis; thereby further contributing to AD pathogenesis. Among those, metabolites interacting with the aryl hydrocarbon receptor (AhR), such as metabolites of the tryptophan (Trp) pathway or short chain fatty acids (SCFA) are of special interest since they are able to modulate the transcription of epithelial alarmin genes. Although S. aureus plays a major role in AD pathogenesis, other species and, perhaps more importantly, the metabolites or enzymes they produce may modulate AD pathogenesis. These findings offer future avenues to explore diagnostic or therapeutic approaches for atopic skin inflammation.

ABSTRACTBackgroundFollowing descriptive studies on skin microbiota in health and disease, mechanistic studies on the interplay between skin and microbes are on the rise, for which experimental models are in great demand. Here, we present a novel methodology for microbial colonization of organotypic skin and analysis thereof.ResultsAn inoculation device ensured a standardized application area on thestratum corneumand a homogenous distribution of bacteria, while preventing infection of the basolateral culture medium even during prolonged co-culture periods for up to two weeks at a specific culture temperature and humidity. Hereby, host-microbe interactions and antibiotic interventions could be studied, revealing diverse host responses to various skin-related bacteria and pathogens.ConclusionsOur methodology is easily transferable to a wide variety of organotypic skin or mucosal models and different microbes at every cell culture facility at low costs. We envision that this study will kick-start skin microbiome studies using human organotypic skin cultures, providing a powerful alternative to experimental animal models in pre-clinical research.

Primary cutaneous melanoma (PCM) is the most aggressive skin malignancy, with an increasing incidence and significant mortality. Tumoral invasion, expressed as Breslow thickness, is routinely assessed on hematoxylin and eosin (HE), although this stain may sometimes underestimate the tumoral depth. The aim of this study was to compare the efficiency of the immunohistochemical (IHC) markers S-100, SOX10, Melan-A, and HMB-45 with HE for the evaluation of the Breslow thickness and staging of PCM. This retrospective study included 46 cases of PCM diagnosed between 2015 and 2022; for each case, the Breslow thickness using HE, S-100, SOX10, Melan-A, and HMB-45 was measured and the appropriate T category was recorded. The highest values of the Breslow thickness were observed for S-100. However, S-100, SOX10, and Melan-A provided statistically significant higher values of the Breslow thickness compared to HE, but no difference was noted between HMB-45 and HE. S-100 was most frequently involved in increasing the T category (26.1%), the majority of cases being upstaged from T1a to T1b. The IHC markers S-100, SOX10, and Melan-A contributed to better evaluation of the melanoma invasion, especially in thin melanomas, but their impact on staging and consecutive treatment remains to be confirmed by future studies.

The first sunscreens for the protection of the skin from harmful effects of ultraviolet (UV) radiation, including the early and late effects of sunglight appeared nearly 100 years ago. In recent years the effectiveness of sunscreens in preventing skin ageing, dyspigmentation, DNA damage and photo¬carcinogenesis has been proven. Initially, the main focus aimed at sun protection from ultraviolet B (UVB) radiatio caused damage, later ultraviolet A (UVA) protection attracted attention. We also know that visible and infrared light play a role in skin ageing, so this fact should also be considered when selecting a sunscreen. In this publication, the authors briefly summarize the most important facts about sunscreens, considering on some current issues.

Following descriptive studies on skin microbiota in health and disease, mechanistic studies on the interplay between skin and microbes are on the rise, for which experimental models are in great demand. Here, we present a novel methodology for microbial colonization of organotypic skin and analysis thereof. An inoculation device ensured a standardized application area on the stratum corneum and a homogenous distribution of bacteria, while preventing infection of the basolateral culture medium even during prolonged culture periods for up to 2 weeks at a specific culture temperature and humidity. Hereby, host-microbe interactions and antibiotic interventions could be studied, revealing diverse host responses to various skin-related bacteria and pathogens. Our methodology is easily transferable to a wide variety of organotypic skin or mucosal models and different microbes at every cell culture facility at low costs. We envision that this study will kick-start skin microbiome studies using human organotypic skin cultures, providing a powerful alternative to experimental animal models in pre-clinical research.

Background and Objectives: Rheumatic diseases often exhibit a complex pattern of comorbidities, including the increased occurrence of emotional disorders like anxiety and depression, which are closely related to the presence of chronic pain. Therefore, a multimodal approach is necessary for treatment, targeting both the physical and psychological functioning. Due to the increased burden within the healthcare context that emerged during the post-pandemic period, the need to adjust the content and length of psychological interventions became ubiquitous. In this way, the main objective of this study was to investigate the efficiency of a single-session, process-based psychological intervention for patients with rheumatic conditions and emotional comorbidities in a naturalistic, in-patient setting. Materials and Methods: After the screening, a total of 31 participants (Mage = 58.9, SD = 12.03) completed the single session intervention. The therapeutic protocol relied on a process-based cognitive-behavioural therapy framework aiming to improve cognitive, emotional and behavioural functioning. Assessments were conducted prior to the intervention, post-intervention and one month following the hospitalization. Results: Immediately after the intervention, significant reductions in dysfunctional cognitive and emotional processes, along with the improvement of behavioural strategies were observed. At the one-month telephonic evaluation, participants reported decreased pain, state anxiety and state depression levels. Conclusions: The single-session, process-based approach represents a promising intervention in healthcare contexts, targeting important psychopathological mechanisms in patients with rheumatic conditions. Future studies could clarify the extent to which these outcomes persist over time and their specific associations with anxiety and depressive symptoms, by using more controlled and rigorous trial designs.