Apoptotic Vesicles Derived from Mesenchymal Stem Cells Ameliorate Hypersensitivity Responses via Inducing CD8 T Cells Apoptosis with Calcium Overload and Mitochondrial Dysfunction.

Apoptosis is crucial for maintaining internal homeostasis. Apoptotic vesicles (ApoVs) derived from mesenchymal stem/ stromal cells (MSCs-ApoVs) as natural lipid nanoparticles are attractive candidates for the next generation of immunotherapies. However, the therapeutic potential of MSCs-ApoVs in managing hypersensitivity reactions mediated by CD8 T cells remains elusive.

Endothelial Piezo1 mediates barrier dysfunction and NLRP3 inflammasomes activation in psoriasis.

Psoriasis is a chronic inflammatory skin disease characterized by abnormal dilation of microvessels in the dermal papillary layer. Multiple studies have demonstrated that vascular endothelial cells regulate vascular function rather than merely acting as passive barriers. Piezo1 serves as a critical mechanical switch, sensing mechanical changes induced by vasodilation.

Chronic Cutaneous and Mucosal Mucormycosis: as a Major Pathogenic Fungus.

Chronic cutaneous mucormycosis is a rare condition distinct from the acute form, characterized by a prolonged, indolent course and varied clinical presentations. This study presents a 5-year experience from a tertiary dermato-mycology clinic, identifying six cases, the majority of whom were immunocompetent, with trauma history reported in four patients. The median duration from symptom onset to diagnosis was 60 months.

Targeting the Galectin-7/TRPM2/Zn/DRP-1 Signaling Pathway: A Potential Therapeutic Intervention in the Pathogenesis of SJS/TEN.

Background: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) represent a spectrum of severe drug-induced cutaneous reactions. These conditions are characterized by widespread and confluent keratinocyte apoptosis, which differentiates them from erythema multiforme (EM). Mounting evidence has implicated the mitochondrial-dependent apoptosis pathway in the pathogenesis of SJS/TEN, but the potential roles and specific mechanisms of these pathways in SJS/TEN remain largely unexplored.

Exosomal mediated lipid metabolism, ferritinophagy and CoQ-dependent pathway contributes to the ferroptosis of keratinocyte in SJS/TEN.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) manifest life-threatening cutaneous adverse drug reactions characterized by keratinocyte death. Previous studies have indicated that apoptosis and necroptosis are implicated in SJS/TEN pathogeneses. However, other forms of cell death involved in this process remain unidentified.

Association between non-scarring alopecia and hypothyroidism: a bidirectional two-sample Mendelian randomization study.

Background: Non-scarring alopecia is typically represented by two main types: alopecia areata (AA) and androgenetic alopecia (AGA). While previous observational studies have indicated a link between non-scarring alopecia and hypothyroidism, the precise causal relationship remains uncertain. To determine the potential links between non-scarring alopecia and hypothyroidism, we conducted a bidirectional two-sample Mendelian randomization (MR) analysis.

Formylpeptide receptor 1 contributes to epidermal barrier dysfunction-induced skin inflammation through NOD-like receptor C4-dependent keratinocyte activation.

Background: Skin barrier dysfunction may both initiate and aggravate skin inflammation. However, the mechanisms involved in the inflammation process remain largely unknown.

Objectives: We sought to determine how skin barrier dysfunction enhances skin inflammation and molecular mechanisms.

CREB1-driven CXCR4 neutrophils promote skin inflammation in mouse models and human patients.

Neutrophils have a pathogenic function in inflammation via releasing pro-inflammatory mediators or neutrophil extracellular traps (NETs). However, their heterogeneity and pro-inflammatory mechanisms remain unclear. Here, we demonstrate that CXCR4 neutrophils accumulate in the blood and inflamed skin in human psoriasis, and correlate with disease severity.

Assessment of relationships between bullous pemphigoid and neurological diseases: A bidirectional two-sample Mendelian randomization study.

Bullous pemphigoid (BP) is the most prevalent autoimmune vesiculobullous skin illness that tends to affect the elderly. Growing evidence has hinted a correlation between BP and neurological diseases. However, existing observational studies contained inconsistent results, and the causality and direction of their relationship remain poorly understood.

An IGFBP7hi endothelial cell subset drives T cell extravasation in psoriasis via endothelial glycocalyx degradation.

Dysfunction of vascular endothelial cells (ECs) facilitates imbalanced immune responses and tissue hyperinflammation. However, the heterogeneous functions of skin ECs and their underlying mechanism in dermatoses remain to be determined. Here, focusing on the pathogenic role of skin ECs in psoriasis, we characterized the molecular and functional heterogeneity of skin ECs from healthy individuals and psoriasis patients at the single-cell level.

A population of dermal Langerin dendritic cells promote the inflammation in mouse model of atopic dermatitis.

Cutaneous dendritic cells (DCs) have been implicated in the pathogenesis of atopic dermatitis (AD). However, the specific role of different subsets of DCs has not been well defined. This study aimed to investigate the contributions of Langerhans cells (LCs), resident dermal Langerin DCs (r-Langerin dDCs), and newly infiltrated inflammatory dermal Langerin DCs (i-Langerin dDCs) in an AD mouse model induced by the topical application of MC903.

A dysregulated sebum-microbial metabolite-IL-33 axis initiates skin inflammation in atopic dermatitis.

Microbial dysbiosis in the skin has been implicated in the pathogenesis of atopic dermatitis (AD); however, whether and how changes in the skin microbiome initiate skin inflammation, or vice versa, remains poorly understood. Here, we report that the levels of sebum and its microbial metabolite, propionate, were lower on the skin surface of AD patients compared with those of healthy individuals. Topical propionate application attenuated skin inflammation in mice with MC903-induced AD-like dermatitis by inhibiting IL-33 production in keratinocytes, an effect that was mediated through inhibition of HDAC and regulation of the AhR signaling pathway.

Chemical peeling with 35% glycolic acid for the treatment of disseminated facial verruca plana: A randomized, split-face, evaluator-blinded trial.

Disseminated facial verruca plana is a chronic disorder that causes significant psychological distress. However, safe and effective treatment is lacking. This study aimed to explore the efficacy and safety of 35% glycolic acid (GA) for the treatment of disseminated facial verruca plana.

Neutrophils and their extracellular traps impair ablative fractional carbon dioxide laser-induced dermal remolding in mice.

Objectives: Ablative fractional CO laser (AFL) therapy is an effective intervention to induce dermal remodeling. AFL treatment of the skin triggers the recruitment of immune cells, with neutrophils dominating the early phase. However, the role of recruited neutrophils in AFL-induced microinjuries and their subsequent dermal remodeling capacity remains elusive.

Keratin 17 Promotes T Cell Response in Allergic Contact Dermatitis by Upregulating C-C Motif Chemokine Ligand 20.

Allergic contact dermatitis (ACD) is a delayed-type hypersensitivity response to skin contact allergens in which keratinocytes are critical in the initiation of early responses. Keratin 17 (K17) is a cytoskeletal protein inducible under stressful conditions and regulates multiple cellular processes, especially in skin inflammatory diseases; however, knowledge regarding its contribution to ACD pathogenesis remains ill defined. In the present study, we clarified the proinflammatory role of K17 in an oxazolone (OXA)-induced contact hypersensitivity (CHS) murine model and identified the underlying molecular mechanisms.

Keratin 17 Is Required for Lipid Metabolism in Keratinocytes and Benefits Epidermal Permeability Barrier Homeostasis.

The epidermal barrier refers to the stratum corneum, the uppermost layer of the skin, and constitutes the first line of defense against invasion by potentially harmful pathogens, diminishes -epidermal water loss, and plays a crucial role in the maintenance of skin homeostasis. Keratin 17 (K17) is a type I epithelial keratin with multiple functions, including in skin inflammation, epithelial cell growth, protein synthesis, and tumorigenesis. However, the relationship between K17 and the skin barrier has yet to be systematically investigated.

Cyclin-Dependent Kinase 7 Promotes Th17/Th1 Cell Differentiation in Psoriasis by Modulating Glycolytic Metabolism.

Excessive activation of CD4 T cells and T helper type (Th) 17/Th1 cell differentiation are critical events in psoriasis pathogenesis, but the associated molecular mechanism is still unclear. Here, using quantitative proteomics analysis, we found that cyclin-dependent kinase 7 (CDK7) expression was markedly increased in CD4 T cells from patients with psoriasis compared with healthy controls and was positively correlated with psoriasis severity. Meanwhile, genetic or pharmacological inhibition of CDK7 ameliorated the severity of psoriasis in the imiquimod-induced psoriasis-like mouse model and suppressed CD4 T-cell activation as well as Th17/Th1 cell differentiation in vivo and in vitro.

Single-cell transcriptome profiling reveals vascular endothelial cell heterogeneity in human skin.

Vascular endothelial cells (ECs) are increasingly recognized as active players in intercellular crosstalk more than passive linings of a conduit for nutrition delivery. Yet, their functional roles and heterogeneity in skin remain uncharacterized. We have used single-cell RNA sequencing (scRNA-seq) as a profiling strategy to investigate the tissue-specific features and intra-tissue heterogeneity in dermal ECs at single-cell level.

Plasma exosomal regulates mitochondria-dependent keratinocyte apoptosis by targeting XIAP in severe drug-induced skin reactions.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe drug-induced cutaneous reactions characterized by keratinocyte apoptosis. Exosomes are nanometer-sized membranous vesicles in body fluids. They contain functional proteins, mRNAs, and miRNAs, which induce immune dysfunction and influence disease progression.

Small interfering RNA targeting of keratin 17 reduces inflammation in imiquimod-induced psoriasis-like dermatitis.

Background: Psoriasis is a common chronic inflammatory skin disease with 2% to 3% prevalence worldwide and a heavy social-psychological burden for patients and their families. As the exact pathogenesis of psoriasis is still unknown, the current treatment is far from satisfactory. Thus, there is an urgent need to find a more effective therapy for this disease.