Dominant dystrophic epidermolysis bullosa is associated with glycolytically active GATA3+ Th2 cells which may contribute to pruritus in lesional skin.

BACKGROUND: Dominant dystrophic epidermolysis bullosa (DDEB) is characterized by trauma-induced blisters and, in some individuals, intense pruritus. Precisely what causes itch in DDEB and optimal ways to reduce it have not been fully determined. OBJECTIVE: To characterize DDEB skin transcriptomes to identify therapeutic targets to reduce pruritus in patients. METHODS: We evaluated affected and unaffected skin biopsy samples from 6 DDEB subjects (all with the very itchy pruriginosa subtype), and 4 healthy individuals using bulk RNA-seq. Single-cell transcriptomes of affected (n=2) and unaffected (n=1) DDEB and healthy skin (n=2) were obtained. Dupilumab treatment was provided for three patients. RESULTS: The skin bulk transcriptome showed significant enrichment of Th1/2 and Th17 pathways in affected DDEB skin compared with non-lesional DDEB and healthy skin. Single-cell transcriptomics showed an association of glycolytically active GATA3+ Th2 cells in affected DDEB skin. Treatment with dupilumab in three people with DDEB led to significantly reduced VAS itch scores after 12 weeks (mean VAS=3.83) compared to pre-treatment (mean VAS=7.83). Bulk RNA-seq and qPCR showed that healthy skin and dupilumab-treated epidermolysis bullosa (EB) pruriginosa skin show very similar transcriptomic profiles, and reduced Th1/2 and Th17 pathway enrichment. CONCLUSIONS: Single-cell RNA-seq helps define an enhanced DDEB-associated Th2 profile and rationalizes drug repurposing of anti-Th2 drugs in treating DDEB pruritus.

Tofacitinib ameliorates skin inflammation in a case of severe autosomal recessive congenital ichthyosis.

Autosomal recessive congenital ichthyosis (ARCI) is a genetically heterogeneous disorder manifesting aberrant skin scaling and increased transepidermal water loss (TEWL). Current treatments for ARCI are limited and sub-optimal. We studied a 27-year-old man with ARCI resulting from a homozygous missense variant in TGM1 (transglutaminase 1). RNA-sequencing of lesional skin revealed aberrant JAK-STAT signalling, providing a rationale for innovative treatment with a Janus kinase inhibitor. We prescribed oral tofacitinib (11 mg daily) for 26 weeks. Rapid improvements in erythema and fissuring manifested within the first month. Sustained reductions in 5-D itch scale and Dermatology Life Quality Index (DLQI) scores were also observed. TEWL decreased for the first 10 weeks but increased thereafter. Tofacitinib down-regulated inflammatory genes and pathways, while enhancing skin barrier markers. Moreover, TGM1 distribution was normalized although enzymatic activity remained deficient. This study suggests that oral tofacitinib may be a useful therapy to consider in patients with ARCI.

Self-improving dystrophic epidermolysis bullosa with a novel heterozygous missense variant in the COL7A1 gene in a Taiwanese family.

Self-improving dystrophic epidermolysis bullosa (DEB) is a genodermatosis that is inherited autosomal dominantly or recessively, and its clinical symptoms may improve or subside spontaneously. Herein, we report a case of self-improving DEB with COL7A1 p.Gly2025Asp variant. The diagnosis was made through histopathological, electron microscopic examination, and genetic testing. The same variant is also noted on his father, who presents with dystrophic toenails without any blisters. This study highlights that idiopathic nail dystrophy could be linked to congenital or hereditary disease. Furthermore, we conducted a review of the literature on the characteristics of reported cases of self-improving DEB with a personal or family history of nail dystrophy. The results supported our findings that nail dystrophy may be the sole manifestation in some family members. We suggest that individuals suffering from idiopathic nail dystrophy may seek genetic counselling when planning pregnancy to early evaluate the potential risk of hereditary diseases.

Histone Trimethylations and HDAC5 Regulate Spheroid Subpopulation and Differentiation Signaling of Human Adipose-Derived Stem Cells.

Human adipose-derived stem cells (ASCs) have shown immense potential for regenerative medicine. Our previous work demonstrated that chitosan nano-deposited surfaces induce spheroid formation and differentiation of ASCs for treating sciatic nerve injuries. However, the underlying cell fate and differentiation mechanisms of ASC-derived spheroids remain unknown. Here, we investigate the epigenetic regulation and signaling coordination of these therapeutic spheroids. During spheroid formation, we observed significant increases in histone 3 trimethylation at lysine 4 (H3K4me3), lysine 9 (H3K9me3), and lysine 27 (H3K27me3), accompanied by increased histone deacetylase (HDAC) activities and decreased histone acetyltransferase activities. Additionally, HDAC5 translocated from the cytoplasm to the nucleus, along with increased nuclear HDAC5 activities. Utilizing single-cell RNA sequencing (scRNA-seq), we analyzed the chitosan-induced ASC spheroids and discovered distinct cluster subpopulations, cell fate trajectories, differentiation traits, and signaling networks using the 10x Genomics platform, R studio/language, and the Ingenuity Pathway Analysis (IPA) tool. Specific subpopulations were identified within the spheroids that corresponded to a transient reprogramming state (Cluster 6) and the endpoint cell state (Cluster 3). H3K4me3 and H3K9me3 were discovered as key epigenetic regulators by IPA to initiate stem cell differentiation in Cluster 6 cells, and confirmed by qPCR and their respective histone methyltransferase inhibitors: SNDX-5613 (a KMT2A inhibitor for H3K4me3) and SUVi (an SUV39H1 inhibitor for H3K9me3). Moreover, H3K9me3 and HDAC5 were involved in regulating downstream signaling and neuronal markers during differentiation in Cluster 3 cells. These findings emphasize the critical role of epigenetic regulation, particularly H3K4me3, H3K9me3, and HDAC5, in shaping stem cell fate and directing lineage-specific differentiation.

TEM1/endosialin/CD248 promotes pathologic scarring and TGF-ß activity through its receptor stability in dermal fibroblasts.

BACKGROUND: Pathologic scars, including keloids and hypertrophic scars, represent a common form of exaggerated cutaneous scarring that is difficult to prevent or treat effectively. Additionally, the pathobiology of pathologic scars remains poorly understood. We aim at investigating the impact of TEM1 (also known as endosialin or CD248), which is a glycosylated type I transmembrane protein, on development of pathologic scars. METHODS: To investigate the expression of TEM1, we utilized immunofluorescence staining, Western blotting, and single-cell RNA-sequencing (scRNA-seq) techniques. We conducted in vitro cell culture experiments and an in vivo stretch-induced scar mouse model to study the involvement of TEM1 in TGF-ß-mediated responses in pathologic scars. RESULTS: The levels of the protein TEM1 are elevated in both hypertrophic scars and keloids in comparison to normal skin. A re-analysis of scRNA-seq datasets reveals that a major profibrotic subpopulation of keloid and hypertrophic scar fibroblasts greatly expresses TEM1, with expression increasing during fibroblast activation. TEM1 promotes activation, proliferation, and ECM production in human dermal fibroblasts by enhancing TGF-ß1 signaling through binding with and stabilizing TGF-ß receptors. Global deletion of Tem1 markedly reduces the amount of ECM synthesis and inflammation in a scar in a mouse model of stretch-induced pathologic scarring. The intralesional administration of ontuxizumab, a humanized IgG monoclonal antibody targeting TEM1, significantly decreased both the size and collagen density of keloids. CONCLUSIONS: Our data indicate that TEM1 plays a role in pathologic scarring, with its synergistic effect on the TGF-ß signaling contributing to dermal fibroblast activation. Targeting TEM1 may represent a novel therapeutic approach in reducing the morbidity of pathologic scars.

Profibrotic Subsets of SPP1+ Macrophages and POSTN+ Fibroblasts Contribute to Fibrotic Scarring in Acne Keloidalis.

Acne keloidalis is a primary scarring alopecia characterized by longstanding inflammation in the scalp causing keloid-like scar formation and hair loss. Histologically, acne keloidalis is characterized by mixed leukocytic infiltrates in the acute stage followed by a granulomatous reaction and extensive fibrosis in the later stages. To further explore its pathogenesis, bulk RNA sequencing, single-cell RNA sequencing, and spatial transcriptomics were applied to occipital scalp biopsy specimens of lesional and adjacent no-lesional skin in patients with clinically active disease. Unbiased clustering revealed 19 distinct cell populations, including 2 notable populations: POSTN+ fibroblasts with enriched extracellular matrix signatures and SPP1+ myeloid cells with an M2 macrophage phenotype. Cell communication analyses indicated that fibroblasts and myeloid cells communicated by SPP1 signaling networks in lesional skin. A reverse transcriptomics in silico approach identified corticosteroids as possessing the capability to reverse the gene expression signatures of SPP1+ myeloid cells and POSTN+ fibroblasts. Intralesional corticosteroid injection greatly reduced SPP1 and POSTN gene expression as well as acne keloidalis disease activity. Spatial transcriptomics and immunofluorescence staining verified microanatomic specificity of SPP1+ myeloid cells and POSTN+ fibroblasts with disease activity. In summary, the communication between POSTN+ fibroblasts and SPP1+ myeloid cells by SPP1 axis may contribute to the pathogenesis of acne keloidalis.

Evaluation of an offline, artificial intelligence system for referable glaucoma screening using a smartphone-based fundus camera: a prospective study.

BACKGROUND/OBJECTIVES: An affordable and scalable screening model is critical for undetected glaucoma. The study evaluated the performance of an offline, smartphone-based AI system for the detection of referable glaucoma against two benchmarks: specialist diagnosis following full glaucoma workup and consensus image grading. SUBJECTS/METHODS: This prospective study (tertiary glaucoma centre, India) included 243 subjects with varying severity of glaucoma and control group without glaucoma. Disc-centred images were captured using a validated smartphone-based fundus camera analysed by the AI system and graded by specialists. Diagnostic ability of the AI in detecting referable Glaucoma (Confirmed glaucoma) and no referable Glaucoma (Suspects and No glaucoma) when compared to a final diagnosis (comprehensive glaucoma workup) and majority grading (image grading) by Glaucoma specialists (pre-defined criteria) were evaluated. RESULTS: The AI system demonstrated a sensitivity and specificity of 93.7% (95% CI: 87.6-96.9%) and 85.6% (95% CI:78.6-90.6%), respectively, in the detection of referable glaucoma when compared against final diagnosis following full glaucoma workup. True negative rate in definite non-glaucoma cases was 94.7% (95% CI: 87.2-97.9%). Amongst the false negatives were 4 early and 3 moderate glaucoma. When the same set of images provided to the AI was also provided to the specialists for image grading, specialists detected 60% (67/111) of true glaucoma cases versus a detection rate of 94% (104/111) by the AI. CONCLUSION: The AI tool showed robust performance when compared against a stringent benchmark. It had modest over-referral of normal subjects despite being challenged with fundus images alone. The next step involves a population-level assessment.

Novel SLC5A6 mutations lead to B lymphocyte maturation defects with metabolic abnormality rescuable by biotin replenishment.

We characterized a family diagnosed with immunodeficiency disease presenting with low immunoglobulin levels and skin dyskeratosis. Exome sequencing revealed compound heterozygous missense variants in SLC5A6, the gene encoding a cellular sodium-dependent multivitamin transporter (SMVT) responsible for transporting vitamins, including biotin (vitamin B7). We showed that the biotin deficiency was caused by the SLC5A6 variants resulting in defective B cell differentiation and antibody deficiency. Altered cellular metabolic profiles, including aberrant mitochondrial respiration and reliance on glycolysis, may underlie the failure in plasma cell maturation. Replenishment of biotin improved plasma cell maturation and recovered the antibody producing activity in the patient and in a CRISPR-Cas9 gene-edited mouse model bearing a patient-specific SLC5A6 variant. Our results demonstrate the critical role of metabolic reprogramming in the maturation of plasma cells and nominate SLC5A6 as a causative gene for immunodeficiency that may be treated by biotin replenishment.

Biocompatible, Antibacterial, and Stable Deep Eutectic Solvent-Based Ionic Gel Multimodal Sensors for Healthcare Applications.

In this study, we investigated a novel approach to fabricate multifunctional ionic gel sensors by using deep eutectic solvents (DESs) as replacements for water. When two distinct DESs were combined, customizable mechanical and conductive properties were created, resulting in improved performance compared with traditional hydrogel-based strain sensors. DES ionic gels possess superior mechanical properties, transparency, biocompatibility, and antimicrobial properties, making them suitable for a wide range of applications such as flexible electronics, soft robotics, and healthcare. We conducted a comprehensive evaluation of the DES ionic gels, evaluating their performance under extreme temperature conditions (-70 to 80 °C), impressive optical transparency (94%), and biocompatibility. Furthermore, a series of tests were conducted to evaluate the antibacterial performance (Escherichia coli) of the DES ionic gels. Their wide strain (1-400%) and temperature (15-50 °C)-sensing ranges demonstrate the versatility and adaptability of DES ionic gels for diverse sensing requirements. The resulting DES ionic gels were successfully applied in human activity and vital sign monitoring, demonstrating their potential for biointegrated sensing devices and healthcare applications. This study offers valuable insights into the development and optimization of hydrogel sensors, particularly for applications that require environmental stability, biocompatibility, and antibacterial performance, thereby paving the way for future advancements in this field.

Loss of fragile WWOX gene leads to senescence escape and genome instability.

Induction of DNA damage response (DDR) to ensure accurate duplication of genetic information is crucial for maintaining genome integrity during DNA replication. Cellular senescence is a DDR mechanism that prevents the proliferation of cells with damaged DNA to avoid mitotic anomalies and inheritance of the damage over cell generations. Human WWOX gene resides within a common fragile site FRA16D that is preferentially prone to form breaks on metaphase chromosome upon replication stress. We report here that primary Wwox knockout (Wwox-/-) mouse embryonic fibroblasts (MEFs) and WWOX-knockdown human dermal fibroblasts failed to undergo replication-induced cellular senescence after multiple passages in vitro. Strikingly, by greater than 20 passages, accelerated cell cycle progression and increased apoptosis occurred in these late-passage Wwox-/- MEFs. These cells exhibited γH2AX upregulation and microsatellite instability, indicating massive accumulation of nuclear DNA lesions. Ultraviolet radiation-induced premature senescence was also blocked by WWOX knockdown in human HEK293T cells. Mechanistically, overproduction of cytosolic reactive oxygen species caused p16Ink4a promoter hypermethylation, aberrant p53/p21Cip1/Waf1 signaling axis and accelerated p27Kip1 protein degradation, thereby leading to the failure of senescence induction in Wwox-deficient cells after serial passage in culture. We determined that significantly reduced protein stability or loss-of-function A135P/V213G mutations in the DNA-binding domain of p53 caused defective induction of p21Cip1/Waf1 in late-passage Wwox-/- MEFs. Treatment of N-acetyl-L-cysteine prevented downregulation of cyclin-dependent kinase inhibitors and induced senescence in Wwox-/- MEFs. Our findings support an important role for fragile WWOX gene in inducing cellular senescence for maintaining genome integrity during DDR through alleviating oxidative stress.

Multiple Itchy Erythematous Papules and Plaques Localized to 1 Shin.

A woman in her 30s presented with progressive, multiple itchy erythematous to violaceous papules and plaques with milia and a few erosions with partially detached epidermis localized to the left shin. What is your diagnosis?

Adipose transcriptome in the scalp of androgenetic alopecia.

Previous studies have shown how adipocytes can modulate the activity of hair follicle stem cells. However, the role of adipocytes in the pathogenesis of androgenetic alopecia (AGA) remains unknown. We aimed to determine signaling pathways related to the adipose tissue changes in the human scalp with AGA through RNA-seq analysis. RNA was isolated from the adipose tissues derived from the bald (frontal) and normal (occipital) scalps of male patients with AGA (n = 4). The pooled RNA extracts from these samples were subjected to RNA sequencing, followed by differential gene expression and pathway analysis. Our gene expression analysis identified 1,060 differentially expressed genes, including 522 upregulated and 538 downregulated genes in the bald AGA scalp. Biological pathways pertaining to either adipose tissue metabolism or the hair cycle were generated in our pathway analysis. Downregulation of the peroxisome proliferator-activated receptor (PPAR) signaling pathway was noted to be significant in the bald scalp. Expression of adipogenic markers (e.g., PPARG, FABP4, PLN1, and ADIPOQ) was also decreased in the bald site. These findings imply that adipogenesis becomes downregulated in AGA, specifically within the bald scalp adipose. Our results lead to the hypothesis that PPARγ-mediated adipogenesis in the scalp adipose, via crosstalk with signaling pathways involved in hair cycling, might play a role in AGA.