Single-cell transcriptomics analysis of bullous pemphigoid unveils immune-stromal crosstalk in type 2 inflammatory disease.

Bullous pemphigoid (BP) is a type 2 inflammation- and immunity-driven skin disease, yet a comprehensive understanding of the immune landscape, particularly immune-stromal crosstalk in BP, remains elusive. Herein, using single-cell RNA sequencing (scRNA-seq) and in vitro functional analyzes, we pinpoint Th2 cells, dendritic cells (DCs), and fibroblasts as crucial cell populations. The IL13-IL13RA1 ligand-receptor pair is identified as the most significant mediator of immune-stromal crosstalk in BP. Notably, fibroblasts and DCs expressing IL13RA1 respond to IL13-secreting Th2 cells, thereby amplifying Th2 cell-mediated cascade responses, which occurs through the specific upregulation of PLA2G2A in fibroblasts and CCL17 in myeloid cells, creating a positive feedback loop integral to immune-stromal crosstalk. Furthermore, PLA2G2A and CCL17 contribute to an increased titer of pathogenic anti-BP180-NC16A autoantibodies in BP patients. Our work provides a comprehensive insight into BP pathogenesis and shows a mechanism governing immune-stromal interactions, providing potential avenues for future therapeutic research.

Targeted serum proteome profiling reveals nicotinamide adenine dinucleotide phosphate (NADPH)-related biomarkers to discriminate linear IgA bullous disorder from dermatitis herpetiformis.

Linear IgA bullous dermatosis (LABD) and dermatitis herpetiformis (DH) represent the major subtypes of IgA mediated autoimmune bullous disorders. We sought to understand the disease etiology by using serum proteomics. We assessed 92 organ damage biomarkers in LABD, DH, and healthy controls using the Olink high-throughput proteomics. The positive proteomic serum biomarkers were used to correlate with clinical features and HLA type. Targeted proteomic analysis of IgA deposition bullous disorders vs. controls showed elevated biomarkers. Further clustering and enrichment analyses identified distinct clusters between LABD and DH, highlighting the involvement of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Comparative analysis revealed biomarkers with distinction between LABD and DH and validated in the skin lesion. Finally, qualitative correlation analysis with DEPs suggested six biomarkers (NBN, NCF2, CAPG, FES, BID, and PXN) have better prognosis in DH patients. These findings provide potential biomarkers to differentiate the disease subtype of IgA deposition bullous disease.

The burden of skin diseases in China: global burden of Disease Study 2019.

Skin diseases continue to affect human health and cause a significant disease burden on the healthcare system.We aimed to report the changing trends in the burden of skin disease in China from 1990 to 2019, Which has an important role in developing targeted prevention strategies. We applied Global Burden of Disease, Injuries, and Risk Factors Study (GBD) 2019 analytical tools to calculate the age-standardized Prevalence and Incidence in 2019, number of years lived with disability (YLDs) and age-standardized YLDs from 1990 to 2019 of skin and subcutaneous diseases, notifiable infectious skin diseases and skin tumors in China. Among the skin and subcutaneous diseases in China in 2019, dermatitis contributed to the greatest YLD (2.17 million, 95% uncertainty interval[UI]: 1.28-3.36). Age-standardized YLD rates for leprosy decreased from 0.09 (95%UI: 0.06-0.13) in 1990 to 0.04 (95%UI: 0.03-0.06) in 2019; the proportional decrease was 55.56% over 30 years. Age-standardized YLDs for HIV and sexually transmitted infections increased by 26% during the same time period. Age-standardized YLDs for non-melanoma skin cancer increased at a much higher rate than melanoma between 1990 and 2019. Dermatitis and scabies continue to have an important role in the burden of skin and subcutaneous disease burden in China. The burden of non-melanoma cell cancer has increased most significantly over the past three decades.

Genetic analysis of different subtypes of Aseptic pustulosis in the Chinese population.

Aseptic pustulosis involves inflammatory skin conditions with non-bacterial pustules on red skin, accompanied by neutrophil and eosinophil infiltration in the epidermis. Dysregulation of the IL-36 pathway leads to neutrophil aggregation and pustule formation. Variants in IL36RN, CARD14, AP1S3, MPO, SERPINA3, and BTN3A3 genes have been identified in GPP in the past. Some patients with ACH, PPP, and AGEP also exhibit mutations in IL36RN, CARD14, and AP1S3 genes, albeit with regional and population-specific variations. This study aims to explore a shared genetic foundation among aseptic pustulosis. We performed Sanger sequencing on six genes in 126 aseptic pustulosis patients. Genetic analysis identified IL36RN variants strongly associated with ACH, AGEP, and SPD. Immunohistochemistry revealed elevated inflammatory cytokines in all subtypes. This study establishes a significant association between IL36RN variants and ACH, AGEP, and SPD, emphasizing the IL-1/IL-36 chemokine-neutrophil axis as a common pathogenic mechanism. Targeting this axis holds promise for therapeutic interventions in aseptic pustulosis.

Tildrakizumab for moderate-to-severe plaque psoriasis in Chinese patients: A 12-week randomized placebo-controlled phase III trial with long-term extension.

BACKGROUND: There is a need for effective and safe therapies for psoriasis that provide sustained benefits. The aim of this study was to assess the efficacy and safety of tildrakizumab, an anti-interleukin-23p19 monoclonal antibody, for treating moderate-to-severe plaque psoriasis in Chinese patients. METHODS: In this multi-center, double-blind, phase III trial, patients with moderate-to-severe plaque psoriasis were enrolled and randomly assigned (1:1) to receive subcutaneous tildrakizumab 100 mg or placebo at weeks 0 and 4. Patients initially assigned to placebo were switched to receive tildrakizumab at weeks 12, 16, and every 12 weeks thereafter. Patients in the tildrakizumab group continued with tildrakizumab at week 16, and every 12 weeks until week 52. The primary endpoint was the Psoriasis Area and Severity Index (PASI 75) response rate at week 12. RESULTS: At week 12, tildrakizumab demonstrated significantly higher PASI 75 response rates (66.4% [73/110] vs. 12.7% [14/110]; difference, 51.4% [95% confidence interval (CI), 40.72, 62.13]; P <0.001) and Physician's Global Assessment (60.9% [67/110] vs. 10.0% [11/110]; difference, 49.1% [95% CI, 38.64, 59.62]; P <0.001) compared to placebo. PASI 75 response continued to improve over time in both tildrakizumab and placebo-switching to tildrakizumab groups, reaching maximal efficacy after 28 weeks (86.8% [92/106] vs . 82.4% [89/108]) and maintained up to 52 weeks (91.3% [95/104] vs . 87.4% [90/103]). Most treatment-emergent adverse events were mild and not related to tildrakizumab. CONCLUSION: Tildrakizumab demonstrated durable efficacy through week 52 and was well tolerated in Chinese patients with moderate-to-severe plaque psoriasis. TRIAL REGISTRATION: ClinicalTrials.gov , NCT05108766.

Efficacy and safety of CM310 in moderate-to-severe atopic dermatitis: A multicenter, randomized, double-blind, placebo-controlled phase 2b trial.

BACKGROUND: Atopic dermatitis (AD) affects approximately 10% of adults worldwide. CM310 is a humanized monoclonal antibody targeting interleukin-4 receptor alpha that blocks interleukin-4 and interleukin-13 signaling. This trial aimed to evaluate the efficacy and safety of CM310 in Chinese adults with moderate-to-severe AD. METHODS: This multicenter, randomized, double-blind, placebo-controlled, phase 2b trial was conducted in 21 medical institutions in China from February to November 2021. Totally 120 eligible patients were enrolled and randomized (1:1:1) to receive subcutaneous injections of 300 mg CM310, 150 mg CM310, or placebo every 2 weeks for 16 weeks, followed by an 8-week follow-up period. The primary endpoint was the proportion of patients achieving ≥75% improvement in the Eczema Area and Severity Index (EASI-75) score from baseline at week 16. Safety and pharmacodynamics were also studied. RESULTS: At week 16, the proportion of EASI-75 responders from baseline was significantly higher in the CM310 groups (70% [28/40] for high-dose and 65% [26/40] for low-dose) than that in the placebo group (20%[8/40]). The differences in EASI-75 response rate were 50% (high vs . placebo, 95% CI 31%-69%) and 45% (low vs . placebo, 95% CI 26%-64%), with both P values <0.0001. CM310 at both doses also significantly improved the EASI score, Investigator's Global Assessment score, daily peak pruritus Numerical Rating Scale, AD-affected body surface area, and Dermatology Life Quality Index compared with placebo. CM310 treatment reduced levels of thymus and activation-regulated chemokine, total immunoglobulin E, lactate dehydrogenase, and blood eosinophils. The incidence of treatment-emergent adverse events (TEAEs) was similar among all three groups, with the most common TEAEs reported being upper respiratory tract infection, atopic dermatitis, hyperlipidemia, and hyperuricemia. No severe adverse events were deemed to be attributed to CM310. CONCLUSION: CM310 at 150 mg and 300 mg every 2 weeks demonstrated significant efficacy and was well-tolerated in adults with moderate-to-severe AD.

CYBB-Mediated Ferroptosis Associated with Immunosuppression in Mycobacterium leprae-Infected Monocyte-Derived Macrophages.

Mycobacterium leprae-infected macrophages preferentially exhibit the regulatory M2 phenotype in vitro, which helps the immune escape unabated growth of M leprae in host cells. The mechanism that triggers macrophage polarization is still unknown. In this study, we performed single-cell RNA sequencing to determine the initial responses of human monocyte-derived macrophages against M leprae infection of 4 healthy individuals and found an increase in a major alternative-activated macrophage type that overexpressed NEAT1, CCL2, and CD163. Importantly, further functional analysis showed that ferroptosis was positively correlated with M2 polarization of macrophages, and in vitro experiments have shown that inhibition of ferroptosis promotes the survival of M leprae within macrophages. In addition, further joint analysis of our results with mutisequencing data from patients with leprosy and in vitro validation identified that CYBB was the pivotal molecule for ferroptosis that could promote the M2 polarization of M leprae-infected macrophages, resulting in the immune escape and unabated growth of pathogenic bacteria. Overall, our results suggest that M leprae facilitated its survival by inducing CYBB-mediated macrophage ferroptosis leading to its alternative activation and might reveal the potential for a new therapeutic strategy of leprosy.

Photodynamic therapy and CO2 fractional laser combination therapy for verruca vulgaris caused by Koebner phenomenon - Two case reports.

Verruca vulgaris, caused by the human papillomavirus (HPV), can profoundly impact an individual's quality of life and necessitate therapeutic intervention. The challenges associated with treating verruca vulgaris are particularly noteworthy when they manifest as the Koebner phenomenon (KP). In this report, we present two cases of verruca vulgaris that developed KP following cryotherapy. Some studies have suggested that pretreatment with laser therapy enhances the efficacy of Photodynamic Therapy (PDT). Given the inefficacy of cryotherapy and the emergence of KP in our patients, we opted for a treatment approach that combined PDT with CO2 fractional laser (CO2FL), resulting in complete resolution without any notable adverse effects or recurrence during the follow-up period. Our cases underscore the importance of considering KP when verruca vulgaris exhibit enlargement and proliferation post-cryotherapy. Furthermore, this combined treatment modality demonstrates its effectiveness and safety. Additionally, our experience highlights the need for a large-scale study to determine the optimal photosensitizer concentration for the treatment of thick, enlarged verruca vulgaris.

Genome-wide meta-analysis and fine-mapping prioritize potential causal variants and genes related to leprosy.

To date, genome-wide association studies (GWASs) have discovered 35 susceptible loci of leprosy; however, the cumulative effects of these loci can only partially explain the overall risk of leprosy, and the causal variants and genes within these loci remain unknown. Here, we conducted out new GWASs in two independent cohorts of 5007 cases and 4579 controls and then a meta-analysis in these newly generated and multiple previously published (2277 cases and 3159 controls) datasets were performed. Three novel and 15 previously reported risk loci were identified from these datasets, increasing the known leprosy risk loci of explained genetic heritability from 23.0 to 38.5%. A comprehensive fine-mapping analysis was conducted, and 19 causal variants and 14 causal genes were identified. Specifically, manual checking of epigenomic information from the Epimap database revealed that the causal variants were mainly located within the immune-relevant or immune-specific regulatory elements. Furthermore, by using gene-set, tissue, and cell-type enrichment analyses, we highlighted the key roles of immune-related tissues and cells and implicated the PD-1 signaling pathways in the pathogenetic mechanism of leprosy. Collectively, our study identified candidate causal variants and elucidated the potential regulatory and coding mechanisms for genes associated with leprosy.

HLA-C*15:02 and epidermal growth factor receptor inhibitor-induced erosive pustular dermatosis of the scalp.

Epidermal growth factor receptor inhibitors (EGFRIs) are widely used to treat various types of malignancies. One of the common adverse reactions is cutaneous toxicity, mostly presenting as acneiform eruptions, paronychia and xerosis. Erosive pustular dermatosis of the scalp (EPDS) is a rare cutaneous adverse reaction that develops during treatment with EGFRIs. The pathogenesis of EGFRI-induced EPDS is poorly understood. Here we present three cases of EPDS induced by EGFRIs. The proteins LTA4H (leukotriene A-4 hydrolase), METAP1 (methionine aminopeptidase 1), BID (BH3-interacting domain death agonist), SMAD1 (mothers against decapentaplegic homologue), PRKRA (interferon-inducible double-stranded RNA-dependent protein kinase activator A), YES1 (tyrosine-protein kinase Yes) and EGFL7 (epidermal growth factor-like protein 7) were significantly upregulated in EGFRI-stimulated peripheral blood mononuclear cell cultures, and validated in the lesions. All of the proteins colocalized with CD4+ and CD8+ T-cell expression. Next-generation-based human leucocyte antigen (HLA) typing showed all patients carried HLA-C*15:02, and modelling studies showed that afatinib and erlotinib bound well within the E/F binding pockets of HLA-C*15:02. Moreover, T cells were preferentially activated by EGFRIs in individuals carrying HLA-C*15:02. The case series revealed that EGFRI-induced EPDS may be mediated by drug-specific T cells.