Current acne therapies center on preventing new lesions in patients with acne. These therapies were historically found to be beneficial yet were chosen without knowledge of the specific changes in the skin that favor lesion development. A major challenge in developing new treatments is the incomplete understanding of nonlesional (NL), acne-prone skin’s molecular characteristics. To address this, we compared RNA-sequencing data from NL skin of 49 patients with acne (denoted as NL acne [NLA]) with those from 19 healthy controls with no acne history. We found 77 differentially expressed genes in NLA (log fold change > 1; P < .05), including genes associated with innate immunity and epidermal barrier function. Notably, KRT6C, KRT16, S100A8, S100A9, and lactotransferrin were upregulated, and LCE4A, LCE6A, and CTSE were downregulated. Gene set enrichment analysis revealed that metabolic pathways were enriched in NLA skin, whereas keratinization was negatively enriched. To identify compounds that could shift the gene expression signature of NLA skin toward healthy control skin, we performed connectivity mapping with the Library of Integrated Network-Based Signatures. We identified 187 compounds, particularly mTOR inhibitors, that could potentially normalize the gene expression profile of acne-prone skin to that of healthy skin. Our findings indicate that NLA skin has distinct differences in epidermal differentiation, cellular metabolism, and innate immunity that may promote lesion formation and suggest that mTOR inhibitors could restore NLA skin toward a healthier state, potentially reversing the predisposition to lesion development.
Rationale: Experimental data support the role for C5a–C5aR1 axis activation in bullous pemphigoid. We assessed the efficacy and safety of avdoralimab, a specific anti-C5aR1 mAb, for treating bullous pemphigoid. Methods: We conducted a phase 2 open-labeled randomized multicenter study. Patients with proven bullous pemphigoid were randomized (1:1) to receive superpotent topical steroids alone (group A) or with avdoralimab (group B). All patients received 0.05% clobetasol propionate cream until 15 days after the healing of lesions. Patients in group B additionally received 3 injections of avdoralimab every week for 12 weeks. The main criterion of evaluation was the proportion of patients with initial control of disease activity still in complete clinical remission at 3 months with no relapse during the study period. Results: Fifteen patients were randomized: 7 to group A and 8 to group B. Two patients in group A and in group B achieved control of disease activity at week 4. Only 1 patient was still in complete clinical remission at week 12 in group B, and none was in group A. No adverse event related to the treatment was reported. Conclusions: This proof-of-concept pilot study did not show preliminary signal of additional avdoralimab efficiency compared with superpotent topical steroids alone.
Many aspects of skin biochemistry and physiology are known to vary over the course of the 24-hour day. Traditional approaches to study circadian rhythms in the skin have employed rodents or human subjects, which limit the experimental variables that can be studied. Although explants derived from discarded surgical skin are a commonly used model in the skin biology field, circadian rhythms have yet to be examined ex vivo. In this study, using human panniculectomy skin, we used RT-qPCR to monitor the epidermal expression of 4 core circadian clock genes over the course of 1 day ex vivo. Although significant interindividual variability in overall gene expression profiles was observed, robust circadian oscillations were observed in many of the genes and individual explants. Comparison of our gene expression data with microarray data from 2 previous human-subject studies involving primarily young adult White males revealed both similarities and differences, including greater distribution in the time of day of peak expression in the skin explants. This increased variability appears to be due in part to the increased age and altered sex distribution of the donated skin. Nonetheless, our results indicate that skin explants offer an additional experimental system for studying circadian skin biology.