Early-life inflammation primes a T helper 2 cell-fibroblast niche in skin.

Inflammation early in life can prime the local immune milieu of peripheral tissues, which can cause lasting changes in immunological tone that confer disease protection or susceptibility1. The cellular and molecular mechanisms that prompt changes in immune tone in many nonlymphoid tissues remain largely unknown. Here we find that time-limited neonatal inflammation induced by a transient reduction in neonatal regulatory T cells causes a dysregulation of subcutaneous tissue in mouse skin. This is accompanied by the selective accumulation of type 2 helper T (TH2) cells within a distinct microanatomical niche. TH2 cells are maintained into adulthood through interactions with a fibroblast population in skin fascia that we refer to as TH2-interacting fascial fibroblasts (TIFFs), which expand in response to TH2 cytokines to form subcutaneous fibrous bands. Activation of the TH2-TIFF niche due to neonatal inflammation primes the skin for altered reparative responses to wounding. Furthermore, we identify fibroblasts in healthy human skin that express the TIFF transcriptional signature and detect these cells at high levels in eosinophilic fasciitis, an orphan disease characterized by inflammation and fibrosis of the skin fascia. Taken together, these data define a previously unidentified TH2 cell niche in skin and functionally characterize a disease-associated fibroblast population. The results also suggest a mechanism of immunological priming whereby inflammation early in life creates networks between adaptive immune cells and stromal cells to establish an immunological set-point in tissues that is maintained throughout life.

Layilin Anchors Regulatory T Cells in Skin.

Regulatory T cells (Tregs) reside in nonlymphoid tissues where they carry out unique functions. The molecular mechanisms responsible for Treg accumulation and maintenance in these tissues are relatively unknown. Using an unbiased discovery approach, we identified LAYN (layilin), a C-type lectin-like receptor, to be preferentially and highly expressed on a subset of activated Tregs in healthy and diseased human skin. Expression of layilin on Tregs was induced by TCR-mediated activation in the presence of IL-2 or TGF-ß. Mice with a conditional deletion of layilin in Tregs had reduced accumulation of these cells in tumors. However, these animals somewhat paradoxically had enhanced immune regulation in the tumor microenvironment, resulting in increased tumor growth. Mechanistically, layilin expression on Tregs had a minimal effect on their activation and suppressive capacity in vitro. However, expression of this molecule resulted in a cumulative anchoring effect on Treg dynamic motility in vivo. Taken together, our results suggest a model whereby layilin facilitates Treg adhesion in skin and, in doing so, limits their suppressive capacity. These findings uncover a unique mechanism whereby reduced Treg motility acts to limit immune regulation in nonlymphoid organs and may help guide strategies to exploit this phenomenon for therapeutic benefit.

Impact of second-opinion dermatopathology reviews on surgical management of malignant neoplasms.

BACKGROUND: Second-opinion review is linked to error reduction and treatment changes in anatomic pathology. OBJECTIVE: We sought to establish the rate of diagnostic discrepancy identified by second-opinion dermatopathologic review and the effect on surgical treatment. METHODS: Cases referred for treatment of a malignant neoplasm diagnosed by an outside pathologist were reviewed. The external and internal second-opinion dermatopathologic reports were compared. Discordance in diagnosis, subtype, and treatment change owing to second-opinion review was recorded. The referring pathologist's level of dermatopathologic training was also documented. RESULTS: A total of 358 cases were included. Dermatopathologic second-opinion diagnosis was discordant with the outside diagnosis in 37 of 358 cases (10.3%). In 32 of 358 cases (8.9%), second-opinion review resulted in a change in treatment, with 28 of 32 (87.5%) of these changes resulting in cancelled surgery. Dermatologists without dermatopathologic fellowship training had the highest rate of discordant diagnoses compared with pathologists and dermatopathologists. LIMITATIONS: This was a retrospective study at a tertiary care facility. CONCLUSION: Second-opinion dermatopathologic review is associated with identification of discordant diagnoses and a substantial influence on treatment, with both cancellation of surgery and augmented management. Secondary pathologic review should be considered in high-volume surgical practices.

Sebaceous carcinoma: evidence-based clinical practice guidelines.

Sebaceous carcinoma usually occurs in adults older than 60 years, on the eyelid, head and neck, and trunk. In this Review, we present clinical care recommendations for sebaceous carcinoma, which were developed as a result of an expert panel evaluation of the findings of a systematic review. Key conclusions were drawn and recommendations made for diagnosis, first-line treatment, radiotherapy, and post-treatment care. For diagnosis, we concluded that deep biopsy is often required; furthermore, differential diagnoses that mimic the condition can be excluded with special histological stains. For treatment, the recommended first-line therapy is surgical removal, followed by margin assessment of the peripheral and deep tissue edges; conjunctival mapping biopsies can facilitate surgical planning. Radiotherapy can be considered for cases with nerve or lymph node involvement, and as the primary treatment in patients who are ineligible for surgery. Post-treatment clinical examination should occur every 6 months for at least 3 years. No specific systemic therapies for advanced disease can be recommended, but targeted therapies and immunotherapies are being developed.

The distribution of cutaneous metastases correlates with local immunologic milieu.

BACKGROUND: Metastases to the skin are found with increased frequency at certain sites, such as the scalp, but the biological factors that influence this distribution are not understood. OBJECTIVE: We aimed to compare the proportional frequency of metastases at various cutaneous locations with the immunologic microenvironments at those sites. METHODS: We retrospectively identified all biopsy specimens of cutaneous metastases diagnosed at our institution from 1991 to 2014 (n = 1984) and mapped their anatomic distribution while controlling for regional surface area. Using a separate, mapped cohort of normal-appearing skin samples (n = 140), we measured the density of regulatory T cells, CD4(+) effector T cells, and CD8(+) T cells by flow cytometry. RESULTS: Per unit surface area, cutaneous metastases arise most commonly on the head and neck, followed by the trunk, upper extremities, and lower extremities, respectively. Sites with more frequent metastases tend to contain a greater density of regulatory T cells and a lower proportion of CD8(+) T cells (P < .05). LIMITATIONS: Immunologic factors were only assessed in control tissue and were not measured from patients with metastatic disease in this correlative single-center study. CONCLUSION: The distribution of cutaneous metastases follows the distribution of regulatory and effector T cells in skin. Further studies are required to prove a mechanistic association between local immunologic factors and the development of cutaneous metastases.

Loss-of-function mutations in Notch receptors in cutaneous and lung squamous cell carcinoma.

Squamous cell carcinomas (SCCs) are one of the most frequent forms of human malignancy, but, other than TP53 mutations, few causative somatic aberrations have been identified. We identified NOTCH1 or NOTCH2 mutations in ~75% of cutaneous SCCs and in a lesser fraction of lung SCCs, defining a spectrum for the most prevalent tumor suppressor specific to these epithelial malignancies. Notch receptors normally transduce signals in response to ligands on neighboring cells, regulating metazoan lineage selection and developmental patterning. Our findings therefore illustrate a central role for disruption of microenvironmental communication in cancer progression. NOTCH aberrations include frameshift and nonsense mutations leading to receptor truncations as well as point substitutions in key functional domains that abrogate signaling in cell-based assays. Oncogenic gain-of-function mutations in NOTCH1 commonly occur in human T-cell lymphoblastic leukemia/lymphoma and B-cell chronic lymphocytic leukemia. The bifunctional role of Notch in human cancer thus emphasizes the context dependency of signaling outcomes and suggests that targeted inhibition of the Notch pathway may induce squamous epithelial malignancies.

Rosacea Core Domain Set for Clinical Trials and Practice: A Consensus Statement.

Importance: Inconsistent reporting of outcomes in clinical trials of rosacea is impeding and likely preventing accurate data pooling and meta-analyses. There is a need for standardization of outcomes assessed during intervention trials of rosacea. Objective: To develop a rosacea core outcome set (COS) based on key domains that are globally relevant and applicable to all demographic groups to be used as a minimum list of outcomes for reporting by rosacea clinical trials, and when appropriate, in clinical practice. Evidence Review: A systematic literature review of rosacea clinical trials was conducted. Discrete outcomes were extracted and augmented through discussions and focus groups with key stakeholders. The initial list of 192 outcomes was refined to identify 50 unique outcomes that were rated through the Delphi process Round 1 by 88 panelists (63 physicians from 17 countries and 25 patients with rosacea in the US) on 9-point Likert scale. Based on feedback, an additional 11 outcomes were added in Round 2. Outcomes deemed to be critical for inclusion (rated 7-9 by ≥70% of both groups) were discussed in consensus meetings. The outcomes deemed to be most important for inclusion by at least 85% of the participants were incorporated into the final core domain set. Findings: The Delphi process and consensus-building meetings identified a final core set of 8 domains for rosacea clinical trials: ocular signs and symptoms; skin signs of disease; skin symptoms; overall severity; patient satisfaction; quality of life; degree of improvement; and presence and severity of treatment-related adverse events. Recommendations were also made for application in the clinical setting. Conclusions and Relevance: This core domain set for rosacea research is now available; its adoption by researchers may improve the usefulness of future trials of rosacea therapies by enabling meta-analyses and other comparisons across studies. This core domain set may also be useful in clinical practice.

Tobacco smoking and dermatologic surgery.

BACKGROUND: Cigarette smoking is the leading cause of preventable death and a major public health concern. Numerous clinical and experimental studies have examined the effect of nicotine on wound healing and surgical procedures, but there are limited published reports in the dermatologic surgery literature. OBJECTIVE: This article seeks to develop evidence-based recommendations regarding the effect of tobacco use in patients undergoing dermatologic surgery procedures. METHODS: This article reviews the existing published English-language literature pertaining to the effects of tobacco on wound healing and surgical complications. RESULTS: Tobacco use is associated with a higher incidence of postoperative complications including wound dehiscence, flap or graft necrosis, prolonged healing time, and infections. LIMITATIONS: This review article only summarizes past reports and studies. CONCLUSION: Recommendations for smoking cessation before dermatologic surgery are provided based on the available data.

Accuracy and completeness of patient information in organic World-Wide Web search for Mohs surgery: a prospective cross-sectional multirater study using consensus criteria.

BACKGROUND: Many patients obtain medical information from the Internet. Inaccurate information affects patient care and perceptions. OBJECTIVE: To assess the accuracy and completeness of information regarding Mohs micrographic surgery (MMS) on the Internet. METHODS: Prospective cross-sectional Internet-based study reviewing 30 consecutive organic results from three U.S. urban areas on "Mohs surgery" using Google. Text was assessed using a consensus-derived rating scale that quantified necessary and additional or supplementary information about MMS, as well as wrong information. Websites were classified according to type of sponsor. RESULTS: Ninety-one percent of sites conveyed basic information about MMS. There was variation in the mean amount of additional information items (range 0-9) according to website type: 8.4, medical societies; 6.7, academic practices; 5.9, web-based medical information resources; 4.7, private practices; and 4.4, other (p < .001). Cumulatively, academic practices and professional societies (mean 7.42) provided more additional information than private practices and web-based sources (mean 5.11, p < .001). There were no differences based on geographic location. Wrong items included misspelling Mohs (10%), indicating that only plastic surgeons could reconstruct (7%), and noting MMS was never cost-effective (7%). CONCLUSIONS: High-ranking websites provide basic information about MMS. Academic practice and professional society sites provide more-comprehensive information, but private practice sites and web-based medical information sources also provide additional information.

Transcriptional profiling of the dose response: a more powerful approach for characterizing drug activities.

The dose response curve is the gold standard for measuring the effect of a drug treatment, but is rarely used in genomic scale transcriptional profiling due to perceived obstacles of cost and analysis. One barrier to examining transcriptional dose responses is that existing methods for microarray data analysis can identify patterns, but provide no quantitative pharmacological information. We developed analytical methods that identify transcripts responsive to dose, calculate classical pharmacological parameters such as the EC50, and enable an in-depth analysis of coordinated dose-dependent treatment effects. The approach was applied to a transcriptional profiling study that evaluated four kinase inhibitors (imatinib, nilotinib, dasatinib and PD0325901) across a six-logarithm dose range, using 12 arrays per compound. The transcript responses proved a powerful means to characterize and compare the compounds: the distribution of EC50 values for the transcriptome was linked to specific targets, dose-dependent effects on cellular processes were identified using automated pathway analysis, and a connection was seen between EC50s in standard cellular assays and transcriptional EC50s. Our approach greatly enriches the information that can be obtained from standard transcriptional profiling technology. Moreover, these methods are automated, robust to non-optimized assays, and could be applied to other sources of quantitative data.

Effect of Topical Brimonidine on Alcohol-Induced Flushing in Asian Individuals: A Randomized Clinical Trial.

Importance: Alcohol flushing syndrome (AFS, also known as Asian glow and Asian flush) affects 20% to 47% of East Asians and causes significant psychosocial distress. There are no approved treatments for this condition. Objective: To determine whether brimonidine gel, 0.33%, decreases facial erythema in patients with AFS after consumption of alcohol. Design, Setting, and Participants: In this randomized clinical trial, 20 healthy volunteers of East Asian descent with a self-reported history of AFS were recruited between April 2018 and March 2019. Interventions: Participants were randomized to application of brimonidine gel to either the left or right half of their face. Placebo control was applied to the opposite side. After 30 minutes, participants ingested alcohol. Main Outcomes and Measures: Outcomes were specified before data collection. The difference in erythema between the treated and placebo side of each participant's face was measured 60 minutes after drug application (primary outcome) and at 90 and 120 minutes after drug application (secondary outcomes). Participants were asked to rate their likelihood of using the medication again and their likelihood of recommending the medication to a friend on a scale of 0 to 10. Results: The mean (SD) age of the 20 individuals enrolled in the study was 30.5 (8.4) years, and there were 10 women (50%). There was a significant difference in erythema at 60 minutes after drug application as measured by the difference in Clinician Erythema Assessment score (2.1; 95% CI, 1.5-2.71; P < .001) and by the difference in Subject Self-Assessment score (1.7; 95% CI, 1.1- 2.3; P < .001). This effect persisted at 90 and 120 minutes. Individuals were likely to use the medication again (7.2; 95% CI, 6.0-8.3) and would also recommend it to a friend (7.6; 95% CI, 6.5-8.6). Conclusions and Relevance: This study demonstrates that brimonidine gel is effective in reducing the facial erythema of AFS. Patients with psychosocial distress due to AFS may benefit from treatment with brimonidine. Trial Registration: ClinicalTrials.gov identifier: NCT03497442.

Comparative efficacy of nonpurpuragenic pulsed dye laser and intense pulsed light for erythematotelangiectatic rosacea.

BACKGROUND: Erythematotelangiectatic (ET) rosacea is commonly treated with a variety of laser and light-based systems. Although many have been used successfully, there are a limited number of comparative efficacy studies. OBJECTIVE: To compare nonpurpuragenic pulsed dye laser (PDL) with intense pulsed light (IPL) treatment in the ability to reduce erythema, telangiectasia, and symptoms in patients with moderate facial ET rosacea. METHODS: Twenty-nine patients were enrolled in a randomized, controlled, single-blind, split-face trial with nonpurpuragenic treatment with PDL and IPL and untreated control. Three monthly treatment sessions were performed with initial PDL settings of 10-mm spot size, 7 J/cm(2), 6-ms pulse duration and cryogen cooling, and initial IPL settings of 560-nm filter, a pulse train of 2.4 and 6.0 ms in duration separated by a 15-ms delay, and a starting fluence of 25 J/cm(2). Evaluation measures included spectrophotometric erythema scores, blinded investigator grading, and patient assessment of severity and associated symptoms. RESULTS: PDL and IPL resulted in significant reduction in cutaneous erythema, telangiectasia, and patient-reported associated symptoms. No significant difference was noted between PDL and IPL treatment. CONCLUSION: A series of nonpurpuragenic PDL and IPL treatments in ET rosacea was performed with similar efficacy and safety, and both modalities seem to be reasonable choices for the treatment of ET rosacea.

Regulatory T cells use arginase 2 to enhance their metabolic fitness in tissues.

Distinct subsets of Tregs reside in nonlymphoid tissues where they mediate unique functions. To interrogate the biology of tissue Tregs in human health and disease, we phenotypically and functionally compared healthy skin Tregs with those in peripheral blood, inflamed psoriatic skin, and metastatic melanoma. The mitochondrial enzyme, arginase 2 (ARG2), was preferentially expressed in Tregs in healthy skin, increased in Tregs in metastatic melanoma, and reduced in Tregs from psoriatic skin. ARG2 enhanced Treg suppressive capacity in vitro and conferred a selective advantage for accumulation in inflamed tissues in vivo. CRISPR-mediated deletion of this gene in primary human Tregs was sufficient to skew away from a tissue Treg transcriptional signature. Notably, the inhibition of ARG2 increased mTOR signaling, whereas the overexpression of this enzyme suppressed it. Taken together, our results suggest that Tregs express ARG2 in human tissues to both regulate inflammation and enhance their metabolic fitness.

Basal cell carcinomas arising within multiple trichoepitheliomas.

Although trichoepitheliomas (TEs) are commonly regarded as benign tumors of follicular origin, the natural history of multiple familial trichoepitheliomas (MFT) and their risk for malignancy has been unclear. We describe a 57-year-old male with numerous skin-colored firm papules and plaques present on the central face since 6 years of age. Recently, some lesions had enlarged and ulcerated. Other family members were similarly affected. Biopsies from multiple lesions showed TEs both alone and associated with basal cell carcinoma (BCC) in the same section, suggesting the secondary development of BCCs within TEs. Many prior reports of BCCs arising within TEs in patients with presumed MFT were likely misdiagnosed cases of nevoid BCC. This report is a compelling example of MFT in which BCCs evolved secondarily. Awareness of the potential for the evolution of carcinoma in patients with MFT is important in the management of these patients.

Transcriptional Programming of Normal and Inflamed Human Epidermis at Single-Cell Resolution.

Perturbations in the transcriptional programs specifying epidermal differentiation cause diverse skin pathologies ranging from impaired barrier function to inflammatory skin disease. However, the global scope and organization of this complex cellular program remain undefined. Here we report single-cell RNA sequencing profiles of 92,889 human epidermal cells from 9 normal and 3 inflamed skin samples. Transcriptomics-derived keratinocyte subpopulations reflect classic epidermal strata but also sharply compartmentalize epithelial functions such as cell-cell communication, inflammation, and WNT pathway modulation. In keratinocytes, ∼12% of assessed transcript expression varies in coordinate patterns, revealing undescribed gene expression programs governing epidermal homeostasis. We also identify molecular fingerprints of inflammatory skin states, including S100 activation in the interfollicular epidermis of normal scalp, enrichment of a CD1C+CD301A+ myeloid dendritic cell population in psoriatic epidermis, and IL1ßhiCCL3hiCD14+ monocyte-derived macrophages enriched in foreskin. This compendium of RNA profiles provides a critical step toward elucidating epidermal diseases of development, differentiation, and inflammation.

Bleeding complications in dermatologic surgery.

Although the overall incidence is low, bleeding complications in dermatologic surgery can occur and be the source of significant patient morbidity. In this article, we summarize the key aspects of preoperative assessment of patients at risk for bleeding. A review of current issues and literature regarding safe continuation of anticoagulant and antiplatelet medications in dermatologic surgery patients is also presented. In addition, principles for management of bleeding events, should they occur, are also highlighted.

Bleeding complications in dermatologic surgery.

Although the overall incidence is low, bleeding complications in dermatologic surgery can occur and be the source of significant patient morbidity. In this article, we summarize the key aspects of preoperative assessment of patients at risk for bleeding. A review of current issues and literature regarding safe continuation of anticoagulant and antiplatelet medications in dermatologic surgery patients is also presented. In addition, principles for management of bleeding events, should they occur, are also highlighted.

Infectious complications and antibiotic use in dermatologic surgery.

Infection rates in dermatologic surgery are low, ranging on average from 1 to 3%. Studies have shown that many practitioners likely overuse antibiotics, both for prevention of wound infection and in endocarditis prophylaxis. This article discusses patient and environmental risk factors in would infection. Data on wound infection prophylaxis are reviewed, and specific guidelines set forth with regards to appropriate antibiotic usage, drug selection, dosage, and timing. In addition, recommendations surrounding endocarditis and prosthetic joint infection prophylaxis are presented as they apply to dermatologic surgery.