Multispecies-targeting siRNAs for the modulation of JAK1 in the skin.

Identifying therapeutic oligonucleotides that are cross-reactive to experimental animal species can dramatically accelerate the process of preclinical development and clinical translation. Here, we identify fully chemically-modified small interfering RNAs (siRNAs) that are cross-reactive to Janus kinase 1 (JAK1) in humans and a large variety of other species. We validated the identified siRNAs in silencing JAK1 in cell lines and skin tissues of multiple species. JAK1 is one of the four members of the JAK family of tyrosine kinases that mediate the signaling transduction of many inflammatory cytokine pathways. Dysregulation of these pathways is often involved in the pathogenesis of various immune disorders, and modulation of JAK family enzymes is an effective strategy in the clinic. Thus, this work may open up unprecedented opportunities for evaluating the modulation of JAK1 in many animal models of human inflammatory skin diseases. Further chemical engineering of the optimized JAK1 siRNAs may expand the utility of these compounds for treating immune disorders in additional tissues.

Spatial characterization of interface dermatitis in cutaneous lupus reveals novel chemokine ligand-receptor pairs that drive disease.

Chemokines play critical roles in the recruitment and activation of immune cells in both homeostatic and pathologic conditions. Here, we examined chemokine ligand-receptor pairs to better understand the immunopathogenesis of cutaneous lupus erythematosus (CLE), a complex autoimmune connective tissue disorder. We used suction blister biopsies to measure cellular infiltrates with spectral flow cytometry in the interface dermatitis reaction, as well as 184 protein analytes in interstitial skin fluid using Olink targeted proteomics. Flow and Olink data concordantly demonstrated significant increases in T cells and antigen presenting cells (APCs). We also performed spatial transcriptomics and spatial proteomics of punch biopsies using digital spatial profiling (DSP) technology on CLE skin and healthy margin controls to examine discreet locations within the tissue. Spatial and Olink data confirmed elevation of interferon (IFN) and IFN-inducible CXCR3 chemokine ligands. Comparing involved versus uninvolved keratinocytes in CLE samples revealed upregulation of essential inflammatory response genes in areas near interface dermatitis, including AIM2. Our Olink data confirmed upregulation of Caspase 8, IL-18 which is the final product of AIM2 activation, and induced chemokines including CCL8 and CXCL6 in CLE lesional samples. Chemotaxis assays using PBMCs from healthy and CLE donors revealed that T cells are equally poised to respond to CXCR3 ligands, whereas CD14+CD16+ APC populations are more sensitive to CXCL6 via CXCR1 and CD14+ are more sensitive to CCL8 via CCR2. Taken together, our data map a pathway from keratinocyte injury to lymphocyte recruitment in CLE via AIM2-Casp8-IL-18-CXCL6/CXCR1 and CCL8/CCR2, and IFNG/IFNL1-CXCL9/CXCL11-CXCR3.

Rational design of a JAK1-selective siRNA inhibitor for the modulation of autoimmunity in the skin.

Inhibition of Janus kinase (JAK) family enzymes is a popular strategy for treating inflammatory and autoimmune skin diseases. In the clinic, small molecule JAK inhibitors show distinct efficacy and safety profiles, likely reflecting variable selectivity for JAK subtypes. Absolute JAK subtype selectivity has not yet been achieved. Here, we rationally design small interfering RNAs (siRNAs) that offer sequence-specific gene silencing of JAK1, narrowing the spectrum of action on JAK-dependent cytokine signaling to maintain efficacy and improve safety. Our fully chemically modified siRNA supports efficient silencing of JAK1 expression in human skin explant and modulation of JAK1-dependent inflammatory signaling. A single injection into mouse skin enables five weeks of duration of effect. In a mouse model of vitiligo, local administration of the JAK1 siRNA significantly reduces skin infiltration of autoreactive CD8+ T cells and prevents epidermal depigmentation. This work establishes a path toward siRNA treatments as a new class of therapeutic modality for inflammatory and autoimmune skin diseases.

Baseline Levels of Circulating Inflammatory Biomarkers Stratify Patients with Vitiligo Who Significantly Repigment after Treatment with Ruxolitinib Cream.

BACKGROUND: Efficacy of ruxolitinib cream, a topical Jak1/Jak2 inhibitor, was demonstrated in a phase 2 trial in patients with vitiligo. OBJECTIVE: This study aimed to characterize circulating inflammatory biomarker profiles in patients who demonstrated ≥50% improvement in facial Vitiligo Area Scoring Index scores by week 24 (group 1) and those who did not (group 2). DESIGN: This was a posthoc analysis of a multicenter, randomized, double-blind, vehicle-controlled, phase 2 study in which screening was conducted between June 7, 2017 and March 21, 2018. POPULATION: Patients aged between 18 and 75 years with vitiligo, including depigmentation affecting ≥0.5% of body surface area on the face and ≥3% of body surface area on nonfacial areas, were eligible. INTERVENTION: Patients applied 1.5% ruxolitinib cream to lesions once or twice daily for 52 weeks. MAIN OUTCOMES AND MEASURES: Patients were grouped by achievement of ≥50% improvement in facial Vitiligo Area Scoring Index at week 24. Proteomic analysis was performed on baseline serum samples. RESULTS: Mean ± standard error facial Vitiligo Area Scoring Index in group 1 (n = 30) versus group 2 (n = 27) improved by 79.9 ± 4.0% versus 1.1 ± 7.3% and 91.9 ± 1.5% versus 25.1 ± 13.4% at weeks 24 and 52, respectively. Broad proteomic analysis revealed 76 proteins (of 1,104 tested) that were differentially expressed between groups 1 and 2 at baseline (P < 0.05). Ten distinct proteins were upregulated in group 1; 64 were elevated in group 2. CONCLUSION: This analysis identified potential differences between patients who achieved ≥50% improvement in facial Vitiligo Area Scoring Index at 24 weeks and those who did not that require deeper scientific interrogation and may be important in stratifying therapeutic benefit for patients with vitiligo. TRIAL REGISTRATION: The original study was registered at ClinicalTrials.gov, NCT03099304.

Worldwide expert recommendations for the diagnosis and management of vitiligo: Position statement from the international Vitiligo Task Force-Part 2: Specific treatment recommendations.

BACKGROUND: The treatment of vitiligo can be challenging. Up-to-date agreed consensus recommendations on the use of topical and systemic therapies to facilitate the clinical management of vitiligo are currently lacking. OBJECTIVES: To develop internationally agreed-upon expert-based recommendations for the treatment of vitiligo. METHODS: In this consensus statement, a consortium of 42 international vitiligo experts and four patient representatives participated in different online and live meetings to develop a consensus management strategy for vitiligo. At least two vitiligo experts summarized the evidence for different topics included in the algorithms. A survey was then given to a core group of eight experts to resolve the remaining issues. Subsequently, the recommendations were finalized and validated based on further input from the entire group during two live meetings. RESULTS: The recommendations provided summarize the latest evidence regarding the use of topical therapies (steroids, calcineurin inhibitors and Jak-inhibitors) and systemic therapies, including steroids and other systemic immunomodulating or antioxidant agents. The different modalities of phototherapies (NB-UVB, photochemotherapy, excimer devices and home phototherapy), which are often combined with other therapies, are also summarized. Interventional approaches as well as depigmentation strategies are presented for specific indications. Finally, the status of innovative and targeted therapies under development is discussed. CONCLUSIONS: This international consensus statement culminated in expert-based clinical practice recommendations for the treatment of vitiligo. The development of new therapies is ongoing in vitiligo, and this will likely improve the future management of vitiligo, a disease that still has many unmet needs.

Worldwide expert recommendations for the diagnosis and management of vitiligo: Position statement from the International Vitiligo Task Force Part 1: towards a new management algorithm.

BACKGROUND: The treatment of vitiligo can be challenging and depends on several factors such as the subtype, disease activity, vitiligo extent, and treatment goals. Vitiligo usually requires a long-term approach. To improve the management of vitiligo worldwide, a clear and up-to-date guide based on international consensus with uniform stepwise recommendations is needed. OBJECTIVES: To reach an international consensus on the nomenclature and to develop a management algorithm for the diagnosis, assessment, and treatment of vitiligo. METHODS: In this consensus statement, a consortium of 42 international vitiligo experts and four patient representatives participated in online and live meetings to develop a consensus management strategy for vitiligo. At least two vitiligo experts summarized the evidence of topics included in the algorithms. A survey was utilized to resolve remaining issues among a core group of eight experts. Subsequently, the unanimous recommendations were finalized and validated based on further input from the entire group during two live meetings. RESULTS: The algorithms highlight the importance of shared decision-making. Dermatologists are encouraged to provide patients with detailed explanations of the prognosis and expected therapeutic outcomes based on clinical examination. The treatment goal should be discussed and clearly emphasized to patients given the different approaches for disease stabilization and repigmentation. The evaluation of disease activity remains a cornerstone in the tailor-made approach to vitiligo patients. CONCLUSIONS: These new treatment algorithms are intended to guide clinical decision-making in clinical practice. Promising novel therapies for vitiligo are on the horizon, further highlighting the need for reliable outcome measurement instruments and greater emphasis on shared decision-making.

Mental Health and Psychosocial Quality-of-Life Burden Among Patients With Vitiligo: Findings From the Global VALIANT Study.

Importance: Patients with vitiligo often have impaired quality of life (QOL) and experience substantial psychosocial burden. Objective: To explore the global association of vitiligo with QOL and mental health from the patient perspective. Design, Setting, and Participants: This qualitative study of the cross-sectional population-based Vitiligo and Life Impact Among International Communities (VALIANT) study was conducted from May 6, 2021, to June 21, 2021. Potential participants for this qualitative study were recruited from an online panel in 17 countries. Of 5859 surveyed adults (aged ≥18 years) who reported a vitiligo diagnosis, 3919 (66.9%) completed the survey, and 3541 (60.4%) were included in the analysis. Exposures: Patients were asked questions regarding their emotional well-being, including QOL and mental health. Main Outcomes and Measures: Reported analyses are descriptive and hypothesis generating. Vitiligo Impact Patient scale (VIPs) scores ranged from 0 to 60, with higher scores indicating more psychosocial burden. Results: The median age of the 3541 patients was 38 years (range, 18-95 years), and 1933 (54.6%) were male; 1602 patients (45.2%) had more than 5% affected body surface area (BSA; Self-Assessment Vitiligo Extent Score assessed), and 1445 patients (40.8%) had Fitzpatrick skin types IV to VI (ie, darker skin). The mean (SD) global short-form VIPs score was 27.3 (15.6) overall; patients from India (mean [SD], 40.2 [14.1]) reported the highest scores (ie, most burden). The QOL burden according to the scale was profound for patients with more than 5% affected BSA (mean [SD] score, 32.6 [14.2]), darker skin (mean [SD] score, 31.2 [15.6]), and lesions on the face (mean [SD] score, 30.0 [14.9]) or hands (mean [SD], 29.2 [15.2]). At least 40% of patients globally reported that vitiligo frequently affected aspects of their daily lives, including choosing clothes to wear (1956 of 3541 [55.2%]). Most patients (2103 of 3541 [59.4%]) reported concealing their vitiligo frequently. More than half of patients (2078 of 3541 [58.7%]) reported diagnosed mental health conditions, including anxiety (1019 of 3541 [28.8%]) and depression (866 of 3541 [24.5%]). The Patient Health Questionnaire-9 depression screener showed that 55.0% of patients (1948 of 3541) had moderate to severe depressive symptoms; the highest rates were in India (271 of 303 [89.4%]) and among patients with more than 5% affected BSA (1154 of 1602 [72.0%]) and darker skin (987 of 1445 [68.3%]). Conclusions and Relevance: This qualitative study found that, globally, patients with vitiligo reported being substantially affected in their emotional well-being, daily lives, and psychosocial health; the burden was typically greatest among patients with more than 5% affected BSA, darker skin types, and lesions on the face or hands. Survey findings suggest that patients reported having altered their behavior, expressed clear discontent, and have symptoms consistent with depression, which may be underdiagnosed.

Lesional CD8+ T-Cell Number Predicts Surgical Outcomes of Melanocyte-Keratinocyte Transplantation Surgery for Vitiligo.

The melanocyte-keratinocyte transplantation procedure (MKTP) treats stable and recalcitrant vitiligo. Despite careful selection of candidates based on clinical stability, the success of the procedure is unpredictable. The aim of our study was to define the immunological profile of stable vitiligo lesions undergoing MKTP and correlate them with clinical outcomes. We included 20 MKTP candidates with vitiligo and a patient with piebaldism as a control. Prior to MKTP, T-cell subsets and chemokines in the recipient skin were measured by flow cytometry and ELISA. During MKTP, melanocytes in the donor skin were quantified by flow cytometry. After MKTP, patients were followed for 12 months and repigmentation was assessed clinically and by ImageJ analysis of clinical photographs. Baseline immunologic biomarkers, duration of clinical stability, and transplanted melanocyte number were correlated to postsurgical repigmentation scores. CD8+ T cells were elevated in 43% of the clinically stable vitiligo lesions. CD8+ T-cell number negatively correlated with postsurgical repigmentation scores (r = -0.635, P = 0.002). Duration of clinical stability, skin chemokines, and transplanted melanocyte number did not influence postsurgical repigmentation. This study demonstrates that CD8+ T-cell number correlates negatively with success of postsurgical repigmentation and can be a biomarker to identify ideal surgical candidates.

Exploring the natural and treatment history of vitiligo: perceptions of patients and healthcare professionals from the global VALIANT study.

BACKGROUND: Vitiligo is a chronic autoimmune disease affecting melanocytes, resulting in skin depigmentation. Patients with vitiligo often have reduced quality of life and comorbid autoimmune conditions and have reported a lack of available treatments for their vitiligo. OBJECTIVES: The Vitiligo and Life Impact Among International Communities (VALIANT) study is the first global survey to explore the natural history and management of vitiligo from the perspectives of patients and healthcare professionals (HCPs). METHODS: The survey recruited adults (≥ 18 years) diagnosed with vitiligo and HCPs treating patients with vitiligo via an online panel in 17 countries. Patients were queried regarding clinical characteristics and vitiligo treatment. HCPs were queried regarding diagnosis and management of patients with vitiligo. RESULTS: Included in the analysis were 3541 patients and 1203 HCPs. Nearly half (45.2%) of the patients had > 5% affected body surface area; 57.1% reported family history. Patients obtained formal diagnosis after a mean (SD) of 2.4 (4.1) years; 44.9% reported previous misdiagnosis. Many patients (56.7%) reported being told that vitiligo could not be treated; 53.9% of HCPs believed patients who never treated their vitiligo had been told that vitiligo could not be treated. One-quarter of HCPs (26.3%) did not believe that an effective therapy for vitiligo exists; 44.6% of patients reported giving up on finding an effective therapy. Top treatment goals for patients and HCPs, respectively, were reduction or cessation of spread (24.7% and 18.5%) and repigmentation (22.5% and 37.2%). Patient perception of effective care was similar for treatment by dermatologists (66.9%) and primary care HCPs (67.0%). CONCLUSIONS: Patients with vitiligo and HCPs reported similar treatment goals and expressed frustration with the lack of effective therapies. Patients reported high rates of initial misdiagnosis; many ceased seeking healthcare because they perceived that vitiligo could not be treated. The findings highlight the need for earlier diagnosis and improved disease management for vitiligo.

Adolescent extra-truncal progressive macular hypomelanosis.

Two adolescent females presented to outpatient clinic with isolated, non-scaly, asymptomatic hypopigmented macules and patches on the arm(s). Both cases had Wood's lamp exams notable for extralesional punctiform coral-red perifollicular fluorescence on the back and faint intralesional enhancement. In one case, biopsy was performed and deemed consistent with progressive macular hypomelanosis. The patient had complete response to antimicrobial therapy and sun exposure.

Activation of the NLRP1 inflammasome in human keratinocytes by the dsDNA mimetic poly(dA:dT).

The accrual of cytosolic DNA leads to transcription of type I IFNs, proteolytic maturation of the IL-1 family of cytokines, and pyroptotic cell death. Caspase-1 cleaves pro-IL1ß to generate mature bioactive cytokine and gasdermin D which facilitates IL-1 release and pyroptotic cell death. Absent in melanoma-2 (AIM2) is a sensor of dsDNA leading to caspase-1 activation, although in human monocytes, cGAS-STING acting upstream of NLRP3 mediates the dsDNA-activated inflammasome response. In healthy human keratinocytes, AIM2 is not expressed yet caspase-1 is activated by the synthetic dsDNA mimetic poly(dA:dT). Here, we show that this response is not mediated by either AIM2 or the cGAS-STING-NLRP3 pathway and is instead dependent on NLRP1. Poly(dA:dT) is unique in its ability to activate NLRP1, as conventional linear dsDNAs fail to elicit NLRP1 activation. DsRNA was recently shown to activate NLRP1 and prior work has shown that poly(dA:dT) is transcribed into an RNA intermediate that stimulates the RNA sensor RIG-I. However, poly(dA:dT)-dependent RNA intermediates are insufficient to activate NLRP1. Instead, poly(dA:dT) results in oxidative nucleic acid damage and cellular stress, events which activate MAP3 kinases including ZAKα that converge on p38 to activate NLRP1. Collectively, this work defines a new activator of NLRP1, broadening our understanding of sensors that recognize poly(dA:dT) and advances the understanding of the immunostimulatory potential of this potent adjuvant.

CXCL9 Links Skin Inflammation and Fibrosis through CXCR3-Dependent Upregulation of Col1a1 in Fibroblasts.

Morphea is characterized by initial inflammation followed by fibrosis of the skin and soft tissue. Despite its substantial morbidity, the pathogenesis of morphea is poorly studied. Previous work showed that CXCR3 ligands CXCL9 and CXCL10 are highly upregulated in the sera and lesional skin of patients with morphea. We found that an early inflammatory subcutaneous bleomycin mouse model of dermal fibrosis mirrors the clinical, histological, and immune dysregulation observed in human morphea. We used this model to examine the role of the CXCR3 chemokine axis in the pathogenesis of cutaneous fibrosis. Using the REX3 (Reporting the Expression of CXCR3 ligands) mice, we characterized which cells produce CXCR3 ligands over time. We found that fibroblasts contribute the bulk of CXCL9-RFP and CXCL10-BFP by percentage, whereas macrophages produce high amounts on a per-cell basis. To determine whether these chemokines are mechanistically involved in pathogenesis, we treated Cxcl9-, Cxcl10-, or Cxcr3-deficient mice with bleomycin and found that fibrosis is dependent on CXCL9 and CXCR3. Addition of recombinant CXCL9 but not CXCL10 to cultured mouse fibroblasts induced Col1a1 mRNA expression, indicating that the chemokine itself contributes to fibrosis. Taken together, our studies provide evidence that CXCL9 and its receptor CXCR3 are functionally required for inflammatory fibrosis.

Systemic therapies in vitiligo: a review.

Vitiligo is characterized by the development of depigmented macules and patches. Autoimmunity has been established as a factor in disease pathogenesis, leading to utilization of immunosuppressive agents. Topical immunosuppressants are commonly used; however, this treatment modality is often cumbersome and inefficient, as many patients have active disease with extensive body surface area involvement. Prompt and aggressive treatment of vitiligo is important, as this may prevent progression and improve quality of life. To meet these challenges and improve patient outcomes, interest in systemic therapies has grown. Currently, oral therapies are rarely prescribed, likely due to concerns with systemic side effects and unclear efficacy. This article provides a brief overview on the use of systemic agents in treating vitiligo in order to provide additional therapeutic options to clinicians.