From mice to men: An assessment of preclinical model systems for the study of vitiligo.

Vitiligo is an autoimmune skin disease of multiple etiology, for which there is no complete cure. This chronic depigmentation is characterized by epidermal melanocyte loss, and causes disfigurement and significant psychosocial distress. Mouse models have been extensively employed to further our understanding of complex disease mechanisms in vitiligo, as well as to provide a preclinical platform for clinical interventional research on potential treatment strategies in humans. The current mouse models can be categorized into three groups: spontaneous mouse models, induced mouse models, and transgenic mice. Despite their limitations, these models allow us to understand the pathology processes of vitiligo at molecule, cell, tissue, organ, and system levels, and have been used to test prospective drugs. In this review, we comprehensively evaluate existing murine systems of vitiligo and elucidate their respective characteristics, aiming to offer a panorama for researchers to select the appropriate mouse models for their study.

Vitiligo-like Lesions as a Predictor of Response to Immunotherapy in Non-Small Cell Lung Cancer: Comprehensive Review and Case Series from a University Center.

The reference to vitiligo-like lesions (VLLs) induced by immune checkpoint inhibitors (ICIs) as a valuable predictive marker of treatment success of immunotherapy with ICIs in melanoma has been mentioned in the literature. Its role in non-small cell lung cancer (NSCLC)-treated patients remains a poorly recognized phenomenon with uncertain significance regarding its predictive value. A retrospective, observational, single-center report was performed, with descriptive analysis of clinicopathological and treatment characteristics of patients with stage IV NSCLC who developed ICI-induced VLL between January 2018 and December 2022, contextualized in a comprehensive review of the literature and reported cases regarding this phenomenon. During the first 5 years' experience of ICI use in stage IV NSCLC treatment, three cases of ICI-induced VLLs were diagnosed. In line with the previous reports, two of the three presented cases exhibited treatment response and favorable prognosis. The recognition and understanding of the pathophysiological processes underlying ICI-induced VLLs may represent a promising opportunity to identify a predictive marker of tumor response to ICIs, with impact in treatment selection and patient management. It also may contribute to the recognition of new patterns of molecular expression that could lead to improvements in therapeutic development.

Cigarette smoking is an independent risk factor for developing vitiligo on the hands.

BACKGROUND: Vitiligo presents with varying clinical features based on the type and location. Treatment tends to be more effective on the face, neck, trunk, and mid-extremities, while the lips and distal extremities may be more resistant. Vitiligo in frequently exposed areas such as the face, arms, legs, and hands is typically associated with a lower Dermatology Life Quality Index. OBJECTIVES: We aimed to identify the characteristics and potential causes of vitiligo in challenging-to-treat regions, with particular focus on the hands. METHODS: We analyzed the clinical data of 337 patients with generalized vitiligo who visited our hospital between 2016 and 2022. For this study, we focused on patients with non-segmental vitiligo (NSV) specifically on their hands. Of the 337 patients, 248 had NSV and 89 had segmental vitiligo; 119 (47%) of those with NSV had vitiligo on their hands. Logistic regression models were applied to identify factors the factors linked to hand vitiligo, such as age, sex, duration of the condition, and smoking and alcohol history. RESULTS AND CONCLUSIONS: We developed a model to predict the risk of hand vitiligo using several factors. Among the factors analyzed, only smoking history was significantly associated with an increased risk (odds ratio: 3.13). In addition, we used clinical photography to evaluate color-graded frequency heat maps comprising 528 pixels. Vitiligo in nonsmokers widely distributed over the hand, predominantly the fingertips and joints, whereas vitiligo in smokers tended to be distributed mostly at the fingertips.

Risk of Subsequent Vitiligo in Transplant Recipients With Comorbid Graft-vs-Host Disease.

Importance: Vitiligo is a multifactorial, depigmenting skin disorder characterized by selective loss of melanocytes. Large-scale studies are lacking to determine the risk of vitiligo in transplant recipients with graft-vs-host disease (GVHD). Objective: To investigate the incidence rates and risk of vitiligo in patients who had received solid organ transplant (SOT) or hematopoietic stem cell transplant (HSCT) overall and by HSCT graft type and concomitant GVHD. Design, Setting, and Participants: This population-based cohort study included data from the National Health Insurance Service database of Korea for patients aged 20 years or older who had received a transplant (SOT or HSCT) between January 2010 and December 2017, with follow-up until December 2019. A cohort of age- and sex-matched (1:5) control individuals who did not receive a transplant was included for comparison. Data were analyzed from July 2021 to December 2021. Exposure: Transplant (SOT or HSCT) and GVHD. Main Outcomes and Measures: The main outcome was risk of vitiligo, assessed using multivariable Cox proportional hazards regression analyses adjusting for potential confounding factors. Results: The study included 23 829 patients who had undergone SOT or HSCT (62.78% male; mean [SD] age, 49.58 [11.59] years) and 119 145 age- and sex-matched controls. Patients who had undergone transplant had a significantly higher risk of vitiligo compared with controls (adjusted hazard ratio [AHR], 1.73; 95% CI, 1.35-2.22). Risk of vitiligo was also slightly higher in kidney transplant recipients and liver transplant recipients compared with the controls but was highest in HSCT recipients (AHR, 12.69; 95% CI, 5.11-31.50). Patients who had received allogeneic grafts (AHR, 14.43; 95% CI, 5.61-37.15), those who had received autologous grafts (AHR, 5.71; 95% CI, 1.20-3.18), those with comorbid GVHD (AHR, 24.09; 95% CI, 9.16-63.35), and those without GVHD (AHR, 8.21; 95% CI, 3.08-21.87) had a higher risk of vitiligo compared with controls. Conclusion and Relevance: In this study, risk of vitiligo was significantly higher in transplant recipients, especially in HSCT recipients and those with allogeneic grafts or comorbid GVHD. These findings provide new insights into the association between the risk of vitiligo and transplant and GVHD. Clinicians should be aware of these risks, implementing a multidisciplinary approach for monitoring.

A case of vitiligo after COVID-19 vaccination: a possible role of thymic dysfunction. / 一例由2019å† ç— æ¯’ç— (COVID-19)ç–«è‹—æŽ¥ç§å¼•å‘çš„ç™½ç™œé£Žç— ä¾‹åŠå ¶èƒ¸è ºåŠŸèƒ½éšœç¢çš„ä½œç”¨æœºåˆ¶åˆ†æž.

During the coronavirus disease 2019 (COVID-19) pandemic, vaccines help control the spread of infection. To date, 47 vaccines have been approved, with another 227 candidates in various stages of development. In the short period of time since the beginning of their use, evidence has begun to emerge of complications following vaccination in the form of the development or exacerbation of a number of pathological conditions (Block et al., 2022; Haseeb et al., 2022). For example, a population-based study in France identified 1612 cases of myocarditis and 1613 cases of pericarditis requiring hospital treatment within five months of vaccination (le Vu et al., 2022).

Using a Topical Formulation of Vitamin D for the Treatment of Vitiligo: A Systematic Review.

Vitamin D is one significant prohormone substance in human organ systems. It is a steroidal hormone produced in the skin upon exposure to UVB rays. This paper presents a systematic review of the utilization of topical vitamin D, specifically cholecalciferol, calcipotriol, and tacalcitol, in the treatment of vitiligo. It considers the role of vitamin D in stimulating the synthesis of melanin and melanogenesis, which can help with the process of repigmentation. The inclusion of calcipotriol or tacalcitol in Narrowband Ultraviolet Phototherapy (NB-UVB) has shown the potential to enhance therapeutic outcomes for vitiligo. However, their effectiveness in combination with Psoralens Long Wave Ultraviolet Radiation (PUVA) and Monochromatic Excimer Light (MEL) treatment for vitiligo is limited. In contrast, combining topical corticosteroids with vitamin D analogues has demonstrated superior efficacy in treating vitiligo compared to using vitamin D analogues alone, while also providing the added benefit of reducing corticosteroid-related adverse effects. In addition, treating stable vitiligo with topical cholecalciferol and microneedling has shown success. Future studies are needed to ascertain an efficient method of administering vitamin D topically as an anti-vitiligo agent.

Etiopathogenesis and Emerging Methods for Treatment of Vitiligo.

Vitiligo is an acquired chronic depigmenting disorder of skin. It is mostly asymptomatic and characterized by amelanotic macules and patches that affects 0.5% to 2% of the world's population. The etiology of vitiligo has not been clearly elucidated and multiple theories have been proposed regarding the causes of the disorder. Among the most prevalent theories, the genetic predisposition, oxidative stress theory, promotion of cellular stress and pathologic influence of lymphocytes T have been highlighted. As a result of increases in in-depth knowledge concerning the pathogenetic processes in vitiligo, we review the most recent information concerning its etiopathogenesis and treatment methods including topical and oral Janus kinase inhibitors, prostaglandins and their analogues, namely afamelanotide, Wnt/ß-catenin-signaling agonists and cell-based therapies. Topical ruxolitinib has been registered for vitiligo treatment, whereas other agents as oral ritlecitinib, afamelanotide and latanoprost have been studied in ongoing clinical trials. New highly effective therapeutic strategies may be developed thanks to molecular and genetic studies.

Demographic and clinical feature disparity between progress and non-progress patients with vitiligo after COVID-19 vaccination: A cross-sectional study.

There have been several case reports regarding newly developed vitiligo following the coronavirus disease 19 (COVID-19) vaccination. However, the relationship between COVID-19 vaccine and vitiligo progression remains unclear. To explore the relationship between COVID-19 vaccine and vitiligo progression and its potential influencing factors, A cross-sectional study was conducted on 90 patients with vitiligo who received inactivated COVID-19 vaccination. Detailed information covering demographic characteristics (age and sex), vitiligo clinical features (disease subtypes, duration, stage and comorbidities) and disease activity was collected through an electronic questionnaire. Ninety patients with vitiligo included 44.4% males, with an average age of 38.1 years (standard deviation, SD = 15.0). Patients were divided into progress group (29, 32.2%) and normal group (61, 67.8%) based on whether they experienced vitiligo progression after inactivated COVID-19 vaccination. 41.3% of patients in the progress group experienced vitiligo progression within 1 week after vaccination, and disease progression mainly occurred after the first dose inoculation (20, 69.0%). Logistic regression revealed that patients aged <45 years (odds ratio (OR) was 0.87, 95% confidence interval (CI): 0.34-2.22) and male patients (OR = 0.84, 95% CI: 0.34-2.05) had lower risk for vitiligo progression, while patients with segmental vitiligo (SV) subtype (OR = 1.68, 95% CI: 0.53-5.33), with <5 years disease duration (OR = 1.32, 95% CI: 0.51-3.47) had higher risk for vitiligo progression after COVID-19 vaccination, but without statistical significance. Over 30% patients experienced vitiligo progression after inactivated COVID-19 vaccination, and female patients, elder age, shorter disease duration and SV subtype are potential risk factors for vitiligo progression.

Vitiligo, from Pathogenesis to Therapeutic Advances: State of the Art.

Vitiligo is an acquired hypopigmentation of the skin due to a progressive selective loss of melanocytes; it has a prevalence of 1-2% and appears as rounded, well-demarcated white macules. The etiopathology of the disease has not been well defined, but multiple factors contribute to melanocyte loss: metabolic abnormalities, oxidative stress, inflammation, and autoimmunity. Therefore, a convergence theory was proposed that combines all existing theories into a comprehensive one in which several mechanisms contribute to the reduction of melanocyte viability. In addition, increasingly in-depth knowledge about the disease's pathogenetic processes has enabled the development of increasingly targeted therapeutic strategies with high efficacy and fewer side effects. The aim of this paper is, by conducting a narrative review of the literature, to analyze the pathogenesis of vitiligo and the most recent treatments available for this condition.

Melanocyte Adhesion and Apoptosis in Vitiligo: Linking Puzzle Blocks.

Vitiligo is the utmost common depigmenting condition consequential from melanocyte loss from the basal layer of the epidermis. Vitiligo disease mostly affects dark-skinned races and makes them more sensitive to UV radiation. It is also linked with some autoimmune diseases and various psychosocial difficulties. Melanocyte loss leads to depigmentation in vitiligo, is a major concern over decades, and even affects an individual's day-to-day life severely. All the theories, including autoimmune, autocytotoxic, and neural, collectively decipher either prime impact on the melanogenesis inhibition or deficient adhesion inspired melanocytes disappearance. Previously it has been described that melanocyte loss in vitiligo patients is caused by defective adhesion. Melanocyte death by apoptosis mainly occurs due to melanocyte detachment or migration from the basal layer and further followed by transepidermal migration. Various cell surface molecules, i.e., cell adhesion molecules (CAMs) in affiliation with neighbouring cells and extracellular matrix (ECM), encompass a typical cell adhesion process. All these ECM molecules along with transcription factors, help in the survival and maintenance of pigmentary cells/melanocytes. Therefore, in this issue, we have tried to compile the literature available on melanocyte detachment/apoptosis in ECM due to the alteration in adhesion molecules and matrix metalloproteinases (MMPs) driven by known/unknown transcription factors.

Vitiligo-like manifestations of graft-versus-host disease in a pediatric population.

Vitiligo-like changes are an uncommon cutaneous manifestation of graft-versus-host disease (GVHD). We report three cases and review the literature of pediatric patients with vitiligo-like changes associated with GVHD. Improved characterization of this phenomenon may lend insight into the biologic pathways that underlie both vitiligo and GVHD.

Investigation of optimal energy or density of a fractional CO2 laser system in the treatment of stable non-segmental vitiligo.

BACKGROUND: Fractional carbon dioxide (CO2) laser has been considered to be an add-on to conventional treatments of vitiligo. OBJECTIVE: This study aimed to evaluate the optimal energy and density of the fractional CO2 laser system in stable non-segmental vitiligo (NSV) patients. METHOD: 48 patients were treated with fractional CO2 laser and sequential phototherapies of narrowband ultraviolet B (NB-UVB), after the CO2 laser treatment, a compound betamethasone solution was topically applied. For the fractional CO2 laser, coverages of 8% and 12.6% were set as low density (Ld) and high density (Hd), and energies of 60 mJ and 80 mJ were set as low energy (Le) and high energy (He), respectively. The patients were randomly assigned to Group A (HeHd), Group B (HeLd) or Group C (LeLd). RESULTS: Either after 3 or 6 months of enrollment, the efficacy of Group C was better than Group B (p < 0.05). No difference was seen between Group A and Group B or Group A and Group C (p > 0.05). More patients complained higher pain score in Group A as compared with Group C (p < 0.05). CONCLUSION: The optimal parameters of the fractional CO2 laser were energy at 60 mJ and density at 8%.

Efficacy of a topical formulation containing MIA (Melanoma Inhibitory Activity) - Inhibitory peptides in a case of recalcitrant vitiligo in combination with UV exposure.

INTRODUCTION: Vitiligo is an acquired chronic pigmentation disorder of the skin. Even if the role of the immune system seems to be well established, new pathogenetic hypothesis are rising in these years. It has been recently suggested by the development of an animal model that a protein called Melanoma Inhibitory Activity (MIA) is involved in the pathogenesis of vitiligo. This protein interacts with the adhesion molecules expressed on the melanocytes causing its detachment from extracellular matrix proteins and creating the depigmented macules. A topical preparation based on oligopeptides able to inhibit the actions of the MIA protein has been introduced to the market, claiming activity on vitiligo. PATIENT CONCERNS AND DIAGNOSIS: A patient affected by non-segmental vitiligo for 10 years, recalcitrant to any treatment (such as steroids, immunomodulators, kellin, UVB-NB and UVA) came to our observation. INTERVENTIONS: We used this topical preparation containing the MIA inhibitors peptides in selected areas (face and sides of the trunk) leaving untreated other areas as control (legs and arms). The patient was required to be sun exposed or to have some UVA sessions during the treatment to stimulate the melanocytes replications. OUTCOMES: After 9 months of treatments, he recovered from 50% to 80% of repigmentation only in the treated areas, without any side effects locally or systemically. CONCLUSION: Even if other studies are required to better determine the efficacy of this approach, this first observation about the use of the MIA-inhibitors peptides for the treatment of non-segmental vitiligo indicates that this topical preparation containing the MIA inhibitors peptides could be a very promising option for the cure of this disease.

Different vitiligo characteristics as predictors of increased risk of metabolic syndrome and insulin resistance: A case-control study.

BACKGROUND: Autoimmune and metabolic disturbances have been reported in association with vitiligo, highlighting possible systemic associations that should be considered. AIMS: To assess the possible association of metabolic syndrome (MetS) as well as insulin resistance (IR) with vitiligo in different age groups. METHODS: This case-control study included 142 patients with vitiligo aging ≥ 6 years and 142 age- and sex-matched controls. Participants were assessed for MetS using the International Diabetes Federation (IDF) criteria in addition to IR via homeostasis model assessment of IR (HOMA-IR). The study was registered at Clinical Trials.gov, Identifier: NCT03622320, on August 9, 2018. RESULTS: As per the IDF criteria, patients with vitiligo showed significantly more frequent association with high fasting plasma glucose levels, high blood pressure readings, central obesity, dyslipidemia, and MetS than controls (p = 0.020, p = 0.034, p = 0.014, p < 0.001, and p = 0.002, respectively). Moreover, patients with vitiligo have significantly higher levels of fasting insulin and HOMA-IR (p ≤ 0.001). Results obtained from patients with vitiligo and controls with coexistent MetS/IR demonstrated vitiligo as a risk factor for both MetS and IR. Univariate and multivariate logistic regression highlighted that older age was the significant independent predictor for MetS and IR. CONCLUSION: Patients with vitiligo showed a significantly higher incidence of MetS than controls. Vitiligo per se can be considered a risk factor for MetS and IR. Therefore, regular follow-up and early metabolic derangement diagnoses are mandatory.