A comparative study of suction blister epidermal grafting and automated blister epidermal micrograft in stable vitiligo.

The automated blister epidermal micrograft (ABEM) is a newly introduced surgical transplantation for refractory vitiligo. Comparative analysis of other surgical methods is lacking. We conducted a retrospective study to compare the efficacy, safety, and experience of ABEM with conventional suction blister epidermal graft (SBEG). A total of 118 anatomically based vitiligo lesions from 75 patients were included. The primary outcome was the degree of repigmentation; the patient and operator experience were evaluated. SBEG had a significantly greater incidence of repigmentation (p < 0.001), as measured by the Physician Global Assessment, as well as improvements in the Vitiligo Area Scoring Index, particularly on the face/neck area (p < 0.001). ABEM, on the contrary, had reduced donor harvest time, a better patient operative experience, and more significant Dermatology Life Quality Index improvements. In a subgroup of 38 lesions from ten patients who received both SBEG and ABEM concomitantly, there was no difference in the degree of repigmentation in the same recipient area. Overall, the degree of repigmentation for SBEG is higher than ABEM, especially in the mobilized region, and the cost is less expensive. On the contrary, ABEM requires less procedure learning curve and can supply a greater transplanting zone with shorter donor site recovery. Understanding the benefits and drawbacks of two blister grafting procedures is essential for optimal surgical outcomes for vitiligo grafting.

Repigmentation by combined narrow­band ultraviolet B/adipose­derived stem cell transplantation in the mouse model: Role of Nrf2/HO­1­mediated Ca2+ homeostasis.

Vitiligo is a depigmentation disease commonly seen in clinical practice, mainly involving loss of functional epidermal pigment cells and hair follicle melanocytes. Narrow­band ultraviolet B (NB­UVB) has emerged as the first choice of treatment for vitiligo, but long­term exposure may have serious consequences. Recently, it was reported that adipose­derived stem cells (ADSCs) improve melanocyte growth and the efficacy of melanocyte transplantation. The present study aimed to examine the efficacy of NB­UVB/ADSC­transplantation combined therapy on a mouse vitiligo model and explore the underlying mechanisms by focusing on endoplasmic reticulum stress and cellular calcium (Ca2+) homeostasis. Vitiligo mice models were established by applying 40% monobenzone (MBZ) cream twice daily and treated with NB­UVB/ADSC combination therapy. Some treated mice were also given ML385, a nuclear factor erythroid 2 like 2 (Nr2) inhibitor. Histopathological changes were evaluated using a depigmentation evaluation score and observed with hematoxylin and eosin staining on skin tissues. ELISA was used to measure diagnostic markers in plasma. Flow cytometric assay was performed to quantify CD3+, CD4+ and CD8+ levels. Expression levels of associated proteins were detected with western blot and immunofluorescence. Treatment of mice with MBZ­induced depigmentation patches on the skin was accompanied with loss of redox balance and disruption of cellular Ca2+ homeostasis. Oxidative stress and Ca2+ unbalancing were improved after the mice were treated by NB­UVB/ADSCs transplantation combination therapy. ML385, strongly negated the protective effect of NB­UVB/ADSC transplantation combination therapy, indicating the critical role of Nr2 signaling. The findings improved the understanding of the pathogenesis of vitiligo and will guide future development of therapeutic strategies against it.

Vitiligo induced by immune checkpoint inhibitors in melanoma patients: an expert opinion.

Introduction: Treatment with immune checkpoint inhibitors in melanoma patients can cause immune-related adverse effects, such as vitiligo. In vitiligo, specific autoimmunity against melanocytes results in depigmentation of the skin. Melanoma-associated vitiligo occurring in melanoma patients treated with immune checkpoint inhibitors can be seen as a good prognostic sign as higher survival rates in melanoma-associated vitiligo cases have been reported.Areas covered: This review gives an insight into the pathophysiology, clinical presentation, and management of melanoma-associated vitiligo caused by immune checkpoint inhibitors.Expert opinion: Development of melanoma-associated vitiligo induced by immune checkpoint inhibitors could be a good clinical marker for response and overall survival. Induction of vitiligo in these patients could also potentially lead to better response and survival rates. Further research should focus on several aspects of melanoma-associated vitiligo, such as better screening and registration, more understanding of pathophysiology of the type of immune response and the predictive value of melanoma-associated in patients treated with immune checkpoint inhibitors.

Integrating neuronal involvement into the immune and genetic paradigm of vitiligo.

In this review we show how the neuronal theory is relevant to the convergence theory for the mechanism causing vitiligo, especially the segmental type. Neuropeptides and neurotransmitters, such as neuropeptide Y and dopamine, can be central to the pathological mechanisms of melanocyte destruction. They link into a bidirectional network connecting cutaneous nerves, the neuroendocrine axis and the immune system, and through their local influence on cutaneous inflammation, to the antigen-specific regulatory T cells and the chemokine ligand type 9/chemokine receptor type 1 axis, which is thought to be the final pathway for melanocyte destruction.

PINK1 in normal human melanocytes: first identification and its effects on H2 O2 -induced oxidative damage.

BACKGROUND: Oxidative stress plays an important role in initiating the destruction of melanocytes, which could be one possible mechanism of vitiligo. PINK1 is an outer membrane protein of mitochondria, which protects many cells from oxidative stress through regulating mitochondrial function. However, the role of PINK1 and its effects on oxidative damage in melanocytes have not been elucidated. AIM: To investigate the expression and effects of PINK1 on oxidative stress in human melanocytes. METHODS: Quantitative reverse transcription-PCR and western blot analysis were used to analyse the expression of PINK1 in PIG1 melanocyte and gene downregulation models. Levels of cell viability, cell apoptosis and intracellular reactive oxygen species (ROS), mitochondrial morphology, mitochondrial membrane potential (MMP) and mitochondrial permeability transition pore (MPTP) opening were measured in PIG1 models transfected with PINK1 small interfering RNA with or without hydrogen peroxide (H2 O2 ). RESULTS: We first observed the expression of PINK1 in human PIG1 melanocytes and found that downregulation of PINK1 made melanocytes more sensitive to oxidative stress induced by H2 O2 , with more cell apoptosis and increased intracellular ROS. Meanwhile, downregulation of PINK1 caused morphological changes in mitochondria, decreased the MMP and increased MPTP opening. CONCLUSIONS: Our study found PINK1 plays an essential role in protecting human melanocytes from oxidative stress.

Targeting the PD-1/PD-L1 Axis in Human Vitiligo.

Autoreactive CD8+ T cells play a pivotal role in melanocyte destruction in autoimmune vitiligo. Immunotherapy for melanoma often leads to autoimmune side-effects, among which vitiligo-like depigmentation, indicating that targeting immune checkpoints can break peripheral tolerance against self-antigens in the skin. Therapeutically enhancing immune checkpoint signaling by immune cells or skin cells, making self-reactive T cells anergic, seems a promising therapeutic option for vitiligo. Here, we review the current knowledge on the PD-1/PD-L1 pathway in vitiligo as new therapeutic target for vitiligo therapy.

Identification of key genes and pathways involved in vitiligo development based on integrated analysis.

Vitiligo is a chronic skin condition lack of melanocytes. However, researches on the aetiology and pathogenesis of vitiligo are still under debate. This study aimed to explore the key genes and pathways associated with occurrence and development of vitiligo.Weighted gene coexpression network analysis (WGCNA) was applied to reanalyze the gene expression dataset GSE65127 systematically. Functional enrichments of these modules were carried out at gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), gene set variation analysis (GSVA), and gene set enrichment analysis (GSEA). Then, a map of regulatory network was delineated according to pivot analysis and drug prediction. In addition, hub genes and crucial pathways were validated by an independent dataset GSE75819. The expressions of hub genes in modules were also tested by quantitative real-time polymerase chain reaction (qRT-PCR).Eight coexpressed modules were identified by WGCNA based on 5794 differentially expressed genes of vitiligo. Three modules were found to be significantly correlated with Lesional, Peri-Lesional, and Non-Lesional, respectively. The persistent maladjusted genes included 269 upregulated genes and 82 downregulated genes. The enrichments showed module genes were implicated in immune response, p53 signaling pathway, etc. According to GSEA and GSVA, dysregulated pathways were activated incessantly from Non-Lesional to Peri-Lesional and then to Lesional, 4 of which were verified by an independent dataset GSE75819. Finally, 42 transcription factors and 228 drugs were spotted. Focusing on the persistent maladjusted genes, a map of regulatory network was delineated. Hub genes (CACTIN, DCTN1, GPR143, HADH, MRPL47, NKTR, NUF2) and transcription factors (ITGAV, SYK, PDPK1) were validated by an independent dataset GSE75819. In addition, hub genes (CACTIN, DCTN1, GPR143, MRPL47, NKTR) were also confirmed by qRT-PCR.The present study, at least, might provide an integrated and in-depth insight for exploring the underlying mechanism of vitiligo and predicting potential diagnostic biomarkers and therapeutic targets.

Vitiligo management: combination of surgical treatment and phototherapy under reflectance confocal microscopy monitoring.

OBJECTIVE: Vitiligo is a chronic acquired pigmentary skin disorder characterized by well-defined asymptomatic white macule as a result of loss of functional melanocytes in the epidermis. The psychological burden experienced by patients is of great interest and consequently research of the best medical approach is constantly developing. This review focuses on surgical approach and the combination of surgery and phototherapy. In addition, reflectance confocal microscopy (RCM) could be useful to discriminate between stable or active vitiligo and to evaluate efficacy of therapy. MATERIALS AND METHODS: We searched PubMed with the following keywords: (vitiligo[Title/Abstract]) AND therapy[Title/Abstract]) AND surgery[Title/Abstract]) AND phototherapy[Title/Abstract]) AND reflectance confocal microscopy[Title/Abstract]). RESULTS: To date, surgery is an effective therapeutic approach in stable vitiligo. Phototherapy, which is the most effective medical option, can improve the results obtained with surgery if performed in combination. Preliminary data show that RCM help physician in evaluating stability of vitiligo and is also useful to monitor clinical response. CONCLUSIONS: Vitiligo is a psychosocially debilitating disease requiring a multidisciplinary approach. Even if a standard management could not be stated, combination of surgery and phototherapy in stable vitiligo could lead to great improvement than monotherapy. RCM is a modern tool which should be used in order to perform surgery and phototherapy properly and to subsequently evaluate efficacy on a microscopic level.

H2 O2 -induced oxidative stress disrupts mitochondrial functions and impairs migratory potential of human epidermal melanocytes.

Reactive oxygen species (ROS) have already been demonstrated to impede the migratory ability in non-melanocytic cell lines by depleting mitochondrial ATP production. Therefore, understanding the mitochondrial metabolic response to migration in the presence of ROS should be a key to understanding repigmentation in vitiligo. This study aimed to investigate the energy mechanism associated with the ROS-mediated attenuation of melanocyte migration. After melanocytes were pretreated with H2 O2 , their ATP production, migratory ability, ultrastructural changes and Mitochondrial Permeability Potential were analysed. The results showed that, in parallel with the decreased ATP production, the migratory ability of melanocytes was significantly inhibited by oxidative stress. Supplementation with exogenous ATP reversed the suppressed ATP-dependent migration of melanocytes. Melanocytes were then stressed with H2 O2 and Agilent Whole Human Genome microarray analysis identified 763 up-regulated mRNAs and 1117 down-regulated mRNAs. Among them, 11 of the encoded proteins were involved in mitochondrial ATP production and their expression levels were verified. The decreased expression of NADH dehydrogenase 2(ND2) , cytochrome c oxidase 1(COX1) and cytochrome c oxidase 3(COX3) was shown to be involved in the depletion of mitochondrial ATP production, which was coupled with the impaired migratory potential. These results indicate that the migration of melanocytes relies heavily on an inexhaustible supply of ATP from mitochondria.

The enigma and challenges of vitiligo pathophysiology and treatment.

Vitiligo is the most common acquired pigmentary disorder, which afflicts 0.5%-1% of the world population, and is characterized by depigmented skin patches resulting from melanocyte loss. Vitiligo has a complex etiology and varies in its manifestations, progression, and response to treatment. It presents as an autoimmune disease, evidenced by circulating melanocyte-specific antibodies, and association with other autoimmune diseases. However, autoimmunity may be secondary to the high oxidative stress in vitiligo skin and to intrinsic defects in melanocytes and their microenvironment, which contribute to aberrant stress response, neo-antigenicity, and susceptibility of melanocytes to immune attack and apoptosis. There is also a genetic predisposition to vitiligo, which sensitizes melanocytes to environmental agents, such as phenolic compounds. Currently, there are different treatment modalities for re-pigmenting vitiligo skin. However, when repigmentation is achieved, the major challenge is maintaining the pigmentation, which is lost in 40% of cases. In this review, we present an overview of the clinical aspects of vitiligo, its pathophysiology, the intrinsic defects in melanocytes and their microenvironment, and treatment strategies. Based on lessons from the biology of human melanocytes, we present our perspective of how repigmentation of vitiligo skin can be achieved and sustained.

Current insight into the roles of microRNA in vitiligo.

Vitiligo is a common chronic depigmented skin disease characterized by melanocyte loss or dysfunction in the lesion. The pathogenesis of vitiligo has not been fully clarified. Most studies have suggested that the occurrence and progression of vitiligo are due to multiple factors and gene interactions in which noncoding RNAs contribute to an individual's susceptibility to vitiligo. Noncoding RNAs, including microRNAs (miRNAs), are a hot topic in posttranscriptional regulatory mechanism research. miRNAs are noncoding RNAs with a length of approximately 22 nucleotides and play a negative regulatory role by binding to the 3'-UTR or 5'-UTR of the target mRNA to inhibit translation or initiate mRNA degradation. Previous studies have screened the differential expression profiles of miRNAs in the skin lesions, melanocytes, peripheral blood mononuclear cells (PBMCs) and sera of patients and mouse models with vitiligo. Moreover, several studies have focused on miRNA-25, miRNA-155 and other miRNAs involved in melanin metabolism, oxidative stress, and melanocyte proliferation and apoptosis. These miRNAs and regulatory processes further illuminate the pathogenesis of vitiligo and provide hope for the application of small molecules in the treatment of vitiligo. In this review, we summarize miRNA expression profiles in different tissues of vitiligo patients and the mechanisms by which key miRNAs mediate vitiligo development.

Lesional skin in vitiligo exhibits delayed in vivo reepithelialization compared to the nonlesional skin.

Vitiligo, a common skin disorder, is characterized by the loss of functional melanocytes resulting in the depigmentation of skin. Previous studies have demonstrated molecular and architectural alterations in the epidermal keratinocytes upon loss of melanocytes. The physiological implications of these "altered" keratinocytes are yet not known. We investigated the wound healing efficiency of lesional vs nonlesional skin in 12 subjects with stable nonsegmental vitiligo using histological and ultrastructural evaluation of partial-thickness wounds. The wounds were examined 12 days postinjury, coinciding with the reepithelialization phase of healing marked primarily by keratinocyte migration and proliferation. This study demonstrated a significant difference in the reepithelialization potential between the lesional and nonlesional skin. While all 12 nonlesional wounds demonstrated considerable neoepidermis formation on the 12th day post wound, only four of the corresponding lesional samples showed comparable reepithelialization; the rest remaining in the inflammatory phase. Ultrastructural studies using transmission electron microscopy as well as immunohistochemical staining revealed a reduced number of desmosomes, shorter keratin tonofilaments and an increase in myofibroblast population in the dermis of lesional reepithelialized tissue compared to the nonlesional reepithelialized samples. This study implicates gross functional perturbations in the lesional skin during physiological wound healing in vitiligo, suggesting that the breakdown of keratinocyte-melanocyte network results in delayed wound repair kinetics in the lesional skin when compared to patient-matched nonlesional skin.

Association of Clinical Markers With Disease Progression in Patients With Vitiligo From China.

Importance: It is necessary to determine whether established clinical markers of vitiligo are associated with disease progression, severity, and patient prognosis. Objective: To evaluate the utility of trichrome sign, confetti-like depigmentation, and Koebner phenomenon in assessing disease progression, severity, and prognosis in patients with vitiligo. Design, Setting, and Participants: In this prospective cohort study, 425 patients with vitiligo were recruited from the outpatient department of Huashan Hospital, Fudan University in Shanghai, China, from September 1, 2016, to May 13, 2019. Main Outcomes and Measures: Disease progression, severity, and prognosis during a 12-month period. The active stage of vitiligo was defined as Vitiligo European Task Force spreading score of at least 1 or more lesions appearing as hypomelanotic with poorly defined borders using a Wood light. Progression was assessed using the Vitiligo Area Scoring Index (VASI) and serum CXCL10 level measurement. Results: Of the 458 enrolled patients, 425 (235 female [55.3%]; mean [SD] age, 30.9 [10.2] years) completed the 12-month follow-up. Of the 425 patients (224 with no clinical marker and 201 with at least 1 clinical marker) included in this analysis, the proportion in the active stage of the disease was significantly higher in the cohort with at least 1 clinical marker compared with the cohort without any clinical marker at the first visit (196 of 201 [97.5%] vs 159 of 224 [71.0%]; P < .001) and at 3-month follow up (91 of 201 [45.3%] vs 52 of 224 [23.2%]; P < .001). The proportion of patients with rapid disease progression was also higher in the group with at least 1 clinical marker at 1-month follow-up (142 of 201 [70.6%] vs 60 of 224 [26.8%]; P < .001) and 3-month follow-up (63 of 201 [31.3%] vs 9 of 224 [4.0%]; P < .001). The improvement in VASI score (SD) was significantly smaller among patients with at least 1 clinical marker compared with those without any clinical marker at 6 months (mean [SD], 0.14 [0.12] vs 0.23 [0.21]; P = .02), at 9 months (mean [SD], 0.29 [0.19] vs 0.44 [0.25]; P = .03), and at 12 months (mean [SD], 0.47 [0.21] vs 0.63 [0.23]; P = .03). Conclusions and Relevance: The presence of a clinical marker in patients with vitiligo may be associated with worse prognosis and rapid disease progression. Patients with multiple clinical markers may require more intensive treatment.

The relationship between stress and vitiligo: Evaluating perceived stress and electronic medical record data.

Vitiligo is a T-cell mediated skin disorder characterized by progressive loss of skin color. In individuals genetically predisposed to the disease, various triggers contribute to the initiation of vitiligo. Precipitating factors can stress the skin, leading to T-cell activation and recruitment. Though hereditary factors are implicated in the pathogenesis of vitiligo, it is unknown whether precipitating, stressful events play a role in vitiligo. To understand this, we utilized a validated perceived stress scale (PSS) to measure this parameter in vitiligo patients compared to persons without vitiligo. Additionally, we probed a clinical database, using a knowledge linking software called ROCKET, to gauge stress-related conditions in the vitiligo patient population. From a pool of patients in an existing database, a hundred individuals with vitiligo and twenty-five age- and sex-matched comparison group of individuals without vitiligo completed an online survey to quantify their levels of perceived stress. In parallel, patients described specifics of their disease condition, including the affected body sites, the extent, duration and activity of their vitiligo. Perceived stress was significantly higher among vitiligo individuals compared to those without vitiligo. ROCKET analyses suggested signs of metabolic-related disease (i.e., 'stress') preceding vitiligo development. No correlation was found between perceived stress and the stage or the extent of disease, suggesting that elevated stress may not be a consequence of pigment loss alone. The data provide further support for stress as a precipitating factor in vitiligo development.