Research Publications

Question 1

A comparative study of an advanced skin imaging system in diagnosing facial pigmentary and inflammatory conditions

Accepted Answer

Visual assessment, while the primary method for pigmentation and erythema evaluation in clinical practice, is subjective, time-consuming, and may lead to variability in observations among clinicians. Objective and quantitative techniques are required for a precise evaluation of the disease's severity and the treatment's efficacy. This research examines the precision and utility of a newly developed skin imaging system in assessing pigmentation and erythema. Sixty participants were recruited, and their facial images were analyzed with the new OBSERV 520 x skin imaging system, compared to DERMACATCH for regional analysis and VISIA for full-face examination. The degree of skin pigmentation was clinically graded using the MASI scores evaluated by dermatologists. The data revealed positive correlations between the novel skin imaging system and the two conventional instruments in quantifying pigmentation and erythema, whether in regional or full-face analysis. Furthermore, the new skin imaging system positively correlated with the clinical MASI scores (r = 0.4314, P < 0.01). In contrast, our study found no significant correlation between the traditional system and clinical assessment, indicating a more substantial capacity for hyperpigmentation assessment in the new system. Our study validates the innovative skin imaging system's accuracy in evaluating pigmentation and erythema, demonstrating its feasibility for quantitative evaluation in both clinical and research purposes.

Question 2

From zero to one: Recent advances in the pathogenesis, diagnosis, and treatment of vitiligo.

Accepted Answer

Abstract： Vitiligo is the most common acquired pigmentary disorder and can have profound negative psychosocial impacts on patients. The disease course of vitiligo is often unpredictable, and diagnosis and treatment of vitiligo remain a challenging dermatological task. In this review, we touch on new advances in understanding vitiligo pathogenesis; discuss emerging biomarkers that may aid physicians in assessing vitiligo disease activity and severity, and summarize prospective targeted therapies in treating vitiligo. A brief outline dedicated to the impact of the coronavirus disease 2019 pandemic on vitiligo patients is also provided. We hope that readers may acquire a more comprehensive understanding of vitiligo and gain insights into new diagnostic tools and therapeutic options for vitiligo. Read the Paper

Question 3

Skin Interstitial Fluid and Plasma Multiplex Cytokine Analysis Reveals IFN-γ Signatures and Granzyme B as Useful Biomarker for Activity, Severity and Prognosis Assessment in Vitiligo

Accepted Answer

Abstract： Background: The course of vitiligo is unpredictable, with periods of disease flare-ups and prolonged recovery periods. It is essential to establish a biomarker profile as a substitute marker for disease activity to predict disease activity, severity, and prognosis prediction. The use of localized skin interstitial fluid as biomarkers has recently gained interest, but extensive studies of the association between skin interstitial fluid, plasma, and the disease course is lacking. This study aims to evaluate the cytokine expression profiles in the skin and plasma and the utility of the biomarker panel in assessing disease activity, severity, and prognosis in patients with vitiligo. Methods: In this prospective cohort study, 86 patients and 34 healthy controls were recruited from the outpatient department of a tertiary medical center from March 2019 to September 2021. All patients were of Asian ethnicity. Two independent investigators evaluated disease activity and severity with longitudinal follow-ups for treatment response for a-12 month period. Ultrasensitive multiplex cytokine panel and single-molecule counting technology immunoassays were used to study the cytokine expression in skin interstitial fluid and plasma. Results: IFN-γ and its’ signature cytokines, including CXCL9, CXCL10, and GzmB, are most highly expressed in the vitiligo patients’ lesion skin interstitial fluid and plasma compared to healthy control. By way of comparison, no significant changes in IL-1β, IL-13, IL-15, IL-17A, IL-18 were observed. Receiver operating characteristic analysis revealed that IFN-γ is the most sensitive and specific marker in predicting disease activity, followed by CXCL10 and GzmB. CXCL-9 was sensitive and specific in diagnosing vitiligo disease severity. The decrease in IFN-γ expression level is positively correlated with the treatment response. Conclusion: IFN-γ, CXCL9, CXCL10, and GzmB are highly expressed in vitiligo patients’ lesion skin and plasma and may serve as biomarkers for the clinical activity, severity, and prognosis prediction in vitiligo patients. Among all, IFN-γ exerts the highest predictive value in disease activity and treatment response, supporting the critical role of IFN-γ in the pathogenesis of vitiligo. Read the Paper

Question 4

Targeting the elevated IFN - γ in vitiligo patients by human anti - IFN - γ monoclonal antibody hampers direct cytotoxicity in melanocyte

Accepted Answer

Abstract： Vitiligo is an autoimmune disease that progressively destroys melanocytes in theskin, resulting in patchy disfiguringdepigmentation. The direct pathologicaleffect of IFN-γ,CXCL10 to the melanocytesin vitiligo has been reported, but there arecontradictory results to which cytokineexerts the critical cytotoxic effect onmelanocytes.We obtained the interstitial fluid analytefrom lesion and non-lesion skin of vitiligopatients and healthy control and sent forhigh sensitivity multiplex cytokine panel. Wefurther performed functional study toidentify the direct toxicity effect of the highlyexpressed cytokines.We found a significant elevation of IFN-γ,CXCL9, CXCL10, CXCL11 in the vitiligoskin. Ex vivo melanocyte studies supportthe directrole of IFN-γper se in melanocytecell loss, increased oxidative stress andmelanogenesis disruption. Interestingly, wefound that IFN-γregulated cell deaththrough oxidative stress-related ferroptosiscell death, which may initiate autoimmunityin vitiligo. In contrast to blocking selectedcell death pathway, our in vitro studysupports the rescue effect of human anti-IFN-γmonoclonal antibody 2A6Q to IFN-γinduced cell death, oxidative stress, andloss of function in melanocytes byinterrupting IFN-γsignaling, which may bea potential therapeutic option for vitiligo. Read the Paper

Question 5

Pathogenic autoantibodies to IFN-γ act through the impedance of receptor assembly and Fc-mediated response

Accepted Answer

Abstract： Anti-interferon (IFN)–γ autoantibodies (AIGAs) are a pathogenic factor in late-onset immunodeficiency with disseminated mycobacterial and other opportunistic infections. AIGAs block IFN-γ function, but their effects on IFN-γ signaling are unknown. Using a single-cell capture method, we isolated 19 IFN-γ–reactive monoclonal antibodies (mAbs) from patients with AIGAs. All displayed high-affinity (KD < 10−9 M) binding to IFN-γ, but only eight neutralized IFN-γ–STAT1 signaling and HLA-DR expression. Signal blockade and binding affinity were correlated and attributed to somatic hypermutations. Cross-competition assays identified three nonoverlapping binding sites (I–III) for AIGAs on IFN-γ. We found that site I mAb neutralized IFN-γ by blocking its binding to IFN-γR1. Site II and III mAbs bound the receptor-bound IFN-γ on the cell surface, abolishing IFN-γR1–IFN-γR2 heterodimerization and preventing downstream signaling. Site III mAbs mediated antibody-dependent cellular cytotoxicity, probably through antibody–IFN-γ complexes on cells. Pathogenic AIGAs underlie mycobacterial infections by the dual blockade of IFN-γ signaling and by eliminating IFN-γ–responsive cells. Read the Paper

Question 6

Feasibility of Oral Tranexamic acid (TA) for Vitiligo Patients with Melasma

Accepted Answer

Abstract： Melasma and vitiligo are both common pigmentary disorders, and the treatment is challenging. Oral tranexamic acid (TA) is effective for refractory melasma; however, the feasibility of TA in vitiligo patients with melasma was not studied. To evaluate the treatment outcomes and adverse effects of oral TA in vitiligo patients with melasma. We conducted a retrospective analysis of vitiligo patients who received oral TA for melasma in a tertiary dermatologic center from January 2017 to August 2020. We enrolled 32 patients with concomitant vitiligo and melasma on the face. The mean duration of the improvement of melasma that patients reported is around 1.64 months of treatment. The first sign of repigmentation of the vitiligo lesions occurred at 1 month of treatment. 84.38% of the patients achieved a mild to good degree of improvement of melasma (0%–75% improvement), whereas 81.25% of the patients achieved a moderate to excellent degree of improvement of vitiligo (25%–100% improvement) via physician global assessments. No significant adverse event was noted. No patients experience vitiligo disease deterioration during TA treatment. Oral TA may be a feasible option for melasma in vitiligo patients. Read the Paper

Question 7

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

Accepted Answer

Abstract： 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. Read the Paper

Question 8

Efficacy and safety of automated epidermal micrograft in patients with stable segmental and nonsegmental vitiligo

Accepted Answer

Abstract： Vitiligo is a common, psychologically devastating pigmentary disorder. Surgical graftings are used to treat stable vitiligo when medical treatment fails. An automated epidermal micrograft harvesting (AEMH) system was first designated to treat wounds, and very few studies investigated the application of AEMH in vitiligo. In this study, we investigated the efficacy and safety of the AEMH system in patients with stable segmental and nonsegmental vitiligo. The rate of repigmentation and adverse events was recorded bimonthly for at least 12 months. We analyzed the efficacy based on patient characteristics, vitiligo subtypes, and different anatomical locations. A total of 56 depigmented lesions from 34 patients were included. 95.50% of the automated epidermal micrografts were successfully grafted at the recipient sites. There was a significant improvement in Vitiligo Area Scoring Index (VASI) and Dermatologic Life Quality Index (DLQI) in patients treated with AEMH (p < 0.001). The rate of repigmentation by VASI score improves from 96.25 ± 8.59 to 48.30 ± 28.16 after the treatment (p < 0.001). Treatment outcomes were comparable between the patients of segmental and stable nonsegmental vitiligo. The face and neck region achieved a better outcome, followed by the trunk (chest, abdomen, back, and axilla), limbs, and the worse outcome was found in the acral region (p < 0.014). Conclusively, AEMH is an effective treatment procedure with limited adverse events in patients with stable vitiligo. This harvesting method may be a feasible option for vitiligo surgical treatment. Read the Paper

Question 9

Feasibility of High-Cellular-Resolution Full-Field, Artificial-Intelligence-Assisted, Real-Time Optical Coherence Tomography in the Evaluation of Vitiligo: A Prospective Longitudinal Follow-Up Study.

Accepted Answer

Abstract： Vitiligo, a psychologically distressing pigmentary disorder characterized by white depigmented patches due to melanocyte loss, necessitates non-invasive tools for early detection and treatment response monitoring. High-cellular-resolution full-field optical coherence tomography (CRFF-OCT) is emerging in pigmentary disorder assessment, but its applicability in vitiligo repigmentation after tissue grafting remains unexplored. To investigate the feasibility of CRFF-OCT for evaluating vitiligo lesions following tissue grafting, our investigation involved ten vitiligo patients who underwent suction blister epidermal grafting and laser ablation at a tertiary center between 2021 and 2022. Over a six-month period, clinical features, dermoscopy, and photography data were recorded. Utilizing CRFF-OCT along with artificial intelligence (AI) applications, repigmentation features were captured and analyzed. The CRFF-OCT analysis revealed a distinct dark band in vitiligo lesion skin, indicating melanin loss. Grafted areas exhibited melanocytes with dendrites around the epidermal-dermal junction and hair follicles. CRFF-OCT demonstrated its efficacy in the early detection of melanocyte recovery and accurate melanin quantification. This study introduces CRFF-OCT as a real-time, non-invasive, and in vivo evaluation tool for assessing vitiligo repigmentation, offering valuable insights into pigmentary disorders and treatment responses. Read the Paper

Question 10

Association of multiple sclerosis with vitiligo: a systematic review and meta- analysis

Accepted Answer

Abstract： Polyautoimmunity implicates that some autoimmune diseases share common etiopathogenesis. Some studies have reported an association between multiple sclerosis (MS) and vitiligo; meanwhile, other studies have failed to confirm this association. We performed a systemic review and meta-analysis to examine the association of MS with vitiligo. We searched the MEDLINE and Embase databases on March 8, 2020 for relevant case–control, cross-sectional, and cohort studies. The Newcastle–Ottawa Scale was used to evaluate the risk of bias of the included studies. Where applicable, we performed a meta-analysis to calculate the pooled odds ratio (OR) for case–control/cross-sectional studies and risk ratio for cohort studies with 95% confidence interval (CI). Our search identified 285 citations after removing duplicates. Six case–control studies with 12,930 study subjects met our inclusion criteria. Our meta-analysis found no significant association of MS with prevalent vitiligo (pooled OR 1.33; 95% CI 0.80‒2.22). Analysis of the pooled data failed to display any increase of prevalent vitiligo in MS patients compared with controls. Ethnic and genetic factors may play an important role for sporadically observed associations between MS and vitiligo. Future studies of this association should therefore consider stratification by ethnic or genetic factors. Read the Paper