Objective:To investigate the disease control rate and its influencing factors in patients with progressive non-segmental vitiligo after combined treatment with systemic compound betamethasone injection (CBI) .Methods:A retrospective analysis was conducted on the patients with progressive non-segmental vitiligo, who visited and were treated with CBI in the Department of Dermatology, Hangzhou Third People′s Hospital from October 2022 to April 2023. The disease control rate was analyzed after 3-month treatment. Effects of clinical factors such as disease onset characteristics, duration, disease condition and treatment methods on the disease control rate were analyzed. Chi-square test was used for comparisons of enumeration data between groups, and logistic regression analysis was conducted to analyze factors influencing the efficacy.Results:A total of 145 progressive non-segmental vitiligo patients treated with CBI were collected, including 56 males and 89 females, aged 14 - 67 (35.43 ± 11.54) years. Among the 18 patients having received an intramuscular injection of CBI, 10 (55.6%) obtained stable condition; among the 105 having received 2 injections of CBI, 60 (59.0%) obtained stable condition; among the 22 having received 3 or 4 injections of CBI, 12 (54.5%) obtained stable condition. The overall disease control rate after treatment was 57.9% (84 cases). The disease control rate was significantly higher in the patients with the lesional area < 1% body surface area (BSA) (42/47, 89.4%) than in those with the lesional area ≥ 1% BSA (42/98, 42.9%; P < 0.001), significantly higher in the patients with disease duration ≤ 2 years (32/41, 78.0%) than in those with disease duration > 2 years (52/104, 50.0%; P < 0.05), and significantly higher in the patients treated with CBI combined with phototherapy (33/44, 75.0%) than in those treated with CBI alone (21/44, 47.7%; χ2 = 6.90, P = 0.009), but significantly lower in the patients with special clinical markers (Koebner phenomenon, trichrome vitiligo, confetti-like depigmentation, inflammatory vitiligo, etc., 4/21, 19.9%) than in those without special clinical markers (80/124, 64.5%, P < 0.001). Among the patients with the lesional area ≥ 1% BSA and receiving 2 injections of CBI, the disease control rate was also significantly higher in the patients treated with CBI combined with phototherapy (21/36, 58.3%) than in those treated with CBI alone (12/37, 32.4%; χ2 = 4.94, P = 0.026). There was no significant difference in the disease control rate after the treatment between the patients with first-onset and reccurrent vitiligo, between those with and without predisposing factors, between those with and without family history, among those with different vitiligo disease activity scores, among those with different number of injections, as well as among those with different treatment intervals (all P > 0.05). Multivariate logistic regression analysis showed that the lesional area ( OR = 8.11, 95% CI: 2.74 - 24.04), disease duration ( OR = 0.26, 95% CI: 0.07 - 0.99), having or not having special clinical markers ( OR = 6.37, 95% CI: 1.72 - 23.57), and whether or not receiving combined phototherapy ( OR = 0.34, 95% CI: 0.15 - 0.77) were factors influencing the efficacy (all P < 0.05) . Conclusion:CBI may be suitable for the treatment of mild to moderate progressive vitiligo, especially for patients with lesional area < 1% BSA, while not for those with lesional area > 5% BSA, and combining phototherapy may improve the control rate of progressive vitiligo.

Objective:To investigate the effect of human tumor suppressor folliculin (FLCN) on the expression of melanocyte chemokines (MC) mediated by immune factors in vitiligo.Methods:The MC of vitiligo patients that received autologous melanocyte transplantation in the Department of Dermatology, Hangzhou Third People′s Hospital from January to April 2019 were collected. The blister fluid of the white spot and the normal part was taken. Western blot was used to analyze the expression difference of MC and FLCN protein in normal, vitiligo patients and that induced by immune factors; FLCN shRNA lentivirus was constructed by shRNA and transfected into normal MC (FLCN shRNA MC) to interfere with the expression of silenced FLCN gene. The effect of immune factors on chemokines in FLCN shRNA MC was detected by ELISA.Results:The results of Western blot showed that FLCN protein was highly expressed in melanocytes of vitiligo patients, immune factors stimulated FLCN protein expression in normal melanocytes significantly increased ( t=1.27; P<0.001), chemokine CXCL10 and CCL20 also significantly increased ( t=104.53 and 60.21, respectively; P<0.001). The expression of FLCN in FLCN shRNA MC was significantly decreased ( F=1.95, P<0.001); and the high expression of CXCL10 and CCL20 induced by immune factors was significantly inhibited ( F=93.676 and 74.096, all P<0.001). Conclusions:Immune factors can stimulate the expression of CXCL10 and CCL20, which are closely related to vitiligo, while FLCN is a key protein involved in immune factors inducing melanocyte chemokine expression.

Objective:To investigate the role of folliculin in apoptosis of and chemokine secretion by melanocytes mediated by interferon-γ (IFN-γ) .Methods:Normal primary melanocytes were isolated from circumcised foreskin tissues from a healthy male child, and primary vitiliginous melanocytes were isolated from normally pigmented suction-blistered epidermis from patients with vitiligo after suction blister epidermal grafting. Western blot analysis was performed to determine the folliculin protein expression in normal primary melanocytes, primary vitiliginous melanocytes and a human primary melanocyte line PIG1. PIG1 cells stimulated with 10 ng/ml IFN-γ for 48 hours served as induction group, and untreated PIG1 cells served as control group. Real-time quantitative RCR (qRT-PCR) was performed to determine the mRNA expression of folliculin, autophagy-related microtubule-associated protein 1 light chain 3 (LC3) -Ⅱ and Beclin genes, and Western blot analysis to determine the protein expression of folliculin, Beclin1 and LC3Ⅱ/Ⅰ, as well as phosphorylation levels of adenosine monophosphate-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR) in the above cells. Furthermore, the melanocytes stimulated with 10 ng/ml IFN-γ for 48 hours were divided into several groups: negative control group infected with an empty lentiviral vector, folliculin inhibition group infected with a folliculin-inhibiting lentivirus, autophagy enhancement group infected with a folliculin-inhibiting lentivirus followed by 2-hour treatment with a mTOR inhibitor, autophagy inhibition group infected with a folliculin-inhibiting lentivirus followed by 2-hour treatment with an AMPK inhibitor. Then, flow cytometry was conducted to detect apoptosis of PIG1 cells, and enzyme-linked immunosorbent assay to measure the concentration of chemokines CXCL10 and CCL20 in the culture supernatant of PIG1 cells in the above groups. Measurement data were compared among multiple groups by using one-way analysis of variance, and multiple comparisons were carried out by using least significant difference- t test. Results:The relative protein expression level of folliculin significantly differed among the normal primary melanocytes (0.850 ± 0.120) , primary vitiliginous melanocytes (1.507 ± 0.170) and PIG1 cells (0.697 ± 0.130; F = 50.09, P < 0.001) , and was significantly higher in the primary vitiliginous melanocytes than in the normal primary melanocytes and PIG1 cells ( t = 4.06, 5.89, respectively, both P < 0.01) . Compared with the control group, the induction group showed significantly increased relative mRNA and protein expression levels of folliculin (both P < 0.01) , but significantly decreased relative mRNA and protein expression levels of LC3Ⅱ and Beclin (all P < 0.01) ; moreover, the induction group showed significantly decreased LC3Ⅱ/Ⅰ levels (0.72 ± 0.02) and AMPK phosphorylation levels (0.714 ± 0.023) in the PIG1 cells compared with the control group (1.13 ± 0.02, 1.176 ± 0.002, t = 7.34, 6.67, respectively, both P < 0.01) , but significantly increased mTOR phosphorylation levels (1.051 ± 0.023) compared with the control Group (0.451 ± 0.016, t = 3.81, P = 0.009) . There were significant differences in the PIG1 cell apoptosis rate and concentrations of CXCL10 and CCL20 among the control group, induction group and other treatment groups (all P < 0.001) ; specifically, the PIG1 cell apoptosis rate and concentrations of CXCL10 and CCL20 were significantly higher in the induction group than in the control group, lower in the folliculin inhibition group than in the negative control group, lower in the autophagy enhancement group than in the folliculin inhibition group, and higher in the autophagy inhibition group than in the folliculin inhibition group (all P < 0.05) . Conclusions:Folliculin is highly expressed in vitiliginous melanocytes. Folliculin expression and downstream signaling pathways are regulated by IFN-γ, and folliculin may participate in IFN-γ-mediated melanocyte apoptosis and chemokine secretion via regulating autophagy.

Objective:To investigate the efficacy of systemic glucocorticoid treatment and its related factors in progressive vitiligo patients with vitiligo disease activity (VIDA) scores ≥ 2 points.Methods:A total of 272 progressive vitiligo patients with VIDA scores ≥ 2 points and skin lesion area < 1% of body surface area, who received no systemic glucocorticoid treatment, were collected from Department of Dermatology, the Third People′s Hospital of Hangzhou from June 2018 to June 2019. The area and type of skin lesions, VIDA scores, predisposing factors and special clinical markers (trichrome vitiligo, confetti-like depigmentation, Koebner phenomenon and inflammatory vitiligo) were analyzed. These patients were randomly divided into 3 groups by a random number table: topical glucocorticoid group (62 cases) , oral prednisone + topical glucocorticoid group (76 cases) and compound betamethasone injection + topical glucocorticoid group (134 cases) , and the latter two groups were also called as the systemic and topical glucocorticoid group. The patients in the topical glucocorticoid group were treated with halometasone cream or 0.05% clobetasol propionate cream once a day; during the oral prednisone treatment, the dose was adjusted once every 7 days, and gradually reduced from 30 mg/d to 20, 15, 10 and 5 mg/d, and the treatment lasted 35 days; during the treatment with compound betamethasone injection, intramuscular injection was performed once every 20 days at a dose of 1 ml for 2 sessions. The stable disease rate (defined as the proportion of patients experiencing no progression during the study among the analyzed patients) was calculated in these groups after 3 months of treatment, and changes in vitiligo types were evaluated after 1 year of follow-up. Statistical analysis was carried out by using Kruskal-Wallis H test, χ2 test and Fisher′s exact test. Results:After 3-month treatment, there was a significant difference in the expansion rate of skin lesion area among the 3 groups ( H = 12.468, P < 0.001) , and the expansion rate of skin lesion area was significantly lower in the oral prednisone + topical glucocorticoid group and compound betamethasone injection + topical glucocorticoid group than in the topical glucocorticoid group ( P < 0.001, = 0.005, respectively, α = 0.016 7) ; among the patients with slowly progressive vitiligo (VIDA scores = 2 or 3 points) , the stable disease rate was significantly higher in the systemic and topical glucocorticoid group than in the topical glucocorticoid group ( χ2 = 23.973, 11.877, respectively, both P < 0.001) ; the stable disease rate also significantly differed among the patients with different VIDA scores (VIDA scores = 2, 3 or 4 points) in the systemic and topical glucocorticoid group ( χ2 = 17.122, P < 0.001) . After 3-month treatment, the patients with predisposing factors or special clinical markers showed significantly decreased stable disease rate (47.3% [35/74], 41.2% [47/114], respectively) compared with those without predisposing factors or special clinical markers (70.6% [96/136], 87.5% [84/96]; χ2 = 11.098, 47.548, respectively, both P < 0.001) . After 1 year of follow-up, the proportion of patients with localized vitiligo converted into non-localized vitiligo was significantly higher in the topical glucocorticoid group (41.9%, 26/62) than in the systemic and topical glucocorticoid group (21.9%, 46/210; χ2 = 10.328, P = 0.006) , and higher in the group with predisposing factors or special clinical markers than in that without predisposing factors or special clinical markers respectively (both P < 0.01) . Conclusions:Early systemic glucocorticoid treatment should be performed in the progressive vitiligo patients with high VIDA scores, predisposing factors and special clinical markers.

Objective:To identify and differentiate cell subsets in the epidermis and dermis of vitiligo skin lesions using single-cell RNA sequencing technology, and to study the relationship between them.Methods:Skin samples were collected from 2 healthy people without immune or systemic diseases and 2 patients with stable non-segmental vitiligo in Department of Dermatology in the Third People′s Hospital of Hangzhou in September 2019. Single-cell transcriptome sequencing was performed on 11 000 cells in all the skin samples by using 10 × Genomics single-cell RNA-Seq technology. Cell subsets were analyzed, screened and counted by using Seurat software.Results:Cluster analysis of gene expression in the 2 normal skin tissues revealed several cell subsets, including keratinocytes, fibroblasts, nerve cells and melanocytes, endothelial cells, tissue stem cells, and immune cells mainly consisting of dendritic cells and T cells. In the 2 vitiligo lesions, abnormal differentiation and quantity were observed in fibroblasts and 4 keratinocyte subpopulations. The proportion of fibroblasts was significantly lower in vitiligo lesions than in normal skin tissues (0 vs. 0.4%) , while the proportions of keratinocyte subpopulations 5, 6, 10 and 12 (8.03%, 7.36%, 3.52%, 0.91%, respectively) in vitiligo lesions were significantly higher than those in the normal skin tissues (4.47%, 3.53%, 2.69%, 0.28%, respectively, all P < 0.01) . Moreover, the above keratinocyte subpopulations were at the end of cell differentiation, and expressed very significant and specific marker genes, which were mainly closely related to cell-cell interactions and cell homeostasis. GO and KEGG analysis showed that keratinocyte subpopulations 5 and 6 were mainly related to intercellular connection, cell adhesion and cytoskeleton function, while the keratinocyte subpopulation 10 was closely related to cell homeostasis. Conclusion:The single-cell sequencing technology was firstly used to study the transcriptional expression profile of vitiligo lesions in China, and preliminary analysis revealed 4 groups of keratinocytes with different quantity and functions, suggesting that abnormal differentiation and dysfunction of keratinocyte subpopulations may affect the occurrence and development of vitiligo.

Objective:To preliminarily evaluate the effect of Fam114A1 on the biological function of melanocytes.Methods:A375 human melanoma cells was used to construct stably Fam114A1-overexpressing or -inhibited cell line by lentiviral transfection, namely overexpression group and expression inhibition group respectively, and A375 cells transfected with an empty lentivirus served as control group. Real-time fluorescence-based quantitative PCR was performed to evaluate effect of Fam114A1 on the mRNA expression of melanin synthesis-related genes tyrosinase (TYR) , tyrosinase-related protein 1 (TYRP1) , premelanosome protein (PMEL) , microphthalmia-associated transcription factor (MITF) and dopachrome isomerase (DCT) , Western blot analysis was conducted to determine the protein expression of TYR and MITF, methyl thiazol tetrazolium (MTT) assay, Transwell migration and adhesion assays were conducted to assess the effect of Fam114A1 on cellular proliferative activity, migratory and adhesive ability of A375 cells respectively. Statistical analysis was carried out by using one-way analysis of variance and Dunnett- t test. Results:Fluorescence microscopy showed that lentivirus-based transfection efficiency was about 90% in the 3 groups. Compared with the control group (0.850 ± 0.120) , the protein expression of Fam114A1 significantly increased in the overexpression group (1.507 ± 0.170, t = 5.888, P = 0.001) , but significantly decreased in the expression inhibition group (0.397 ± 0.120, t = 4.065, P = 0.007) , suggesting that the stably Fam114A1-overexpressing or -inhibited A375 cell line was successfully constructed. Real-time fluorescence-based quantitative PCR and Western blot analysis showed that the mRNA and protein expression of TYR and MITF were significantly lower in the expression inhibition group than in the control group (all P < 0.01) , but did not differ between the overexpression group and control group (all P > 0.05) . Compared with the control group, the expression inhibition group showed significantly increased cellular proliferative activity and adhesive ability ( P = 0.009, 0.001, respectively) , but significantly decreased migratory ability ( P = 0.005) , while the overexpression group only showed significantly increased migratory ability ( P = 0.021) . Conclusions:Fam114A1 can affect the proliferative activity, migratory and adhesive abilities of A375 cells, and the expression of melanin synthesis-related proteins TYR and MITF in A375 cells. Fam114A1 may be a functional protein involved in regulating the biological activity of melanocytes.

The pathogenesis of vitiligo is complicated, and the loss of melanocytes plays a central role. Besides deficiency in melanocytes, it is considered that dysfunction of epidermal and dermal cell populations as well as their interaction with melanocytes also play important roles in the occurrence of vitiligo, Thus, it is necessary for understanding and treatment of vitiligo to fully and accurately understand pathophysiological states of full-thickness vitiliginous skin cells and tissues at different stages. This review aims to summarize research progress in the role of melanocytes and related cell populations in the occurrence of vitiligo.

Objective To analyze the abnormalities of local chemokines in patients with vitiligo and to explore the effect of tacrolimus on the secretion of chemokines in keratinocytes.Methods Blister fluids of 50 patients with vitiligo were collected,including lesion areas and normal areas.Luminex was used to analyze the concentration of local chemokines in patients with vitiligo to determine whether the chemokines were closely related to vitiligo.The effect of tacrolimus on chemokine secretion of was analyzed by Western blot in HaCaT cells.Results By Luminex analysis of blister fluid,it was found that CXCL9 and CXCL10 were significantly higher in the leukoplakia of vitiligo,and there was a significant difference,compared with the blister fluid in the normal site (P＜0.01).IFN-γ significantly stimulated the keratinocyte cell line HaCat to express CXCL9 and CXCL10.After pretreatment of HaCaT cells with 20 mg tacrolimus,the expression of CXCL9 and CXCL10 was significantly decreased,compared with the blank control (P＜0.01).Conclusions The leukoplakia chemokines CXCL9 and CXCL10 are highly expressed in vitiligo patients.The tacrolimus can significantly reduce the expression of CXCL9 and CXCL10 in keratinocytes under stress,and it therefore plays a therapeutic role in vitiligo.

Objective To analyze effects of tacrolimus on the secretion of chemokines CXCL9 and CXCL10 by γ-interferon (IFN-γ)-simulated HaCaT cells,as well as phosphorylated Janus kinase 1 (p-JAK1) and phosphorylated signal transducer and activator of transcription 1 (p-STAT1),and to explore the mechanism of tacrolimus in the treatment of vitiligo.Methods HaCaT cells were treated with l,10,20,40,60,80,100,120 mg/L tacrolimus solution separately for 4 hours,and methyl thiazolyl tetrazolium (MTT) assay was performed to evaluate the cellular proliferative activity.HaCaT cells were divided into 4 groups:blank control group receiving no treatment,IFN-γgroup treated with 500 U/ml IFN-γfor 12 or 48 hours,tacrolimus group treated with 20 mg/L tacrolimus for 4 hours,and tacrolimus + IFN-γgroup treated with 20 mg/L tacrolimus for 4 hours followed by the treatment with 500 U/ml IFN-γfor 12 or 48 hours.Real-time fluorescence-based quantitative PCR was conducted to measure the mRNA expression of CXCL9 and CXCL10,Western blot analysis to determine the protein expression of CXCL9,CXCL10,p-JAK1,and p-STAT1,and enzyme-linked immunosorbent assay (ELISA) to detect the levels of CXCL9 and CXCL10 in the culture supernatants of HaCaT cells.Results Tacrolimus at the maximum concentration of 20 mg/L had no effect on the proliferation of HaCaT cells (P ＞ 0.05).After the pretreatment with 20 mg/L tacrolimus,the mRNA expression of CXCL9 and CXCL10 significantly decreased from 10 369.08 ± 7.99 and 290.02 ± 2.16 to 5 914.33 ± 4.59 and 114.96 ± 0.73,respectively,after the treatment with IFN-γ(both P ＜ 0.01),and the protein expression of CXCL9,CXCL10,p-JAK1,and p-STAT1 also significantly decreased from 8.47 ± 0.29,7.87 ± 0.17,4.20 ± 0.18 and 4.29 ± 0.11 to 7.36 ± 0.13,7.36 ± 0.09,2.60 ± 0.16 and 3.62 ± 0.19,respectively,after the treatment with IFN-γ (all P ＜ 0.01).Moreover,the levels of CXCL9 and CXCL10 in the culture supernatants of HaCaT cells significantly decreased in the IFN-γgroup (1 213.36 ± 0.95,1 722.41 ± 2.57,respectively) compared with the tacrolimus + IFN-γ group (426.45 ± 0.31,554.12 ± 0.56,respectively,both P ＜ 0.01).Conclusion Tacrolimus can inhibit the secretion of CXCL9,CXCL10,p-JAK1 and p-STAT1 by HaCaT cells stimulated by IFN-γ.

Objective To evaluate the effect of human dermal mesenchymal stem cells (DMSCs) on the expression and secretion of interleukin (IL)-13 by perilesional CD8+ T lymphocytes from patients with vitiligo.Methods Tissue specimens were obtained from the perilesional region of six patients with active vitiligo,and CD8+ T lymphocytes were isolated from both the tissue specimens and peripheral blood of these patients.DMSCs and melanocytes were obtained from the foreskin tissue of healthy males.The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium,inner salt (MTS) assay was performed to estimate the effect of different concentrations of recombinant IL-13 on the proliferation of melanocytes,reverse transcripition-PCR and Western blotting to detect the mRNA and protein expressions of IL-13 in perilesional and peripheral blood CD8+ T lymphocytes respectively,real-time quantitative reverse transcription (RT)-PCR and enzyme-linked immunosorbent assay (ELISA) to detect the IL-13 mRNA expression in,and IL-13 protein expression in the culture supematant of,CD8+ T lymphocytes before and after coculture with DMSCs,respectively.Statistical analysis was done by t test.Results No obvious changes were observed in the proliferation of melanocytes treated with different concentrations (10,50,100,250,500 μg/L) of recombinant IL-13 for various durations (24,48,72 and 96 hours)compared with untreated melanocytes (all P ＞ 0.05).Both perilesional and peripheral blood CD8+ T lymphocytes expressed IL-13,and the expression was stronger in perilesional than in peripheral blood CD8+ T lymphocytes.A significant decrease was noted in IL-13 mRNA expression (0.100 0 ± 0.002 4 vs.0.383 2 ± 0.018 7,P ＜ 0.05) and protein level in the culture supernatant ((1 509.62 ± 48.44) ng/L vs.(5 507.98 ± 34.11) ng/L,P ＜ 0.05) of CD8+ T lymphocytes cocultured with DMSCs compared with monocultured CD8+ T lymphocytes.Conclusions There is a strong expression of IL-13 by perilesional CD8+ T lymphocytes in patients with vitiligo,which may be inhibited by DMSCs and serve as a target for the treatment of vitiligo.