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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.
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Objective:To assess the value of culture of epidermal melanocytes from negative-pressure suction blisters in the auxiliary diagnosis of segmental vitiligo-like nevus depigmentosus.Methods:Between June 2019 and March 2020, 8 patients with segmental vitiligo-like nevus depigmentosus, who met the Coupe′s clinical diagnostic criteria, were enrolled from Department of Dermatology, Hangzhou Third People′s Hospital. All patients were evaluated by the Wood′s lamp, reflectance confocal microscopy (RCM) , 308-nm excimer laser radiation, and in vitro culture of epidermal melanocytes from negative-pressure suction blisters. Results:Among the 8 patients, fluorescence was observed in 6 under the Wood′s lamp, dermal papillary rings were incomplete or absent in 4 as shown by RCM, and 5 experienced no repigmentation after 308-nm excimer laser radiation. Among the 8 patients, in vitro cultured lesional melanocytes were all positive for ferrous sulfate staining, yellowish-white precipitates were obtained after digestion and centrifugation of the melanocytes, and stage Ⅰ-Ⅲ melanosomes were observed in the cytoplasm of melanocytes under the electron microscope; however, the precipitates were black in color after digestion and centrifugation of the melanocytes collected from the normal skin tissues at the contralateral anatomical site, and stageⅠ-Ⅳ melanosomes were seen in the cytoplasm of the melanocytes under the electron microscope. Conclusion:Culture of epidermal melanocytes from negative-pressure suction blisters may facilitate the diagnosis of segmental vitiligo-like nevus depigmentosus.
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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.
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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.
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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.
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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.
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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.
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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.
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Objective To evaluate the protective effect of WSY6 (a caffeic acid derivative) on hydrogen peroxide (H2O2)-induced oxidative stress injury in melanocytes,and to explore its potential molecular mechanism.Methods In vitro cultured human primary melanocytes were divided into 5 groups:control group receiving no treatment,H2O2 group treated with 1 mmol/L H2O2,6.25,12.5,25 μmol/L WSY6 groups pretreated with 6.25,12.5,25 μmol/L WSY6 respectively followed by 1-hour treatment with 1 mmol/L H2O2.After 24-hour treatment,MTS assay was performed to determine the survival rate of melanocytes,and the lactate dehydrogenase (LDH)kit was used to detect the LDH leakage level.Some melanocytes were divided into 2 groups:inhibitor group pretreated with the p38 inhibitor for 1 hour followed by 1-hour treatment with 1 mmol/L H2O2,and H2O2 group treated with 1 mmol/L H2O2 for 1 hour.After 24-hour treatment,the LDH kit was used to detect the LDH leakage level.Some other melanocytes were pretreated with 25 μmol/L WSY6 for 1,2,4 hours separately,followed by 1-hour treatment with H2O2.Then,flow cytometry was conducted to detect the level of intracellular reactive oxygen species (ROS).Some melanocytes were treated with 6.25,12.5,25 μmol/L WSY6 separately for 1 hour,followed by 1-hour treatment with H2O2.Then,Western bolt analysis was performed to determine the protein expression of cytochrome c (cyto-c),caspase-3,caspase-9,phosphorylated (p)-p38 MAPK,p-ERK and p-JNK.Results Compared with the control group,the H2O2 group showed significantly decreased survival rate of melanocytes (29.22％ ± 1.31％,P ＜ 0.05),but significantly increased intracellular LDH leakage level (47.19％ ± 4.85％,P ＜ 0.05),elevated intracellular ROS level (18.37 ± 1.59,P ＜ 0.05),and increased expression of caspase-3 and caspase-9.Compared with the H2O2 group,the 6.25,12.5,25 μmol/L WSY6 groups showed significantly increased cell survival rate (52.48％ ± 1.17％,60.21％ ± 0.25％,78.32％ ± 1.73％,P ＜ 0.05),but significantly decreased LDH leakage level (21.99％ ± 0.22％,15.38％ ± 0.45％,13.18％ ± 0.38％,P ＜ 0.05),and the intracellular ROS level was significantly decreased in the 25 μmol/L WSY6 group after 1,2,4 hours of treatment (7.59 ± 1.00,6.22 ± 0.52,5.1 ± 0.48,P ＜ 0.05).The LDH leakage level in melanocytes was significantly lower in the p38 inhibitor group than in the H2O2 group (P ＜ 0.05).Western blot analysis revealed that after the pretreatment with 6.25,12.5,25 μmol/L WSY6 separately,the WSY6 groups all showed obviously decreased expression of caspase-3,caspase-9 and p-p38 compared with the H2O2 group.However,there was no obvious difference in the expression of p-ERK and p-JNK between the WSY6 groups and the H2O2 group.Besides,the WSY6 groups showed decreased expression of p-p53 (a downstream product of p38 MAPK),which decreased along with the increase in the concentration of WSY6.Conclusion WSY6 shows a markedly protective effect on H2O2-induced oxidative stress injury in melanocytes,likely through the p38 MAPK pathway.
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Objective To investigate the value of the severity of isomorphic response at the donor site in evaluation of the therapeutic effect of cultured melanocyte transplantation.Methods A total of 172 vitiligo patients,who received cultured melanocyte transplantation or non-cultured epidermal suspension transplantation at the Department of Dermatology of Hangzhou Third Hospital from May 2008 to August 2016 and developed isomorphic response at the donor site,were enrolled into this study.According to the area of isomorphic response,these patients were divided into 2 groups:incomplete isomorphic response group whose area of isomorphic response was less than the suction area,and complete isomorphic response group whose area of isomorphic response was equal to the suction area.The correlation between therapeutic effects of melanocyte transplantation and isomorphic response was analyzed.Results Of the 172 patients,83 had incomplete isomorphic response,and 89 had complete isomorphic response at the donor site.In the incomplete isomorphic response group,21 (25.3％) patients were cured,and 17 (20.5％) were markedly improved,while 4 (4.5％) patients were cured,and 11 (12.4％) were improved in the complete isomorphic response group.Additionally,the response rate was significantly higher in the incomplete isomorphic response group than in the complete isomorphic response group (45.8％ vs.16.9％,x2 =31.581,P ＜ 0.001).Furthermore,the duration of stable phase was also significantly longer in the incomplete isomorphic response group than in the complete isomorphic response group (18.5 ± 15.3 months vs.10.2 ± 7.3 months,t =4.581,P ＜ 0.001).Correlation analysis showed that the duration of stable phase,which was classified into 5 grades including 6-11 months,12-23 months,24-35 months,36-47 months and ≥ 48 months,was negatively correlated with the severity (incomplete or complete) of isomorphic response (rs =-0.322,P ＜ 0.001),but positively correlated with repigmentation rates of the skin lesions (rs =0.675,P ＜ 0.001).Conclusion The length of duration of stable phase is an important factor affecting the therapeutic effect of melanocyte transplantation in vitiligo patients with isomorphic response at the donor site,and the severity of isomorphic response can indicate the length of duration of stable phase and predict the therapeutic effect of melanocyte transplantation.
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Objective To investigate the value of the severity of isomorphic response at the donor site in evaluation of the therapeutic effect of cultured melanocyte transplantation.Methods A total of 172 vitiligo patients,who received cultured melanocyte transplantation or non-cultured epidermal suspension transplantation at the Department of Dermatology of Hangzhou Third Hospital from May 2008 to August 2016 and developed isomorphic response at the donor site,were enrolled into this study.According to the area of isomorphic response,these patients were divided into 2 groups:incomplete isomorphic response group whose area of isomorphic response was less than the suction area,and complete isomorphic response group whose area of isomorphic response was equal to the suction area.The correlation between therapeutic effects of melanocyte transplantation and isomorphic response was analyzed.Results Of the 172 patients,83 had incomplete isomorphic response,and 89 had complete isomorphic response at the donor site.In the incomplete isomorphic response group,21 (25.3％) patients were cured,and 17 (20.5％) were markedly improved,while 4 (4.5％) patients were cured,and 11 (12.4％) were improved in the complete isomorphic response group.Additionally,the response rate was significantly higher in the incomplete isomorphic response group than in the complete isomorphic response group (45.8％ vs.16.9％,x2 =31.581,P ＜ 0.001).Furthermore,the duration of stable phase was also significantly longer in the incomplete isomorphic response group than in the complete isomorphic response group (18.5 ± 15.3 months vs.10.2 ± 7.3 months,t =4.581,P ＜ 0.001).Correlation analysis showed that the duration of stable phase,which was classified into 5 grades including 6-11 months,12-23 months,24-35 months,36-47 months and ≥ 48 months,was negatively correlated with the severity (incomplete or complete) of isomorphic response (rs =-0.322,P ＜ 0.001),but positively correlated with repigmentation rates of the skin lesions (rs =0.675,P ＜ 0.001).Conclusion The length of duration of stable phase is an important factor affecting the therapeutic effect of melanocyte transplantation in vitiligo patients with isomorphic response at the donor site,and the severity of isomorphic response can indicate the length of duration of stable phase and predict the therapeutic effect of melanocyte transplantation.
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Objective To investigate the relationship between the efficacy of autologous cultured melanocyte transplantation and serum levels of interleukin-17 (IL-17) and FoxP3 in patients with vitiligo.Methods Forty patients with stable vitiligo vulgaris were included in this study,and received autologous cultured melanocyte transplantation.Six months after the transplantation,treatment efficacy was evaluated,and patients were classified into the successfully treated group (n =25) and unsuccessfully treated group (n =15).Peripheral blood was collected from all the patients before the transplantation,and enzyme-linked immunosorbent assay (ELISA) was performed to measure the serum levels of IL-17 and FoxP3.Statistical analysis was done using two independent samples t-test with the SPSS software (version 17.0).Results The successfully treated patients showed lower serum levels of IL-17 ((15.29 ± 7.86) vs.(43.88 ± 13.02) ng/L,P ＜ 0.05),but higher serum levels of FoxP3 ((6.08 ± 2.03) vs.(3.37 ± 1.81) ng/L,P ＜ 0.05) than the unsuccessfully treated patients.Conclusion The increased serum IL-17 and decreased serum FoxP3 may contribute to the failure of autologous cultured melanocyte transplantation in patients with vitiligo.
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Objective To investigate the effect of nuclear translocation of E2p45 related factor 2 (Nrf2)on the biological activity of melanocytes.Methods Plasmid vectors containing wild-type nrf2 gene (pcDNA-nrf2) and nls-deleted nrf2 gene (pcDNA-nrf2△nls) were constructed.B10BR normal murine melanocytes were classified into three groups,i.e.,untransfected group,wild-type nrf2 group transfected with pcDNA-nrf2,and mutated nrf2 group transfected with pcDNA-nrf2△nls.Each of the above groups were further divided into three subgroups:control subgroup receiving no treatment,hydrogen peroxide (H2O2) subgroup treated with H2O2 of 200 μmol/L for 24 hours,and combined subgroup pretreated with tert-butyl hydroquinone (TBHQ) followed by treatment with H2O2 of 200 μmol/L for 24 hours.Subsequently,methyl thiazolyl tetrazolium (MTT) assay was performed to evaluate the proliferative activity of cells,dopa oxidation assay to determine tyrosinase activity,Transwell assay to estimate cell migration ability,Western blot to quantify the expressions of Nrf2 and his tag fusion protein.Results TBHQ significantly enhanced the nuclear expression of Nrf2 in B10BR cells transfected with pcDNA-nrf2 or pcDNA-nrf2△nls (both P ＜ 0.01).No significant difference was observed in tyrosinase activity between untreated wild-type nrf2 group,mutated nrf2 group,and untransfected group (P ＞ 0.05).There was a statistical decrease in tyrosinase activity in the two H2O2-treated transfected groups compared with the untreated transfected groups (both P ＜ 0.05),and the decrease was reversed by TBHQ pretreatment in the wildtype nrf2 group (P ＜ 0.05),but not in the mutated nrf2 group (P ＞ 0.05).Further more,the proliferative activity of B10BR cells experienced no obvious changes in the wild-type nrf2 group (P ＞ 0.05),but was significantly reduced in the untransfected group (P ＜ 0.05) and mutated nrf2 group (P ＜ 0.01) after the H2O2 treatment compared with the corresponding untreated groups.TBHQ could protect the pcDNA-nrf2-transfected B10BR cells,but not pcDNA-nrf2△nls-transfected B10BR cells,from H2O2-induced oxidative damage.Transwell assay showed no significant difference in migration ability among these nine groups (P ＞ 0.05).Conclusions Abnormal nuclear translocation of Nrf2 could affect antioxidant activity of,proliferative activity of and tyrosinase activity in melanocytes.TBHQ may enhance the tyrosinase activity in,proliferative activity and antioxidant activity of melanocytes via activating the nuclear expression of wild type Nrf2.
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Objective To evaluate the effect of calcipotriol on the proliferation of and cytokine secretion by melanocytes and perilesional CD8+ cytotoxic T lymphocytes (CTLs) from patients with vitiligo.Methods Melanocytes isolated from abdominal skin and CD8+ CTLs from perilesional skin of patients with vitiligo were subjected to successive culture in vitro.After several passages,the melanocytes and CD8+ CTLs were cultured alone or in combination with or without the presence of various concentrations of calcipotriol for 24 to 48 hours.MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfopheny)-2H-tetrazolium,inner salt) method was used to evaluate the proliferative activity of cells,enzyme-linked immunosorbent assay to determine the levels of interleukin (IL)-6,tumor necrosis factor (TNF)-α and interferon (IFN)-γ in the culture supematant of cells,flow cytometry to detect cell apoptosis.Some co-cultured melanocytes and CTLs were treated with calcipotriol of 10-8 mol/L and anti-IL-6 antibody of various concentrations (0,1,2,2.5,5,10 mg/L) for two days followed by enumeration of cells.The concentrations of 108 and 10-9 mol/L (calcipotriol) were chosen for relevant tests.Results There was a marked apoptosis in MCs after coculture with CD8+ CTLs.The 24-hour treatment with calcipotriol of 104 and 10-9 mol/L had no obvious effect on the proliferation of melanocytes cultured alone (both P ＞ 0.05),but accelerated the proliferation of melanocytes cocultured with CTLs (both P ＜0.05) as well as that of CD8+ CTLs cultured alone or in combination with melanocytes (all P ＜0.05).A statistical decrease was observed in IL-6,TNF-α and IFN-γlevels in the supernatant of cocultured melanocytes and CTLs compared with those in the supernatant of melanocytes and CTLs cultured alone,and calcipotriol of 10-9 mol/L intensified the decrease in supernatant IL-6 level (t =2.89,P ＜0.05),but no statistical changes were noted for the level of TNF-α or IFN-γin the supernatant of the coculture system after treatment with calcipotriol of 104 or 104 mol/L compared with that before treatment (both P ＞ 0.05).In the coculture system pretreated with calcipotriol of 10-8 mol/L,the number of CD8+ CTLs significantly decreased (t =3.15,P ＜0.05),whereas that of melanocytes significantly increased (t =3.53,P ＜0.05) after the treatment with anti-IL-6 antibody of 5 mg/L.Conclusions Perilesional CD8+ CTLs have a specific cytotoxic effect on melanocytes,and calcipotriol may inhibit the cytotoxic effect of CD8+ CTLs by suppressing the secretion of IL-6,which may partly explain the therapeutic mechanism of calcipotriol for vitiligo.
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Objective To investigate the intracellular signal transduction pathways involved in the protective effect of nicotinic acid against ultraviolet B(UVB)-induced damage in human skin keratinocytes.Methods Cultured human keratinocyte HaCaT cells were divided into several groups to be treated with nicotinic acid,UVB irradiation,LY294002(an inhibitor of Akt),U0126(an inhibitor of extracellular signal-regulated kinase(ERK)1/2),SB203580(an inhibitor of P38)alone or in combination for different durations.Then,Western blot was performed to quantify the phosphorylation levels of the protein kinase B(Akt)/MAPK pathwayassociated proteins including Akt,P38,JNK and ERK1/2,MTT assay to evaluate the activity of HaCaT cells,enzyme-linked immunosorbent assay to determine the levels of endothelin-1(ET-1)and basic fibroblast growth factor(bFGF)in the culture supernatant of HaCaT cells,and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling(TUNEL)to evaluate the apoptosis in HaCaT cells.Results As Western blot showed,phosphorylated Akt,P38,JNK and ERK1/2 were markedly activated within 60 minutes after pretreatment with nicotinic acid and irradiation with UVB(all P ＜ 0.01),and the activation was more significant for phosphorylated Akt,P38,and ERK1/2 within 2 hours(all P ＜ 0.01).Nicotinic acid effectively suppressed the UVB-induced cell death and apoptosis in HaCaT cells.The levels of supernatant ET-1 and bFGF were significantly decreased in HaCaT cells treated with the above 3 inhibitors followed by UVB irradiation than in those treated with the inhibitors alone(all P ＜ 0.05),and nicotinic acid pretreatment only reversed the decrease in supernatant bFGF in HaCaT cells treated with SB203580 followed by UVB irradiation.Conclusion The Akt signaling pathway may play a regulatory role in the protection by nicotinic acid against UVB-induced damage in HaCaT cells.
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Objective To express and purify the epitope peptide of human melanin-concentrating hormone receptor 1, and to evaluate its performance in the detection of autoantibodies in vitiligo patients. Methods The target gene encoding the epitope peptide of human melanin-concentrating hormone receptor 1 was synthesized, cloned to prokaryotic expression vector pGEX-4T-2 which was then transferred to E. coli BL21. The protein expression was induced by isopropy-β-D-thiogalactoside (IPTG) and identified with sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot. Blocking ELISA was carried out with membrane proteins extracted from melanocytes as the blocking antigen. The antigenicity of the peptide was detected in sera from 100 patients with progressive vitiligo and 30 healthy human controls. Results The recombinant expression vector was successfully constructed, and the target protein was successfully expressed in E.coli, which was evidenced by SDS-PAGE and Western blot. With the glutathione S-transferase (GST) purification kit, the purity of the recombinant protein reached 100% when the sampling weight was less than 0.625 μg.The binding of the target protein with serum IgG antibodies from vitiligo patients could be blocked by natural membrane antigen of melanocytes. Of the 100 sera from patients with progressive vitiligo, 36 were reactive with the target protein. Conclusions The epitope peptide of human melanin-concentrating hormone receptor 1 has been successfully expressed and purified. The purified protein can bind with serum IgG antibodies from vitiligo patients, and may be applied to the detection of autoantibodies against human melanin-concentrating hormone receptor 1.
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Objective To investigate quercetin's protective effect against oxidative stress in and impact on the biological activity of mouse B10BR melanocytes. Methods B10BR cells were cultured and treated with different concentrations of quercetin followed by additional culture. Then, cell viability was measured by using MTT assay, hydrogen peroxide-induced cell apoptosis by flow cytometry, and cell morphological changes by microscopy. The tyrosinase activity in and melanin synthesis by B10BR cells were measured by dopa oxidation assay and sodium hydroxide (NaOH)-lysis method, respectively. Results After treatment with quercetin of 33.33 μmol/L for 24 hours, the survival rate of B10BR cells reached (94.22 ± 3.36)%, tyrosinase activity (107.15 ± 10.96)%, and melanin content (111.85 ± 9.49)%. A significant difference was observed in tyrosinase activity and melanin content between hydrogen peroxide-induced and 33.33 μmol/L quercetin-treated B10BR cells and those only induced by hydrogen peroxide (both P < 0.01). Flow cytometry revealed that quercetin inhibited hydrogen peroxide-induced apoptosis in melanocytes. Conclusion The protective effect of quercetin against hydrogen peroxide-induced apoptosis in melanocytes may provide a new idea for the treatment of vitiligo.