In this review, guidelines and consensus for the diagnosis and treatment of vitiligo in Europe, the United States, Japan, South Korea, China and other countries and regions were compared in terms of clinical typing, staging, severity assessment, drug treatment and non-drug treatment of vitiligo, and similarities and differences in recommended treatments of vitiligo as well as emphasized concepts among these guidelines and consensus were summarized. It is hoped that this review will help clinicians provide more appropriate individualized treatment for patients with vitiligo.

Objective:To investigate the effect of KRT5 knockdown in keratinocytes on melanin content in co-cultured melanocytes, and to explain mechanisms underlying formation of hyperpigmented lesions in reticulate pigmented anomaly of the flexures (Dowling-Degos disease, DDD) .Methods:HaCaT cells with heterozygous mutations in the KRT5 gene were obtained by using clustered regularly interspaced short palindromic repeats (CRISPR) -CRISPR-associated protein 9 (Cas9) technology (experimental group) , and HaCaT cells transfected with non-targeting single guide RNA:Cas9 protein complex served as control group, both of which were in vitro co-cultured with primary human melanocyte cells (HEMn) separately. Immunofluorescence study was conducted to determine the expression of cytokeratin and melanosomes in co-cultured cells; melanin content was detected in melanocytes in different co-culture groups, which were obtained by differential trypsinization. Immunohistochemical study was performed to determine the expression of melanocyte-specific premelanosome protein 17 (Pmel17) in skin lesions in a patient with DDD carrying a KRT5 mutation and normal skin tissues in a healthy control. Results:Sanger sequencing showed a heterozygous mutation (c.1delA) at the initiation codon of exon 1 of the KRT5 gene in HaCaT cells in the experimental group, but no mutation in the KRT5 gene in the control group. Western blot analysis showed that the KRT5 protein expression was significantly lower in the experimental group (0.60 ± 0.05) than in the control group (1.00 ± 0.00, t = 32.38, P = 0.001) . Compared with the co-culture system in the control group, the number of Pmel17-labeled melanosomes markedly increased with the melanin content elevated by 52.5% ( t = -3.48, P = 0.025) in the HEMn cells co-cultured with HaCaT cells in the experimental group. Immunohistochemical study showed that the Pmel17 expression increased in the skin lesions in the DDD patient with KRT5 mutation compared with the normal skin tissues in the healthy control. Conclusion:The effect of HaCaT cells with CRISPR-Cas9-induced KRT5 mutation on the co-cultured HEMn melanocytes was verified by the successfully established in vitro co-culture system, which provides a primary cell model for further studies on interaction mechanisms between keratinocytes and melanocytes, and on pathogenesis of skin pigmentation abnormalities.

Objective:To establish a presenilin enhancer-2 (PSENEN) gene-silenced human immortalized keratinocyte (HaCaT) cell model, and to evaluate the effect of PSENEN gene silencing on the proliferation of and γ-secretase expression in HaCaT cells.Methods:Three shRNAs targeting the PSENEN gene were constructed, and inserted into the linearized LV3-pGLV-h1-GFP-puro vector to establish a recombinant lentiviral expression plasmid. After restriction enzyme digestion and sequencing, lentiviral packaging and purification were performed, and lentiviral titer was determined. Cultured HaCaT cells were divided into 5 groups: shRNA1, shRNA2 and shRNA3 groups treated with the lentivirus solutions containing PSENEN gene-targeted shRNA1, shRNA2 and shRNA3 respectively, NC group treated with the lentivirus solution containing a negative control shRNA (shNC) , and blank group treated without lentivirus solution. After transfection, inverted fluorescence microscopy was performed, and transfection efficiency was determined by flow cytometry. Cell counting kit-8 (CCK8) assay was performed to evaluate the effect of PSENEN gene silencing on the proliferation of HaCaT cells, and real-time fluorescence-based quantitative PCR (qPCR) and Western blot analysis were conducted to determine the mRNA and protein expression of PSENEN, nicastrin (NCT) , presenilin-1 (PS1) and anterior pharynx defective 1a (APH1a) genes respectively. Statistical analysis was carried out by using repeated measures analysis of variance, one-way analysis of variance, and least significant difference t test for multiple comparisons. Results:Inverted fluorescence microscopy showed that fluorescence was observed in the shRNA1 group, shRNA2 group, shRNA3 group and NC group, and flow cytometry showed that the transfection efficiency was over 98% in the above 4 groups. qPCR and Western blot analysis revealed that the mRNA and protein expression of PSENEN gene significantly decreased in the shRNA1 (0.187 ± 0.010, 0.219 ± 0.097, respectively) , shRNA2 (0.163 ± 0.022, 0.208 ± 0.014, respectively) and shRNA3 (0.174 ± 0.009, 0.185 ± 0.062, respectively) groups compared with the NC group (1.054 ± 0.272, 1.076 ± 0.075, respectively, all P < 0.001) . CCK8 assay showed that the cellular proliferative activity significantly increased in the shRNA1 group compared with the NC group at 0, 12, 36 and 48 hours (all P < 0.05) , and there was no significant difference between the 2 groups at 24 or 60 hours (both P > 0.05) ; the cellular proliferative activity was significantly higher in the shRNA2 and shRNA3 groups than in the NC group at 0, 12, 24, 36, 48 and 60 hours (all P < 0.05) . There was no significant difference in the mRNA expression of NCT, PS1 and APH1a genes among the shRNA1 group, shRNA2 group, shRNA3 group, NC group, and blank group ( F= 8.168, 4.644, 1.981, respectively, all P > 0.05) , while the relative protein expression level of mature NCT (mNCT) , immature NCT (imNCT) , carboxyl-terminal fragment of PS1 (PS1-CTF) and APH1a significantly differed among the above 5 groups ( F= 39.268, 5.929, 27.842, 20.663, respectively, all P ≤ 0.01) . Compared with the NC group, the shRNA1, shRNA2 and shRNA3 groups all showed significantly decreased protein expression of mNCT, PS1-CTF and APH1a (all P < 0.01) , but insignificant changes in imNCT protein expression (all P > 0.05) . Conclusion:The PSENEN gene-silenced HaCaT cell model was successfully constructed, and the PSENEN gene silencing could lead to an increase in the cellular proliferative activity of HaCaT cells and a decrease in the protein expression of γ-secretase subunits mNCT, PS1-CTF and APH1a.

Objective:To evaluate the effect of nicastrin (nct) gene on the biological functions of melanocytes in zebrafish.Methods:By using a morpholino oligonucleotide (MO) technology, a nct-MO sequence targeting the zebrafish nct mRNA was designed, so was a MO control (ctrl-MO) sequence. Then, the enhanced green fluorescent protein (EGFP) mRNA with MO target sequence at its 5′ end was synthesized, and co-microinjected with the nct-MO or ctrl-MO sequence into the zebrafish embryos to verify the silencing efficiency of nct-MO and observe changes in developmental phenotypes in zebrafish. With wild-type zebrafish as a blank control group, real-time fluorescence-based quantitative PCR (RT-PCR) was conducted to determine the mRNA expression of melanin synthesis-and notch signaling pathway-related genes, including mitfa, tyr, tyrp1a, tyrp1b, dct, pmela, notch1a, notch1b and hey1 genes. One-way analysis of variance was used for the comparison of means among multiple groups, and least significant difference (LSD) - t test for multiple comparisons. Results:Eight hours after zebrafish fertilization, green fluorescence was observed in the zebrafish embryos in the ctrl-MO+EGFP mRNA group, but not in the nct-MO+EGFP mRNA group or blank control group. Forty-eight hours after fertilization, the proportion of pigmented area among the whole area of the tail of zebrafish larvae was significantly lower in the nct-MO group (0.169 ± 0.083) than in the ctrl-MO group (0.258 ± 0.042, t=3.202, P=0.005) , and disorderly pigment distribution in the tails was observed in the nct-MO group. RT-PCR revealed significant differences in the mRNA expression of pmela, tyrp1a and hey1 genes among the nct-MO group, ctrl-MO group and blank control group (all P < 0.05) , but no significant difference was observed in the mRNA expression of mitfa, tyr, tyrp1b, dct, notch1a or notch1b genes among the 3 groups (all P>0.05) ; the relative expression levels of pmela and tyrp1a mRNAs were significantly lower in the nct-MO group (0.708 ± 0.028, 0.558 ± 0.136, respectively) than in the ctrl-MO group (1.023 ± 0.142, 1.016 ± 0.134, respectively, both P < 0.05) . Conclusion:The nct gene may affect biological functions of melanocytes by regulating melanin synthesis in zebrafish.

Objective:To evaluate the proliferative activity of and changes in the expression of related differentiation proteins in a stably NCSTN gene-silenced human immortalized keratinocyte cell line HaCaT, and to preliminarily explore the possible mechanism underlying the occurrence of acne inversa.Methods:By lentivirus-mediated short hairpin RNA (shRNA) , a NCSTN gene-silenced HaCaT cell model was established (shRNA group) , and other HaCaT cells transfected with empty lentivirus served as a negative control group. Real-time quantitative PCR and Western blot analysis were performed to determine the NCSTN gene-silencing efficiency. Cell counting kit-8 (CCK8) assay was conducted to evaluate the proliferative activity of HaCaT cells, and real-time quantitative PCR and Western blot analysis were performed to determine the mRNA and protein expression of cytokeratins (CK1, CK5, CK7, CK10, CK14, CK16, CK17, CK18, CK19 and CK20) and other differentiation molecules (involucrin and loricrin) respectively in HaCaT cells. Two-independent-sample t test was used to compare the measurement data between two groups. Results:NCSTN mRNA and protein expression were significantly lower in the shRNA group (0.42 ± 0.19, 0.30 ± 0.07 respectively) than in the negative control group (1.00 ± 0.34, 1.00 ± 0.26; t = 5.196, 2.637, P < 0.001, < 0.05, respectively) , and the gene-silencing efficiency was 70%. Compared with the negative control group, the shRNA group showed higher cellular proliferative activity, but decreased protein expression of CK16, CK19 and terminal differentiation molecule involucrin ( t = 3.787, 3.817, 2.904, P < 0.01, < 0.05, < 0.05, respectively) . Conclusion:Stable silencing of NCSTN gene can lead to abnormal proliferation and differentiation of HaCaT cells, which provides new ideas for subsequent exploration of acne inversa caused by NCSTN gene mutation.

Objective To construct a lentiviral vector delivering the Nicastrin (NCT) gene-targeted short hairpin RNA (shRNA) and determine gene-silencing efficiency of the vector in the human immortalized keratinocyte cell line HaCaT,and to construct a NCT gene-silenced HaCaT cell model to lay an experimental foundation for subsequently studying effects of NCT gene silencing on biological behavior of keratinocytes.Methods Three NCT gene-targeted shRNAs were designed and inserted into the pGLV3/ H1/GFP + Puro vector to construct three recombinant plasmids,which were then confirmed by sequencing.Recombinant plasmids combined with lentivirus packaging plasmids were co-transfected into 293T cells to obtain lentivirus particles,and the virus titer was determined.Cultured HaCaT cells were divided into 3 groups:blank group receiving no treatment,negative control group infected with the empty vector LV3-shNC,interference groups infected with lentivirus NCT-shRNA1,-shRNA2,-shRNA3,respectively.Flow cytometry was performed to determine transfection efficiency,and real-time fluorescence-based quantitative PCR (qRT-PCR) and Western blot analysis were conducted to determine efficiency of target gene silencing in HaCaT cells,so as to select the most efficient interference sequence.Results Sequencing analysis indicated that recombinant lentiviral vector NCT-shRNA was constructed successfully.After co-transfection of recombinant plasmids and lentivirus packaging plasmids into 293T cells,the titer of recombinant lentivirus particles was about 109 TU/ml.Flow cytometry showed that the transfection efficiency was greater than 95％.qRT-PCR revealed that the NCT mRNA expression was obviously down-regulated in the interference group compared with the negative control group,and NCT-shRNA1 was the most efficient sequence with interference efficiency being 75％.Western blot analysis showed that the inhibition rate of NCT protein expression was 71.7％ in the shRNA1 group compared with the negative control group.Conclusion The most efficient NCT-shRNA interference sequence is screened out,and the recombinant lentiviral vector NCT-shRNA and an NCT gene-silenced HaCaT cell model are both constructed successfully.

Three cases of dermatomyositis presenting with inverse Gottron's papules were reported.Of the 3 patients,there were 2 males and 1 female aged 43,41 and 46 years respectively,whose disease durations were 1,6,7 months respectively.Inverse Gottron's papules manifested as papules overlying the palmar aspect of the metacarpal and interphalangeal joints,which were arranged in a linear pattern in 2 cases.Of the 3 cases,1 presented with interstitial pneumonia,3 with myositis,and 2 showed negative anti-nuclear antibody test.Histopathological examination of inverse Gottron's papules in 1 case revealed focal liquefaction degeneration of basal cells and perivascular infiltration with inflammatory cells,especially lymphocytes,in the superficial dermis.The 3 patients received oral glucocorticoids and immunosuppressive agents in the early period of treatment.After 3-month treatment,clinical symptoms including muscle weakness and muscle pain were improved evidently,but no obvious improvement in inverse Gottron's papules was observed.After 1-year treatment,these papules on the palmar aspect were markedly relieved in 1 case.

Objective To analyze γ?secretase gene mutations in a pedigree with acne inversa. Methods Clinical data were collected from a pedigree with acne inversa, which contained 30 members spanning 4 generations. Of these members, 12 were affected by acne inversa, and 9 of the affected members were alive. Peripheral blood DNA was obtained from the proband, his seven relatives (including 4 affected and 3 unaffected members), and 100 unrelatedhealthy human controls. PCR was performed to amplify all the coding exons and their flanking sequences of the NCSTN, PSEN1, PSENEN, Aph1 genes followed by DNA sequencing. Results A heterozygous insertion mutation (c.229_230insCACC)of the PSENEN gene, which led to translational frameshifting and resulted in dysfunciton of the PSENEN protein, was detected in all the 5 patients, but not in unaffected members or healthy controls. Conclusion There is a novel heterozygous insertion mutation c.229_230insCACC in the PSENEN gene, which may be the molecular basis of acne inversa in this family.

Objective To measure expressions of nicastrin and its downstream Notch-HES signaling pathwayassociated proteins in skin lesions of patients with acne inversa harbouring nicastrin gene mutations.Methods An immunohistochemical study was performed to measure the expressions of nicastrin and Notch-HES signaling pathwayassociated proteins in paraffin-embeded skin samples from lesions of 4 patients with acne inversa and confirmed nicastrin mutations and from normal skin of 6 human controls.Spearman correlation analysis was carried out to assess the relationship between the expressions of nicastrin and Notch-HES signaling pathway-associated proteins.Results In normal control skin samples,nicastrin was widely distributed in the full-thickness epidermis and skin appendages such as pilosebaceous units,apocrine glands and eccrine glands.However,the expressions of nicastrin and Notch-HES signaling pathway-associated proteins were markedly decreased in the epidermis and hair follicle infundibulum in lesions of patients harbouring nicastrin gene mutations compared with normal control skin.Furthermore,nicastrin expression was positively correlated with Notchl,Notch3 and HES-1 expressions (r =0.831,0.748 and 0.807,P ＜ 0.01,0.05 and 0.01 respectively),but not significantly correlated with Notch2 or HES-5 expressions (r =0.597,0.591 respectively,both P ＞0.05).Conclusion Nicastrin expression markedly decreases in lesions of patients with acne inversa harbouring nicastrin gene mutations,and is positively correlated with the expressions of several Notch-HES signaling pathway-associated proteins,suggesting that the decrease in nicastrin expression may take part in the pathogenesis of acne inversa by influencing the expression of the downstream Notch-HES signaling pathway.

Objective To evaluate the safety and efficacy of a domestic recombinant human tumor necrosis factor receptor type Ⅱ- IgG Fc fusion protein (rhTNFR-Fc)for the treatment of moderate to severe psoriasis vulgaris. Methods A multicenter, randomized, double blind, parallel-group, positive drug-controlled clinical trial was conducted. According to random numbers generated by a hierarchical segmentation method using the SAS 9.2 software, patients with moderate to severe psoriasis vulgaris were randomly divided into two groups to be injected with two kinds of domestic rhTNFR-Fc under the trade names of Anbainuo(test group)and Yisaipu(control group)respectively at a dose of 25 mg twice a week for 12 consecutive weeks. The primary endpoint was the proportion of patients achieving a 50%, 75% and 90% reduction in psoriasis area and severity index(PASI50, PASI75 and PASI90)at week 2, 6 and 12 after initiation of the treatment. Adverse reactions were also recorded. Statistical analysis was carried out by using the chi-square test, Fisher′s exact test, two-sample t-test, and noninferiority trials with the software SAS 9.2. Results A total of 180 patients were enrolled in this study from 5 centers, and 174 completed this trial, of whom, 88 were assigned to the test group and 86 to the control group. Analysis of the full analysis set (FAS)revealed no significant differences in PASI50(75.6%(68/90)vs. 82.2%(74/90), P > 0.05)or PASI75(51.1%(46/90)vs. 50.0%(45/90), P > 0.05) between the test group and control group, but a significant increase in PASI90 in the test group compared with the control group (30.0% (27/90)vs.16.7% (15/90), χ2 = 4.472, P < 0.05)at week 12. Drug-related adverse reactions included elevation of transaminases, leukopenia, upper respiratory infections, injection-site reactions, abnormalities in urine routine test and purified protein derivative (PPD)skin test results, etc. There was no significant difference between the two groups in the incidence rate of adverse reactions(χ2 = 0.188, P > 0.05), most of which were mild, and subsided spontaneously or after appropriate treatment. Conclusion The domestic rhTNFR-Fc (trade name:Anbainuo)25 mg twice a week for 12 weeks is effective and safe for the treatment of moderate to severe psoriasis——————————vulgaris.