RESUMO
Background@#Phototherapy is an important method to treatvitiligo. However, it is unclear how phototherapy affectsmelanocyte precursors and skin neural crest stem cells. @*Objective@#To investigate the underlying mechanisms of narrow-band ultraviolet B (NB-UVB) induced melanocyte lineagedifferentiated from human scalp-derived neural creststem cells (HS-NCSCs). @*Methods@#HS-NCSCs were expandedfrom scalp hair follicles. The c-Kit−/CD57− HS-NCSCs wereisolated by cell sorting. Different doses of NB-UVB wereused to irradiate these HS-NCSCs. Cell ultrastructure was examinedby transmission electron microscope. Melanocytemarker expression was analyzed by Quantitative RT-PCRand Western blot. Cell proliferation and migration were alsoevaluated. @*Results@#The c-Kit−/CD57− HS-NCSCs expressedembryonic NCSC biomarkers. NB-UVB at a dose of 100 mJof NB-UVB had little effect on the cell proliferation of differentiatedmelanocytes from c-Kit−/CD57− HS-NCSCs, while700 mJ inhibited cell proliferation significantly. The dendriticprocesses of differentiated melanocytes increased afterradiation. The tyrosinase and Melanocortin 1 receptor (Mc1R)expression of differentiated melanocytes increased after NB-UVB exposure. The effect of NB-UVB on tyrosinase expressionwas modulated by signaling inhibitors H89 andPD98059 as well as Mc1R level in the cells. The migrationability of differentiated melanocytes was enhanced under100 mJ exposure. @*Conclusion@#These data demonstrate thatNB-UVB facilitates melanocytic differentiation of the HSNCSCsand enhances migration of these cells. Mc1R andcAMP pathway play a critical role in NB-UVB induced melanocyticdifferentiation.
RESUMO
Objective To investigate changes in expressions of activation antigens CD69 and HLA-DR in CD3+T lymphocytes in peripheral blood and skin lesions in patients with psoriasis vulgaris. Methods Peripheral blood samples were obtained from 20 patients with psoriasis vulgaris and 20 healthy controls, and skin specimens from the lesions of 15 out of the 20 patients and 10 healthy controls. Flow cytometry was performed to quantify the expressions of CD69 and HLA-DR in peripheral blood CD3+T cells, and an immunohistochemical study to measure the expression of HLA-DR in skin specimens. Statistical analysis was carried out by a two-sample t-test and Pearson correlation analysis with the SPSS 19.0 software. Results Compared with the healthy controls, the patients with psoriasis vulgaris showed increased expression rates of CD69 (4.70%± 1.90%vs. 1.56%± 0.95%, t=6.629, P<0.01)and HLA-DR (8.97%± 1.79% vs. 3.02% ± 1.15%, t= 6.204, P< 0.01)in peripheral blood. Pearson correlation analysis revealed that the percentage of CD3+HLA-DR+cells in peripheral blood was positively correlated with the psoriasis area and severity index (PASI)score (r=0.5626, P<0.05). The expression rate of HLA-DR was significantly higher in the dermis (64.87%± 17.31%vs. 19.80%± 5.69%, t=7.916, P<0.01), but lower in the epidermis(11.80%± 5.55%vs. 27.40%± 8.61%, t=5.479, P<0.01)in the psoriatic specimens compared with the control specimens. Immunohistochemically, HLA-DR was widely expressed in the dermis of psoriatic lesions, but mainly distributed around blood vessels in the control skin. Conclusions There is an aberrant activation of CD3+T cells in peripheral blood and inflammatory cells in skin lesions in patients with psoriasis vulgaris, and the percentage of CD3 +HLA-DR+ cells in peripheral blood is correlated with the severity of psoriasis vulagaris.