Effect of granulocyt e colony-stimulating factor and its receptor on the proliferation and tyrosinase activity of human melanocytes / 中华皮肤科杂志

ABSTRACT

Objective To measure the expression of granulocyte colony-stimulating factor receptor (G-CSFR) in human melanocytes and to evaluate the biologic effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on human melanocytes.Methods Melanocytes were obtained from circumcision specimens of healthy males,and neutrophils were isolated from heparin-andcoagulated peripheral blood of healthy human followed by a primary culture.Then,the melanocytes in third passage were cultured with or without the presence of various concentrations (200,400,600,800 μg/L) of rhG-CSF for 72 hours.The growth and morphology of melanocytes were observed.Flow cytometry was performed to detect the expression of G-CSFR in untreated human melanocytes,neutrophils and erythroleukemia cells (HEL 92.1.7).Western blot and reverse transcription PCR (RT-PCR) were carried out to measure the expression of G-CSFR protein and mRNA respectively in the neutrophils,HEL 92.1.7 cells,treated or untreated human melanocytes.Methyl thiazolyl tetrazolium (MTT) assay was performed to evaluate the proliferation,and dopa-oxidation assay to estimate the tyrosinase activity,of treated melanocytes.Results The expression rate of G-CSFR was 76.81％ ± 10.70％ in human melanocytes,significantly higher than that in the HEL 92.1.7 cells (2.53％ ± 1.54％,P ＜ 0.01 ),but lower than that in the neutrophils (85.76％ ± 15.71％,P ＜ 0.05).Both G-CSFR protein and mRNA were expressed in melanocytes,and there was no significant differences in the expression level of G-CSFR protein and mRNA among melanocytes treated with different concentrations of rhG-CSF (both P ＞ 0.05).The expression levels of G-CSFR protein and mRNA in the melanecytes were significantly higher than those in the HEL 92.1.7 cells (both P ＜ 0.01 ),but lower than those in the neutrophils (P ＜ 0.05 or ＜ 0.01 ).rhG-CSF at 200-800 μg/L displayed a significantly promotive effect on the proliferation of melanocytes (P ＜ 0.01 or ＜ 0.05 ),and the effect was in a dose-dependent manner when rhG-CSF ranged from 200 to 600 μg/L (P ＜ 0.01 ).The rhG-CSF at 600 μg/L and 12-O-tetradecanoyl-phorbol-13-acetate (TPA) at 20 μg/L showed an equivalent effect on the proliferation of melanocytes (164.04％ ± 13.0％ vs.165.62％ ± 10.6％,P ＞ 0.05).However,rhG-CSF from 200 to 800 μg/L had no significant impact on the tyrosinase activity of melanocytes (all P ＞ 0.05 ).Conclusions G-CSFR is expressed in human melanocytes. rhG-CSF can promote the proliferation of cultured human melanocytes,but has no obvious influence on the tyrosinase activity of melanocytes.