title: Dedifferentiation of human epidermal melanocytes into melanoblasts in vitro.
abstract: Melanoblasts (MB) are also called melanocyte (MC) precursor cells. In recent years, people have successfully cultivated human and mouse MB. Previous studies have shown that EDN3 induces cultivated bird MC to re-differentiate into double potential progenitor cells of MB. However, no study has reported whether in vitro cultivated human MC can be dedifferentiated. Our research on MC that were purified and cultivated in vitro found that adding 10 nm endothelin 1 (EDN1) (ET-1) to the MC medium without phorbol 12-myristate 13-acetate (PMA) induced a few MC to dedifferentiate and become a new type of cell. This new cell type was separated, purified, cloned and identified using multiple approaches. The results show that 88.7%, 8.69% and 2.5% of this new cell type were cells in the G(0) -G(1) , G(2) -M and S stages, respectively. The new cell type did not exhibit an apparent apoptotic peak, and its apoptotic rate was 0.09%. Stage I melanosomes were observed in the cytoplasm and were negative for the DOPA reaction. The cell surface antigen expression was positive for tyrosinase-related protein 2, negative or positive for c-kit and negative for S-100 and HMB45, showing that these cells were dedifferentiated MB of MC. Our findings provided evidence for atavism of mature human MC under certain conditions.
authors.affiliation: Department of Dermatology, the Affiliated of People's Hospital of Jiangsu University, Jiangsu, China. pfzzg5665ok@yahoo.cn
authors.forename: Zhiguo
authors.initials: Z
authors.lastname: Zhao
authors.forename: Cheng
authors.initials: C
authors.lastname: Jin
authors.forename: Keyun
authors.initials: K
authors.lastname: Ding
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Ge
authors.forename: Lllan
authors.initials: L
authors.lastname: Dai
mesh_terms: D017209:Apoptosis; D059447:Cell Cycle Checkpoints; D054337:Cell Dedifferentiation; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004295:Dihydroxyphenylalanine / Q000378:metabolism; D019332:Endothelin-1 / Q000494:pharmacology*; D006056:Golgi Apparatus / Q000378:metabolism; D006801:Humans; D019746:Intramolecular Oxidoreductases / Q000378:metabolism; D008544:Melanocytes / Q000166:cytology* / Q000187:drug effects* / Q000502:physiology; D058950:Melanoma-Specific Antigens / Q000378:metabolism; D020460:Melanosomes / Q000378:metabolism; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism; D009418:S100 Proteins / Q000378:metabolism; D058951:gp100 Melanoma Antigen
chemical_list: D019332:Endothelin-1; D058950:Melanoma-Specific Antigens; C548637:PMEL protein, human; D009418:S100 Proteins; D058951:gp100 Melanoma Antigen; D004295:Dihydroxyphenylalanine; D019009:Proto-Oncogene Proteins c-kit; D019746:Intramolecular Oxidoreductases; C042501:dopachrome isomerase