Abstract:

Objective To establish a primary culture of human melanocytes from tiny skin sheets harvested by using a suction blister method, to carry out a serial subcultivation of the melanocytes with human amniotic membrane （AM） as a scaffold, and to observe the influence of AM on the adhesion, proliferation and dendrite development of melanocytes. Methods Tiny skin sheets were collected from the flexual forearm or lower abdomen of a healthy male volunteer by a suction blister method and melanocytes in the skin sheet were counted following Dopa staining under a microscope. The trypsinized skin sheets were scraped with a scalpel to harvest melanocytes which were subjected to a primary culture. Then, the melanocytes were inoculated onto fresh or cryopreserved AM followed by a culture for various durations （4, 8 and 12 days）. The morphology and dendrite development of melanocytes were visualized under an inverted microscope after dopa-staining, cell viability evaluated by MTT assay, the adhesion to AM examined by hematoxylin and eosin （HE） staining protocol. Results The density of melanocytes was 1543.1 ± 13.3 cells per mm2 and 857.4 ± 101.7 cells per mm2 in skin sheets obtained from the forearm flexure and lower abdomen of the volunteer, respectively. A skin sheet of about 25.1 mm2 from approximately two blister roof was required to ensure the success of primary culture of melanocytes within 1 month. After culture on fresh or cryopreserved AM for 4, 8, and 12 days, most melanocytes were bi-polar with extended slender dendrites compared with those cultured in common cell culture medium. HE staining showed that melancytes adhered and were evenly distributed on the basement membrane of AM. MTT assay showed that the AM inhibited the proliferation of melanocytes, and no statistical difference was observed in the inhibitory effect between fresh AM and cryopreserved AM （P > 0.05）. Conclusions Enriched with melanocyes, flexural forearm is a preferable donor site to offer skin sheets for primary culture of melanocytes. Human AM could improve the adhesive growth and dendrite development of melanocytes, and may serve as a promising bioscaffold for in vitro expansion of melanocytes.

Key words: vitligo