Protective effects of tea polyphenols against the destruction of melanocytes by CD8+ T ceils from vitiligo patients / 中华皮肤科杂志

ABSTRACT

Objective To evaluate the protective effects of tea polyphenols against the destruction of melanocytes by CD8+ T cells from vitiligo patients.Methods Skin tissue was resected from the margin of vitiligo lesions followed by the isolation and culture of CD8+ T lymphocytes,and from the normal skin of vitiligo patients followed by the isolation and culture of melanocytes.Flow cytometry was carried out to evaluate the purity of CD8+ T cells.The melanocytes were cocultured with the CD8 + T cells at different ratios followed by the evaluation of killing effect of CD8+ T cells.Various concentrations (200 and 400 μg/ml) of tea polyphenols were added into the co-culture system of CD8+ T cells and melanocytes at a ratio of 5 ∶ 1 followed by an additional culture of 48 hours.Then,flow cytometry was performed to detect the apoptosis in melanocytes in the coculture system.Results CD8+ T lymphocytes were successfully obtained from the marginal area of vitiligo lesions with a purity of more than 90％,which highly expressed the antigens CD137 and CD69.The coculture with CD8+ T cells markedly accelerated the apoptosis in melanocytes,while the accelerative effect was inhibited by tea polyphenols of 200 and 400 μg/ml.Conclusions The CD8+ T cells infiltrating the edge of vitiligo lesions display a potential destructive effect on autologous melanocytes from vitiligo patients,and tea polyphenols have a protective effect against the destruction of melanocytes by CD8+ T cells.