中波紫外线对角朊细胞合成SCF的作用

Ultraviolet B irradiation stimulates SCF expression from culured human keratinocytes

目的 研究中波紫外线对培养的角朊细胞合成干细胞因子的调节作用 ,阐明中波紫外线通过对角朊细胞分泌干细胞因子的调节而对黑素细胞的间接调控作用。方法 培养人角朊细胞 ,以中波紫外线 (30 2nm ,10 0mJ/cm2 )进行照射 ,采用原位杂交法测定干细胞因子的mRNA表达水平 ,采用免疫组化法测定干细胞因子在细胞内的蛋白合成水平。结果 正常皮肤表皮基底层和棘层的角朊细胞可合成SCF ;UVB照射后细胞内SCFmRNA表达量增加 ,但未见蛋白合成的增加。结论 实验结果提示SCF可能参与UVB照射引起的皮肤色素沉着 ,并减少UVB引起的黑素细胞的损伤及凋亡 ,维持皮肤内黑素细胞的数量稳定。

Objective The purpose of this study is to investigate the effects of UVB on stem cell factor( SCF) production from cultured human keratinocytes(KC)and provide experimental evidence that this cytokine is mitogen for human melanlocytes(MC)in UVB-induced melanosis.Methods Normal human KC were cultured and treated with UVB irradiation(302nm,100mJ/cm 2).The expression of SCF were measured by in situ hybridization and immunohistochemistry respectively.Results 1.The observation SCF expression in normal skin shows that SCF was expressed in part of basal and spinous KC.2.UVB irradiation can enhance SCF mRNA expression of culture KC but not protein expreession in cytoplasma.Conclusion Even though there is no significant difference of SCF protein expression in cytoplasma between normal and VUB-irradiation KC that may contribute to the greater release of SCF from UVB-irradiation KC,the finding of this sutdy suggest that SCF secreted by keratinocytes may play an essential role in UVB-induced pigmentation,protecting melanocyte from injury of UVB and the maintenance of melanocyte proliferating in the epidermis.