角质形成细胞与成纤维细胞对中波紫外线照射应激能力的比较研究

Reactive abilities of keratinocytes and fibroblasts to UVB

目的:观察两种皮肤细胞即原代角质形成细胞及成纤维细胞对中波紫外线照射的反应差异。方法:采用不同剂量中波紫外线(UVB)照射上述两种细胞,评估UVB对细胞作用的时间及剂量效应,以倒置光学显微镜观察细胞受损程度,MTT法检测细胞活性。结果:UVB照射后,细胞损伤程度均随照射剂量加大而加重。另经24、48、72小时孵育后,分别对两种细胞进行不同时间段的细胞活性(MTT)比值比较(72/24小时,72/48小时),发现细胞活性比依次递减:原代角质形成细胞(1.16和1.63),成纤维细胞(1.05和1.09)。MTT结果显示低剂量紫外线照射时,细胞损伤恢复可发生在照射后48小时;高剂量紫外线照射后,细胞的损伤程度均随孵育时间延长而加重。结论:原代角质形成细胞抵抗紫外线辐射损伤的能力较强,而成纤维细胞相对较易受损。

Objective To investigate and compare effects of UVB on human primary keratinocytes(KC) and fibroblasts. Methods Two types of above cells were irradiated with different dosages of UVB and /or were cultured for different time intervals. Light microscopy was used for morphology change, cell count for cell proliferation, MTT for the cellular activity. Results Compared with sham-irradiation, primary KC and fibroblasts irradiated with UVB were damaged on the morphology, cell growth was inhibited and cellular activity was decreased. The UVB irradiation effects were proved to be dose- and time-dependent.The cellular activity ratio calculated from MTT readings of various time intervals (72h/24h and 72h/48h ) was different among above 3 types of cells. The MTT ratio showed a decrease in order of primary KC (1.16 and 1.63), fibroblasts (1.05 and 1.09). In addition, there was a recovery by the 48 h culture after irradiation if irradiated dosage was low (30～60 mJ/cm2 for UVB),but there was an increased photodamage with culturing time to the 72 h in high dosage of UVB irradiation(≥60mJ/cm2). Conclusion The photodamage from UVB irradiation on primary KC and fibroblasts shows both dose and time dependence. As to the resistant ability to UVB irradiation among the two types of cells, the MTT ratio showed a decrease in order of primary KC and fibroblasts.