目的:探讨外胚层发育不良A1（ectodysplasin-A1，EDA1）蛋白对类成釉上皮细胞（ameloblast-like epithelial cell，LS8细胞）增殖和细胞周期的影响。方法:用野生型EDA1基因质粒pCR3-Flag-EDA1-W（野生组）、综合征型突变EDA1基因质粒pCR3-Flag-EDA1-H252L（突变组）及空载体质粒pCR3-Flag（对照组）转染LS8细胞，培养0、24、48、72、96 h时噻唑蓝法检测各组细胞增殖活性（n A值），流式细胞术检测各组细胞周期，上述实验重复3次。n 结果:培养72 h，与对照组（0.105±0.032）相比，野生组细胞增殖活性（0.201±0.009）显著增加（n P<0.05）；培养96 h，与对照组（0.168±0.054）及突变组（0.194±0.059）相比，野生组细胞增殖活性（0.386±0.066）显著增加（n P0.05）。与对照组（65.4%±2.1%）及突变组（66.6%±3.1%）相比，野生组Gn 0/Gn 1期细胞分布比例（51.2%±1.1%）显著降低（n P<0.01）；与对照组（23.1%±2.0%）及突变型组（21.9%±1.8%）相比，野生型组S期细胞分布比例（37.3%±2.4%）显著升高（n P0.05）。n 结论:野生型EDA1基因可促进LS8细胞增殖，并促进Gn 0/Gn 1期细胞向S期转化；综合征型突变EDA1基因（EDA1-H252L）使EDA1蛋白促进细胞增殖和调控细胞周期的功能丧失。n “,”Objective:To investigate the effects of ectodysplasin-A1 (EDA1) on the proliferation and cell cycle of ameloblast-like epithelial cells (LS8 cells).Methods:Wild EDA1 plasmid pCR3-Flag-EDA1-W (wild group), syndrome mutant EDA1 plasmid pCR3-Flag-EDA1-H252L (mutant group) and empty vector plasmid pCR3-Flag (control group) were transfected into LS8 cells. Cell proliferation was detected by methyl thiazolyl tetrazolium (MTT) assay and cell cycle was detected by flow cytometry. All tests were repeated three times.Results:Compared with the control group (0.105±0.032), the proliferation activity of the wild group (0.201±0.009) was significantly higher after 72 h (n P<0.05). Compared with the control group (0.168±0.054) and the mutant group (0.194±0.059), the proliferation activity of the wild group (0.386±0.066) was significantly higher after 96 h (n P0.05). In the Gn 0/Gn 1 phase, compared with the control group (65.4%±2.1%) and the mutant group (66.6%±3.1%), the cell distribution ratio of the wild group (51.2%±1.1%) was significantly lower (n P<0.01). In the S phase, compared with the control group (23.1%±2.0%) and the mutant group (21.9%±1.8%), the cell distribution ratio of the wild type group (37.3%±2.4%) was significantly higher (n P<0.01). There was no significant difference in cell cycle distribution between the mutant group and the control group (n P<0.05).n Conclusions:Wild EDA1 promotes the proliferation of LS8 cells and the transformation from Gn 0/Gn 1 to S phase. The syndrome mutant EDA1 (EDA1-H252L) loses its function of regulating the cell proliferation and cell cycle of LS8 cells.n