中文摘要：

目的观察肺泡Ⅱ型上皮细胞（AECⅡ）体外培养的生长状况及转分化过程。方法通过差速贴壁法对原代培养的AECⅡ进行分离、纯化,并将AECⅡ随机分为第0天、第2天、第4天、第6天、第8天8个时间点。利用倒置显微镜观察细胞生长情况,记录细胞数目,绘制生长曲线;锥虫蓝染色观察细胞活力;流式细胞仪观察细胞生长周期和细胞凋亡情况;电子显微镜观察细胞超微结构;采用免疫荧光技术,共聚焦显微镜观察肺表面活性蛋白（SP-C）、水通道蛋白5（AQP5）的阳性表达。结果倒置显微镜下第0天、第2天、第4天、第6天及第8天细胞数分别为（4.02±0.99）×108L-1、（10.41±0.24）×108L-1、（27.90±1.91）×108L-1、（27.12±0.85）×108L-1及（26.29±1.59）×108L-1,第2天与第0天、第4天与第2天细胞数比较差异均有统计学意义（Pa〈0.05）。第2天、第4天、第6天及第8天的细胞活力分别为（97.00±0.71）%、（97.20±0.84）%、（95.00±0.71）%及（92.80±1.30）%,第6天与第4天、第8天与第6天比较差异有统计学意义（Pa〈0.05）。细胞周期：空气组细胞G1期、S期细胞所占比率分别在第6天、第4天最高,但各时间点与前一时间点比较差异均无统计学意义（Pa〉0.05）。细胞凋亡：空气组Annexin-V＋/PI-亚群在第4天所占比例最高,与第2天及第6天比较差异均有统计学意义（Pa〈0.05）;Annexin-V＋/PI＋亚群细胞所占比例在第8天时最高,但与第6天比较差异无统计学意义（P〉0.05）,而第6天与第4天比较差异有统计学意义（P〈0.05）。细胞超微结构：第6天时可见介于AECⅡ和AECⅠ之间的中间状态细胞,此类细胞在细胞表面有微绒毛,但胞质内无板层小体或胞质内有板层小体但细胞表面无微绒毛。免疫荧光：第6天可见部分细胞胞质内有呈绿色荧光的SP-C阳性表达,荧光强度较第2天、第4天减弱,伴有胞膜点状分布的呈红色荧光的AQP5?

英文摘要：

Objective To observe the growing conditions and transdifferentiation of type Ⅱ alveolar epithelial cell（AECⅡ） in vitro. Methods Primarily culture AECⅡ were isolated and purified by differential adhesion methods,the cells were divided randomly into 0 day,2 days,4 days,6 days and 8 days groups,respectively.The growing conditions of AECⅡ and the cells number under the inverted microscope were recorded,the growth curve was drawn based on the cells number at every time point.Cell activity was observed with the typan blue dye exclusion method.The flow cytometry assayed the cell cycle and cell apoptosis,and the electron microscope was used to observe ultra cellular structures.The immunity fluorescence technology was used to observe the positive expression of surfactant protein C（SP-C） and aquaporin 5（AQP5） by laser confocal microscopy. Results The cell number at 0 day,2 days,4 days,6 days and 8 days was（4.02±0.99）×108L-1,（10.41±0.24）×108L-1,（27.90±1.91）×108L-1,（27.12±0.85）×108L-1and（26.29±1.59）×108L-1,respectively,the cell number was statistically different compared 2 days with 0 day and 4 days with 2 days（Pa0.05）.The cell activity at 2 days,4 days,6 days,8 days was（97.00±0.71）%,（97.20±0.84）%,（95.00±0.71）% and（92.80±1.30）%,respectively,the difference of cell activities was statistical significant compared 6 days with 4 days,8 days with 6 days（Pa0.05）.Cell cycle showed that in air group,the cell ratio of G1 phase and S phase were highest partly at 6 days and 4 days,but the ratio at each time spot had no statistical significant difference compared with preceding time spots（Pa0.05）.Cell apoptosis showed that in air group,the proportion of Annexin-V＋/PI-subgroups was highest at 4 days,but it had statistical significant difference compared with 2 days and 6 days（P0.05）.The Annexin-V＋/PI＋ subgroup cells accounted for the proportion to be highest at 8 days,and the difference had not statistically significant compared with 6 days（P0.05