Kalina M, Levi D, Riklis S
Department of Histology and Cell Biology, Sackler School of Medicine, Tel Aviv University, Ramat Aviv, Israel.
Histochemistry. 1990;95(1):97-103. doi: 10.1007/BF00737233.
Alveolar type II like cells (ALT II) represent a small subpopulation of alveolar type II cells, which is able to proliferate, can be passaged and possess many characteristics of differentiated adult type II cells. A correlation was found between the growth and development of ALT II cells in culture and their alkaline phosphatase activity. Unlike alveolar type II cells, which lose the activity in culture, ALT II cells regain the activity and maintain it for a long culture period. Quantitative histochemical analysis of the stained cells indicate that 80% of the cells at days 15-20 in culture are alkaline phosphatase positive. Inhibition studies indicate that alkaline phosphatase from ALT II cells and freshly isolated type II cells were similar. The inhibition of ALT II alkaline phosphatase by L-levamisole and its heat stability are similar to that of the bone enzyme and differ from the intestinal enzyme. Alkaline phosphatase expression is considered part of the differentiated phenotype of these cells. Therefore, the presence of this enzyme in ALT II cells adds support to the notion that these cells maintain many aspects of mature alveolar type II cells.
肺泡II型样细胞（ALT II）是肺泡II型细胞中的一个小亚群，能够增殖、传代，并具有许多分化成熟的II型细胞的特征。在培养的ALT II细胞的生长发育与其碱性磷酸酶活性之间发现了一种相关性。与在培养中失去活性的肺泡II型细胞不同，ALT II细胞恢复了活性并在长时间培养中保持该活性。对染色细胞的定量组织化学分析表明，培养15 - 20天时80%的细胞碱性磷酸酶呈阳性。抑制研究表明，ALT II细胞和新鲜分离的II型细胞的碱性磷酸酶相似。L - 左旋咪唑对ALT II碱性磷酸酶的抑制作用及其热稳定性与骨酶相似，与肠酶不同。碱性磷酸酶表达被认为是这些细胞分化表型的一部分。因此，ALT II细胞中这种酶的存在支持了这些细胞维持成熟肺泡II型细胞许多方面特征的观点。
