Pruitt S C
Roswell Park Cancer Institute, Department of Molecular and Cellular Biology, Buffalo, NY 14263.
Development. 1992 Nov;116(3):573-83. doi: 10.1242/dev.116.3.573.
A P19 embryonal carcinoma stem cell line carrying an insertion of the E. coli LacZ gene in an endogenous copy of the Pax-3 gene was identified. Expression of the Pax-3/LacZ fusion gene in neuroectodermal and mesodermal lineages following induction of differentiation by chemical treatments (retinoic acid and dimethylsulfoxide) was characterized using this line and is consistent with the previous localization of Pax-3 expression in the embryo to mitotically active cells of the dorsal neuroectoderm and the adjacent segmented dermomyotome. Pax-3/LacZ marked stem cells were also utilized as target cells in mixing experiments with unmarked P19 cells that had been differentiated by pretreatment with chemical inducers. Induction of beta-galactosidase and neuroectodermal markers in the target cells demonstrates that: (1) some differentiated P19 cell derivatives transiently express endogenous Pax-3- and neuroectoderm-inducing activities, (2) undifferentiated target stem cells respond to these activities even in the presence of leukemia inhibitory factor and (3) the endogenous activities can be distinguished from, and are more potent than, retinoic acid treatment in inducing neuroectoderm. These observations demonstrate that P19 embryonal carcinoma cells provide a useful in vitro system for analysis of the cellular interactions responsible for neuroectoderm induction in mammals.
鉴定出了一个P19胚胎癌细胞系，该细胞系在Pax - 3基因的一个内源性拷贝中插入了大肠杆菌LacZ基因。利用该细胞系对经化学处理（视黄酸和二甲基亚砜）诱导分化后神经外胚层和中胚层谱系中Pax - 3/LacZ融合基因的表达进行了表征，这与之前胚胎中Pax - 3表达定位于背侧神经外胚层有丝分裂活跃细胞和相邻节段性皮肌节一致。在与经化学诱导剂预处理而分化的未标记P19细胞进行的混合实验中，Pax - 3/LacZ标记的干细胞也被用作靶细胞。靶细胞中β - 半乳糖苷酶和神经外胚层标记物的诱导表明：(1) 一些分化的P19细胞衍生物短暂表达内源性Pax - 3和神经外胚层诱导活性；(2) 未分化的靶干细胞即使在存在白血病抑制因子的情况下也对这些活性有反应；(3) 在诱导神经外胚层方面，内源性活性可与视黄酸处理区分开来，且比视黄酸处理更有效。这些观察结果表明，P19胚胎癌细胞为分析哺乳动物中负责神经外胚层诱导的细胞相互作用提供了一个有用的体外系统。
