Meyer Jason S, Katz Martin L, Maruniak Joel A, Kirk Mark D
Division of Biological Sciences, 103 Lefevre Hall, University of Missouri, Columbia, MO 65211, USA.
Brain Res. 2004 Jul 16;1014(1-2):131-44. doi: 10.1016/j.brainres.2004.04.019.
Embryonic stem (ES) cells can differentiate into many specialized cell types, including those of the nervous system. We evaluated the differentiation of enhanced green fluorescent protein (EGFP)-expressing B5 mouse ES cells in vitro and in vivo after transplantation into the eyes of mice with hereditary retinal degeneration. After neural induction with retinoic acid, the majority of cells in embryoid bodies expressed markers for neural progenitors as well as for immature and mature neurons and glial cells. When induced ES cells were plated in vitro, further differentiation was observed and the majority of cells expressed beta-III Tubulin, a marker for immature neurons. In addition, many plated cells expressed markers for mature neurons or glial cells. Four days after intravitreal transplantation into the eyes of rd1 mice (a model of rapid retinal degeneration), donor cells appeared attached to the vitreal surface of the retina. After 6 weeks in vivo, most transplanted cells remained adherent to the inner retinal surface, and some donor cells had integrated into the retina. Transplanted cells exhibited some properties typical of neurons, including extensive process outgrowth with numerous varicosities and expression of neuronal and synaptic markers. Therefore, after induction B5 ES cells can acquire the morphologies of neural cells and display markers for neuronal and glial cells in vitro and in vivo. Furthermore, when placed in the proper microenvironment ES-derived neural precursors can associate closely with or migrate into nervous tissue where differentiation appears to be determined by cues provided by the local environment, in this case the degenerating neural retina.
胚胎干细胞（ES细胞）能够分化为多种特化细胞类型，包括神经系统的细胞类型。我们评估了表达增强型绿色荧光蛋白（EGFP）的B5小鼠ES细胞在体外用视黄酸进行神经诱导后，以及在移植到患有遗传性视网膜变性的小鼠眼中后的体内分化情况。在用视黄酸进行神经诱导后，胚状体中的大多数细胞表达神经祖细胞以及未成熟和成熟神经元及神经胶质细胞的标志物。当将诱导后的ES细胞接种到体外时，观察到进一步的分化，大多数细胞表达β-III微管蛋白，这是未成熟神经元的标志物。此外，许多接种的细胞表达成熟神经元或神经胶质细胞的标志物。将其玻璃体内注射到rd1小鼠（快速视网膜变性模型）眼中4天后，供体细胞似乎附着在视网膜的玻璃体表面。在体内6周后，大多数移植细胞仍附着在内视网膜表面，并且一些供体细胞已整合到视网膜中。移植细胞表现出一些典型的神经元特性，包括具有大量曲张的广泛突起生长以及神经元和突触标志物的表达。因此，诱导后的B5 ES细胞能够在体外和体内获得神经细胞的形态，并显示神经元和神经胶质细胞的标志物。此外，当置于适当的微环境中时，ES来源的神经前体细胞可以与神经组织紧密结合或迁移到神经组织中，在这种情况下，分化似乎由局部环境（即退化的神经视网膜）提供的线索决定。
