Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut 06268, USA.
Stem Cells. 2012 Sep;30(9):1852-62. doi: 10.1002/stem.1162.
Human embryonic stem cell-derived neuronal progenitors (hNPs) provide a potential source for cellular replacement following neurodegenerative diseases. One of the greatest challenges for future neuron replacement therapies will be to control extensive cell proliferation and stimulate cell migration of transplanted cells. The doublecortin (DCX) gene encodes the protein DCX, a microtubule-associated protein essential for the migration of neurons in the human brain. In this study, we tested whether increasing the expression of DCX in hNPs would favorably alter their proliferation and migration. Migration and proliferation of hNPs was compared between hNPs expressing a bicistronic DCX/IRES-GFP transgene and those expressing a green fluorescent protein (GFP) transgene introduced by piggyBac-mediated transposition. The DCX-transfected hNPs showed a significant decrease in their proliferation and migrated significantly further on two different substrates, Matrigel and brain slices. Additionally, a dense network of nestin-positive (+) and vimentin+ fibers were found to extend from neurospheres transplanted onto brain slices, and this fiber growth was increased from neurospheres containing DCX-transfected hNPs. In summary, our results show that increased DCX expression inhibits proliferation and promotes migration of hNPs.
人类胚胎干细胞衍生的神经元祖细胞（hNPs）为神经退行性疾病后的细胞替代提供了潜在的来源。未来神经元替代治疗的最大挑战之一将是控制移植细胞的广泛增殖和刺激细胞迁移。双皮质素（DCX）基因编码的蛋白 DCX 是一种微管相关蛋白，对于人类大脑中神经元的迁移至关重要。在这项研究中，我们测试了增加 hNPs 中的 DCX 表达是否会有利地改变其增殖和迁移。通过 piggyBac 介导的转座将双顺反子 DCX/IRES-GFP 转基因和表达绿色荧光蛋白（GFP）转基因引入 hNPs 中，比较 hNPs 的迁移和增殖。转染 DCX 的 hNPs 的增殖显著减少，在两种不同的基质（Matrigel 和脑片）上迁移的距离明显更远。此外，从移植到脑片上的神经球中发现巢蛋白（nestin）阳性（+）和波形蛋白+纤维形成密集的网络，并且来自含有转染 DCX 的 hNPs 的神经球的纤维生长增加。总之，我们的结果表明，增加的 DCX 表达抑制 hNPs 的增殖并促进其迁移。
