Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan.
PLoS One. 2011;6(7):e21780. doi: 10.1371/journal.pone.0021780. Epub 2011 Jul 7.
The establishment of methods for directive differentiation from human embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) is important for regenerative medicine. Although Sry-related HMG box 17 (SOX17) overexpression in ESCs leads to differentiation of either extraembryonic or definitive endoderm cells, respectively, the mechanism of these distinct results remains unknown. Therefore, we utilized a transient adenovirus vector-mediated overexpression system to mimic the SOX17 expression pattern of embryogenesis. The number of alpha-fetoprotein-positive extraembryonic endoderm (ExEn) cells was increased by transient SOX17 transduction in human ESC- and iPSC-derived primitive endoderm cells. In contrast, the number of hematopoietically expressed homeobox (HEX)-positive definitive endoderm (DE) cells, which correspond to the anterior DE in vivo, was increased by transient adenovirus vector-mediated SOX17 expression in human ESC- and iPSC-derived mesendoderm cells. Moreover, hepatocyte-like cells were efficiently generated by sequential transduction of SOX17 and HEX. Our findings show that a stage-specific transduction of SOX17 in the primitive endoderm or mesendoderm promotes directive ExEn or DE differentiation by SOX17 transduction, respectively.
从人类胚胎干细胞（ESC）和诱导多能干细胞（iPSC）中定向分化的方法的建立对于再生医学很重要。尽管在 ESC 中过表达性相关高迁移率族蛋白 17（SOX17）分别导致胚外或确定内胚层细胞的分化，但其这些不同结果的机制仍不清楚。因此，我们利用瞬时腺病毒载体介导的过表达系统来模拟胚胎发生过程中的 SOX17 表达模式。瞬时转导 SOX17 可增加人 ESC 和 iPSC 来源的原始内胚层细胞中α-胎蛋白阳性胚外内胚层（ExEn）细胞的数量。相比之下，瞬时腺病毒载体介导的 SOX17 表达在人 ESC 和 iPSC 来源的中内胚层细胞中增加了造血表达同源盒（HEX）阳性确定内胚层（DE）细胞的数量，其对应于体内的前 DE。此外，通过 SOX17 和 HEX 的顺序转导可以有效地生成肝样细胞。我们的研究结果表明，在原始内胚层或中内胚层中特异性瞬时转导 SOX17 分别通过 SOX17 转导促进定向 ExEn 或 DE 分化。
