Direct Reprogramming Into Corneal Epithelial Cells Using a Transcriptional Network Comprising PAX6, OVOL2, and KLF4
Direct Reprogramming Into Corneal Epithelial Cells Using a Transcriptional Network Comprising PAX6, OVOL2, and KLF4
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DOI：
10.1097/ico.0000000000002074
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发表时间：
2019-11-01
期刊：
影响因子：
2.8
通讯作者：
Kinoshita, Shigeru
中科院分区：
文献类型：
--
作者：
Kitazawa, Koji;Hikichi, Takafusa;Kinoshita, Shigeru
在其早期阶段，胚胎极化形成细胞亚群，随后产生特定的器官细胞类型。这些细胞亚群由激活或抑制特定基因的转录因子(TF)定义。尽管一个胚胎包含数千个转录因子，但令人惊讶的是，决定一个特定细胞的命运所需的因子却少之又少。外胚层分为神经外胚层和表面外胚层，后者产生表皮角质形成细胞和角膜上皮细胞。同时，神经外胚层细胞可以生长到眼睛的其他部位，如角膜内皮和视网膜。为了研究转录因子在CEC中的调节作用，我们在人成纤维细胞中过表达了“核心转录因子”(PAX6、Ovol2和KLF4)，并发现这些细胞具有CEC样的性质。Ovol2的过度表达甚至能够直接诱导具有神经外胚层命运的细胞走向表面外胚层命运，被称为“直接重编程”。相反，抑制Ovol2或PAX6的表达可以诱导CECs分别表现出与神经系细胞或表皮角质形成细胞一致的特性。这表明这些核心转录因子可以通过基因的相互调节来维持CEC表型。直接重编程对细胞疗法具有重要意义。与诱导多能干细胞相比，通过直接重编程获得的细胞的潜在好处包括，与将细胞重新编程回到多能状态然后再重新编程到另一种细胞类型相比，它所需的时间更短。进一步了解核心转录因子的相互抑制作用机制可能导致不需要细胞移植的再生医学的替代治疗。
In its early stages, an embryo polarizes to form cell subpopulations that subsequently produce specific organ cell types. These cell subpopulations are defined by transcription factors (TFs) that activate or repress specific genes. Although an embryo comprises thousands of TFs, surprisingly few are needed to determine the fate of a given cell. The ectoderm divides into the neuroectoderm and surface ectoderm, the latter of which gives rise to epidermal keratinocytes and corneal epithelial cells (CECs). Meanwhile, neuroectoderm cells give rise to other parts of the eye such as the corneal endothelium and retina. To investigate the regulatory role of TFs in CECs, we overexpressed the "core TFs" (PAX6, OVOL2, and KLF4) in human fibroblasts and found that the cells adopted a CEC-like quality. OVOL2 overexpression was even able to directly induce cells with a neuroectoderm fate toward a surface ectoderm fate, designated "direct reprogramming." Conversely, suppression of OVOL2 or PAX6 expression induced CECs to show qualities consistent with neural lineage cells or epidermal keratinocytes, respectively. This suggests that these core TFs can maintain the CEC phenotype through reciprocal gene regulation. Direct reprogramming has important implications for cell therapies. The potential benefits of cells derived by direct reprogramming compared with induced pluripotent stem cells include the fact that it requires less time than reprogramming a cell back to the pluripotent state and then to another cell type. Further understanding of the reciprocally repressive mechanism of action for core TFs could lead to alternative treatments for regenerative medicine not requiring cell transplantation.