Induced Expression of Endogenous CXCR4 in iPSCs by Targeted CpG Demethylation Enhances Cell Migration Toward the Ligand CXCL12
Induced Expression of Endogenous CXCR4 in iPSCs by Targeted CpG Demethylation Enhances Cell Migration Toward the Ligand CXCL12
复制标题
通过靶向 CpG 去甲基化诱导 iPSC 中内源 CXCR4 的表达增强细胞向配体 CXCL12 的迁移
DOI：
10.1007/s10753-018-0869-5
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发表时间：
2019-02-01
期刊：
影响因子：
5.1
通讯作者：
Feng, Ying-Hong
中科院分区：
文献类型：
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作者：
Jiang, Can;Guo, Jun;Feng, Ying-Hong
摘要移植后细胞归巢不良是心脏细胞治疗中尚未解决的常见问题。为了增强干细胞归巢，配体CXC基序趋化因子12（CXCL 12）及其特异性受体CXC受体4型（CXCR 4）在本研究中被用作一个系统，以显示在小鼠诱导的多能干细胞（iPSC）中内源性CXCR 4基因的诱导表达改善了细胞迁移。以小鼠iPSC的CXCR 4启动子区的CpG去甲基化形式的位点特异性表观基因组编辑用CXCR 4 b-TAL-Tetlc完成，CXCR 4 b-TAL-Tetlc是10 - 11易位1（TET 1）的催化结构域与预先设计的合成转录激活因子样效应物（TALE）的DNA结合结构域的C末端的嵌合融合蛋白，其识别小鼠CXCR 4启动子区内的特异性DNA序列。用慢病毒颗粒形式的工程化CXCR 4 b-TAL-Tet 1c感染小鼠iPSC诱导了小鼠iPSC中位点特异性CpG去甲基化和随后的CXCR 4表达激活。正如预期的那样，CXCR 4过表达的iPSC表现出比对照iPSC大3.9倍的迁移，而没有显著改变AKT的干性和活化磷酸化。这些结果为在急性心肌梗死和心力衰竭的啮齿动物模型中进行体内iPSCs移植研究奠定了良好的基础。我们发现，TALE可以通过CpG甲基化增强CXCR 4的表达，并可能保留干性。由CXCL 12激活的iPSC的迁移与AKT的显著磷酸化相关，而不是ERK 12。
AbstractPoor homing of cells after transplantation is an unresolved common issue in cardiac cell therapies. To enhance stem cell homing, the ligand CXC motif chemokine 12 (CXCL12) and its specific receptor CXC receptor type 4 (CXCR4) have been employed as a system in this study to show that induced expression of the endogenous CXCR4 gene in mouse-induced pluripotent stem cells (iPSCs) improved the cell migration. Loci-specific epigenome editing in the form of CpG demethylation at CXCR4 promoter region of the mouse iPSCs was accomplished with CXCR4b-TAL-Tet1c, chimeric fusion proteins of the catalytic domain of ten-eleven translocation 1 (TET1) to the C-terminal end of the DNA binding domains of predesigned synthetic transcription activator-like effectors (TALEs) that recognize specific DNA sequences within the mouse CXCR4 promoter region. Infection of the mouse iPSCs with the engineered CXCR4b-TAL-Tet1c in the form of lentiviral particles induced the loci-specific CpG demethylation and subsequent activation of CXCR4 expression in mouse iPSCs. As expected, the CXCR4-overexpressing iPSCs exhibited 3.9-fold greater migration than the control iPSCs did without alteration of the stemness and activated phosphorylation of AKT significantly. These results set a sound foundation for subsequentin vivoiPSCs transplantation studies in rodent models of acute myocardial infarction and heart failure. We show that TALEs can enhance the expression of CXCR4 by CpG methylation, and may retain the stemness. Migration of iPSCs activated by CXCL12 is associated with significant phosphorylation of AKT, not ERK1/2.