Zeng Jiahui, Yi Danying, Sun Wencui, Liu Yuanlin, Chang Jing, Zhu Lijiao, Zhang Yonggang, Pan Xu, Dong Yong, Zhou Ya, Lai Mowen, Bian Guohui, Zhou Qiongxiu, Liu Jiaxin, Chen Bo, Ma Feng
Chinese Academy of Medical Sciences & Peking Union Medical College (CAMS & PUMC), Institute of Blood Transfusion, No. 26, Huacai Road, Longtan Industry Park, Chenghua District, Chengdu, 610052, China.
State Key Laboratory of Biotherapy, Sichuan University, Chengdu, 610065, China.
Cell Regen. 2021 Jan 11;10(1):9. doi: 10.1186/s13619-020-00066-0.
The HOX genes are master regulators of embryogenesis that are also involved in hematopoiesis. HOXA9 belongs to a cluster of HOX genes that play extensively studied roles in hematopoiesis and leukemogenesis.
We established HOXA9-inducible human embryonic stem cells (HOXA9/hESCs) with normal pluripotency and potential for hematopoiesis, which could be used to analyze gene function with high accuracy. HOXA9/hESCs co-cultured with aorta-gonad-mesonephros-derived stromal cells (AGM-S3) were induced to overexpress HOXA9 with doxycycline (DOX) at various times after hematopoiesis started and then subjected to flow cytometry.
Induction of HOXA9 from Day 4 (D4) or later notably promoted hematopoiesis and also increased the production of CD34+ cells and derived populations. The potential for myelogenesis was significantly elevated while the potential for erythrogenesis was significantly reduced. At D14, a significant promotion of S phase was observed in green fluorescent protein positive (GFP+) cells overexpressing HOXA9. NF-κB signaling was also up-regulated at D14 following induction of HOXA9 on D4. All of these effects could be counteracted by addition of an NF-κB inhibitor or siRNA against NFKB1 along with DOX.
Overexpression of HOXA9 starting at D4 or later during hematopoiesis significantly promoted hematopoiesis and the production of myeloid progenitors while reduced the production of erythroid progenitors, indicating that HOXA9 plays a key role in hematopoiesis and differentiation of hematopoietic lineages.
HOX基因是胚胎发育的主要调节因子，也参与造血过程。HOXA9属于HOX基因簇，在造血和白血病发生中发挥着广泛研究的作用。
我们建立了具有正常多能性和造血潜能的HOXA9诱导型人胚胎干细胞（HOXA9/hESCs），可用于高精度分析基因功能。将HOXA9/hESCs与主动脉-性腺-中肾来源的基质细胞（AGM-S3）共培养，在造血开始后的不同时间用强力霉素（DOX）诱导HOXA9过表达，然后进行流式细胞术检测。
从第4天（D4）或之后诱导HOXA9显著促进造血，并增加CD34+细胞及其衍生群体的产生。髓系生成潜能显著升高，而红系生成潜能显著降低。在D14时，过表达HOXA9的绿色荧光蛋白阳性（GFP+）细胞中观察到S期显著促进。在D4诱导HOXA9后，D14时NF-κB信号也上调。所有这些效应都可以通过添加NF-κB抑制剂或针对NFKB1的小干扰RNA（siRNA）以及DOX来抵消。
在造血过程中从D4或之后开始过表达HOXA9显著促进造血和髓系祖细胞的产生，同时减少红系祖细胞的产生，表明HOXA9在造血和造血谱系分化中起关键作用。
