In Vivo Rescue of the Hematopoietic Niche By Pluripotent Stem Cell Complementation of Defective Osteoblast Compartments.
In Vivo Rescue of the Hematopoietic Niche By Pluripotent Stem Cell Complementation of Defective Osteoblast Compartments.
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通过多能干细胞补充有缺陷的成骨细胞来挽救造血生态位。
DOI：
10.1002/stem.2670
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发表时间：
2017-10
期刊：
影响因子：
--
通讯作者：
Wu JY
中科院分区：
文献类型：
--
作者：
Chubb R;Oh J;Riley AK;Kimura T;Wu SM;Wu JY
成骨细胞在支持骨髓造血中起关键作用。多能干细胞（PSC），包括胚胎干（ES）细胞和诱导多能干（iPS）细胞，能够分化为成骨细胞。为了确定干细胞在体内挽救异常骨骼发育和骨髓造血所需的能力，我们采用了骨骼互补模型。缺乏Runx 2（成骨细胞生成的主要转录因子）的小鼠无法形成矿化的骨骼和骨髓。将野生型GFP+ ES和YFP+ iPS细胞引入Runx 2无效胚泡期胚胎中。我们通过整体荧光和组织学分析评估了GFP/YFP+细胞的贡献，发现所得到的嵌合胚胎中PSC的比例与颅骨中的矿化程度直接相关。此外，PSC对长骨的贡献成功地恢复了骨髓造血。我们验证了这一发现在一个单独的模型与白喉毒素A介导的消融肥大软骨细胞和成骨细胞。值得注意的是，嵌合体胚胎含有低至37.5%的野生型PSC，显示出非常正常的骨骼形态，这表明骨骼发生几乎完全挽救。总之，我们证明了PSC在体内的部分贡献足以补充和重建成骨细胞缺陷的骨骼和造血骨髓。进一步研究使用基因修饰的PSC与成骨细胞中的基因功能的条件性丧失将使我们能够解决信号传导介质在体内调节骨形成和造血生态位的特定作用。骨骼互补方法的示意图，以证明多能干细胞可以促进骨髓造血骨的形成。缺乏Runx 2（骨形成的一种重要转录因子）的胚胎不能形成骨。然而，将Runx 2 −/−囊胚与多能干细胞注射导致嵌合胚胎，其中骨来源于多能干细胞，并拯救造血骨髓。
Bone-forming osteoblasts play critical roles in supporting bone marrow hematopoiesis. Pluripotent stem cells (PSCs), including embryonic stem (ES) cells and induced pluripotent stem (iPS) cells, are capable of differentiating into osteoblasts. To determine the capacity of stem cells needed to rescue aberrant skeletal development and bone marrow hematopoiesis in vivo, we employed a skeletal complementation model. Mice deficient in Runx2, a master transcription factor for osteoblastogenesis, fail to form a mineralized skeleton and bone marrow. Wild-type GFP+ ES and YFP+ iPS cells were introduced into Runx2-null blastocyst-stage embryos. We assessed GFP/YFP+ cell contribution by whole-mount fluorescence and histological analysis and found that the proportion of PSCs in the resulting chimeric embryos is directly correlated with the degree of mineralization in the skull. Moreover, PSC contribution to long bones successfully restored bone marrow hematopoiesis. We validated this finding in a separate model with diphtheria toxin A-mediated ablation of hypertrophic chondrocytes and osteoblasts. Remarkably, chimeric embryos harboring as little as 37.5% wild-type PSCs revealed grossly normal skeletal morphology, suggesting a near-complete rescue of skeletogenesis. In summary, we demonstrate that fractional contribution of PSCs in vivo is sufficient to complement and reconstitute an osteoblast-deficient skeleton and hematopoietic marrow. Further investigation using genetically modified PSCs with conditional loss of gene function in osteoblasts will enable us to address the specific roles of signaling mediators to regulate bone formation and hematopoietic niches in vivo. Schematic illustration of the skeletal complementation approach to demonstrate that pluripotent stem cells can contribute to formation of bone with hematopoietic bone marrow. Embryos lacking Runx2, an essential transcription factor for bone formation, cannot form bones. However, injection of Runx2−/− blastocysts with pluripotent stem cells results in chimeric embryos in which bone is derived from pluripotent stem cells, with rescue of the hematopoietic bone marrow.
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影响因子：
20.1
作者：
Kehat, I;Gepstein, A;Gepstein, L
通讯作者：
Gepstein, L
影响因子：
5.2
作者：
Bilousova, Ganna;Jun, Du Hyun;King, Karen B.;De Langhe, Stijn;Chick, Wallace S.;Torchia, Enrique C.;Chow, Kelsey S.;Klemm, Dwight J.;Roop, Dennis R.;Majka, Susan M.
通讯作者：
Majka, Susan M.
影响因子：
64.8
作者：
通讯作者：
--
Osf2/Cbfa1：成骨细胞分化的转录激活因子
影响因子：
64.5
作者：
Ducy, P;Zhang, R;Karsenty, G
通讯作者：
Karsenty, G
影响因子：
7.7
作者：
Assady, S;Maor, G;Tzukerman, M
通讯作者：
Tzukerman, M