Pan Baohan, Ao Hushan, Liu Su, Xu Yuming, McDonald John W, Belegu Visar
International Center for Spinal Cord Injury, Hugo W. Moser Research Institute at Kennedy Krieger Inc, Baltimore, MD, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Center for the Study of Nervous System Injury and the Restorative Treatment and Research Center, Washington University School of Medicine, St. Louis, MO 63108, USA.
Stem Cell Res. 2018 Dec;33:156-165. doi: 10.1016/j.scr.2018.09.001. Epub 2018 Sep 6.
A platform for studying spinal cord organogenesis in vivo where embryonic stem cell (ESC)-derived neural progenitor cells (NPC) self-organize into spinal cord-like tissue after transplantation in subarachnoid space of the spinal cord has been described. We advance the applicability of this platform by imaging in vivo the formed graft through T2w magnetic resonance imaging (MRI). Furthermore, we used diffusion tensor imaging (DTI) to verify the stereotypical organization of the graft showing that it mimics the host spinal cord. Within the graft white matter (WM) we identified astrocytes that form glial limitans, myelinating oligodendrocytes, and myelinated axons with paranodes. Within the graft grey matter (GM) we identified cholinergic, glutamatergic, serotonergic and dopaminergic neurons. Furthermore, we demonstrate the presence of ESC-derived complex vasculature that includes the presence of blood brain barrier. In addition to the formation of mature spinal cord tissue, we describe factors that drive this process. Specifically, we identify Flk1 cells as necessary for spinal cord formation, and synaptic connectivity with the host spinal cord and formation of host-graft chimeric vasculature as contributing factors. This model can be used to study spinal cord organogenesis, and as an in vivo drug discovery platform for screening potential therapeutic compounds and their toxicity.
已描述了一个用于在体内研究脊髓器官发生的平台，其中胚胎干细胞（ESC）衍生的神经祖细胞（NPC）在移植到脊髓蛛网膜下腔后会自组织形成脊髓样组织。我们通过T2加权磁共振成像（MRI）对形成的移植物进行体内成像，提高了该平台的适用性。此外，我们使用扩散张量成像（DTI）来验证移植物的典型组织结构，表明其模仿了宿主脊髓。在移植物白质（WM）中，我们鉴定出形成胶质界膜的星形胶质细胞、有髓鞘的少突胶质细胞和具有结间体的有髓轴突。在移植物灰质（GM）中，我们鉴定出胆碱能、谷氨酸能、血清素能和多巴胺能神经元。此外，我们证明了ESC衍生的复杂脉管系统的存在，包括血脑屏障的存在。除了成熟脊髓组织的形成，我们还描述了驱动这一过程的因素。具体而言，我们确定Flk1细胞是脊髓形成所必需的，与宿主脊髓的突触连接以及宿主-移植物嵌合脉管系统的形成是促成因素。该模型可用于研究脊髓器官发生，并作为体内药物发现平台，用于筛选潜在的治疗化合物及其毒性。
