Uncovering the therapeutic potential of adipose tissue derived neural stem cells for Hirschsprung's disease.

项目摘要 我们研究的首要目标是从皮下脂肪组织中开发一种干细胞疗法 (SAT)以取代先天性缺失的肠神经系统（ENS）在先天性巨结肠病（HSCR）。 手术切除受累结肠是目前HSCR唯一可行的治疗方法。这是一个必要 挽救生命的手术;尽管如此，超过50%的患者仍然患有术后并发症，包括 便秘、大便失禁和小肠结肠炎。为了克服这些发病率， 保留直肠及其功能的治疗是必要的。通过以下方式替换缺失的ENS 干细胞疗法被吹捧为实现这一目标的最有希望的治疗策略。我们集团 证明了干细胞治疗的可行性，通过从肠道收获神经干细胞（NSC）， 当移植到具有HSCR的小鼠中时，植入、迁移和分化成神经元网络。为临床 应用中，这将需要手术切除一段肠。以防止不必要的切除 除了外科手术外，NSC的其他来源也是令人感兴趣的。人体脂肪组织含有干细胞库 这些都是容易获得的。这些细胞已经在270多个临床试验中被用于治疗多种疾病 支持有利的患者安全状况。在我们的初步数据中，我们还发现， 来自鼠脂肪沉积物-皮下脂肪组织（SAT）的脂肪束具有内源性的 神经干细胞在神经病治疗中的应用尚不清楚。我们预测SAT可以提供一个有用的 NSC来源治疗HSCR中的结肠无神经节细胞症;然而，SAT-NSC是否可以 在肠道的无神经节细胞（缺乏ENS）环境中经历神经发生，目前没有 纯化和扩增人SAT-NSC的方法。在这项研究的第一个目的，我们将确定是否纯化 来自小鼠的SAT-NSCs能够在无神经节的肠中神经发生。神经节化ENS是 出生后由从外源性神经纤维束迁移到肠道的NSC补充， 响应来自肠道的环境线索分化成肠神经元。我们将讨论是否 当提供来自神经节的信号线索时，SAT-NSC也可以经历肠神经发生， 无神经节肠在体外共培养系统和通过显微外科SAT-NSC植入体内。到 确定如何分离和扩大人类SAT-NSCs，我们将解决知识的缺乏， 这些细胞的起源。为了实现这一点，从人SAT神经纤维束中分离的细胞将被无偏地 通过在干细胞培养程序之前和之后的单核RNA-Seq表征。表达NSC的细胞 标记物将通过荧光激活细胞分选纯化， 在体外培养和离体移植到肠平滑肌中进行评估。的结果予以 研究将建立分离SAT-NSCs的程序，并评估其治疗先天性 HSCR中的神经病变。

PROJECT SUMMARY The overarching objective of our research is to develop a stem cell therapy from subcutaneous fat tissue (SAT) to replace the congenitally absent enteric nervous system (ENS) in Hirschsprung disease (HSCR). Surgical resection of the affected colon is currently the only viable treatment for HSCR. This is a necessary life-saving procedure; albeit, more than 50% of patients still suffer from postoperative complications including constipation, fecal incontinence, and enterocolitis. To overcome these morbidities, investigations into treatments that can preserve the rectum and its functions are warranted. Replacement of the absent ENS via stem cell therapies is touted as the most promising treatment strategy to achieve this goal. Our group has demonstrated the feasibility of stem cell treatments by harvesting neural stem cells (NSCs) from the gut which engraft, migrate and differentiate into neuronal networks when transplanted into mice with HSCR. For clinical application this would require surgical resection of a piece of intestine. To prevent unnecessary resection surgery, other sources of NSCs are of interest. Human fat (adipose) tissue contains a reservoir of stem cells that are readily accessible. These cells have been examined in over 270 clinical trials for numerous diseases that support favourable patient safety profiles. In our preliminary data we have also identified that nerve fiber bundles from murine fat deposits – subcutaneous adipose tissue (SAT) - harbor an endogenous source of NSCs that are unexplored for the treatment of neuropathies. We predict that the SAT could provide a useful source of NSCs to treat colonic aganglionosis in HSCR; however, it remains undetermined if SAT-NSCs can undergo neurogenesis in the aganglionic (absent ENS) environment of the gut and there are currently no methods to purify and expand human SAT-NSCs. In the first aim of this study, we will determine if purified SAT-NSCs from mice are capable of neurogenesis in aganglionic intestine. The ganglionated ENS is supplemented postnatally by NSCs that migrate into the gut from extrinsic nerve fiber bundles and differentiate into enteric neurons in response to environmental cues from the gut. We will address whether SAT-NSCs can also undergo enteric neurogenesis when provided signalling cues from the ganglionic and aganglionic gut in in vitro coculture systems and via microsurgical SAT-NSC implantation in vivo. To determine how to isolate and expand human SAT-NSCs we will address the paucity of knowledge on the origin of these cells. To accomplish this, cells isolated from human SAT nerve fiber bundles will be unbiasedly characterised by single nuclei RNA-Seq before and after stem cell culture procedures. Cells expressing NSC markers will be purified by fluorescence activated cell sorting and their differentiation potential will be assessed in in vitro culture and in ex vivo transplants to the smooth muscle of the gut. The results of these studies will establish procedures to isolate SAT-NSCs and assess their potential to treat the congenital neuropathy in HSCR.