Injectable Hybrid SMART spheroids to enhance stem cell therapy for CNS injuries

项目摘要 目前用于中枢神经系统（CNS）损伤如脊髓损伤（SCI）的基于干细胞的治疗， 受到干细胞存活率低、整合效率低、神经可塑性丧失的严重阻碍， 植入细胞的不可控制的分化，所有这些都是由高度抑制性和炎症性的细胞因子引起的。 在疾病或损伤部位的微环境。具体地说，损伤部位的胶质增生导致抑制性神经胶质细胞的分泌。 导致轴突再生不良和存活神经元群体发芽的因素， CNS在初始损伤后再生的内在限制。因此，迫切需要有效的 策略，以产生来自患者源性干细胞的功能性神经元的稳健群体， 建立受损的神经回路为此，我们建议整合几个研究领域，包括 纳米技术，生物材料，神经科学和干细胞生物学，以开发一种新的基于纳米的干细胞 细胞组装平台，其允许在干细胞移植期间产生有利的微环境。 移植和控制体内干细胞命运以用于潜在的临床应用。 为了解决与CNS损伤和疾病相关的再生的根本障碍，我们 建议开发可注射的3D混合SMART神经球体，用于增强干细胞治疗和有效 体内SCI治疗。3D-Hybrid SMART神经球体由可生物降解支架组装而成 富含天然神经ECM的纳米材料，以促进神经干细胞（NSC）存活和分化。 SMART神经球状体还允许装载生物活性分子（即，Notch抑制剂），导致 抑制神经抑制信号传导和促进神经干细胞（NSC）存活之间的协同作用， 分化这一新的技术平台将进一步整合到两个临床先进的模型中：i） 并入有小胶质细胞的炎性CNS类器官模型，和ii）脊髓损伤动物模型。这 多学科研究将为神经再生研究和细胞治疗提供下一代平台。 从开发用于增强干细胞的新的3D球体组装方法的角度来看， CNS损伤后抑制性环境的存活和抑制。 我们建议通过解决以下具体问题来验证我们的中心假设并实现我们的目标 目的：目的#1 -开发生物活性和生物降解的基于纳米支架的可注射3D混合SMART 球状体; AIM #2 -研究SMART球状体中的深层药物（Notch-i）递送并研究神经元 神经抑制和免疫微环境下干细胞分化和轴突生长 体外;目的#3 -确定3D混合SMART球状体对调节 神经抑制微环境和增强SCI功能恢复。总的来说， 我们预计，我们提出的研究将提供一种创新的、高效的和稳健的方法， 开发神经系统疾病的治疗干预措施。

PROJECT SUMMARY Current stem cell-based treatments for central nervous system (CNS) injuries such as spinal cord injury (SCI), are severely hampered by poor stem cell survival rates, inefficient integration, loss of neural plasticity, and uncontrollable differentiation of implanted cells, all of which are caused by the highly inhibitory and inflammatory microenvironment at disease or injury sites. Specifically, gliosis at the injury site causes the secretion of inhibitory factors leading to poor axon regeneration and sprouting of surviving neuronal populations, resulting in the intrinsic limitations of the CNS to regenerate after the initial injury. Therefore, there is an urgent need for effective strategies to generate a robust population of functional neurons derived from patient-derived stem cells and re- establish the damaged neural circuitry. To this end, we propose to integrate several fields of research, including nanotechnology, biomaterials, neuroscience, and stem cell biology, to develop a novel nanoscaffold-based stem cell assembly platform that allows for the generation of favorable microenvironments during stem cell implantation and the control of stem cell fate in vivo for potential clinical applications. To address the fundamental impediment of regeneration associated with CNS injuries and diseases, we propose to develop injectable 3D-Hybrid SMART neuro-spheroids for enhanced stem cell therapy and effective treatment of SCI in vivo. The 3D-Hybrid SMART neuro-spheroids are assembled from biodegradable scaffold nanomaterials enriched with natural neural ECM to promote neural stem cell (NSC) survival and differentiation. The SMART neuro-spheroids also permit the loading of a bioactive molecule (i.e., Notch inhibitor), resulting in the synergy between suppressing neuroinhibitory signaling and promoting neural stem cell (NSC) survival and differentiation. This novel technology platform will be further integrated into two clinically advanced models: i) an inflammatory CNS organoid model incorporated with microglia, and ii) a spinal cord injury animal model. This multidisciplinary study will provide a next-generation platform for research and cell therapy in neuro-regenerative medicine from the perspective of developing a new 3D spheroid assembly method for enhanced stem cell survival and suppression of inhibitory environment after CNS injuries. We propose to verify our central hypothesis and achieve our objectives by addressing the following specific aims: AIM #1 – Develop bioactive and biodegradable-nanoscaffold-based injectable 3D-Hybrid SMART spheroids; AIM #2 – Investigate deep drug (Notch-i) delivery in SMART spheroids and study neuronal differentiation of stem cells and axonal growth under neuroinhibitory and immune microenvironments in vitro; AIM #3 – Determine the therapeutic effects of 3D-Hybrid SMART spheroids on the modulation of neuroinhibitory microenvironments and the enhancement of SCI functional recovery in vivo. Collectively, we anticipate that our proposed studies will provide an innovative, highly effective, and robust method for developing therapeutic interventions for neurological disorders.