Novel magnetic core/shell nanoparticle-based stem cell therapy to direct neural s

描述：这一应用的长期目标是开发新型磁性核/壳纳米颗粒(MCNPs)，以输送并在时空上触发干细胞向少突胶质细胞的分化。在脊髓损伤方面，神经干细胞/祖细胞移植已被证明具有许多良好的治疗效果。然而，移植的NSPC被发现主要分化为星形胶质细胞，这往往阻碍移植的有效性。移植的NSPC定向分化为少突胶质细胞是非常可取的，因为这些细胞在轴突周围提供髓鞘，从而使神经冲动在中枢神经系统快速传播。为此，我们的目标是开发新型的MCNPs，它具有在热休克启动子的作用下传递编码寡核苷酸的质粒和通过磁热(即使用交变磁场)触发寡核苷酸表达的双重功能。先前报道的寡核苷酸可以在热休克启动子下诱导NSPC向少突胶质细胞分化。为了应对这些挑战，提出了以下具体目标：具体目标1.制备磁性核/壳纳米粒子和可诱导的基因载体，用于将其导入人诱导雨生干细胞来源的神经干细胞/祖细胞(hiPSC来源的神经干细胞/祖细胞)。具体目的2.检测体外培养的工程化NSPC在磁热诱导基因表达后的少突胶质细胞分化和再髓鞘形成能力。磁性纳米颗粒此前已被应用于磁共振成像、细胞靶向和药物/基因输送。然而，现有的知识和这些纳米颗粒在干细胞治疗中的临床应用之间存在着严重的差距。因此，基于MCNP的新型干细胞疗法的发展将展示MNPs用于临床相关脊髓损伤治疗的多功能性质。特别是，与传统的基因疗法和细胞标记方法相比，基于MCNP的方法将提供许多优势，包括：i)非侵入性磁共振成像(由于磁核)和拉曼成像(由于金壳)能力，ii)磁场促进的基因载体进入干细胞的输送(‘磁融合’)，以及iii)磁热疗法，这将被用来为所传递的基因的激活提供一种机制。总体而言，建议的MCNP方法将把一种方法学带入前沿，允许用户实现对细胞分化的空间和时间控制，同时潜在地保持干细胞/前体细胞固有的神经保护特性。就这样， 科学家和临床医生可以利用干细胞的全部潜力(即固有的治疗特性和受控的细胞命运规范)来加强脊髓损伤的治疗。

DESCRIPTION: The long-term goal of this application represents the development of novel magnetic core/shell nanoparticles (MCNPs) to deliver and spatiotemporally trigger the differentiation of stem cells to oligodendrocytes. With regard to spinal cord injury, neural stem/progenitor cell (NSPCs) transplantation has been shown to afford a number of favorable therapeutic effects. However, grafted NSPCs were found to differentiate primarily into astrocytes, which tend to hinder the effectiveness of transplantation. The guided differentiation of the grafted NSPCs into oligodendrocytes is highly desirable since these cells provide myelin sheaths around axons and thus enable fast propagation of nerve impulses in the CNS. To this end, the objective is to develop novel MCNPs, which have the dual functions of delivering a plasmid encoding Olig2, which has previously been reported to induce NSPC differentiation to oligodendrocytes, under a heat shock promoter and triggering Olig2 expression through magnetic hyperthermia (i.e. using an alternating magnetic field). To address these challenges, the following specific aims are proposed: Specific Aim 1. To prepare magnetic core/shell nanoparticles and inducible gene vectors for delivery into human induced pluirpotent stem cell-derived neural stem/progenitor cells (hiPSC-derived NSPCs). Specific Aim 2. To test the oligodendrocyte differentiation and remyelination ability of the engineered NSPCs in vitro after magnetic hyperthermia-induced gene expression. Magnetic nanoparticles have previously been applied for MRI, cell targeting, and drug/gene delivery. However, there is a critical gap between the existing knowledge and the clinical application of these nanoparticles to stem cell-based therapy. Therefore, the development of a novel MCNP-based stem cell therapy will demonstrate the multifunctional nature of MNPs for a clinically-relevant SCI treatment. In particular, compared to conventional gene therapies and cellular labeling methodologies, a MCNP-based approach would offer many advantages including: i) non-invasive magnetic resonance imaging (due to magnetic core) and Raman imaging (due to the gold shell) capabilities, ii) magnetic field-facilitated delivery ('magnetofection') of gene vectors into the stem cells, and iii) magnetic hyperthermia, which will be used to provide a mechanism for the activation of the delivered gene. Overall, the proposed MCNP approach will bring a methodology to the forefront that can allow the user to achieve spatial and temporal control over cellular differentiation, while potentially maintaining the neuroprotective properties innate to stem/precursor cells. In this way, scientists and clinicians can harness the full potential of stem cells (i.e. intrinsic therapeutic properties and controlled cell fate specification) for an enhanced SCI treatment.