EFFECT OF HYDROGEL ENCAPSULATION ON THE NEURONAL DIFFERENTIATION OF MES CELLS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 胚胎干细胞是一种多能细胞，可以分化为三个主要胚层：内胚层、中胚层和外胚层。已经开发了许多方法来在培养中将ES细胞区分为特定的细胞类型。主要用于ES细胞定向分化的方法依赖于三维ES细胞聚集体的产生，称为类胚体(EBS)。这一过程的一个固有局限性是由于形成空洞或囊状EB而导致ES细胞分化效率低下。这种空化是由EB核心的细胞死亡造成的，这是由于营养物质扩散到胚状体更深的细胞层的减少。我们假设，营养物质扩散和细胞废物分别流入和流出EBS，可能会导致ES细胞分化的高效率。为了验证这一假设，我们将ES细胞包裹在基于海藻酸盐的水凝胶中，并检测了微重力培养8天后神经元分化的效率。我们的结果表明，在细胞聚集之前包裹MES细胞，与正常EBS培养相比，神经元分化效率提高了2倍。在未来的研究中，我们将通过包裹获得的分化细胞种植到适合未来治疗应用的可生物降解支架中。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Embryonic stem (ES) cells are pluripotent cells that can differentiate into all three main germ layers: endoderm, mesoderm, and ectoderm. A number of methods have been developed to differentiate ES cells into specific cell types in culture. The methods that have been primarily employed in the directed differentiation of ES cells rely on the generation of three-dimensional ES cell aggregates called embryoid bodies (EBs). One inherent limitation of this procedure is the low efficiency of ES cell differentiation due to the formation of cavitated or cystic EB. This cavitation is produced by cell death at the EB core due to a decrease in diffusion of nutrients into the deeper cell layers of the embryoids. We hypothesize that an increase in both nutrient diffusion and cellular waste into and out the EBs, respectively, may result in a high efficiency of ES cell differentiation. To test this hypothesis, we have encapsulated the ES cells inalginate-based hydrogels and examined the efficiency of neuronal differentiation after microgravity culture for 8 days. Our results indicate that encapsulation of mES cells prior to cell aggregation resulted in a 2-fold increase in neuronal differentiation efficiency as compared to that obtained from normal EBs culture. For future studies, we will seed the differentiated cells, obtained from encapsulation, into biodegradable scaffolds suitable for future therapeutic applications.