Advancing the functional maturity of brain organoids by synthetic afferentation.

项目摘要 人类多能干细胞（hiPSC）是理解支配细胞分化的原理的有力工具。 人类大脑的发育和神经系统疾病的建模。一个重要的最近 该技术的应用是产生三维（3D）脑细胞培养物或“类器官”。“大脑 类器官已被证明在结构、转录和功能上具有相似性，直到中晚期。 妊娠人脑与早产人EEG记录和人转录组谱的比较。 目前，它们代表了最接近天然人脑组织的细胞模型。虽然强大的 一个探索产前发育机制的系统试图促进大脑的成熟状态 类器官已被证明是增量的、不确定的或复制性差的。因此，大脑类器官系统 仍然很大程度上不适合用于模拟出生后的大脑。有必要开发一种新的 生成适合于询问后期发育阶段的脑类器官模型。这 该提案侧重于理解生理输入作为更强大的必要驱动力的作用， 在脑类器官中的活动的可再现的和成熟的生理状态。该项目将制定方法， 用于引入发育相关的输入和用于阅读人脑类器官中的神经元活动。 来自其他系统的大量工作已经确定，传入网络活动有助于建立，维持， 并改善活跃的大脑功能回路。在这里，我们将测试一系列创新策略，以取代或模仿 通过长时间的模式化刺激人脑类器官来丢失外部输入。然后我们将观察 从而对网络活性和基因表达产生影响。我们将把这些观察结果与现有数据进行基准比较 来自人类皮质类器官以及人类和啮齿动物大脑的集合。建立的工具和方法 这里的术语“细胞培养模型”旨在容易地适用于神经元输入的其它器官系统的细胞培养模型 都很重要如果成功的话，这个项目将建立一个新的平台， 成熟，并将使进入更先进的阶段，人类大脑的发展和人类 神经和神经精神疾病状态。

PROJECT SUMMARY Human pluripotent stem cells (hiPSCs) are a powerful tool for understanding the principles that govern the development of the human brain and for modeling diseases of the nervous system. One important recent application of this technology is the generation of tri-dimensional (3D) brain cell cultures or "organoids." Brain organoids have been shown to develop structural, transcriptional, and functional similarities up to the mid-to-late gestation human brain as compared to preterm human EEG recordings and human transcriptome profiles. Currently they represent the closest cellular model to native human brain tissue available. While a powerful system for probing mechanisms of prenatal development attempts to advance the maturation state of brain organoids have proved to be incremental, inconclusive, or poorly reproduced. As a result, brain organoid systems remain largely inappropriate for modeling the postnatal brain. There is a significant need to develop a new generation of brain organoid models that are appropriate for interrogating later developmental stages. This proposal focuses on understanding the role of physiological inputs as a necessary driver of more robust, reproducible, and mature physiological states of activity in brain organoids. This project will develop approaches for introducing developmentally-relevant inputs and for reading out neuronal activity in human brain organoids. Extensive work from other systems has established that afferent network activity serves to establish, maintain, and refine active functional brain circuits. Here, we will test a series of innovative strategies to replace or mimic missing external inputs via prolonged patterned stimulation of human brain organoids. We will then observe the resulting effects on network activity and gene expression. We will benchmark these observations to existing data sets from human cortical organoids as well as the human and rodent brain. The tools and approaches established here are intended to be readily adapted to cell culture models of other organ systems for which neuronal inputs are important. If successful, this project will establish a novel platform for interrogating activity-dependent maturation and will enable access to more advanced stages of human brain development and human neurological and neuropsychiatric disease states.