Exploring the Effect of Three-Dimensional Microenvironment on Human Brain Cortical Development

Brain organoids—tiny, lab-grown models that mimic certain features of the human brain—are an exciting tool for studying these questions. However, creating organoids consistently with similar features has been difficult, often leading to variable results. My research aims to improve the way brain organoids are made, ensuring they are more reliable and effective for research. Thus, in my dissertation research, first, I created a unique culture system using high-resolution 3D-printed microwells. This system produced brain organoids that were more uniform and mature, featuring key structures like inner cavities (lumens), folds, and layered cortical structures. This method provided an alternative to traditional methods that rely on embedding in Matrigel. Next, I addressed the limitations of traditional systems that rely solely on stem cells' natural self-assembly, which limits their shape and control. To overcome this, I developed a new magnetic assembly system. By using magnetic fields in specific shapes (rings, dishes, and squares), I was able to guide how the cells came together and shaped the organoids. The ring magnetic pattern showed the best results, producing organoids with distinct brain regions that closely mimic the human brain's development by day 28. This innovative magnetic approach ensures organoids develop consistently with the right shapes and features, enhancing their reliability for studying brain development and related diseases. Lastly, I developed a method where two organoids are fused together using precisely measured microwell distances (ranging from 850 to 1000 micrometers). The results were intriguing: at 8650 and 900 micrometers, the organoids developed expanded neuroepithelial structures, while at 950 micrometers, they formed more complex, cortex-like structures. This platform also allowed me to model how brain tumors invade healthy brain tissue, providing a detailed view of the tumor spread at the single-cell level.