The establishment of novel hair follicle development and hair loss model by inducing iPS cells differentiation and aggregation to form a 3D organoid

本课题旨在通过诱导iPS细胞分化形成体外三维毛囊组织模型来研究毛发的生长和脱失。第一年，我们在实验室成功地建立了iPS培养体系，并在10代培养后保持了多向分化的能力。从第二年开始，我们首先诱导iPS细胞分化为与毛囊相关的特定细胞：角质形成细胞、成纤维细胞和毛乳头。接下来，我们制备了U形96孔板来诱导iPS细胞形成球体。不幸的是，与我们的预期相反，我们发现iPS细胞并不像其他细胞那样自发聚集在一起形成球体。因此，我们决定使用Matrigel Matrix，这是一种已被许多研究使用的细胞外基质，以帮助细胞形成有机体。将iPS细胞与Matrigel混合后，随机固定细胞。培养3d后，可见细胞器的形成，5d时细胞明显增大。加入生长因子后，细胞分化的形态也发生了变化。这些结果表明，Matrigel Matrix可以提供合适的3D环境，帮助细胞形成类似于真实组织的结构，并可用于细胞分化。遗憾的是，由于位置改变，研究人员无法完成进一步的实验。同时，这些结果也为今后研究组织发生和细胞分化的机制提供了有价值的信息和新的方法。

In this project, we aim to investigate the hair growth and loss by inducing iPS cell differentiation to form a 3D hair follicle tissue model in vitro.In the first year, we successfully established the iPS culture system in our lab and maintained the ability of pluripotent differentiation after 10 passages of culture. From the second year, we firstly induced iPS cells differentiation into specific cells associated with hair follicles: keratinocytes, fibroblasts, and dermal papilla. Next, we prepared U-shaped 96-well dishes to induce iPS cells forming spheroids. Unfortunately, contrary to our expectations, we found that iPS cells didn't spontaneously aggregate together to form spheroids like other cells.Therefore, we decided to use Matrigel Matrix, an extracellular matrix that has been used in many studies to assist in cell formation of organoids. After mixing iPS cells with Matrigel, the cells were randomly immobilized. After 3 days with culture medium, the formation of organoids was evident, and a significant enlargement was observed at day 5. Morphological changes in cell differentiation were also observed after the addition of growth factors. These results suggest that Matrigel Matrix can provide a suitable 3D environment to help cells form structures similar to real tissues and can be used for cell differentiation.Unfortunately the investigator is unable to complete the further experiments due to a position change. While, these results still provide valuable information and novel method to study the mechanisms of histogenesis and cell differentiation in the future.