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bioRxiv · 10.1101/2024.10.01.615952

A stepwise, modular design of building uniform brain assembloids representing the dynamic cellular interplay between neurons and glial cells

Kim, E.·Kim, Y.·Hong, S.·Kim, I.·Lee, J.·Yoo, J.-Y.·Kim, J.·Yoo, K.·Kim, J.-H.·Choi, J.·Shin, K.
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Abstract

Current brain organoid technology fails to provide adequate patterning cues to induce a mature structure that represent the complexity of the human brain. Here, we developed a module-based cellular reconstitution technology to sequentially build uniform forebrain assembloids with mature cortical structures and functional connectivity. The uniformity and maturity of the newly-conceived forebrain assembloids were achieved by creating single-rosette-based organoids at the early stage, whose sizes were big and consistent with the treatment of Wnt and Hedgehog agonists, followed by spatial reconstitution with the Reelin-expressing neuronal layer and non-neuronal glial cells. The resulting single-rosette-based forebrain assembloids were highly uniform and reproducible without significant batch effects, solving major heterogeneity issues caused by difficulties in controlling the number and size of rosettes in conventional multi-rosette organoids. Furthermore, these forebrain assembloids structurally and functionally recapitulated the physiology of the human brain, including the six-layered cortical structure, functional connectivity, and dynamic cellular interplay between neurons and glial cells. Our study thus provided an innovative preclinical model to study a range of neurological disorders, understanding the pathogenesis of which requires an organoid system capable of representing the dynamic cellular interactions and the maturity of the human brain.

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Kim, E., Kim, Y., Hong, S., Kim, I., Lee, J., Yoo, J.-Y., Kim, J., Yoo, K., Kim, J.-H., Choi, J., Shin, K.. 2024-10-02. A stepwise, modular design of building uniform brain assembloids representing the dynamic cellular interplay between neurons and glial cells. https://doi.org/10.1101/2024.10.01.615952

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