Neural Transplantation Model Using Integration Co-Culture Chamber

Regenerative medicine is a promising therapy for injuries and diseases of the central nervous system (CNS). Implantation of stem cell-derived neurons into the recipient tissue is one of the key processes of the therapy. How the implanted cells establish functional connections with the intact neurons, and whether the established connections are maintained stably for a long time, remain unknown. Here, we report a novel co-culture device for visualizing interconnections between primary and differentiated neuronal cultures, and long-term monitoring of neuronal activity. A circular microchamber surrounded by another chamber is aligned on a microelectrode array (MEA). These chambers are interconnected through 36 microtunnels. Stem cell-derived neurons were cultured in the inner circular chamber, and primary neurons taken from mouse cortices were cultured in the surrounding chamber. Neurites outgrew into the microtunnels from both primary and differentiated neurons. Immunofluorescence images indicated that synaptic connections were formed between them. Propagation of electrical activity was observed 6 days after starting co-culture. More than half of the spontaneous activity was initiated from primary neurons, and the probability of activity propagation to the stem cell-derived neurons gradually increased with culture days. These results suggest that our device is feasible for long-term monitoring of the interaction between stem cell-derived cells and the recipient tissue.