Micro Three-Dimensional Neuronal Cultures Generate Developing Cortex-Like Activity Patterns

Studies aimed at neurological drug discovery have been carried out bothin vitroandin vivo.In vitrocell culture models have showed potential as drug testing platforms characterized by high throughput, low cost, good reproducibility and ease of handling and observation. However,in vitroneuronal culture models are facing challenges in replicatingin vivo-like activity patterns. This work reports anin vitroculture technique that is capable of producing micro three-dimensional (mu 3D) cultures of only a few tens of neurons. The mu 3D cultures generated by this method were uniform in size and density of neurons. These mu 3D cultures had complex spontaneous synchronized neuronal activity patterns which were similar to those observed in the developing cortex and in much larger 3D cultures, but not in 2D cultures. Bursts could be reliably evoked by stimulation of single neurons. Synchronized bursts in mu 3D cultures were abolished by inhibitors of glutamate receptors, while inhibitors of GABA(A)receptors had a more complex effect. This pharmacological profile is similar to bursts in neonatal cortex. Since large numbers of reproducible mu 3D cultures can be created and observed in parallel, this model of the developing cortex may find applications in high-throughput drug discovery experiments.