Microdevice for directional axodendritic connectivity between micro 3D neuronal cultures.

Area of Science:

• Neuroscience
• Biomaterials Engineering
• Cell Biology

Background:

• Conventional neuronal cultures lack directional connectivity, limiting accurate in vitro modeling of cortical development and neurological disorders.
• Replicating the directional nature of cortical circuits is essential for understanding brain function and disease.

Purpose of the Study:

• To develop a novel polydimethylsiloxane (PDMS)-based device enabling directional connectivity between micro three-dimensional (μ3D) neuronal cultures.
• To create a more accurate in vitro model for studying cortical development and the pathogenesis of neurological and psychiatric disorders.

Main Methods:

• Fabrication of a PDMS device with through-holes for μ3D cortical cell clusters and microtrenches for axon and dendrite guidance.
• Utilizing axonal edge guidance and novel dendrite targeting concepts within the microtrenches.
• Morphological and functional verification of directional connections and synaptic properties.

Main Results:

• Demonstrated successful directional connectivity between μ3D cortical cell cultures using the PDMS device.
• Confirmed guidance of axons for "en passant" synapses and preservation of directional selectivity.
• Verified that the established connections were glutamatergic.

Conclusions:

• The developed PDMS device successfully establishes directional neuronal connectivity in vitro.
• This technology offers a significant advancement for reconstructing complex cortical circuits and modeling neurological conditions.
• The device serves as a foundational building block for future in vitro neuroscience research.