Human Midbrain Organoids Enriched With Dopaminergic Neurons for Long-Term Functional Evaluation

Area of Science:

• Neuroscience
• Developmental Biology
• Regenerative Medicine

Background:

• Human midbrain organoids with dopaminergic (DA) neurons are crucial for Parkinson's disease (PD) research.
• Current methods struggle with generating small, DA neuron-rich organoids and lack long-term functional assessment tools.

Purpose of the Study:

• To develop an improved method for generating small midbrain organoids (<300 μm) enriched with functional DA neurons.
• To establish a comprehensive functional assay system for long-term evaluation of neural networks in these organoids.

Main Methods:

• Combined developmental patterning with mechanical radial cutting to produce small organoids.
• Developed a functional assay system including calcium transient, neurite extension, and multielectrode array (MEA) assays.

Main Results:

• Radial cutting increased the yield of viable organoids and reduced necrotic regions.
• Demonstrated DA neurons within organoids extend projections, respond to dopamine, and form functional neural networks with giant depolarizing potential-like events.

Conclusions:

• The novel approach successfully generates small, functional midbrain organoids suitable for PD modeling.
• The developed assay system allows for robust, long-term functional assessment of neural networks in PD models.