In vitro-derived medium spiny neurons recapitulate human striatal development and complexity at single-cell...

Area of Science:

• Neuroscience
• Stem Cell Biology
• Developmental Biology

Background:

• Striatal medium spiny neurons (MSNs) are crucial for motor control and are implicated in neurological disorders.
• Existing protocols for generating human pluripotent stem cell (PSC)-derived MSNs are limited and poorly characterized.
• Understanding MSN development is key for developing effective cell-replacement therapies.

Purpose of the Study:

• To develop a robust and reproducible protocol for generating authentic and functional D1- and D2-MSNs from human PSCs.
• To characterize the developmental trajectory of these engineered MSNs and compare them to endogenous fetal cells.
• To identify strategies for enhancing MSN yield for therapeutic applications.

Main Methods:

• Optimization of cell seeding density and morphogen exposure during differentiation.
• Utilizing single-cell RNA sequencing (scRNA-seq) to analyze cell-fate acquisition and gene expression.
• Modulation of the midkine pathway to improve MSN production.

Main Results:

• A reproducible 25-day protocol yielding authentic and functional D1- and D2-MSNs was established.
• scRNA-seq demonstrated that engineered MSNs recapitulate in vivo cell-fate acquisition, gene expression, and signaling pathways.
• Modulating the midkine pathway significantly increased MSN yield.

Conclusions:

• The developed protocol provides a reliable method for generating functional MSNs from human PSCs.
• These findings offer a valuable tool for investigating striatal disease pathogenesis and advancing cell-replacement therapies.
• This protocol holds promise for future therapeutic strategies, particularly for Huntington's disease (HD).