Generating human neural diversity with a multiplexed morphogen screen in organoids.

Area of Science:

• Neuroscience
• Developmental Biology
• Stem Cell Biology

Background:

• Morphogens are crucial signaling molecules that orchestrate neural development and cellular diversity.
• Current methods for directed neural differentiation in vitro lack systematic approaches, limiting the generation of specific neural cell populations and understanding of regional specification principles.

Approach:

• Developed an arrayed screen of 14 morphogen modulators applied to human neural organoids.
• Cultured organoids for over 70 days and utilized multiplexed RNA sequencing.
• Integrated data with annotated single-cell references of the human fetal brain.

Key Points:

• The screening approach successfully generated significant regional and cell type diversity across the neural axis in vitro.
• Deconvolution of morphogen-cell type relationships revealed design principles for brain region specification, including critical timing and combinatorial effects.
• Specific tuning of GABAergic neural subtype differentiation unexpectedly yielded primate-specific interneurons.

Conclusions:

• This work establishes a platform for an in vitro morphogen atlas of human neural cell differentiation.
• The findings provide insights into human neural development, evolution, and diseases.
• The systematic approach advances the ability to generate diverse neural cell populations for research and therapeutic applications.