FGF2 Boost for Driving Forebrain Organoid Maturation Under Static Conditions

Area of Science:

• Neuroscience
• Developmental Biology
• Stem Cell Biology

Background:

• Forebrain organoids (FOs) model human brain development but suffer from necrosis due to oxygen diffusion limits.
• Existing dynamic culture methods introduce variability and deviate from the brain's natural static environment.

Purpose of the Study:

• To develop a scalable, static culture protocol for generating robust forebrain organoids with improved viability and structural integrity.
• To leverage principles of allometric scaling in brain growth to optimize organoid culture.

Main Methods:

• A static culture protocol was developed using human embryonic stem cells.
• A transient high-dose Fibroblast Growth Factor 2 (FGF2) treatment (100 ng/ml) was applied for 1 day before neural induction.
• Organoid survival, size, weight, and cellular composition were assessed over 60 days in vitro (DIV).

Main Results:

• Early forebrain organoids (500-1000 µm) achieved an 83.33% survival rate at 20 DIV.
• Organoid area and volume increased significantly up to 60 DIV, with maturation indicated by plateauing growth.
• Immunofluorescence confirmed organized ventricle-like structures, neural progenitors (SOX2), mature neurons (TUJ1, MAP2), astrocytes (GFAP), and synaptic networks (SYN1) at 60 DIV.

Conclusions:

• The developed static culture protocol supports robust forebrain organoid generation, enhancing long-term viability and structural integrity.
• This method offers practical improvements for organoid generation within established frameworks, advancing precision medicine.
• The protocol's scalability and adherence to static conditions provide a more reliable model for studying human brain development.