Hyaluronic Acid-Based 3D Bioprinted Hydrogel Structure for Directed Axonal Guidance and Modeling Innervation In Vitro

Area of Science:

• Biomaterials Science
• Neuroscience
• Tissue Engineering

Background:

• Axon guidance is critical for tissue development and function but often neglected in tissue engineering.
• Understanding and directing neuronal connections in engineered tissues remains a challenge.

Purpose of the Study:

• To develop a novel 3D axonal guidance structure using multimaterial 3D bioprinting.
• To investigate the role of mechanical properties and guidance cues in directing neuronal network formation and innervation.

Main Methods:

• Utilized acellular hyaluronic acid-based bioinks with differing stiffness properties.
• Employed multimaterial 3D bioprinting to create alternating, parallel-aligned filaments for axonal guidance.
• Cultured human pluripotent stem cell (hPSC)-derived neurons within the 3D structure to assess network formation and innervation.

Main Results:

• Demonstrated successful 3D multimaterial bioprinting of a stable axonal guidance structure.
• Confirmed that softer passages with guidance cues promoted neuronal network formation and axonal elongation.
• Achieved complete innervation by peripheral neurons within 14 days via the soft passages.

Conclusions:

• The developed 3D bioprinting approach offers a novel platform for studying 3D innervation and axonal dynamics.
• This model provides a stable, long-term system for investigating neural development and function in engineered tissues.
• Highlights the importance of incorporating axonal guidance strategies in tissue engineering for improved functional outcomes.