Advances in 3D printed blood-brain barrier models

Area of Science:

• Biotechnology and Biomedical Engineering
• Neuroscience and Pharmacology

Background:

• Blood-Brain Barrier (BBB) integrity is vital for central nervous system (CNS) homeostasis.
• The BBB poses a significant challenge for effective drug delivery to the brain.
• 3D bioprinting provides advanced capabilities for creating intricate neurovascular models.

Purpose of the Study:

• To review recent advancements in 3D bioprinting methodologies for Blood-Brain Barrier (BBB) models.
• To explore composite bioink formulations and their impact on endothelial cell function and barrier properties.
• To discuss emerging strategies and future directions for 3D bioprinted BBB platforms.

Main Methods:

• Utilized extrusion-based coaxial nozzle printing for multilayered capillaries.
• Employed droplet-based drop-on-demand deposition, digital light processing, and two-photon polymerization for high-resolution vascular features.
• Investigated hybrid systems integrating electrospun scaffolds and composite bioinks (natural/synthetic hydrogels).

Main Results:

• 3D printed constructs demonstrated selective molecular permeability and sustained barrier integrity under perfusion.
• Bioprinted models showed improved repeatability compared to conventional static cultures.
• Bioinks promoted endothelial cell viability and tight junction protein expression.

Conclusions:

• 3D bioprinting offers precise control for developing advanced Blood-Brain Barrier (BBB) models.
• These models show promise for CNS drug screening and mechanistic studies.
• Further research is needed to address limitations in resolution, mechanical robustness, and long-term stability.