Three-dimensional bioprinting using self-assembling scalable scaffold-free "tissue strands" as a new bioink

Area of Science:

• Bioprinting and Tissue Engineering
• Biomaterials Science
• Regenerative Medicine

Background:

• Tissue engineering aims to create functional tissues using biomaterials, cells, and signaling molecules.
• Scaffold-free bioprinting mimics embryonic development through self-assembly, offering a promising approach.
• Current limitations include challenges in scaling up bioprinted tissues to clinically relevant sizes and maintaining functionality.

Purpose of the Study:

• To engineer novel scaffold-free, scalable tissue strands as a bioink for robotic-assisted bioprinting.
• To overcome limitations in scale-up and recapitulation of tissue biology and functionality in bioprinted tissues.
• To demonstrate the utility of this approach for creating complex tissues, such as articular cartilage.

Main Methods:

• Fabrication of scaffold-free, solid-form tissue strands as a novel bioink material.
• Utilization of robotic-assisted bioprinting for precise deposition of tissue strands.
• Verification of the method using cartilage strands to bioprint articular cartilage tissue.

Main Results:

• Successfully bioprinted near 8 cm-long scaffold-free tissue strands without requiring scaffolds, molds, or liquid media.
• Demonstrated rapid fusion and self-assembly capabilities of the bioprinted tissue strands.
• Achieved native-like scale-up tissues, overcoming previous roadblocks in tissue engineering.

Conclusions:

• Scaffold-free scalable tissue strands represent a significant advancement in bioink technology for bioprinting.
• This method facilitates the creation of large-scale, functional tissues with improved biological relevance.
• The demonstrated application in articular cartilage highlights the potential for clinical translation in regenerative medicine.