REFRESH-Reversible Embedded Bioprinting for Faster Reinforcement and Structuring of dECM Hydrogels.

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Decellularized extracellular matrix (dECM)-based hydrogel inks face limitations in mechanical fragility and slow gelation, hindering complex tissue fabrication.
• Existing bioprinting methods struggle with structural fidelity due to these biomaterial constraints.

Purpose of the Study:

• To introduce REFRESH (Reversible Embedded Bioprinting for Faster Reinforcement and Structuring of dECM Hydrogels), a next-generation embedded bioprinting platform.
• To enhance the fabrication of high-fidelity, anatomically relevant tissue constructs using dECM hydrogels.

Main Methods:

• Developed a custom polyethylene glycol (PEG)-gelatin microgel suspension bath to modulate rheological properties and promote in situ dECM hydrogel gelation.
• Utilized hydrogen bonding and crowding-induced interactions for enhanced filament stabilization and reduced structural fusion.
• Co-printed cartilage and trachealis muscle-derived dECM for tracheal architecture and lung-derived dECM for bronchial structures.

Main Results:

• The REFRESH platform demonstrated improved print fidelity and faster stabilization compared to conventional thermal gelation.
• Successfully recreated the zonal architecture of the trachea and fabricated functional trifurcated bronchial structures.
• Validated the platform's versatility by printing diverse tissue-specific dECM hydrogels.

Conclusions:

• REFRESH significantly advances the capabilities of dECM-based bioprinting for creating complex, functional tissue constructs.
• The platform enables precise fabrication of anatomically relevant tissues, including airway structures, with improved structural integrity.
• REFRESH offers a versatile solution for tissue engineering applications beyond the airway system.