Ribbon-shaped microgels as bioinks for 3D bioprinting of anisotropic tissue structures

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Bioprinting Technology

Background:

• Granular microgels offer advantages as bioinks, but traditional spherical microgels yield isotropic tissues, unlike many native anisotropic tissues.
• Existing research on non-spherical microgels for bioprinting needs bioinks that facilitate cell alignment and tunable niche cues.
• The potential of ribbon-shaped microgels (μRBs) for printing 3D anisotropic tissues remains largely unexplored.

Purpose of the Study:

• To develop tunable stiffness microribbons (μRBs) as anisotropic bioinks for extrusion-based bioprinting.
• To investigate the printability and cell alignment capabilities of μRB bioinks.
• To explore the application of μRB bioinks in modeling complex biological processes like cancer metastasis.

Main Methods:

• Fabrication of microribbons (μRBs) with varying stiffness.
• Extrusion-based bioprinting of μRB bioinks.
• Assessment of μRB printability and in-situ alignment during extrusion.
• Cell culture studies using mesenchymal stromal cells (MSCs) and endothelial cells within μRB bioinks.
• Evaluation of cell alignment, osteogenesis, and cancer cell invasion in 3D μRB constructs.

Main Results:

• μRB bioinks demonstrated excellent printability and alignment during extrusion.
• μRB stiffness positively correlated with MSC and endothelial cell alignment.
• Increased μRB stiffness promoted 3D osteogenesis of MSCs.
• μRB bioinks successfully modeled breast cancer-bone metastasis with spatial patterning of multiple cell types.

Conclusions:

• Ribbon-shaped microgels (μRBs) represent a new class of anisotropic bioinks.
• μRB bioinks offer a versatile platform for creating 3D anisotropic tissues and modeling complex biological systems.
• Tunable stiffness of μRBs allows for control over cell behavior and tissue development in bioprinting applications.