Bioprinting of Aptamer-Based Programmable Bioinks to Modulate Multiscale Microvascular Morphogenesis in 4D

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Endothelial cell assembly into vascular networks is crucial for tissue development and function.
• Controlling growth factor presentation is key to directing vascular morphogenesis.
• Existing methods lack precise temporal and spatial control over growth factor release.

Purpose of the Study:

• To develop programmable bioinks for dynamic vascular endothelial growth factor (VEGF) presentation.
• To investigate how controlled VEGF release influences vascular network formation in 3D bioprinted constructs.
• To engineer functional, hierarchically self-organized vascular networks within engineered tissues.

Main Methods:

• Development of programmable bioinks utilizing aptamers for VEGF sequestration.
• Employing complementary sequence (CS) hybridization to tune VEGF release kinetics.
• 3D bioprinting of constructs with varying spatial resolutions.
• Analysis of microvascular network alignment, organization, and morphogenesis.

Main Results:

• Programmable bioinks successfully guided vascular morphogenesis through dynamic VEGF presentation.
• CS-triggered VEGF release significantly influenced microvascular network alignment and organization.
• Lower spatial resolution designs enhanced network properties, with CS-treated low-resolution constructs showing increased vessel density, branching, and length.
• Hierarchical network formation was restricted to aptamer regions, demonstrating spatial control.

Conclusions:

• Programmable bioinks offer precise, on-demand control over vascular network formation.
• CS acts as an external trigger for time-controlled remodeling of bioprinted vascular networks.
• This technology holds promise for advancing the bioengineering of complex vascularized tissues.