Programming Cellular Alignment in Engineered Cardiac Tissue via Bioprinting Anisotropic Organ Building Blocks

Area of Science:

• Biomedical Engineering
• Regenerative Medicine
• Cardiovascular Research

Background:

• Replicating the complex 3D myocardial architecture of human hearts remains a significant challenge in cardiac tissue engineering.
• Existing methods often struggle to achieve the necessary cellular alignment and functional performance for viable cardiac constructs.

Purpose of the Study:

• To develop a bioprinting strategy for fabricating aligned cardiac tissues using anisotropic organ building blocks (aOBBs).
• To create functional cardiac tissue constructs with controlled cellular organization and enhanced contractile properties.

Main Methods:

• Generation of a bioink from contractile cardiac aOBBs derived from human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs).
• Bioprinting of aligned cardiac tissue sheets with various patterns (linear, spiral, chevron) and aligned cardiac macrofilaments.
• Assessment of contractile force and conduction velocity of the printed cardiac tissues over time.

Main Results:

• Successfully fabricated aligned cardiac tissue sheets and macrofilaments with controlled cellular organization.
• Printed cardiac macrofilaments demonstrated increasing contractile force and conduction velocity over time, outperforming spheroid-based tissues.
• Achieved spatial control over the magnitude and direction of contractile force by manipulating aOBB alignment.

Conclusions:

• Bioprinting aOBBs offers a novel approach to engineer functional cardiac tissues with high cell density and complex cellular alignment.
• This technique provides a platform for creating patient-specific cardiac tissues for disease modeling and therapeutic applications.
• Opens new avenues for developing advanced cardiac constructs that better mimic native myocardial architecture and function.