Xeno-Free Peptide-Functionalized Hydrogels Support hiPSC Encapsulation and In Situ Differentiation into Structurally...

Area of Science:

• Biomaterials Science
• Stem Cell Biology
• Cardiovascular Research

Background:

• Current methods for human induced pluripotent stem cell (hiPSC)-derived cardiomyocyte (hiPSC-CM) production use 2D cultures, resulting in structurally immature cells.
• This immaturity limits the application of hiPSC-CMs in disease modeling and regenerative medicine.

Purpose of the Study:

• To develop a xeno-free, fully-defined platform for hiPSC expansion and *in situ* cardiac differentiation.
• To investigate the role of cyclic RGD (cRGD) functionalization and alginate gel properties on hiPSC behavior and cardiomyocyte maturation.

Main Methods:

• Encapsulation of hiPSCs in cRGD-functionalized alginate hydrogels with varying ligand densities and alginate molecular weights.
• Assessment of hiPSC survival, pluripotency, and cardiac differentiation efficiency.
• Evaluation of hiPSC-CM structural maturity and contractile function after retrieval and tissue engineering.

Main Results:

• cRGD functionalization was crucial for hiPSC survival and pluripotency, with optimal support at 25 μM ligand density.
• Softer alginate gels promoted enhanced hiPSC expansion and cardiogenesis.
• 3D *in situ* differentiation yielded hiPSC-CMs with significantly improved structural maturity, including increased Desmin expression.
• Cardiomyocytes derived from softer gels formed tissue-engineered myocardium with superior contractile force.

Conclusions:

• The developed defined, tunable alginate platform supports hiPSC expansion and cardiac differentiation *in situ*.
• This platform enables the biomanufacturing of structurally mature hiPSC-CMs with enhanced functional properties.
• The findings highlight the potential of this platform for regenerative medicine and disease modeling applications.