Enhanced Human-Induced Pluripotent Stem Cell Derived Cardiomyocyte Maturation Using a Dual Microgradient Substrate.

Area of Science:

• Biomedical Engineering
• Stem Cell Biology
• Cardiovascular Research

Background:

• Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) are valuable for cardiac research but possess an immature phenotype.
• Immature hiPSC-CM characteristics can affect experimental outcomes and limit their utility.

Purpose of the Study:

• To investigate the impact of topographical gradient substrates on hiPSC-CM morphology and function.
• To determine if specific microgroove dimensions can promote hiPSC-CM maturation.

Main Methods:

• Commercially available hiPSC-CM were cultured on substrates with varying microgroove dimensions (8-100 μm width, ~5 nm-1 μm depth).
• Cellular morphology (eccentricity, elongation, orientation) and function (sarcomere length, contractility) were assessed at days 4 and 10.
• Comparisons were made between cells on gradient substrates and a control flat substrate.

Main Results:

• The deepest and widest microgroove regions (8-30 μm width, 0.85-1 μm depth) significantly increased hiPSC-CM eccentricity, elongation, and orientation compared to the control.
• hiPSC-CM on these gradient regions exhibited a prolonged relaxation phase during contraction (400 ms vs. 200 ms).

Conclusions:

• Dual microgradient substrates can effectively influence hiPSC-CM morphology and function.
• These findings suggest that specific topographical cues can stimulate hiPSC-CM migration and maturation, advancing cardiac research applications.