Analyzing the α-Actinin Network in Human iPSC-Derived Cardiomyocytes Using Single Molecule Localization Microscopy

Area of Science:

• Cardiology
• Cell Biology
• Biophysics

Background:

• Maturation of induced pluripotent stem cell (iPSC)-derived cardiomyocytes is essential for regenerative medicine, drug screening, and disease modeling.
• Achieving an adult-like phenotype in iPSC cardiomyocytes, particularly organized sarcomeres for contraction, remains a significant challenge.
• The sarcomere's α-actinin network organization is a key indicator of cardiomyocyte structural maturity.

Purpose of the Study:

• To present a super-resolution microscopy approach for semi-quantitative analysis of the α-actinin network in cardiomyocytes.
• To compare sarcomere length and Z-disc thickness between iPSC-derived cardiomyocytes and neonatal cardiac cells.
• To validate the reliability of imaging conditions for quantitative structural analysis.

Main Methods:

• Utilized photoactivated localization microscopy (PALM) for super-resolution imaging.
• Performed semi-quantitative analysis of the α-actinin network, sarcomere length, and Z-disc thickness.
• Compared structural parameters in iPSC-derived cardiomyocytes versus neonatal cardiac cells.

Main Results:

• The super-resolution method enables quantitative monitoring of cardiac cell structural maturity with high spatial resolution.
• Subtle changes in sarcomere organization can be detected using this approach.
• Demonstrated the critical influence of imaging conditions on data reliability.

Conclusions:

• The developed super-resolution method is suitable for assessing the structural maturity of cardiomyocytes.
• This technique facilitates the quantitative evaluation of sarcomere organization in iPSC-derived cardiomyocytes.
• The findings support the advancement of iPSC cardiomyocyte applications in various biomedical fields.