Optical-flow based non-invasive analysis of cardiomyocyte contractility

Area of Science:

• Cardiovascular Biology
• Biophysics
• Stem Cell Research

Background:

• Accurate characterization of cardiomyocyte (heart muscle cell) beat patterns is crucial for quality control of cells for surgical use.
• Phenotypic characterization in disease modeling and toxicity studies relies on understanding cardiomyocyte contractility.

Purpose of the Study:

• To develop a manipulation-free and efficient method for characterizing cardiomyocyte contractile cycles using optical-flow analysis.
• To distinguish active cardiomyocyte contractility from passive tissue deformations.
• To validate a novel convergence measure for assessing cardiomyocyte function.

Main Methods:

• Videomicroscopic recordings of cardiomyocyte cultures were analyzed using optical-flow computational techniques.
• A novel convergence measure was developed and applied to optical flow data.
• Myosin IIa immuno-localization was used for correlation analysis.
• Analysis was performed on maturing, unlabeled induced pluripotent stem cell-derived cardiomyocyte cultures.

Main Results:

• Optical-flow analysis successfully identified distinct contractile centers within cardiomyocyte cultures.
• The method effectively differentiated active cell contractility from passive elastic tissue deformations.
• The proposed convergence measure showed a positive correlation with myosin IIa immuno-localization.
• Contractile waves and their synchronization were resolved in the analyzed cardiomyocyte cultures.

Conclusions:

• Optical-flow based analysis provides an efficient and non-invasive method for characterizing cardiomyocyte beat patterns.
• The developed convergence measure serves as a reliable indicator of cardiomyocyte contractile activity and myosin IIa expression.
• This approach is valuable for quality control, disease modeling, and toxicity studies involving cardiomyocytes.