Connexin 43-Enriched Vesicles Improve Synchronization in hiPSC-Derived Cardiomyocytes

Area of Science:

• Cardiovascular Research
• Stem Cell Biology
• Biotechnology

Background:

• Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) are crucial for studying cardiac cell communication.
• However, hiPSC-CMs exhibit immaturity, leading to poor electrical and mechanical coupling.
• Enhancing gap junction-mediated communication is essential for functional cardiomyocyte networks.

Purpose of the Study:

• To investigate methods for improving intercellular coupling in hiPSC-CMs.
• To develop and characterize Connectosomes, plasma membrane vesicles enriched in functional connexin hemichannels.
• To assess the efficacy of Connectosomes in enhancing cardiomyocyte synchronization and coordination.

Main Methods:

• Development of Connectosomes from plasma membrane vesicles enriched in connexin hemichannels.
• Characterization of Connectosome orientation and connexin-43 (Cx43) expression.
• Mathematical modeling and experimental validation of Connectosome incorporation.
• Assessment of calcium transients and beating coordination in cardiomyocyte networks.

Main Results:

• Connectosomes demonstrated proper orientation of connexins and enriched Cx43 at cardiomyocyte borders.
• Connectosome incorporation reinforced endogenous gap junctions and promoted synchronous calcium transients.
• Improved spatial coordination of beating was observed across cardiomyocyte networks.
• Mechanistic studies confirmed the critical role of connexin channel orientation and functionality.

Conclusions:

• Connectosomes effectively enhance gap junction-mediated communication in immature cardiomyocytes.
• These vesicles synchronize cardiomyocyte beating by boosting electrochemical communication.
• Connectosomes represent a promising strategy for advancing cardiac cell therapy and regenerative medicine.