Sinoatrial node cardiomyocytes derived from human pluripotent cells function as a biological pacemaker.

Area of Science:

• Cardiology
• Stem Cell Biology
• Developmental Biology

Background:

• The sinoatrial node (SAN) is the heart's primary pacemaker, regulating heart rate.
• SAN dysfunction leads to bradycardia and inefficient circulation, often requiring electronic pacemakers.
• Generating functional pacemaker cells in vitro could enable biological pacemaker therapies.

Purpose of the Study:

• To develop a method for generating sinoatrial node-like pacemaker cells (SANLPCs) from human pluripotent stem cells.
• To characterize the functional properties of these generated SANLPCs.
• To assess the potential of SANLPCs as a biological pacemaker therapy.

Main Methods:

• Utilized a transgene-independent method involving stage-specific manipulation of developmental signaling pathways.
• Generated SANLPCs from human pluripotent stem cells.
• Characterized SANLPCs by identifying NKX2-5-negative cardiomyocytes expressing SAN lineage markers and analyzing their electrophysiological properties.

Main Results:

• Successfully generated SANLPCs exhibiting typical pacemaker action potentials, ion current profiles, and chronotropic responses.
• Transplanted SANLPCs demonstrated the ability to pace host rat heart tissue after transplantation into the cardiac apex.
• The generated cells showed characteristics of functional pacemaker cells.

Conclusions:

• A transgene-independent method can generate functional SANLPCs from human pluripotent stem cells.
• These SANLPCs possess key electrophysiological properties of native pacemaker cells.
• Transplanted SANLPCs can function as a biological pacemaker, showing promise for treating SAN dysfunction.