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Updated: Dec 9, 2025
Generation and Expansion of Human Cardiomyocytes from Patient Peripheral Blood Mononuclear Cells
Published on: February 12, 2021
LRP2 controls sonic hedgehog-dependent differentiation of cardiac progenitor cells during outflow tract formation
Annabel Christ1, Maike Marczenke1, Thomas E Willnow1
1Max-Delbrueck-Center for Molecular Medicine, 13125 Berlin, Germany.
Abstract:
Conotruncal malformations are a major cause of congenital heart defects in newborn infants. Recently, genetic screens in humans and in mouse models have identified mutations in LRP2, a multi-ligand receptor, as a novel cause of a common arterial trunk, a severe form of outflow tract (OFT) defect. Yet, the underlying mechanism why the morphogen receptor LRP2 is essential for OFT development remained unexplained. Studying LRP2-deficient mouse models, we now show that LRP2 is expressed in the cardiac progenitor niche of the anterior second heart field (SHF) that contributes to the elongation of the OFT during separation into aorta and pulmonary trunk. Loss of LRP2 in mutant mice results in the depletion of a pool of sonic hedgehog-dependent progenitor cells in the anterior SHF due to premature differentiation into cardiomyocytes as they migrate into the OFT myocardium. Depletion of this cardiac progenitor cell pool results in aberrant shortening of the OFT, the likely cause of CAT formation in affected mice. Our findings identified the molecular mechanism whereby LRP2 controls the maintenance of progenitor cell fate in the anterior SHF essential for OFT separation, and why receptor dysfunction is a novel cause of conotruncal malformation.
Insights
Mutations in LRP2 disrupt cardiac progenitor cell maintenance, leading to outflow tract defects like common arterial trunk. This research uncovers LRP2's role in preventing congenital heart malformations.
Area of Science:
- Developmental Biology
- Cardiovascular Research
- Genetics
Background:
- Conotruncal malformations are a significant cause of congenital heart defects.
- Mutations in LRP2, a multi-ligand receptor, have been linked to common arterial trunk (CAT), a severe outflow tract (OFT) defect.
- The precise mechanism by which LRP2 influences OFT development was previously unknown.
Purpose of the Study:
- To elucidate the molecular mechanism by which LRP2 is essential for OFT development.
- To investigate the role of LRP2 in maintaining cardiac progenitor cells in the anterior second heart field (SHF).
- To understand how LRP2 dysfunction leads to conotruncal malformations.
Main Methods:
- Utilized LRP2-deficient mouse models to study OFT development.
- Examined LRP2 expression in the cardiac progenitor niche of the anterior SHF.
- Analyzed the differentiation and migration of progenitor cells in LRP2-mutant mice.
Main Results:
- LRP2 is expressed in the anterior SHF progenitor niche crucial for OFT elongation.
- Loss of LRP2 leads to premature differentiation of sonic hedgehog-dependent progenitor cells.
- This progenitor cell depletion results in OFT shortening and CAT formation in mutant mice.
Conclusions:
- LRP2 is critical for maintaining the fate of cardiac progenitor cells in the anterior SHF.
- LRP2 dysfunction disrupts OFT separation, causing conotruncal malformations.
- This study identifies a novel molecular mechanism linking LRP2 to congenital heart defects.
