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Induction of Endothelial Differentiation in Cardiac Progenitor Cells Under Low Serum Conditions
Published on: January 7, 2019
Isolation of resident cardiac progenitor cells by Hoechst 33342 staining
Otmar Pfister1, Angelos Oikonomopoulos, Konstantina-Ioanna Sereti
1Myocardial Research, Department of Biomedicine, and Division of Cardiology, University Hospital Basel, Basel, Switzerland.
Insights
Researchers identified cardiac progenitor cells using a side population (SP) technique. These SP cells, expressing stem cell antigen 1 (Sca-1) but not CD31, are crucial for maintaining heart health and function.
Area of Science:
- Cardiovascular Biology
- Stem Cell Research
Background:
- Resident cardiac progenitor cells are vital for maintaining myocardial homeostasis and heart function.
- Identifying these cells is crucial for advancing cardiovascular research and regenerative medicine.
Purpose of the Study:
- To describe the methodology for isolating resident cardiac progenitor cells.
- To characterize cardiac progenitor cells using the side population (SP) phenotype and stem cell surface markers.
Main Methods:
- Utilizing the side population (SP) phenotype, identified by Hoechst 33342 dye efflux during fluorescence-activated cell sorting (FACS).
- Combining SP identification with cell surface marker analysis, specifically stem cell antigen 1 (Sca-1) and CD31.
Main Results:
- Cardiac SP cells expressing Sca-1 but lacking CD31 were identified.
- These identified cells demonstrated cardiomyogenic potential, confirming them as putative cardiac progenitor cells.
Conclusions:
- The SP phenotype, in conjunction with specific cell surface markers (Sca-1+/CD31-), provides a reliable method for isolating resident cardiac progenitor cells.
- This isolation technique is essential for further understanding the role of cardiac progenitor cells in myocardial biology and disease.
Abstract:
Cardiac resident stem/progenitor cells are critical to the cellular and functional integrity of the heart by maintaining myocardial cell homeostasis. Given their central role in myocardial biology, resident cardiac progenitor cells have become a major focus in cardiovascular research. Identification of putative cardiac progenitor cells within the myocardium is largely based on the presence or absence of specific cell surface markers. Additional purification strategies take advantage of the ability of stem cells to efficiently efflux vital dyes such as Hoechst 33342. During fluoresence activated cell sorting (FACS) such Hoechst-extruding cells appear to the side of Hoechst-dye retaining cells and have thus been termed side population (SP) cells. We have shown that cardiac SP cells that express stem cell antigen 1 (Sca-1) but not CD31 are cardiomyogenic, and thus represent a putative cardiac progenitor cell population. This chapter describes the methodology for the isolation of resident cardiac progenitor cells utilizing the SP phenotype combined with stem cell surface markers.
