Related Experiment Video
Updated: Jun 1, 2026
Induction of Endothelial Differentiation in Cardiac Progenitor Cells Under Low Serum Conditions
Published on: January 7, 2019
In vitro and in vivo proliferation, differentiation and migration of cardiac endothelial progenitor cells
S X Liang1, L M Khachigian, Z Ahmadi
1Center for Vascular Research, University of New South Wales, Sydney, NSW, Australia.
Insights
Cardiac side-population (SP) cells, specifically SCA1(+)/CD31(+) CSP cells, were identified as potential endothelial progenitor cells. These cells demonstrate stem cell markers and vascularization capabilities in vitro and in vivo, particularly after myocardial infarction.
Area of Science:
- Cardiovascular Biology
- Stem Cell Research
- Endothelial Cell Biology
Background:
- Side-population (SP) cells, identified by Hoechst dye efflux, are enriched for stem/progenitor activity.
- Cardiac SP (CSP) cells include SCA1(+)/CD31(-) and SCA1(+)/CD31(+) populations.
- SCA1(+)/CD31(-) CSP cells are known cardiac stem/progenitor cells, but SCA1(+)/CD31(+) CSP cells remain poorly characterized.
Purpose of the Study:
- To characterize SCA1(+)/CD31(+) CSP cells in adult mouse hearts.
- To investigate the proliferative, differentiative, vascularization, and migratory potential of SCA1(+)/CD31(+) CSP cells in vitro and in vivo.
Main Methods:
- Fluorescence-activated cell sorting (FACS) and RT-PCR were used for cell identification and gene expression analysis.
- In vitro assays assessed cell proliferation, differentiation, and migration.
- In vivo studies utilized a murine model of myocardial infarction (MI).
Main Results:
- SCA1(+)/CD31(+) CSP cells express stem cell and endothelial-specific genes and are located in blood vessels.
- These cells exhibit proliferation, differentiation, migration, and vascularization capabilities.
- Following MI, SDF-1α and CXCR4 were upregulated, promoting SCA1(+)/CD31(+) CSP cell migration towards the ischemic region, where they formed vascular tube-like structures.
Conclusions:
- SCA1(+)/CD31(+) CSP cells possess characteristics of endothelial progenitor cells.
- Their gene expression, localization, and functional abilities support their role in cardiac vascularization.
- These cells may contribute to myocardial repair after injury.
Background:
Side-population (SP) cells are a select population identified by a capacity to efflux Hoechst dye and are enriched for stem/progenitor cell activity. Previous studies suggested that cardiac SP (CSP) cells could be divided into SCA1(+)/CD31(-) and SCA1(+)/CD31(+) CSP cells. SCA1(+)/CD31(-) CSP cells have been shown to be cardiac stem/progenitor cells. However, SCA1(+)/CD31(+) CSP cells have not been fully characterized.
Objective:
The aim of the present study was to characterize SCA1(+)/CD31(+) CSP cells in the adult mouse heart, and investigate their abilities to proliferate, differentiate, vascularize and migrate in vitro and in vivo.
Results:
Using fluorescence-activated cell sorting (FACS), RT-PCR, and assays of cell proliferation, differentiation and migration, and a murine model of myocardial infarction (MI), we showed that SCA1(+)/CD31(+) CSP cells express stem cell and endothelial-specific genes, and reside in the blood vessels. These cells were able to proliferate, differentiate, migrate and vascularize in vitro and in vivo. After MI, SDF-1α and CXCR4 were up-regulated in the damaged myocardium and on SCA1(+)/CD31(+) CSP cells, respectively. Our results further showed that SDF-1α induced migration of these cells in vitro. Importantly, we found that SCA1(+)/CD31(+) CSP cells could migrate into the ischemic region from the non-ischemic area within the myocardium and form a vascular tube-like structure after MI.
Conclusions:
Based on the gene expression profile, localization of SCA1(+)/CD31(+) CSP cells, and their ability to proliferate, differentiate, migrate and vascularize in vitro and in vivo, we postulate that SCA1(+)/CD31(+) CSP cells may represent endothelial progenitor cells in the mouse heart.
