Background: A variety of adult stem cells have been transplanted into the infarcted heart to cure myocardial infarction(MI), however, comparative studies are lacking to show more suitable source of cells for transplantation. Mesenchymal stem cells hold promise for myocardial regeneration therapy. Derivation of these cells from the endometrium tissue might be easier compared to bone marrow and adipose tissue. However,the in vivo fate of endometrium stem cells (EnSCs) in the infarcted heart has never been compared directly to mesenchymal cells derived from bone marrow(BMMSCs) and adipose tissue(AdMSCs).
Methods: EnSCs, AdMSCs and BMMSCs were isolated from healthy donors were characterized using flow cytometry for surface markers identification and microscopy for cell morphology. They were characterized with β-actin promoter driving firefly luciferase and green fluorescent protein (Fluc-GFP) double fusion reporter gene, and were characterized using flow cytometry, bioluminescence imaging (BLI) and luminometry. Cell proliferation was tested by CCK-8 kit, colony forming unit(CFU) was stained by crystal violet staining and apoptosis ratio were detected by TUNEL assay. Rat (n=8/group) underwent myocardial infarction followed by intramyocardial injection of 5х105 EnSCs, AdMSCs and BMMSCs, or saline (negative control). Cell survival was measured using BLI for 6 weeks and cardiac function was monitored by echocardiography and hemodynamics analysis. Ventricular morphology was assessed using histology.
Results: EnSCs, AdMSCs and BMMSCs were CD29+, CD90+, CD105+, shared similar morphology, but EnSCs had best proliferation, colony-forming and anti-apoptosis activity of 3 types of MSCs. Cells expressed Fluc reporter genes in a number-dependent fashion, as confirmed by luminometry. After cardiac transplantation, transplantation of EnSCs was better capable of preserving ventricular function and dimensions than others, as confirmed by echo test, PV-loops and histology.
Conclusions: This is the first study comparing the in in vitro and in vivo behavior of 3 types of MSCs in the infarcted heart. AdMSCs and BMMSCs do not tolerate well in the cardiac environment, resulting in more cell death andworse cardiac function than EnSCs groups.