Subpopulation analysis of Sca-1, Nanog, and Islet-1 positive cells in myocardial tissue

To investigate the co-expression between different stem-cell or embryonic markers in myocardial tissue, which has rarely been discussed in previous studies, we selected three typical molecular markers, namely Sca-1, Nanog and Islet-1. In our study, we focused on the age-related changes of Sca-1, Nanog and Islet-1 expression and the co-localization levels between pin-two marker proteins to explore the heterogeneity and relevance between these three cell subpopulations. We found that Sca-1, Nanog, and Islet-1 positive cells were present in the cardiac tissue from newborn to adult mice, and their expression was negatively correlated with age. Co-localization existed between each two markers, and there were differences in co-localization levels at different stages of cardiac development. We thus hypothesize that these three positive cells are likely to be a group of cells, so that cardiac cells with myocardial differentiation potential should not be subclassified by a single cell marker, and their phenotypic changes at different stages may determine their unique roles in heart development.