Characteristics of human subepicardial adipose tissue-derived stem cells

Here, we report on the isolation and characterization of human subepicardial adipose tissue- derived cells with stem cell properties (hcADSCs). The morphology, proliferative activity, karyotype, phenotype, and differentiation potential of these cells at early and late passages were analyzed. Cytogenetic analysis showed that after five passages hcADSCs retained a genetic stability while passage 12 cells exhibited a number of genetic abnormalities such as chromosomal aneuploidy and multi-ploidy karyotypes. Immunophenotyping revealed that the passage 5 hcADSCs lacked expression of the hematopoietic line markers CD34 and HLA class II, and cancer stem cell marker CD133, but were strongly positive for mesenchymal stem cells markers CD13, CD44, and CD73, and CD90. These cells were also moderately positive for CD11b, CD41, CD45, CD71, CD117, CD130, and HLA class I antigens. The hcADSC surface marker profile changed by passage 16 showing decrease in CD41 and increases in CD 117 expression. Cultured hcADSCs were capable of both spontaneous and directed differentiation. By culturing without any induction factors, hcADSC population contained the cells exhibiting the markers characteristic of endothelial cells and myocytes, and at late passages also of adipocytes. In appropriate induction media, hcADSCs could also be differentiated into osteogenic and chondrogenic lineages. Our findings suggest that human subepicardial adipose tissue contains the resident capable of self-renewal cell population which represents a heterogeneous mixture of progenitor cells with varied differentiation potential. These cells possess a number of specific phenotypic and differentiation characteristics. Revealed peculiar properties of hcADSCs might make them a promising candidate for cellular heart therapy.