A comparison of pluripotency and differentiation status of four mesenchymal adult stem cells.

The self-renewal and differentiation status of a stem cell is very important in the applications concerning regenerative medicine. Proliferation capacity, differentiation potentials and epigenetic properties of stem cells differ between sources. Studies have shown the high potentials of stem cells in iPS reprogramming. To examine this; we have compared the stem-ness and differential potential of four adult stem cells from common sources. We show a correlation between pluripotency and differentiation status of each stem cell with available data on the reprogramming efficiency. Four human adult stem cells including, adipose tissue-mesenchymal stem cells (AT-MSC), bone marrow mesenchymal stem cells (BM-MSCs), nasal septum derived multipotent progenitors (NSP) and umbilical cord blood stem cells (USSCs) were isolated and characterized. The self- renewal and differentiation potentials of each stem cell were assessed. Stem-ness transcription factors and the propagation potentials of all cells were analyzed. Furthermore the differentiation potentials were evaluated using treatment with induction factors and specific MicroRNA profile. Real-time PCR results showed that our stem cells express innate differentiation factors, miR145 and Let7g, which regulate the stem-ness and also the reprogramming potentials of each stem cell. To complete our view, we compared the propagation and differentiation potentials by correlating the stem-ness gene expression with differentiation MicroRNAs, also the direct effect of these factors on reprogramming. Our results suggest that the potentials of adipose tissue stem cells for GMP (Good Manufacturing Practice) compliant starting material are adequate for clinical applications. Our results indicate a low risk potential for AT-MSCs as starting material for iPS production. Although let7g and mir145 are well known for their differentiation promoting effects, but function more of a fine tuning system between self-renewal and differentiation status.