Multi-potent progenitors in freshly isolated and cultured human mesenchymal stem cells: a comparison between adipose and dermal tissue

Abstract

Mesenchymal stem cells (MSCs) from human adult adipose tissue (A-MSCs) have a better differentiative ability than MSCs derived from the derma (D-MSCs). To test whether this difference is associated with differences in the content of multi-potent progenitors in A-MSCs, the number and the differentiative properties of multi-potent progenitors have been analyzed in various preparations of A-MSCs and D-MSCs. Adipogenic and osteogenic differentiation performed on colony-forming units have revealed that adipogenic and osteogenic progenitors are similar in the two populations, with only a slighty better performance of A-MSCs over D-MSCs from passages p0 to p15. An analysis of the presence of tri-, bi-, uni- and nulli-potent progenitors isolated immediately after isolation from tissues (p0) has shown comparable numbers of tri-potent and bi-potent progenitors in MSCs from the two tissues, whereas a higher content in uni-potent cells committed to adipocytes and a lower content in nulli-potent cells has been observed in A-MSCs. Furthermore, we have characterized the progenitors present in A-MSCs after six passages in vitro to verify the way in which in vitro culture can affect content in progenitor cells. We have observed that the percentage of tri-potent cells in A-MSCs at p6 remains similar to that observed at p0, although bi-potent and uni-potent progenitors committed to osteogenic differentiation increase at p6, whereas nulli-potent cells decrease at p6. These data indicate that the greater differentiative ability of A-MSC populations does not correlate directly with the number of multi-potent progenitors, suggesting that other factors influence the differentiation of bulk populations of A-MSCs.

Enrichment and Characterization of Human Dermal Stem/Progenitor Cells by Intracellular Granularity

“…We previously reported that there were no meaningful differences in the expression levels of MSC-specific surface markers such as CD44, CD73, CD90, and CD105 between collagen type IV-sorted hDSPCs and collagen type IV-sorted non-hDSPCs [28]. Taken together, these results indicate that SSC highhDSPCs may be another type of progenitor cells derived from human dermis, which are different from the previously isolated multipotent fibroblasts and SKPs [13][14][15][16]45].…”

“…Previous studies demonstrated that human dermisderived multipotent fibroblasts by clonal isolation are negative for nestin and positive for vimentin representative intermediate filament proteins [16,45]. On the other hand, another group showed that SKPs derived from the human foreskin specifically express both nestin and vimentin in suspension cultures [13,15].…”

“…Homogenous hDSPCs can be isolated by identification of specific surface markers, which will also provide an efficient way for studying the physiological roles of hDSPCs. Although specific cell surface markers of multipotent fibroblasts or SKPs have been extensively explored [15,16,45,58,59], no unique markers have been definitively established. Thus, we will investigate novel specific markers for the isolation of the homogenous hDSPCs populations.…”

“…According to previous reports, adult human dermal fibroblasts are a heterogeneous cell population comprising multipotent stem/ progenitor cells and fully differentiated fibroblasts [16,28,45].…”

Adult Stem Cell Subsets from Adult Human Dermis

“…This multi-lineage capacity differs among niches, conditions, and duration of in vitro culture [3][4][5][6][7]. The hMSC cell surface signature enables the ability to identify and isolate certain stromal-like cell derivatives, which can undergo ex vivo differentiation resulting in committed cell lineages [1,8].…”