Purpose

ADSCs represent a population of adult MSCs able to self-renew and differentiate into different cell lineages that play key role in regenerative medicine and tissue engineering, alone or in combination with biomaterials, growth factors or different types of scaffolds. Subcutaneous adipose tissue is becoming the first choice for cell isolation since it is easily accessible, relatively abundant and can be harvested by an absolutely minimally invasive procedure in order to be transplanted to either an autologous or an allogeneic host.

Our aim is to compare fresh ADSCs isolated from adipose tissue samples extracted with different surgical procedures and evaluate their biologics, integrity and viability.

Methods and Materials

ADSCs have been isolated from tissue samples obtained with different commercially available withdrawal systems. As the use of enzymes might have impact on safety and efficacy, we decided to focus attention only on non-enzymatic isolation systems. In particular, we compared adipose samples extracted with the Lipogems system versus different types of lipoaspirate samples, obtained with systems basing processing action on mechanical dissociation of adypocites and isolation of all SVC cells: ADSCs, pericytes, endothelial and progenitor stem cells embedded. The output was characterized in terms of viability and cell composition using multicolor FACS analysis.

Results

Multicolor FACS analysis revealed that SVF is composed of heterogeneous cell populations including blood-derived cells (CD45+), ASCs (CD31−CD34+CD45−CD90+CD105−CD146−), endothelial (progenitor) cells (CD31+CD34+CD45−CD90+CD105lowCD146+), pericytes (CD31−CD34−CD45−CD90+CD105−CD146+), and other cells.

In our hands, the cell viability among all the different extraction methods was overall comparable. Nevertheless, we found an dramatic increase in the percentage of endothelial cells in the Lipogems obtained samples (15%) compared to others liposuction methods (2,5%).

Conclusion

Histological studies indicate that a stem cell population resides in a perivascular location, where ADSCs coexist with pericytes and endothelial cells. Our data suggest that the heterogeneity of the population can be maintained by the procedure that preserves the tissue architecture (niche).