The Effect of Patient Characteristics, Harvesting Technique and Anatomic Site Selection On Yield, Growth and Potency of Adipose Derived Stem Cells

Purpose:

Adipose-derived stem cells (ASCs) are emerging as a method to harvest adult stem cells capable of differentiation into a number of cell types associated with the mesenchymal lineage¹. Accordingly, the stromal vascular fraction (SVF) derived from adipose tissue contains an abundance of ASCs that can differentiate into fat, bone, cartilage, muscle and endothelial cells.  This study is directed by the hypothesis that the SVF cellular yield and ASC growth are affected by demographics, harvesting technique and harvest site.

Methods:

Adipose was obtained via en-bloc resection or tumescent liposuction. Forty-five adipose samples were collected from subject's arm, thigh, abdomen, or flank.  Growth curves were obtained by incubating samples for average 14 days with periodic cell counts using Coulter Counter.  Cells were also cultured in osteogenic, adipogenic and endothelial cell differentiation media for 14-21 days.  qRT-PCR was used with osteocalcin, lipoprotein lipase; CD31 as markers for differentiated osteocytes, adipocytes, and endothelial cells, respectively.  

Results:

There was no difference in gender or age in regards to SVF yield.  Obese subjects and those with a history of smoking trended towards a decreased SVF yield.  There was not a statistically significant difference in the SVF yield between adipose tissue harvested by liposuction versus resection. However, there was a statistically significant difference in total cell yield based on anatomic site; highest yield from the upper arm (fig). Cell doubling time was shorter for ASCs from lipoaspirated tissue. Thigh cells trended towards a shorter doubling time.   ASCs isolated from the arm have greater osteogenic differentiation ability than the abdomen and flank.  ASCs differentiated into adipocytes, osteocytes, and endothelial cells expressed appropriate markers using qRT-PCR.

Conclusions:

Our results show that gender, age or harvesting technique does not affect SVF yield. Smoking and obesity show a trend toward decreasing SVF yield. Cells harvested from the arm have shown a difference in the SVF cellular yield and differentiation ability. Our findings suggest that ASCs from different harvesting techniques and anatomic sites may affect SVF yield and ASC growth.

References:

1.     Coleman SR. Structural Fat Grafting: More Than a Permanent Filler. Plastic and  Reconstructive Surgery 2006; 118(3 Suppl):108S-120S

2.     Zuk P, Zhu M, Ashjian P, et al.  Human Adipose Tissue Is a Source of Multipotent Stem Cells.  Molecular Biology of the Cell 2002; 13: 4279-4295.