Related Experiment Video
Updated: May 5, 2026
Manual Isolation of Adipose-derived Stem Cells from Human Lipoaspirates
Published on: September 26, 2013
Mechanical Manipulation of Fat: From Lipoaspirate to Stromal Vascular Fraction Concentrate
Kjersti Ausen1,2,3, Anne D B Rø4,2, Gunnhild V Leirvik4,2
1From the Section for Plastic and Reconstructive Surgery.
Background:
The adipose stromal vascular fraction (SVF) is a mesh of connective tissue, capillaries, stem cells, and supportive cells that may have regenerative properties. Attention is shifting from enzymatic isolation and expansion of the stem cell population alone to the benefit of preserving the SVF as a functional unit. Enzymatic breakdown of lipoaspirate is time-consuming and involves use of foreign substances. The authors have established a simple procedure for perioperative mechanical isolation of SVF. This study investigates how mechanical fractionation and centrifugation changes the qualities of lipoaspirate.
Methods:
Three derivatives of manipulated fat were defined: washed and centrifuged lipoaspirate (Coleman fat), mechanically fractionated Coleman fat (nanofat), and SVF concentrate obtained by hard centrifugation of nanofat. The end products were characterized by flow cytometry, proliferation capacity measured as time to confluence, and histologic and cytologic characteristics.
Results:
Viable stem cells are preserved during vigorous mechanical fractionation of dry lipoaspirate to nanofat. A sedimented SVF concentrate from centrifugated nanofat has a high stem cell concentration. A nanofat "mayonnaise problem" may require a salvage procedure to enable centrifugal separation. Proliferation is significantly but marginally delayed in SVF cells from fractionated fat versus nonmanipulated lipoaspirate. Histology and cytology demonstrate the presence of micrografts in SVF concentrate (ie, capillary fragments with SVF cells attached).
Conclusions:
SVF concentrate manufactured by mechanical fractionation and centrifugation contains viable cells capable of proliferation. SVF concentrate contains vascular micrografts that may be injected alone for regenerative purposes or added to nonmanipulated lipoaspirate for stem cell-enriched fat transfer.
Clinical Relevance Statement:
The procedures described in this article, and the illustrative videos, are relevant to all plastic surgeons involved in regenerative fat grafting. The methods require no special equipment and can be instantly adopted.
