Xenogen-free isolation and culture of human adipose mesenchymal stem cells

Background: Adipose-derived Stem Cells (ASCs) present great potential for reconstructive procedures. Currently, isolation by enzyme digestion and culturing using xenogenic substances remain the gold standard, impairing clinical use. Methods: Abdominal lipo-aspirate and blood samples were obtained from healthy patients. A novel mechanical isolation method for ASCs was compared to (the standard) collagenase digestion. ASCs are examined by flow-cytometry and multilineage differentiation assays. Cell cultures were performed without xenogenic or toxic substances, using autologous plasma extracted from peripheral blood. After eGFP-transfection, an in vivo differentiation assay was performed. Results: Mechanical isolation is more successful in isolating CD34(+)/CD31(-)/CD45(-)/CD13(+)/CD73(+)/CD146(-) ASCs from lipo-aspirate than isolation via collagenase digestion (p < 0.05). ASCs display multilineage differentiation potential in vitro. Autologous plasma is a valid additive for ASCs culturing. eGFP-ASCs, retrieved after 3 months in vivo, differentiated in adipocytes and endothelial cells. Conclusion: A practical method for human ASC isolation and culturing from abdominal lipo-aspirate, without the addition of xenogenic substances, is described. The mechanical protocol is more successful than the current gold standard protocol of enzyme digestion. These results are important in the translation of laboratory-based cell cultures to clinical reconstructive and aesthetic applications