OBJECTIVETo compared the biological characteristics of adipose-derived stem cells and lipoma-derived mesenchymal stem cells (LMSCs) in vitro, so as to assess the safety of adipose-derived stem cells( ASCs) for transplantation.

METHODSRegular slice and stain of adipose and lipoma tissue were performed. ASCs and LMSCs were isolation from the two tissues by enzymatic digestion, and the appearance of the cultured cells was observed. The cell viability was evaluated with MTS chromatometry and cell growth curve was generated. Flow cytometry was performed for cell cycle analysis and the expression of the cell surface marker profiles. QRT-PCR was used to detect the expression of tumor-specific gene (the high-mobility group AT-hook 2, HMGA2), and immunocytochemistry was used to detect the expression of telomerase.

RESULTSMarked difference was observed in histologic sections of adipose tissue and lipoma tissue. ASCs showed a good consistent in cell morphology while LMSCs not. ASCs showed a significant lower proliferation capacity than LMSCs by MTS chromatometry (P = 0.000). The expression of CD29, CD44, CD105 was similar in ASCs and LMSCs, while the level of CD133 was significantly lower in ASCs (5.35%) than in LMSCs (26.87%). The expression of HMGA2 was lower in ASCs (RQ = 1) than in LMSCs (RQ = 1.79) by qRT-PCR, it has statistically difference between them (P < 0.01); And in ASCs and LMSCs, the integrated optical intensity (IA) values of hTERT expression are 1379.597 +/- 498.617 and 3 328.108 +/- 902.856, size (area) are 132,390.27 +/- 35,568.945 and 238,000.53 +/- 49,264.289, density (mean) are 0.009 +/- 0.003 and 0.014 +/- 0.003, revealed the expression of hTERT also shown a significant lower level in ASCs than in LMSCs by immunocytochemistry.

CONCLUSIONSIt indicates significant difference between ASCs and LMSCs in the biological characteristics in vitro. There is no evidence of malignant transformation of ASCs.