[Cell biological study of cultured cells derived from the fattyoffluid portions of liposuction aspirates].

OBJECTIVE: To explore an approach to isolate and culture the Adipose derived stem cells (ASCs) from the fatty and the fluid portions of liposuction aspirates, and to investigate the growth kinetics, morphology, differentiation capability, cell senescence, surface marker profiles of the ASCs.

METHODS: The liposuction aspirates were divided into fatty portion and liquid portion. ASCs were isolated from each portion by collagenase digestion and directly centrifugate and cultured to observe the morphology and biology characters in vitro. Cell activity was studied by MTT chromatometry and analyzed statistically. Cell cycle was detected by flow cytometry. Cells were randomly selected from the 3rd, 4th, 6th, 8th generation cells to detect senescence of ASCs by acridine orange staining. The cell surface markers were detected by flow cytometry and immunohistochemistry. Adipogenic and osteogenic lineage differentiation of ASCs was assessed by Oil Red O and alizarin bordeaux staining respectively.

RESULTS: A large amount of ASCs could be isolated and cultured both from the fatty portion and the liquid portion, including PLA cells and LAF cells which had fibroblastic characters with strong viability and proliferative activity. The statistical result indicated that the cell activity of PLA cells and LAF cells was very similar. ASCs from passage 3, 4, 6, 8 didn't show insenecence. CD29, CD44, CD34, which were the markers of mesenchymal stem cells, vWF, CD31, CD105, SMA were all expressed in ASCs. Adipogenic differentiation of ASCs was assessed by Oil Red O staining after 2 weeks. The cells contained many lipid-filled droplets. After 2 weeks' osteogenic induction, cells were positively stained by alizarin Bordeaux.

CONCLUSIONS: The method can isolate ASCs by directly centrifugate from the fatty and the fluid portions of human liposuction aspirates. The way of culture is convenient and economical. ASCs isolated from the liquid and fatty portions of liposuction aspirates show identical in cells numbers and quality. LAF cells and PLA cells have similar characters in growth dynamics, morphology, cell senescence, surface marker profiles and differentiation ability, etc. Expression of the cell surface marker of stem cells is also observed in ASCs. ASCs can differentiate into adipose and osteogenesis directionally. The results suggest that the ASCs, which are isolated with minimum intervention, may be the ideal seed cells for adipose tissue engineering in future.