Cell biological study of adipose-derived stem cells

Objective To explore a approach to isolate and culture adipose-derived stem cells (ASCs) from the adipose tissue of liposuction aspirates, and conduct observations of the cell growth kinetics, morphology, differentiation capability, cell aging, and surface marker profiles. Methods From the liposuction aspirates, ASCs were isolated by means of enzymatic digestion, and the appearance of the cultured cells was observed. The cell viability was evaluated with MTT chromatometry and cell growth curve was generated. Flow cytometry was performed for cell cycle analysis, and acridine orange staining was utilized for cell aging evaluation. The expressions of the cell surface marker profiles were detected by flow cytometry and immunohistochemistry. Adipogenic differentiation of ASCs was assessed by Oil Red O staining. Results Primarily cultured ASCs adhered to the culture plates with a fibroblastic appearance and strong proliferation capacity as shown by MTT chromatometry. ASCs also showed characteristic stem cell cycle. Acridine orange staining of the ASCs at passages 3, 4, 6, and 8 did not reveal evidence of obvious cell aging. The expressions of CD29, CD44, and CD34 were observed in ASCs by flow cytometry while HLA-DR or CD133 expression was not detected. Expressions of VШ factor, CD31, CD34, CD105 and SMA were observed in ASCs by immunohistochemistry. Oil Red O staining of the ASCs after 2 weeks of culture demonstrated numerous intracellular lipid droplets. Conclusion ASCs can be isolated from autologous liposuction aspirates of human via enzymatic digestion and cultured ex vivo. These cells are fibroblast-like cells expressing cell surface markers of stem cells with strong proliferative ability, and can be induced to differentiate into adipose tissue.