In vitro culture of human adipose-derived stem cells and their differentiation into chondrocytes

Objective To investigate the biological features of human adipose-derived stem cells(ADSCs) to isolate and culture,then differentiate into adipocyte and chondrocyte in vitro,and discuss the feasibility of ADSCs as seed cells in cartilage tissue engineering.Methods(1)Human adipose was obtained from the healthy womenhood during the abdominal liposuction procedure and digested with collagenaseⅠto isolate ADSCs,which were incubated in vitro.(2)Growth curve of the third-passage ADSCs was drawn by cytometry;The expressions were assayed by flow cytometry and immunofluorescence technique;The third-passage ADSCs were differentiated into adipogenic and chondrogenic inductions.(3)ADSCs were observed under inverted microscope,and the differentiations into adipocyte and chondrocyte were verified by oil red O staining,AB-PSA staining,immunocytochemical staining and RT-PCR.Results(1)ADSCs cultured in vitro were stably passaged,during which ADSCs kept the same shape.(2)ADSCs cultured in adipogenic differentiation medium developed intracellular vacuoles that accumulates the lipid dye oil red O,and in chondrogenic differentiation medium,AB-PSA staining was positive and the type Ⅱcollagen immunocytochemical staining appeared positive with brown cytoplasm.In using RT-PCR,we could see expressions of Leptin,PPAR-γ and of COLLⅡ,SOX9,aggrecan in the two mediums separately.Conclusion ADSCs can be induced to differentiate towards chondrocytes,and used as seed cells for cartilage tissue engineering.