[Effect of cryopreservation on growth and osteogenesis of human adipose-derived stem cells]
Guangpeng Liu1, Yulin Li, Jian Sun
1Department of Plastic and Reconstructive Surgery, Ninth People's Hospital, Medical College of Shanghai Jiaotong University, National Tissue Engineering Research and Development Center, Shanghai 200241, PR China.
Objective:
As one of the adult stem cells, adipose-derived stem cells (ADSCs) have become an important seed cell source for tissue engineering recently. But whether the thawed cryopreserved ADSCs could be used to tissue engineered bone remains unknown. To investigate the effect of cryopreservation on the growth and osteogenesis of ADSCs in vitro.
Methods:
The ADSCs were isolated from the adipose aspirates by collagenase digestion method. For the experimental group, the 2nd generation cells were stored with a simple method of cryopreservation by slow cooling with dimethyl sulphoxide as a cryoprotectant and rapid thawing. After cryopreserved in liquid nitrogen for 4 weeks, ADSCs were recovered and cultured in osteogenic media, with non-cryopreserved ADSCs as the control group. The osteogenic differentiation was evaluated by alkaline phosphatase (ALP) staining and Alizarin red O staining at 2 and 3 weeks respectively. The cell growth and osteogenesis of ADSCs were further determined using DNA assay and the ALP activity and calcium content were measured.
Results:
The survival percentage of the cryopreserved cells was 90.44% +/- 2.62%. The cell numbers and ALP activity increased with osteogenic induction time, and reach plateaus at 7 days and 11 days, respectively. The ALP staining and Alizarin red O staining results were both positive at 2 weeks and 3 weeks after osteogenic induction, respectively. And no significant difference in the cells number, ALP activity, and calcium content were found between experimental group and control group (P > 0.05).
Conclusion:
Cryopreservation does not affect the growth and osteogenesis of ADSCs, and the cryopreserved ADSCs can be used as cell source for tissue engineered bone.
