Comparative study on chondrogenic differentiation of adipose-derived stem cells induced by different methods

Abstract

Objective To compare the effect of coculture with chondrocytes or culture with induction medium on chondrogenic differentiation of adipose-derived stem cells (ADSCs).Methods ADSCs and chondrocytes were isolated from rabbits and cells of passage 2 were collected.The study contained 3 groups:ADSCs were cultured with common high glucose culture medium in a 6-well plate in control group,chondrocytes and ADSCs were separately seeded on the upper and lower layers of Transwell six-well plate and cultured with common high glucose culture medium in coculture group,ADSCs were cultured with induction medium in a 6-well plate in induction medium group.ADSCs were observed under inverted contrast phase microscope for morphological changes and harvested 14 days after incubationfor toluidine blue staining and collagen type Ⅱ immunohistochemistry staining.Quantitative real-time PCR was used to detect and quantify chondrocyte-specific genes (collagen type Ⅱ,aggrecan and SOX9).Results ADSCs in coculture group and induction medium group showed a chondrocytes-like morphology.Toluidine blue staining and immunohistochemistry staining were positive in coculture group and induction medium group with relatively deeper staining in induction medium group,while the results were negative in control group.Quantitative real-time PCR indicated that the transcriptional levels of collagen type Ⅱ,aggrecan and SOX9 in coculture group (1.427 ± 0.066,2.128 ± 0.076 and 1.082 ± 0.081) were lower than those in induction medium group (3.438 ± O.108,4.297 ± 0.147 and 2.929 ± 0.090,P ＜ 0.05),but all were higher than those in control group (0.040 ± 0.021,0.128 ± 0.038 and 0.098-± 0.022,P ＜0.05).Conclusion ADSCs can differentiate into cartilage-like cells after co-culturing with chondrocytes or culturing with induction medium,but induction medium has better differential effect. Key words: Stem cells; Chondrocytes; Cell differentiation