Regulation of adipose-derived adult stem cells differentiating into chondrocytes with the use of rhBMP-2.
BACKGROUND
Adipose tissue has been demonstrated to contain a population of progenitor cells that can differentiate into bone and cartilage. Studies have suggested that adipose-derived adult stem (ADAS) cells can be induced to differentiate into chondrocytes by transforming growth factor-beta (TGF-beta). In this study, we examined whether bone morphogenetic protein-2 (BMP-2), as a member of the TGF-beta superfamily, could regulate ADAS cells to differentiate into a chondrolineage.


METHODS
ADAS cells were isolated and induced by rhBMP-2. These cells were cultured in pellets for 2 weeks, and the chondrogenic phenotype was observed in vitro and in vivo. ADAS cells cultured without BMP-2 were used as controls.


RESULTS
After 2 weeks of culture, the differentiated ADAS cells reacted positively to Alcian blue and collagen II, and the content of collagen II protein was obviously up-regulated at day 14. Glycosaminoglycan (GAG) content gradually increased from day 2 to day 14 (P < 0.05). However, H&E staining and collagen II expression were weak, and there was a little collagen II protein and GAG detected in the control group. Additionally, the pellets of ADAS cells induced by rhBMP-2 were transplanted into BALB/C nude mice and formed cartilage lacuna at week 8 in vivo.


CONCLUSIONS
These data demonstrate that rhBMP-2 induce ADAS cells to differentiate into chondrocytes in vitro and in vivo. This is useful for basic and clinical studies aimed at repairing cartilage damage. But in a control group, ADAS cells tended towards differentiation into chondrocytes, which was affected by ITS. We will be exploring the mechanism further.
Wei
Y
Y
Institute of Orthopaedics and Traumatology, Xijing Hospital, The Fourth Military Medical University, Xi'an, People's Republic of China.
Hu
Y
Y
Lv
R
R
Li
D
D
D000273:Adipose Tissue / Q000166:cytology*; D053687:Adult Stem Cells / Q000502:physiology*; D000818:Animals; D000954:Antigens, Surface / Q000032:analysis; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D002454:Cell Differentiation; D019902:Chondrocytes / Q000502:physiology*; D020219:Chondrogenesis; D024043:Collagen Type II / Q000032:analysis; D015683:Gene Products, gag / Q000032:analysis; D007120:Immunochemistry; D051379:Mice; D008807:Mice, Inbred BALB C; D011817:Rabbits; D033581:Stem Cell Transplantation; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D014183:Transplantation, Heterologous
D000954:Antigens, Surface; C525719:Bmp2 protein, mouse; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D024043:Collagen Type II; D015683:Gene Products, gag; D016212:Transforming Growth Factor beta