Experimental research on differentiation of immortalized human precartilaginous stem cells to nucleus pulposus-liked cells induced by TGF-β1 / 中华骨科杂志

ABSTRACT

Objective To explore the possibility of immortalized human precartilaginous stem cells (IPSCs) differentiating into nucleus pulposus-liked cells induced by transforming growth factor-β1 (TGF-β1)and examine its biological characters.Methods The IPSCs were seeded on the thermosensitive chitosan/glycerophosphate (C/GP) scaffolds and induced into nucleus pulposus-like cells in culture medium with the adding of TGF-β1 under hypoxia condiction.The growth and differrentiation of IPSCs on C/GP scaffolds were observed.Seven days later,Alcian blue staining was used to detect the formation of glycosaminoglycans (GAG) of extracellular matrix by the differentiating cell.RT-PCR was carried out to identify the expression of characteristic genes of nucleus pulposus-liked cells,including collagen Ⅱ and Aggrecan.Western blot were used to examine the expression of β-catenin.Results IPSCs grew well on the thermosensitive C/GP scaffolds.After 7 days,Alcian blue staining exhibited more formation of GAG in experimental group as compared with control group.RT-PCR manifested that the gene expression of collagen Ⅱ and Aggrecan were upregulated.Likewise,Western blot manifested that the expression of β-catenin was upregulated.Respectively,all of the content in the induction group obviously increased compared with that of the control group.Conclusion IPSCs can be differentiated into nucleus pulposus-like cells under the induction of TGF-β1,the differentiating cells have a favourable secretory function,which can secrete extracellular matrix effectively.Differentiation of IPSCs to nucleus pulposus-liked cells may be through upregulating the expression of β-catenin in cells.