Differentiation of immortalized human precartilaginous stem cells into nucleus pulposus-like cells

We aimed to explore the differentiation of immortalized human precartilaginous stem cells (IPSCs) into nucleus pulposus (NP)-like cells induced by transforming growth factor-β1 (TGF-β1) and examine its biological characteristics.

The IPSCs were seeded onto chitosan/glycerophosphate (C/GP) scaffolds and induced into NP-like cells by adding TGF-β1 under hypoxic conditions. The growth and differentiation of IPSCs were observed, and the formation of glycosaminoglycans (GAG) in the extracellular matrix of differentiating cells was detected by Alcian Blue staining. The expressions of type II collagen and aggrecan genes in NP-like cells were examined by reverse transcription-polymerase chain reaction (RT-PCR). The expressions of Sox9 and β-catenin were analyzed by Western blotting.

The IPSCs were observed to grow well on the C/GP scaffolds. After 7 days, Alcian Blue staining demonstrated the formation of GAG. The RT-PCR results showed that expression of type II collagen and aggrecan were upregulated compared with control group (P<0.05, P<0.05). Likewise, western blotting results showed that the expression of Sox9 and β-catenin was upregulated compared with control group (P<0.05, P<0.05).

The findings demonstrate that IPSCs could be differentiated into NP-like cells following induction by TGF-β1.