Abstract: ObjectiveTo evaluate the feasibility of using injective chitosan scaffold and induced- adipose-derived stromal cells(ADSCs) to construct tissue engineered injectable nucleus pulposus (NP).MethodsADSCs were harvested from rabbits to culture 3 passage and induce 2 weeks to NP-like cells. The injective chitosan hydrogel scaffold was made of chitosan and disodium β-glycerophosphate. Its physical properties and gross condition were observed. The tissue engineered NP was constructed by compounding the scaffold and induced-ADSCs. Then, the viability of ADSCs in the scaffold was observed 2 days after compound culture and the growth condition of ADSCs on the scaffold was observed by scanning electron microscope (SEM) 14 days after compound culture. Expression of aggrecan and Col Ⅱ mRNA in ADSCs were analyzed by RT-PCR 14 days after inductive culture and compound culture.ResultsThe injective chitosan hydrogel was liquid at room temperature and solidified into gel at 37 ℃ (10～15 minutes) due to crosslinking reaction. Acridine orange/propidiumiodide staining showed that the viability rate of induced-ADSCs in chitosan scaffoldl was above 90%. Scanning electron microscope observation demonstrated that the ADSCs were distributed in the reticulate scaffold. RT-PCR results showed that the expression of Col Ⅱ and aggrecan mRNA in induced-ADSCs demonstrated differentiation of ADSCs to a phenotype which showed similarities to NP cells, and the co-culture NP-like cells with scaffold didn`t cause dedifferentiation.ConclusionWith good cellular compatibilities, C/Gp scaffold may be a potential NP cells carrier for tissue engineered NP.

Key words: tissue engineere, intervertebral disc, adipose-derived stromal cells(ADSCs), injective scaffold, thermo-sensitive