Construction of tissue-engineered composite intervertebral disc and preliminary morphological and biochemical evaluation

The aim of this study was to construct tissue-engineered composite intervertebral disc (IVD) consisting of demineralized bone matrix gelatin (DBMG) and collagenII/hyaluronate/chondroitin-6-sulfate (CII/HyA–CS) scaffolds seeded with anulus fibrosus (AF) and nucleus pulposus (NP) cells, respectively. The cell-scaffold hybrids were implanted in the subcutaneous space of the dorsum of athymic mice and harvested at 4, 8, and 12 weeks. At each time point, the gross and histological morphology and biochemical properties were evaluated. Our results are as following: the gross morphology and histology of the composite resembled those of native IVD. Morphological studies revealed progressive tissue formation and junction integration between AF and NP regions. Biochemical composition detection indicated that the content of DNA, proteoglycan and hydroxyproline increased with time, and were similar to native tissue at 12 weeks. All these results demonstrated the feasibility of creating a tissue-engineered composite IVD with similar morphological and biochemical properties to the native tissue.

► A novel method of creating a tissue-engineered composite IVD.
► The composite IVD consists of DBMG and CII/HyA–CS scaffolds seeded with AF and NP cells, respectively.
► The morphological and biochemical properties of the IVD composite resemble those of native IVD.
► The constructed composite showed progressive tissue formation with time.