Tissue engineering of the intervertebral disc with cultured annulus fibrosus cells using atelocollagen honeycomb-shaped scaffold with a membrane seal (ACHMS scaffold)

The objective of the study was to investigate the regeneration of intervertebral discs after laser discectomy using tissue engineering procedures. Annulus fibrosus (AF) cells from the intervertebral discs of Japanese white rabbits were cultured in an atelocollagen honeycomb-shaped scaffold with a membrane seal (ACHMS scaffold), to produce a high-density, three-dimensional culture for up to 3 weeks. Although the DNA content in the scaffold increased at a lower rate than that in the monolayer culture, expression of type II collagen and glycosaminoglycan accumulation in the scaffold were at higher levels than in the monolayer. The AF cells that had been cultured in the scaffold for 7 days were allografted into the lacunae of intervertebral discs of recipients (40 rabbits, 14-16 weeks old, average weight, 3.2 kg), whose nucleus pulposus (NP) had been vaporised with an ICG dye-enhanced laser. The allografted cultured AF cells survived and produced hyaline-like cartilage. Furthermore, the narrowing of the intervertebral disc space of the cell-containing scaffold insertion groups was significantly inhibited after 12 post-operative weeks.