The Study of the Regeneration of Nucleus Pulposususing Nanofiber-based Scaffold : In Vitro and Animal Study

Choi, Jang Seok; An, Ki Chan; Jang, Jae Ho; Shin, Jung Wook; Kim, Yoon Jun

Abstract

PURPOSE: To investigate the potential of nucleus pulposus (NP) regeneration with a nanofiber-based scaffold inserted in the degenerative disc.
MATERIALS AND METHODS
A nanofiber scaffold was fabricated using an electrospinning technique. In the in-vitro study, a total 18 discs with endplates on both sides were obtained from six New Zealand White (NZW) rabbits. A small volume of NP was removed through the hole from the endplate. The specimens were classified into three groups, intact (normal), inserting nanofiber scaffold (nanofiber), and defect (defect) group. The discs were analyzed by MRI scan and histological analysis. Six NZW rabbits were used in the in-vivo study. An annulotomy was performed through the dorsal approach L2-3 and L3-4 disc. A nanofibrous sheet type scaffold was inserted at L3-4. X-ray, MRI and histology analysis were carried out at 4, 8, 12 weeks after surgery.
RESULTS
In the in-vitro study, the Nanofiber groups showed higher signal intensity and cell proliferation than the defect groups. In the in-vivo study, the Nanofiber and defect groups showed significant degeneration but there was no significant difference between these groups.
CONCLUSION
Nanofiber scaffold might provide a favorable environment for regenerating disc cells. However, a defect in the annulus fibrosus (AF) might delay the regeneration of the disc cell at the nanofiber group. Therefore, NP regeneration using any scaffold should be examined along with AF regeneration for effective clinical applications.