High-resolution 3D printing of angle-ply annulus fibrosus scaffolds for intervertebral disc regeneration

Zhao Liu; Huan Wang; Zhangqin Yuan; Qiang Wei; Fengxuan Han; Song Chen; Hao Xu; Jiaying Li; Jiayuan Wang; Zexi Li; Qixin Chen; Jerry Fuh; Lin Ding; Hui Wang; Bin Li

doi:10.1088/1758-5090/aca71f

High-resolution 3D printing of angle-ply annulus fibrosus scaffolds for intervertebral disc regeneration

Biofabrication. 2022 Dec 15;15(1). doi: 10.1088/1758-5090/aca71f.

Authors

Zhao Liu^{1

2}, Huan Wang¹, Zhangqin Yuan¹, Qiang Wei¹, Fengxuan Han¹, Song Chen¹, Hao Xu¹, Jiaying Li¹, Jiayuan Wang¹, Zexi Li¹, Qixin Chen¹, Jerry Fuh^{3

4}, Lin Ding⁵, Hui Wang³, Bin Li¹

Affiliations

¹ Department of Orthopedic Surgery, Orthopedic Institute, The First Affiliated Hospital, Suzhou Medical College, Soochow University, Suzhou, People's Republic of China.
² State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai, People's Republic of China.
³ National University of Singapore Suzhou Research Institute, Suzhou, People's Republic of China.
⁴ National University of Singapore, Centre for Additive Manufacturing, Singapore.
⁵ New Rural Development Research Institute of Northwest Normal University, Northwest Normal University, Lanzhou, People's Republic of China.

PMID: 36541475
DOI: 10.1088/1758-5090/aca71f

Abstract

Intervertebral disc (IVD) degeneration is one of the leading causes of disability, and current therapies are mainly unsatisfactory. The key pathological feature during IVD degeneration is the dysfunction of annulus fibrosus (AF). Although tissue-engineered AF has shown great promise for IVD regeneration, the design and fabrication of biomimetic AF scaffold remains a challenge due to the complexity of its structure. Nowadays, 3D printing technology has drawn great attention due to its customizable processes and ability to produce complex tissue architecture. However, few existing 3D printing methods can accurately replicate the fine angle-ply architecture of native AF, which is one of the most critical steps for IVD regeneration, due to the limited printing resolution. In this study, we aimed to fabricate high-resolution polycaprolactone (PCL) scaffolds using a newly developed electrohydrodynamic 3D printing technique. The structural advantages of such scaffolds were verified by finite element analysis (FEA). The PCL scaffolds were further assembled into AF construct to replicate the angle-ply architecture of AF. The optimal assembling method was confirmed by FEA and mechanical tests. Thein vitroexperiments showed that the 3D printed AF scaffolds presented favorable biocompatibility and supported the adhesion and growth of AF cells. Thein vivoperformance of tissue-engineered IVDs (TE-IVDs), which consisted of 3D printed AF scaffold and GelMA hydrogel that simulated nucleus pulposus (NP), were evaluated using a rat total disc replacement model. We found that the implantation of TE-IVDs helped maintain the disc height, reduced the loss of NP water content, and partially restored the biomechanical function of IVD. In addition, the TE-IVDs achieved well integration with adjacent tissues and promoted new tissue formation. In summary, being able to accurately simulate the structural characteristics of native AF, the 3D printed angle-ply AF scaffolds hold potential for future applications in IVD regeneration.

Keywords: disc replacement; electrohydrodynamic 3D printing; finite element analysis; intervertebral disc; tissue engineering.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Annulus Fibrosus*
Intervertebral Disc*
Printing, Three-Dimensional
Rats
Regeneration
Tissue Engineering / methods
Tissue Scaffolds / chemistry