Surgical removal and controlled trypsinization of the outer annulus fibrosus improves the bioactivity of the nucleus pulposus in a disc bioreactor culture

BMC Musculoskeletal Disorders

Research Article

Rongmao Shi¹  Songtao Li²  Qiang Zhou³  Pei Li³  Yibo Gan³  Lei Song³  Yuan Xu⁴  Daosen Chen⁵ 

[1] Department of Orthopedic Surgery, Kunming General Hospital of Chengdu Command, 650032, Kunming, Yunnan, China;Department of Orthopedic Surgery, No. 181 hospital of PLA, 541002, Guilin, Guangxi, China;Department of Orthopedic Surgery, Southwest Hospital, Third Military Medical University, Gao Tan Yan 29, 400038, Chongqing, China;Department of Orthopedic Surgery, Xinqiao Hospital, Third Military Medical University, 400038, Chongqing, China;The 91245 Troops of the Chinese People’s Liberation Army, 125000, Huludao, Liaoning, China;

关键词: Intervertebral disc;    Degeneration;    Organ culture;    Nucleus pulposus;   

DOI  :  10.1186/s12891-016-0990-2

 received in 2016-01-04, accepted in 2016-03-17,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundThe maintenance of nucleus pulposus (NP) viability in vitro is difficult. The annulus fibrosus (AF) pathway reflects one nutrient transport channel and may have an important effect on NP viability in disc organ cultures. The present study describes a feasible disc pre-treatment involving the AF and investigates its efficacy in improving NP bioactivity in an in vitro disc bioreactor culture.MethodsRabbit discs that were randomly assigned to the experimental group (EG) were pretreated via the surgical removal and controlled trypsinization of the outer AF. The discs in the control group (CG) did not receive any special treatment. All discs were organ-cultured in a self-developed bioreactor. Solute transport into the central NP was measured using a methylene blue solution. On days 7 and 14, histological properties, cell viability, cell membrane damage, gene expression and matrix composition within the NP in these two groups were compared with each other and with the corresponding parameters of fresh NP samples. Additionally, the structures of the outer AF and the cartilage endplate (CEP) following pre-treatment were also assessed.ResultsThe outer AF in the EG became disorganized, but no specific changes occurred in the CEP or the inner AF following pre-treatment. The discs in the EG exhibited increased penetration of methylene blue into the central NP. On days 7 and 14, the NP bioactivity in the EG was improved compared with that of the CG in terms of cell viability, cell membrane damage, gene expression profile and matrix synthesis. Moreover, cell viability and matrix synthesis parameters in the EG were more similar to those of fresh samples than they were to the same parameters in the CG on day 14.ConclusionsUsing this disc pre-treatment, i.e., the surgical removal and controlled trypsinization of the outer AF, NP bioactivity was better maintained for up to 14 days in an in vitro disc bioreactor culture.

【 授权许可】

CC BY   
© Li et al. 2016