title: The effects of human Wharton's jelly cell transplantation on the intervertebral disc in a canine disc degeneration model.
abstract: BACKGROUND
  Cell-based therapy was a promising treatment method for disc degenerative diseases. Wharton's jelly cell (WJC) has been explored to cure various human diseases, while it still remains unknown about this MSC for disc repair. In our prior work, WJCs could differentiate into nucleus pulposus (NP)-like cells by co-culturing with NP cells in vitro. Thence, the aim of this study was further to investigate the survival and function of WJCs in vivo after transplantation into degenerated canine discs.
  
  
  METHODS
  WJCs were isolated from human umbilical cords and labeled with EGFP. The degeneration of L4-5, L5-6, and L6-7 discs of beagles was induced by aspirating the NP tissues. Four weeks after the operation, the injured discs were left to be no treatment at L4-5 (DS group), injected with 0.9 % saline at L5-6 (FS group), and transplanted with EGFP-labeled WJCs at L6-7 (TS group). In all animals, the intact disc L3-4 served as a control (CS group). The animals were followed up for 24 weeks after initial operation. Spine imaging was evaluated at 4, 8, 12, and 24 weeks, respectively. Histologic, biomechanics and gene expression analyses were performed at 24 weeks. Immunohistochemistry for aggrecan, types II collagen, SOX-9 was employed to investigate the matrix formation in the NP.
  
  
  RESULTS
  The TS group showed a significantly smaller reduction in the disc height and T2-weighted signal intensity, and a better spinal segmental stability than DS and FS groups. Histologic assay demonstrated that WJCs were specifically detected in TS group at 24 weeks and the discs of TS group maintained a relatively well preserved structure as compared to the discs of DS and FS groups. Furthermore, real-time PCR and immunohistochemistry demonstrated that expressions of disc matrix genes, aggrecan, type II collagen, and SOX-9, were up-regulated in TS group compared to DS and FS groups.
  
  
  CONCLUSIONS
  WJCs could not only survive in the degenerate IVDs, but also promote the disc matrix formation of aggrecan and type II collagen in the degenerate IVDs. It may have value in cell-based therapy for degenerative disc disease.
authors: Department of Orthopedic Surgery, Navy General Hospital, No. 6 Fu-cheng Road, Beijing, 100048, P R. China. zhangyan0718@163.com.|VIP Neurology Department, Navy General Hospital, No. 6 Fu-cheng Road, Beijing, 100048, P R. China. zhangyan0718@163.com.
authors: Yan
authors: Y
authors: Zhang
authors: Department of Spine Surgery, The First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, Anhui, China. taoh19870131@163.com.
authors: Hui
authors: H
authors: Tao
authors: Department of Orthopedic Surgery, Navy General Hospital, No. 6 Fu-cheng Road, Beijing, 100048, P R. China. gutao0618@163.com.
authors: Tao
authors: T
authors: Gu
authors: Department of Orthopedic Surgery, Navy General Hospital, No. 6 Fu-cheng Road, Beijing, 100048, P R. China. zmy15040496805@163.com.
authors: Mingyue
authors: M
authors: Zhou
authors: Department of Orthopedic Surgery, Navy General Hospital, No. 6 Fu-cheng Road, Beijing, 100048, P R. China. jiazhiweivip@163.com.
authors: Zhiwei
authors: Z
authors: Jia
authors: Department of Orthopedic Surgery, Navy General Hospital, No. 6 Fu-cheng Road, Beijing, 100048, P R. China. Jianggangqiangngh@163.com.
authors: Gangqiang
authors: G
authors: Jiang
authors: Department of Orthopedic Surgery, Navy General Hospital, No. 6 Fu-cheng Road, Beijing, 100048, P R. China. chenchunkk@163.com.
authors: Chun
authors: C
authors: Chen
authors: Department of Orthopedic Surgery, Navy General Hospital, No. 6 Fu-cheng Road, Beijing, 100048, P R. China. hzh209@163.com.
authors: Zhihua
authors: Z
authors: Han
authors: Department of Orthopedic Surgery, Navy General Hospital, No. 6 Fu-cheng Road, Beijing, 100048, P R. China. puhuofeie@126.com.
authors: Cheng
authors: C
authors: Xu
authors: Department of Orthopedic Surgery, Navy General Hospital, No. 6 Fu-cheng Road, Beijing, 100048, P R. China. wangdeli@medmail.com.
authors: Deli
authors: D
authors: Wang
authors: Department of Orthopedic Surgery, Navy General Hospital, No. 6 Fu-cheng Road, Beijing, 100048, P R. China. bjheqing@sina.com.
authors: Qing
authors: Q
authors: He
authors: Department of Orthopedic Surgery, Navy General Hospital, No. 6 Fu-cheng Road, Beijing, 100048, P R. China. Ruandikengh@163.com.
authors: Dike
authors: D
authors: Ruan
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004285:Dogs; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D007403:Intervertebral Disc / Q000166:cytology*; D055959:Intervertebral Disc Degeneration / Q000378:metabolism* / Q000628:therapy*; D008279:Magnetic Resonance Imaging; D059631:Wharton Jelly / Q000166:cytology*