*Coculture with Partial Digestion Notochordal Cell-Rich Nucleus Pulposus Tissue Activates Degenerative Human Nucleus Pulposus Cells.
Recent studies suggested that notochordal cells (NCs) and NC-conditioned medium (NCCM) can stimulate cell viability and matrix production of nucleus pulposus cells (NPCs). However, the potential of notochordal cell-rich nucleus pulposus (NRNP) incorporating the native environment of the intervertebral disc (IVD) has not been evaluated. The objective of this study was to develop an optimal NRNP model and test whether it can allow a significant level of NPC activation in vitro. Rabbit NRNP explants were divided into three groups according to different digestion time: digestion NRNP of 8 h, partial digestion NRNP of 2 h, and natural NRNP. Cell viability and NC phenotype were compared between these groups after 14 days of incubation. The products of the selected partial digestion NRNP group were then cocultured with human degenerated NPCs for 14 days. NPC viability, cell proliferation and senescence, the production of glycosaminoglycan (GAG) found in extracellular matrix, and NP matrix production by NPCs were assessed. The results showed that coculturing with partial digestion NRNP significantly improved the cell proliferation, cell senescence, and disc matrix gene expression of NPCs compared with those in the monoculture group. In addition, GAG/DNA ratio in the coculture group increased significantly, while the level of collagen II protein remained unchanged. In this study, we demonstrated that partial digestion NRNP may show a promising potential for NPC regeneration in IVD tissue engineering.
1 Department of Orthopedic Surgery, Navy General Hospital , Beijing, People's Republic of China .
Xue-Dong
XD
Bai
1 Department of Orthopedic Surgery, Navy General Hospital , Beijing, People's Republic of China .|2 Department of Orthopedic Surgery, Gaozhou People's Hospital , Guangdong, People's Republic of China .
Xiao-Chuan
XC
Li
1 Department of Orthopedic Surgery, Navy General Hospital , Beijing, People's Republic of China .
Jia-Hai
JH
Chen
1 Department of Orthopedic Surgery, Navy General Hospital , Beijing, People's Republic of China .
Zi-Ming
ZM
Guo
1 Department of Orthopedic Surgery, Navy General Hospital , Beijing, People's Republic of China .
Li-Sheng
LS
Hou
1 Department of Orthopedic Surgery, Navy General Hospital , Beijing, People's Republic of China .
De-Li
DL
Wang
1 Department of Orthopedic Surgery, Navy General Hospital , Beijing, People's Republic of China .
Qing
Q
He
1 Department of Orthopedic Surgery, Navy General Hospital , Beijing, People's Republic of China .
Di-Ke
DK
Ruan
D000818:Animals; D002452:Cell Count; D049109:Cell Proliferation; D002470:Cell Survival; D002478:Cells, Cultured; D016922:Cellular Senescence; D018920:Coculture Techniques / Q000379:methods*; D004247:DNA / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation; D006025:Glycosaminoglycans / Q000378:metabolism; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009672:Notochord / Q000166:cytology*; D000070614:Nucleus Pulposus / Q000166:cytology*; D010641:Phenotype; D011817:Rabbits
D006025:Glycosaminoglycans; D004247:DNA
cell therapy; coculture; intervertebral disc; notochordal cell-rich nucleus pulposus; nucleus pulposus cells