Bone marrow mesenchymal stem cells co-culture and in vivo transplantation inhibit degeneration of intervertebral disc in rabbits

Intervertebral disc degeneration (IDD) is featured with decreased content of proteoglycan and type II collagen in disc nucleus and dehydration. Recent progress of tissue engineer provides novel measures for treating IDD. Bone marrow mesenchymal stem cells (MSCs) are a family of pluripotent cells with differentiation, replication and proliferation abilities. Under certain conditions, MSCs can differentiate into osteoblasts, chondrocytes and endothelial cells. This study explored the co-culture and transplantation of MSCs and notochord cells, on a rabbit IDD model. New Zealand rabbits were collected for notochord cells and MSCs, both of which were co-cultured at different ratios. CCK8 assay was used to detect the cell proliferation, while real-time fluorescent PCR and Western blotting were used to describe phenotypes of MSCs. Transplantation of co-cultured cells were then performed to detect the change of IDD. Under 50:50 ratio, co-cultured cells had higher proliferation and elevated type II collagen expression than singly cultured cell. Those rabbits received co-cultured cell transplantation had significantly elevated expression of type II collagen compared to notochord cells, whilst singly transplanted MSCs had no significant effects. 50:50 co-culture of notochord cells and MSCs causes strongest cell proliferation ability. The transplantation of co-cultured cells may inhibit the progression of IDD in rabbit models.