Abstract: Objective To investigate the influence and relative mechannism of stromal cell derived factor 1 (SDF1)secreted by nucleus pulposus cells(NPCs) on the vascularization of degenerated intervertebral disc. Methods NPCs of degenerated intervertebral disc were obtained and cultured. The expression of SDF1 in NPCs was up regulated and down regulated by transfected virus, then NPCs were classified as DOWN(down regulation),D(degeneration) and UP(up regulation) groups according to the expression of SDF1. Human umbilical vein endothelial cells(VECs) were cultured. Different groups of NPCs or conditional medium from NPCs were respectively co-cultured with VECs, during the period, AMD3100, the CXCR4 receptor inhibitor was also added to the co-culture system. The CCK8, cell migration assay and tube formation assay were used to detect the angiogenesis ability of VECs. Result Each group of NPCs was successfully constructed. After co-cultured with VECs, the CCK8, cell migration assay and tube formation assay showed that VECs cell vitality, migration ability and tube formation ability were enhanced as the expression of SDF1 was increased(P<0.05). After adding AMD3100, the cell vitality, migration ability and tube formation ability of VECs were significantly suppressed in D and UP groups(P<0.05). Conclusion SDF1 is secreted by NPCs of degenerated intervertebral disc, the SDF1/CXCR4 axis could influence the ability of vitality, migration and tube formation of VECs, and may play an important role in vascularization of human degenerated intervertebral disc.

Key words: Stromal cell derived factor 1 (SDF1), Nucleus pulposus cells(NPCs), Vascular endothelial cells(VECs), Co-culture