Experimental observation of human bone marrow mesenchymal stem cell transplantation into rabbit intervertebral discs

Allogeneic bone marrow mesenchymal stem cell (BMSC) transplantation has been investigated worldwide. However, few reports have addressed the survival status of human BMSCs in the intervertebral discs (IVDs) in vivo following transplantation. The current study aimed to observe the survival status of human BMSCs in rabbit IVDs. The IVDs of 15 New Zealand white rabbits were divided into three groups: Punctured blank control group (L1-2); punctured physiological saline control group (L2-3); and punctured human BMSCs transfected with green fluorescent protein (GFP) group (L3-4, L4-5 and L5-6). One, 2, 4, 6 and 8 weeks after transplantation the IVDs were removed and a fluorescence microscope was used to observe the density of GFP-positive human BMSCs. The results indicated that in the sections of specimens removed at 1, 2, 4, 6 and 8 weeks post-transplantation, no GFP-positive cells were observed in the control groups, whereas GFP-positive cells were apparent in the nucleus pulposus at all periods in the GFP-labeled human BMSCs group, and the cell density at 6 and 8 weeks was significantly less than that at 1, 2 and 4 weeks post-transplantation (P<0.001). Thus, it was identified that human BMSCs were able to survive in the rabbit IVDs for 8 weeks.