The Experimental Study On Orient Immigration Of Mesenchymal Stem Cells Transfected By CXCR-4 Gene After Intravenous Transplantation In Mice With Spinal Cord Injury

Objectives:(1) Isolate,culture,identificate and mark BMSCs with GFP gene.(2) Establish the models of Mice' T10 spinal cord injury,and treat them through BMSCs transplantation.(3) Investigate the orient immigration of BMSCs in the parts of injured spinal cord examine the regenerative function of spinal cord.Methods:(1) BMSCs were harvested from bone marrow of C57BL/6 mice by density centrifugation and identified through osteoblastic and adipogenic induction,the cells were tested CD44 and CD34 by flow cytometry.Mark BMSCs with GFP gene by adenovirus vector. (2) Mice were subjected to spinal cord crosscut injury.Mice of experimental group were intravenous injected by the Suspensions Of neural-like BMSCs transfected by CXCR-4 gene. Mice of the control group were respectively intravenous injected by the suspensions of n0n-transfected BMSCs and non-cell culture medium.(3) Detect the proportion of GFP positive cells to all cells in different site after transplantation with laser scanning confocal microscope and detect the proportion of neural-like cells differentiated from BMSCs to all the transplanted cells with immunohistochemistry.Detected the ability of spinal cord repairing and orient immigration,of neural-like BMSCs transfected by CXCR-4 gene in vivo.Evaluate the recovery condition of psychomotor function by BBB locomotor rating scale.Results:(1) BMSCs grew as clony-like manner,expressed calcium deposition after induction by osteoblastic culture medium and formed fat droplets in adipogenic culture medium.About 80%BMSCs transfected with GFP gene expressed GFP positive.The morphological changes of BMSCs also appeared and expressed NSE positive after neural induction.(2) Most of the mice became paraplegia after spinal cord crosscut(BBB＜4).Mice of randomized grouping were successfully intravenous injected by the certain suspensions 7 days post-operation.(3) At the each day after transplantation,we detected the number of GFP positive BMSCs in the injured part of spinal cord in experimental group gradually increased, and the increasing range were obviously superior to those of the controlled group without transfection.More BMSCs in experimental group differentiated into neural-like cells and the psychomotor function of Mice have significantly recovered. Conclusions:(1) BMSCs could be harvested from bone marrow of mice C57BL/6 by density centrifugation,and realized the induced differentiation to neural-like cells in vitro.(2) The models of Mice' spinal cord injury could be successfully established and perform stem cells transplantation through intravenous injected.(3)The ability of the orient immigration of neural-like BMSCs transfected by CXCR-4 gene is obviously superior to those of the controlled group without transfection and play an important role in the healing process of the spinal cord injury.