Co-transplantation Of CD34~+ Cells And Schwann Cells Improves The Recovery Of Function In Hind Limbs Of Rats Subjected To Spinal Cord Transected Injury And Thire Differentiation And Survival

Objective:To explore the engrafted effect of CD34⁺ cells and Schwann cells on the recovery of function in hind limbs of rats subjected to spinal cord transected injury and to observe the cells differentiation and survival in the transplantation.Methods:â‘ sixty clean-grade SD adult rats were randomly divided into 5 groups with 12 animals in each group:CD34⁺ cells group,SCs group and co-transplantation group,control group as well as control group with ciclosporin injection.Two clean-grade ICR mouse aged 6～8 weeks were selected to culture the CD34⁺ cells.Thirty ICR new born mouse aged 1～2 days were selected to culture the Schwann cells.2 weeks after spinal cord transected injury(spinal cord was transplanted between T9～T10 segments),the cells cultured in vitro were injected in the scar and a segment of the scar up and down through multi-point injection(6×10⁵/per in CD34⁺ cells group,1.2×10⁶/per in co-transplantation group).And then,ciclosporin was used after transplantation.Respectively at the 1^th～12^th,16^th,20^th,24^th weeks,the locomotor functions of rats were detected by BBB score.The mechanical withdrawal threshold was measured by Dynamic Planter Aesthesiometer(Ugo Basile,Italy) and the thermal withdrawal threshold was measured by Hargreaves Test(Ugo Basile,Italy).This was followed by a histochemical observation to know the engrafted cells survival,migration and differentiation.â‘¡To evaluate the motor and sensory function of rats in every time-point,and observe the cells survival,migration and differentiation in those transplantation.Results:â‘ Motor function:In 3 months after transplantation,CD34⁺ cells group was better than others,the later,co-transplantation was more effective than CD34⁺ cells group.â‘¡Sensory function:The recovery of withdrawal threshold was much better than thermal withdrawal threshold.Each groups were found a law that increasing with time and the withdrawal threshold gradually improved,but that was not found in the thermal withdrawal threshold.â‘¢Survival:CD34⁺ cells had a higher fraction surviving in the co-transplantation,especially in the 3^rd month.â‘£Migration:CD34⁺ cells had a different levels of migration.⑤Differentiation: Neu-N and GFAP were showed co-transplantation had a higher differentiation rate than single transplantation.O4 was found that increasing with time,reducing the rate of differentiation.APC was opposite of the change.â‘¥SCs phenotype changes:The expression of GFAP of Schwann cells was gradually increased in 3 months.Conclusion:1,To improve the recovery of function in hind limbs of rats subjected to spinal cord transected injury,co-transplantation of CD34⁺ cells and Schwann cells is more effective than CD34⁺ cells transplanted.2,CD34 cells transplanted in the injury site could be long-term survival,migration and differentiate to neuron-like and glial cell-like cells.3,Schwann cells gradually increased the expression of GFAP in transplantation.