The Effects Of FTY720on Lymphocytes After Acute Spinal Cord Injury In Rats

Objective:The aim of this study is to investigate the immunological andinflammatory mechanisms after the treatment of acute spinal cord injury (ASCI) by anew immunosuppressant FTY720. The neuroprotective effects of FTY720on ASCIwere explored through the observation of the changes of the peripheral blood andtopical spinal cord injury lymphocytes, through the observation of the motor neuralfunctional recovery.The treatment mechanisms of FTY720for the ASCI in rats wereexplored.Methods: To establish the ASCI model of rats, the rats were divided into fiverandom groups: Group A: normal control group; Group B: sham group; Group C: spinalcord injury group; Group D: FTY720systemic treatment after surgery and Group E:FTY720topical treatment after surgery. Tissue samples were obtained after behaviorobservation in group A.Tissue samples were obtained from group B,C,D,E atpostoperative12h,48h,72h and1wk when the tissue samples were used forlymphocytes counts, HE staining and IHC.To observe the changes of lymphocytes inperipheral blood and spinal cord tissue after surgery by flow cytometry.To observe themotor neural functional recovery by BBB scales.To observe the pathological changes ofthe spinal cord tissue by HE staining.To observe the expression changes of GFAP byimmunohistochemistry.The results were analyzed by Image-pro plus6.0and SPSSsoftware18.0.Results: The motor neural functional recovery after ASCI in rats through theadministration of FTY720can be observed by BBB score results,HE staining andImmunohistochemistry of GFAP,the neuroprotective capacity of topical administration is superior to systemic administration.In peripheral blood,the CD3,CD4,CD4/CD8ratiowas lower in Group C than Group B at all time points. CD3, CD4, CD8, CD4/CD8ratioin Group D was decreased significantly as compared to Group C. Range of values ofGroup E was between the level of peripheral blood lymphocytes in Group C and GroupD.In topical spinal cord tissue,the CD3, CD4, CD8, CD4/CD8ratio in Group C washigher than Group B. CD3, CD4, CD8, CD4/CD8ratio in Group E weresignificantly lower than Group C after application of FTY720. The range of all scores ofGroup D was between Group C and Group E.Conclusions: The motor neural functional recovery after ASCI in rats can beachieved through the administration of FTY720;The topical infiltration of lymphocytescan be decreased after ASCI in rats through the administration of FTY720;The sideeffects of reduction of peripheral blood lymphocyte counts and the body’s immunefunction can be found in systemic administration of FTY720;The side effects ofsystemic administration can be reduced by topical administration of FTY720and theneuroprotective capacity of topical administration is superior to systemicadministration.