The Effect Of Downregulation Of SDF-1α /CXVR4 Axis On The Transplantated MSCS’ Homing In The Premature Brain Damage Model

Objective Isolation and culture bone marrow mesenchymal stem cells (BMSCs) derived from Sprague-Dawley rats, and then use the identified and continuable cell resource for further experiments. To investigate how does SDF-la/CXCR4 axis effect BMSCs migration efficiency under different doses in vitro study, and through the infection of lentivrius to knockdown the expression of CXCR4, to compare and discover the efficacy and efficiency of transpanted treated or not treated BMSCs in hypoxic-ischemic preterm brain and trace their migration route.Methods To isolate, culture and identify BMSCs applying tissue adherent culture method. In vitro, to do transwell experiment to observe the efficiency of BMSCs in normoxic and hypoxic condition, under different dose of SDF-la (0、50、100) ng/ml and then inhibited by AMD3100 (5 ug/ml); Intraventricularly injected BMSCs treated by lentivirus or not, to discover the route and efficiency of migration through immunofluorescence.Results The morphology, flow cytometry and transdifferentiation experiments showed BMSCs using tissue adherent culture method is reliable, the cultured third passage fusiformal BMSCs appeared as shuttle, and the monolayer cells growed as helix shape, flow cytometry showed BMSCs positively presented phenotype CD90 (93.1%)、CD29 (99.8%), and negatively presented CD49d 9 (0.45%), CD45 (0.17%). And BMSCs could be transdifferentiated into fat, bone and cartilage; The morphology, flow cytometry showed BMSCs infected by lentivirus retained stem cell characteristics, the best MOI to infect BSMCs was 30, both Western blotting and real time PCR confirmed the targert gene CXCR4 low expression after infection by virus; the migration route of BMSCs under hypoxic-ischemic status were distributed near the lateral ventricular SVZ in first 2 days and then them migrated to hippocampus zone mainly in CA1/CA2 3 days later, and seldom cells were found in cortical zone at 7 days. When the axis was knockdown, cells could only survived in brain 3 days, and limited nearby lateral ventricular.Conclusion The efficacy of migration of BMSCs decreases sharply when down regulated SDF-la/CXCR4, which means SDF-1α/CXCR4 plays an important and irreplaceable role of BMSCs in the premature brain damage model.