Repair Of Peripheral Nerve Defects After Co-culture Of S100? Gene-modified Olfactory Ensheathing Cells With ANX

Objective To investigate the repair effect of S100? gene-infected olfactory ensheathing cells(OECs)co-culture with acellular nerve xenografts(ANX)on rat sciatic nerve injury.Methods 1.Olfactory ensheathing cells derived from olfactory bulb of SD rats were cultured by differential adherence combined with trypsin digestion.The olfactory ensheathing cells were infected with lentivirus expressing S100?gene and the proliferation of transfected cells was detected.2.Decellularization of New Zealand white rabbit-derived nerve scaffolds by chemical extraction and detection of decellularization.3.Establish a model of sciatic nerve injury in SD rats completely disconnected from 8 mm,using heterogeneous neural bridges,heterogeneous neural bridges of olfactory ensheathing cells transfected with empty vector,and heterogeneous neural bridges of olfactory ensheathing cells transfected with S100?bridge damage of rats sciatic nerve of two end namely ANX group(group A),GFP-OECs + ANX group(group B),and according to S100?-OECs + ANX group(group C),4 w and 8 w two time points to evaluate the effect of repairing peripheral nerve defect.Results 1.The purity of olfactory ensheathing cells obtained by differential adherence combined with limited time trypsin digestion was(96.13±0.01)%.2.The heterogeneous neural bridge obtained by chemical extraction completely removes the structure of cells and myelin sheath,only retains the basement membrane component.At 4w after operation,compared with group A and groupB,the recovery of sciatic nerve function index,climbing slope,limb retraction time and other factors such as wet weight of tibialis anterior muscle in group C were better(P<0.05).However,no significant difference was found between the electrophysiological results and the wet weight ratio of the gastrocnemius muscle(P>0.05),and there was no statistical difference between the A and B groups.Histologically,the internal structure of the bridging bodies in group B and C was mostly cellular,while the vascular structure was almost all in group A.In the 8w,The sciatic nerve function index,uphill slope,limb retraction time,incubation period and conduction velocity indexes in group C were better than A and B(P<0.05),wet weight ratio of the tibialis anterior muscle and gastrocnemius wet weight ratio index is better than that of group A,B and only have statistically significant with group A(P<0.05),Compared between group A and group B,each index of group B was better than that of group A in numerical value,but there were statistical differences only in sciatic nerve function index,limb retraction time,and wet weight ratio of gastrocnemius muscle(P<0.05).Histologically,the number of regenerated myelin in group B and group C was more than that in group A,and the shape of myelin was more regular.Conclusion In this experiment,the S100? overexpressing cell system was obtained by infecting OECs with S100? lentivirus,and the cell system has good compatibility with ANX.After co-culture,after co-culture of cells and scaffolds,NGF,BDNF and other factors that promote nerve regeneration can be secreted.The results of this study confirmed that ANX loaded with S100?-OECs can be used as an ideal material for injury and repair experiments of rat sciatic nerve and its repair effect is good.