Аннотация:The regeneration of the peripheral nerves after injuries is still a challenging fundamental and clinical problem. In this study, we analyzed the development of the fetal neocortex solid grafts injected into the gelatin hydrogel conduits and their effects on nerve regeneration after cut injury. The study was performed on C57Bl/6 and transgenic heterozygous C57BL/6-Tg(ACTB-EGFP) 1Osb/J mice. Frontal neocortex tissue was obtained from E19.5 fetuses harvested from transgenic EGFP mice. The grafts were injected into the hydrogel conduits which were connected the nerve stumps after cut injury. The recovery of motor function was estimated with walking track analysis at 2, 5, and 8 weeks after surgery. Then immunohistochemical study was performed. Eight weeks after surgery, the histological examination showed that fetal neocortex solid graft cells had survived after implantation. Immunostaining revealed that some of the transplanted cells expressed neural markers such as neurofilament protein and NeuN, which is normal for mouse brain tissue at stage E19.5. But the cells mostly differentiated in glial lineage, which was confirmed with immunostaining for GFAP and S100b. Additionally we didn‘t find any DCX- and MBP-positive cells. To estimate the motor function recovery the walking-track analysis was performed. There were no differences between the control and experimental groups until 8 weeks after surgery, at which point the neocortex group differed significantly from the control (P < 0.05). The sham group was significantly different from the other groups throughout the experiment (P < 0.0001). We revealed that the hydrogel conduit is suitable for nerve re-growth and that the fetal neocortex grafted cells can survive, differentiate, and stimulate functional recovery after the nerve injury. This research was funded by the IDB RAS government program of basic research “Development of a new biomedical technology for the treatment of peripheral nerve injury”.