Impact of injury severity on transplantation of embryonic neural stem cells following traumatic brain injury in rats

Abstract

Objective To explore the influence of injury severity on transplantation of embryonic neural stem cells (NSCs) after traumatic brain injury (TBI).Methods The NSCs were isolated from the hippocampus of fetal rats aged at from 12-14 days.The cells were cultured and proliferated in the serum-free medium and identified in vitro.The animals received transplants in the bilateral hippocampal areas at day 3 following mild or moderate TBI separately.Conventional histology,TUNEL and immunohistology were examined to detect BrdU,NSE,GFAP,GalC,NGF and BDNF at day 14 post-implantation.Results BrdU-labeled positive cells in the bilateral hippocampus in the mild TBI group were more than those in the moderate TBI group at day 14 post-implantation.Significant differentiation of the astrocytes recognized as GFAP positive cells in the bilateral hippocampus was found at day 14 post-implantation.The expression of NGF and BDNF proteins was increased following TBI,the most evident in the mild TBI group.Conclusion The influence of injury severity on transplantation may be associated with the change of the microenvironment after TBI. Key words: Brain injuries; Stem cells; Embryo; Rats