Aim:To investigate the transfection feasibility of TNF-related apoptosis-inducing ligand (TRAIL) gene into neural stem cells (NSCs) in vitro, and explore whether NSCs retain the proliferative and differentiated activities after transfection.Material and Methods:NSCs were obtained from brains of fetal mice, cultured with serum-free medium and identified by immunofluorescence staining. Lentivirus vector solution containing green fluorescent protein (GFP) gene was added to the NSCs according to the multiplicity of infection (MOI). The transfection efficiency of GFP was observed using a fluorescence microscope and detected by flow cytometry. NSCs were transfected with GFP-TRAIL fusion genes mediated by the optimized MOI lentivirus solution. The expression of TRAIL proteins in NSCs was detected by immunofluorescence and Western-blot analysis. The differentiation of NSCs were induced and identified by immunofluorescence staining.Results:The optimal MOI value of virus transfection was 10, and the transfection rate was higher than 90%. GFP fluorescence could be observed at 24 hours after GFP-TRAIL genes transfected into NSCs with MOI 10, and reached the maximum value at 72 hours. It was confirmed by immunofluorescence and Western-blot assay that GFP-TRAIL fusion proteins could be expressed continuously and stably. The transfected NSCs could differentiate into neurons and glial cells, and no statistical difference was found compared with the non-transfected group.Conclusion:Neural stem cells possessed proliferative and differentiated potential after transfected with TRAIL gene, and could express TRAIL protein sustainably.