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Exogenous delivery of nerve growth factor(NGF)promotes neural regeneration.However,the short half-life limits delivery efficacy.Therefore,a long-term,efficient,local delivery tool or scheme is needed.The purpose of this study was to construct a functioning,recombinant,adenoviral vector carrying human NGF-β(hNGF-β)DNA,and to measure expression of the constructed vector in vitro and in vivo.rhNGF-β adenoviral vector containing full-length hNGF-β cDNA was generated by homologous recombination in Escherichia Coli.The rhNGF-β adenovirus was packaged and amplified in human embryonic kidney HEK293 cells.Transformation efficiency,expression and function of rhNGF-β adenovirus for primary Schwann cells,Schwann cell lines,human embryonic kidney HEK 293 cells,CRH myoblasts,and NIH3T3 fibroblasts were evaluated.Subsequently,expression of rhNGF-β adenovirus at the peripheral nerve of rat was also assessed.Recombinant adenoviral vector carrying hNGF-β was successfully constructed and confirmed by restriction endonuclease analysis and DNA sequence analysis.Green fluorescent protein expression was observed in 90% of rhNGF-β adenovirus-infected cells(primary Schwann cells,Schwann cell line,human embryonic kidney HEK 293 cells,CRH myoblasts,and NIH3T3 fibroblasts)compared with non-infected cells.Total mRNA isolated from rhNGF-β adenovirus-infected cells exhibited strong expression.Maximum NGF release was induced by primary cultured Schwann cells at 4 days after infection,which steadily continued for 14 days.PC-12 cells exposed to media conditioned with rhNGF-β adenovirus-infected Schwann cells exhibited increased neurite extension.In vivo experiment revealed that the injected rhNGF-β adenovirus was transfected into the cells at the injected site and promoted expression of NGF,p75NTR and brain derived neurotrophic factor at the sciatic nerve and dorsal root ganglia.