OBJECTIVE: To construct the eukaryotic expression plasmid containing mouse vasoactive intestinal peptide(VIP) gene with biological activities. METHODS: VIP cDNA including the sequences of signal peptide was cloned from mouse thymus by RT-PCR, and then inserted into the mammalian expression vector pcDNA3.1 between Hind III and EcoR I restriction sites. COS-7 cells were transfected with pcDNA3. 1-VIP using liposome, the expression of VIP was identified by Western blot and ELISA. Supernatant of transfected cell culture was added to LPS-stimulated macrophages and the TNF-alpha production in cell medium was observed by ELISA. RESULTS: The cloned VIP cDNA was confirmed by enzyme digestion and DNA sequencing. The expression of VIP was detected in the pcDNA3. 1-VIP transfected COS-7 cells by Western blot and ELISA. The VIP in culture supernatant potently inhibited TNF-alpha production by LPS-induced Macrophages in vitro. CONCLUSION: The eukaryotic expression plasmid that expresses biological active murine VIP has been constructed successfully.
OBJECTIVE: To construct the eukaryotic expression plasmid containing mouse vasoactive intestinal peptide(VIP) gene with biological activities. METHODS: VIP cDNA including the sequences of signal peptide was cloned from mouse thymus by RT-PCR, and then inserted into the mammalian expression vector pcDNA3.1 between Hind III and EcoR I restriction sites. COS-7 cells were transfected with pcDNA3. 1-VIP using liposome, the expression of VIP was identified by Western blot and ELISA. Supernatant of transfected cell culture was added to LPS-stimulated macrophages and the TNF-alpha production in cell medium was observed by ELISA. RESULTS: The cloned VIP cDNA was confirmed by enzyme digestion and DNA sequencing. The expression of VIP was detected in the pcDNA3. 1-VIP transfected COS-7 cells by Western blot and ELISA. The VIP in culture supernatant potently inhibited TNF-alpha production by LPS-induced Macrophages in vitro. CONCLUSION: The eukaryotic expression plasmid that expresses biological active murine VIP has been constructed successfully.