ObjectiveTo investigate target gene therapy for hepatocellular carcinoma (HCC). MethodsHerpes simplex virus thymidine kinase (HSVTK) gene was inserted into the gene of AFP enhancer/ALB promoter with adenoassociated virus (AAV) plasmid (WAV2) as a carrier, and a hybrid plasmid pWAV2/AFPALB/HYTK was constructed. Besides, plasmid pEGFP1/AFPALB was also constructed. Two kinds of plasmids were transferred into AFP positive cells HepG2 and AFP negative cells 7721, SPC and 7901.ResultsIt was found that enhance green fluorescence protein could only be seen in AFP positive cells HepG2. 710 bp DNA was amplified only in AFP positive HepG2 cells.ConclusionPlasmid pWAV2/AFPALB/HYTK for HCC demonstrates specificity in vitro.
Objective To construct the recombinant adeno-associated virus vector with human bone morphogenetic protein 4 gene（AAV-hBMP4）. Methods The hBMP-4 gene primer was designed basing on the corresponding gene sequence in GenBank. EcoR I site was introduced into the upstream of the primer and Sal Ⅰ site into downstream. The hBMP-4 gene was amplifiedwith the template of EX-A0242-M01-hBMP-4, then was cloned into pUC18 vectorto construct recombinant plasmid pUC18-hBMP-4. The plasmids pUC18-hBMP-4 and plasmid pSNAV cut by EcoR Ⅰ and Sal Ⅰenzyme, the fragments were collected and linked with T4 DNA ligase at 16℃ over night, recombinant plasmid pSNAVhBMP-4 was obtained. The recombinant plasmid was then transfected into BHK21 cells using Lipofectamine TM2000. The G418 resistant cells were obtained consequently. Thesecells were infected with HSV1-rc/△UL2 which has the function of packaging andcopying the recombinant AAV. After purification, the construction of recombinant AAV-hBMP-4 was completed. Results The construction of the recombinant pSNAV-hBMP-4 was confirmed by PCR electrophoresis and digestion with restriction enzyme. The gene sequence in the recombinant pSNAV-hBMP-4 wascorrect. The virus titer was about 1.5×1012 μg/ml.The purity of the virus was more than 95% using the SDSPAGE method. Conclusion With this method, high virus titers and purity of AAV-hBMP-4 can be acquired successfully and it is useful to bone tissue engineering.