DEVELOPMENT OF THERAPY FOR HEPATITIS C USING PROTEIN TRANSDUCTION METHOD

点击翻译按钮获取中文摘要

Although interferon (IFN) therapy can eradicate hepatitis C virus (HCV) from chronic hepatitis C patients, the eradication rate, to date, is only 30%, which is not satisfactory. The most serious impediment in achieving eradication of HCV from patients lies in the difficulty to clear residual HCV in hepatocytes, or to eliminate HCV-infected hepatocytes.To provide a novel method for eradicating HCV from patients, we conducted to establish an experimental system that utilizes the protein-transducting-domain (ptd) of the TAT protein from human immunodeficiency virus. Fusion proteins with the ptd can be distributed to all organs upon the injection of the proteins into the peritoneal cavity. By arranging the Caspase 3 protease subunits p17 and p12 intervened by the recognition sequences of HCV protease that is coded by the NS3 domain of HCV genome, we produced an efficient method to kill only hepatocytes infected with HCV ; HCV-infected hepatocytes possess the HCV protease that activates the Caspase 3, leading the hepatocytes into suicide.By introducing the plasmid pTAT-Casp3-NS3pcs, which encodes the ptd-Caspase3 p17-NS3 cleavage site-p12-NS3 cleavage site, with an expression vector of HCV NS3 protease, HepG2 cells underwent apoptosis.On the other hand, we established transgenic mouse lines carrying the cDNA for HCV NS2-NS5. mRNA transcribed from the NS2-NS5B genes was detected in the mouse liver. Using these mice, an experiment is underway of injecting the protein purified from baculovirus transfected with pTAT-Casp3-NS3pcs.