To investigate the potential use of synthetic stabilized ribozymes for the treatment of chronic hepatitis C virus (HCV) infection,we designed and synthesized 2 hammerhead ribozymes (Rz213 and Rz498) targeting conserved sites in the 5′noncoding region (NCR) and C gene of HCV RNA.Constructed to the eukaryotic vector pcDNA3, the two ribozymes were respectively or simultaneously transfected with lipofectamine into WISHnc transgenic cells, which could express permanently HCV C luciferase protein under the control of HCV 5′NCR.The expression of C luciferase was measured by luminometer.The results showed that the luciferase activities were significantly down regulated in the WISHnc cells, and the inhibitory rates were 42.94%～67.81% within 7 days after ribozymes transfection. There was no significant differences between Rz213 or Rz498 and co transfection, but adding the target site of ribozymes might prevent host cells from the loss of ribozyme therapeutic effect due to viral gene mutation.

Objective To detect hepatitis C virus core antigen in 7721 cells transfected with HCV cDNA by immunohistochemistry method with human single chain Fv antibody(scFv). Methods The recombinant phages were panned by core antigen which was coated in a microtiter plate. After three rounds of biopanning, 48 clones were identified specific to core antigen. The affinity and specificity of scFv were evaluated by ELISA and immunohistochemistry. Results ScFv-core DNA digestion and sequence data showed that the scFv gene was composed of 774bp. Conclusion Human single chain Fv antibody against HCV core antigen has a specific combining capacity with hepatitis C virus core antigen.