 End stage HCV-related cirrhosis has become a major indication for liver transplantation LT. Unfortunately, recurrence of HCV infection on the liver graft occurs in almost all patients following transplantation and causes a persistent infection that leads to chronic hepatitis and cirrhosis in a significant proportion of patients. To date there is no effective way to prevent HCV reinfection of the liver graft in the early phase after transplantation. . Early passive immunotherapy with neutralizing antibodies against HCV should be considered for preventing reinfection of liver transplanted patients associated with HCV. This approach is well established in the case of patients undergoing liver transplantation for chronic hepatitis B virus infection. Our purpose is to produce neutralizing monoclonal antibodies to prevent reinfection of the liver graft. 