THE PERSPECTIVES OF HEPATITIS-C VACCINE - WHICH STRATEGY TO ADOPT

A high incidence of community-acquired hepatitis C virus infection tha t can lead to the progressive development of chronic active hepatitis, liver cirrhosis and primary hepatocarcinoma occurs throughout the wor ld. Even if the important advances in the development of clinical diag nostic tests have improved the safety of blood transfusion, 50% of car riers result from an unknown mode of transmission, and a vaccine is ne eded to control and eliminate HCV. In spite of the progess in molecula r biology of HCV, the biological characteristics of the virus remain o bscure. Basic studies for a detailed understanding of HCV morphogenesi s and pathogenesis are impeded by the fact that HCV does not replicate appreciably in cell culture systems and that the only well-defined an imal model is the chimpanzee. Another important feature relates to the observed heterogeneity of HCV: at least six genotypes have now been d istinguished from phylogenic analyses. Given this variability, it is v ery likely that a multivalent vaccine will be required for global prot ection, Though recent results on virus neutralization, and vaccination of chimpanzees, offer substancial encouragement and optimism for vacc ine design, further advances in the field of immunological properties of the HCV are awaited.