[Epitope mapping of antigenic determinants of hepatitis C virus proteins by phage display]

Study of individual hepatitis C (HCV) proteins could help to find a molecular structure and conformation, localization of antigenic and immunogenic determinants, to reveal of protective epitopes. It is necessary for practical medicine - development of diagnostic test-systems, vaccines and therapeutics. Linear and conformation dependent epitopes of HCV proteins was localized in this work and immunogenic properties of phage displayed peptides screened on monoclonal antibodies to HCV proteins have been investigated. Eleven epitopes of four HCV proteins have been studied. Three epitopes was found as linear, two epitopes were dependent on secondary structure of proteins and one epitope was dependent on tertiary structure of NS3 protein. Aminoacid sequences of other determinants have been determined and the distinct localization of these determinants will be continued after discovering of tertiary structure of HCV proteins. It was shown, that phage mimotope 3f4 is immunogenic and could induce specific hu- moral immune response to NS5A HCV protein. The data obtained could be useful for improving of HCV diagnostic test-systems, studying of amino acid substitutions and its influence on antigenic properties of the HCV proteins. The results could help to study an immune response in patients infected with different genotypes of HCV. Phage displayed peptides mimicking the antigenic epitopes of HCV proteins could be applied to development of HCV vaccine.