Expression And Immunogenicity Of Epitopes Of HCV Structural Gene

Hepatitis C virus is the major aetiological agent for non-A,non-B hepatitis.There are 1.7 hundred million infected patients all over the world,and chronic infection is established in about 50%~90% of patients.Researching in epitopes of HCV will help in the development of diagnostic reagent and subunit or recombinant vaccines of HCV.HCV capsid protein is well conserved among different HCV genotypes.N-terminal region of HCV nucleocapsid is highly conserved and a candidate for inclusion in B-cell epitope.The gene of two B-cell epitope C (aa2~21) and C2 (aa33~46) within the immundominant N-terminal region of the HCV nucleocapsid was designed expressed on a chimeric protein with Flock house virus capsid protein as a carrier by inserting in the L1 position of FHV capsid protein encoding gene -RNA2 in E. coli BL21 (DE3).The properties of a given epitope might be influenced by its conformation,FHV carrier system having multiple entry sites conferring many possible comformation closer to the native one for a given sequence.The hybrid protein, representing about 35% of the total cell protein,reacted with antisera of HCV positive patients.Hybrid protein was purified by Q-FF/HP negative ion exchange chromography and SDS-PAGE , immunization of sera-negative guineapig with purified hybrid (fusion)-protein generated antibodies to HCV C protein. FHV foreign epitope presenting system could improve the antigenicity and immunogenicity of HCV C1,. HCV C2 epitope of HCV C protein (p<0.05) .The nucleotide mutation rate in envelope E1 (35%, 152/920) was higher than in core (8%)of HCV. We studied an highly conserved (95.5%) B-cell epitope among different HCV genotypes. We cloned an 410 bp fragement of HCV El, including the encoding gene of B-cell epitope which localized between aa315 and aa328, expressed in E. coli BL21 (DE3) by pET-3a...