Abstract
BACKGROUND: Hepatitis C virus (HCV) was found to have a major role in human liver disease by its ability to face the host-cell defenses and the immune system. Heterogeneity of HCV was the key for its adaptation to its host and represented a significant hurdle for the development of both effective vaccines as well as for novel therapeutic interventions. OBJECTIVES: Due to the heterogeneity of HCV virus because of both high replication and high mutation rate in vivo, this study was conducted to analyze different isolates of Egyptian patients of genotype 4, of the most mutant regions of the virus (E1 and E2) as they played an important role in viral persistence by escaping from the immune system of the host body. PATIENTS AND METHODS: This study was conducted through PCR amplification of E1 and E2 regions, sequencing and phylogenetic analysis, calculating synonyms and non-synonyms substitutions, finding the possible glycosylation sites and different epitope domains. RESULTS: The present work figured out that the heterogeneity of the quasispecies of our local strains 4a was high showing up 15% diversity. This study also showed four glycosylation sites that play an important role in the entry of the virus and protein folding. Besides, different epitpoes were identified in different regions of the E1 and E2 domains; a finding which would help in determining the neutralizing and non- neutralizing antibodies. CONCLUSIONS: This study would help in understanding the driving forces of genetic diversity and would be fundamental for representing potential candidate targets for antibodies and the development of vaccine trials.