(CROSS REACTIVITY OF HYPERVARIABLE REGION 1 (HVR1) EPITOPES AMONG EGYPTIAN PATIENTS INFECTED WITH HCV (TYPE 4

Abstract

We have studied the immune cross reactivity of Hyper variable Region l (1-IYRl) of HCY against HCY immune positive and negative sera. Two published HY R 1 nucleotides consensuses (Italian and Chinese) were synthesized. SOEing PCR, Cloning and sequencing were performed and from the corresponding amino acids sequences, three Italian, one Chinese 1-lYRl peptides were selected for synthesis. Also, seven published Egyptian HYRl peptides and one peptide from HCY core region were synthesized. The twelve peptides (coded MB1-MB12) were used to screen 47 and 31 HCY (Type 4) immune positive and negative sera, respectively in ELISA. The seven Egyptian 1-lYRl peptides (MB4-MB10) have showed reactivities between 42.5%-66%. The three Italian HYRI peptides (MBI- MB2-MB3) have showed reactivities of 83%, 68%, 76.6%, respectively, while the Chinese HYR 1 peptide (MB 11) has showed reactivity of 80. 8%. Screening results of the diagnostic core peptide (PI) in ELISA have showed sensitivity and specificity of 93.6% and 93.5%, respectively. Our results supported that the HYRl is an attractive target for a peptide based vaccine as it contains a neutralizing epitopes and all of the I-ICY patients sera used in this study have anti HYRl antibodies. The considerable reactivities of Egyptian HYRI peptides obtained may be due to the presence of conserved positions containing polar R -base amino acid without charge or due to Schistosomiasis as a socioeconomic health problem associated with HCY infection in Egypt. Interestingly, it was found that the amino acid sequence of peptide MB I have closely related sequence similarity with the published mimotope peptide R9 and it has a high reactivity in ELISA, so it could be used with the core peptide (Pl) as a supplemental test for I-ICY diagnosis.