Abdelhafez Tawfeek H, Bader El Din Noha G, Tabll Ashraf A, Mashaly Mohammad M, Dawood Reham M, Yassin Nemat A, El-Awady Mostafa K
1 Department of Microbial Biotechnology, National Research Center , Dokki, Giza, Egypt .
2 Department of Chemistry, Faculty of Science, Damietta University , Damietta, Egypt .
Viral Immunol. 2017 Jun;30(5):359-365. doi: 10.1089/vim.2016.0123. Epub 2017 Apr 12.
Synthetic peptides are one of the hepatitis C virus (HCV)-specific small molecules that have antiviral activity and represent a target for HCV vaccine. This study aims to determine the lowest concentration of adjuvanted and non-adjuvanted (multiple antigenic peptide [MAP]) form of three conserved HCV envelope peptides that can induce murine immunogenic responses and evaluate the neutralization capacities of the generated antibodies (Abs) against HCV in cultured Huh7.5 cells. In this study, three HCV synthetic peptides, E1 peptide (a.a 315-323) and E2 peptides (a.a 412-419 and a.a 516-531) were synthesized. Female Balb/c mice were immunized with different concentration of either adjuvanted linear peptides or nonadjuvanted MAP peptides to determine the lowest dose that generates Ab responses enough to confer viral neutralization in vitro. The humoral responses targeting these peptides in immunized mice sera were measured by enzyme-linked immunosorbent assay (ELISA). Viral neutralization capacities of the generated mice Abs were assessed using Huh7.5 cells infected with the HCVcc infectious system (J6/JFH-1). The results of this study showed that the MAPs induce higher Ab titers than adjuvanted linear peptides after 4 weeks of immunization (p = 0.003). The viral neutralization experiments showed that the immunized mice sera contain anti E1/E2 Abs that blocked HCVcc (J6/JFH-1) entry into Huh7.5 cells. In conclusion, the three HCV envelope MAP peptides are more immunogenic and produce higher neutralizing Abs than linear peptides; therefore, they can be essential components for HCV vaccine.
合成肽是丙型肝炎病毒（HCV）特异性小分子之一，具有抗病毒活性，是HCV疫苗的一个靶点。本研究旨在确定三种保守的HCV包膜肽的佐剂形式和非佐剂形式（多抗原肽[MAP]）能够诱导小鼠免疫反应的最低浓度，并评估在培养的Huh7.5细胞中所产生抗体（Abs）对HCV的中和能力。在本研究中，合成了三种HCV合成肽，即E1肽（氨基酸315 - 323）和E2肽（氨基酸412 - 419和氨基酸516 - 531）。用不同浓度的佐剂线性肽或非佐剂MAP肽免疫雌性Balb/c小鼠，以确定产生足以在体外赋予病毒中和能力的抗体反应的最低剂量。通过酶联免疫吸附测定（ELISA）测量免疫小鼠血清中针对这些肽的体液反应。使用感染HCVcc感染系统（J6/JFH - 1）的Huh7.5细胞评估所产生的小鼠抗体的病毒中和能力。本研究结果表明，免疫4周后，MAP诱导的抗体滴度高于佐剂线性肽（p = 0.003）。病毒中和实验表明，免疫小鼠血清中含有可阻断HCVcc（J6/JFH - 1）进入Huh7.5细胞的抗E1/E2抗体。总之，三种HCV包膜MAP肽比线性肽具有更强的免疫原性，能产生更高的中和抗体；因此，它们可能是HCV疫苗的重要组成部分。
