Inhibition of Hepatitis C Virus Production by Aptamers against the Core Protein

Abstract

bHepatitis C virus (HCV) core protein is essential for virus assembly. HCV core protein was expressed and purified. Aptamers against core protein were raised through the selective evolution of ligands by the exponential enrichment approach. Detection of HCV infection by core aptamers and the antiviral activities of aptamers were characterized. The mechanism of their anti-HCV activity was determined. The data showed that selected aptamers against core specifically recognize the recombinant core protein but also can detect serum samples from hepatitis C patients. Aptamers have no effect on HCV RNA replication in the infectious cell culture system. However, the aptamers inhibit the production of infectious virus particles. Beta interferon (IFN-␤) and interferon-stimulated genes (ISGs) are not induced in virally infected hepatocytes by aptamers. Domains I and II of core protein are involved in the inhibition of infectious virus production by the aptamers. V31A within core is the major resistance mutation identified. Further study shows that the aptamers disrupt the localization of core with lipid droplets and NS5A and perturb the association of core protein with viral RNA. The data suggest that aptamers against HCV core protein inhibit infectious virus production by disrupting the localization of core with lipid droplets and NS5A and preventing the association of core protein with viral RNA. The aptamers for core protein may be used to understand the mechanisms of virus assembly. Core-specific aptamers may hold promise for development as early diagnostic reagents and potential therapeutic agents for chronic hepatitis C.

Use of Aptamers as Diagnostics Tools and Antiviral Agents for Human Viruses

“…Afterwards, Shi et al developed a similar platform for early detection, coating the bottom of the well with C7, a DNA aptamer against HCV core labelled with biotin, and HCV-core antibody conjugated with horseradish peroxidase (HRP) is applied over the surface. The platform was applied to the detection of the protein in sera from HCV-infected patients and showed a proportional relationship between amplified RNA copies and HCV core protein concentration [82]. Moreover, Wang et al designed a rapid, easy-to-use diagnostic platform composed of lateral flow strips treated with thiol-DNA aptamers against HCV core antigen.…”

“…In the case of core, an essential protein for HCV viral assembly, Shi et al have applied for therapy the above-mentioned aptamers in diagnostics. In Huh7.5 cells, the aptamers against HCV core protein repressed viral production as a result of defective assembly of virus particle without stimulation of innate immune response [82]. …”

Characterization of a Novel Specific Mouse Monoclonal Antibody Targeted to Envelope Protein E1/E2 of Hepatitis C Virus

“…The high sensitivity was detected till 2.00 µg/ml of the coated antigen. Several mouse monoclonal antibodies targeting HCV core and envelope regions are already known and these antibodies are mainly used for antigen detection (Cagnon et al, 2004, Tabll et al, 2008and Shi et al, 2014.The monoclonal antibody (7G9) is targeted to the envelope glycoproteins E1 and E2.These envelope glycoproteins E1 and E2 are essential in the attachment and entry of the virus ( Sabo et al ,2011).E2 causes not only viral attachment to the cell membrane at its entrance but enhances also the neutralizing antibodies in the host. The envelope proteins play a major role in attachment and entry of virions into the body (Mazumdar et al, 2011) and (Park et al, 2013).…”

Oligonucleotide aptamers: promising and powerful diagnostic and therapeutic tools for infectious diseases

“…Other research groups reported aptamers against HCV core (C) antigen for HCV detection. [109][110][111] Ghanbari et al immobilized an anti-C antigen aptamer onto graphene quantum dots (GOD), and the aptamer-GOD was placed on the surface of a glassy carbon electrode. 111 They demonstrated that the electrochemical aptamer-based biosensor effectively detects the HCV C antigen with the detection limit of 3.3 pg/mL.…”