High-affinity aptamers to subtype 3a hepatitis C virus polymerase display genotypic specificity

Area of Science:

• Biochemistry
• Virology
• Molecular Biology

Background:

• Hepatitis C Virus (HCV) research often focuses on genotype 1, neglecting other prevalent genotypes.
• High variability in HCV necessitates developing treatments effective against diverse strains.

Purpose of the Study:

• To isolate and characterize DNA aptamers targeting the RNA-dependent RNA polymerase (RdRp) of HCV subtype 3a.
• To evaluate the potential of these aptamers in inhibiting HCV polymerase activity.

Main Methods:

• Systematic Evolution of Ligands by Exponential Enrichment (SELEX) was employed to screen DNA aptamer libraries.
• Biacore 2000 was used for partitioning and selection over ten rounds.
• Binding affinity and polymerase inhibition assays were performed on selected aptamers.

Main Results:

• Two DNA aptamers, r10/43 and r10/47, were identified with high affinity for HCV 3a RdRp (1.3 ± 0.3 nM and 23.5 ± 6.7 nM, respectively).
• Both aptamers demonstrated polymerase inhibition (1.4 ± 2.4 nM and 6.0 ± 2.3 nM).
• Aptamer r10/47 showed specificity for HCV 3a polymerase, while r10/43 had broader activity.

Conclusions:

• This study presents the first specific inhibitor for HCV subtype 3a polymerase.
• The identified aptamers, particularly r10/47, represent promising candidates for developing novel antiviral therapies against HCV genotype 3a.