Generation of HBsAg DNA aptamer using modified cell-based SELEX strategy

Area of Science:

• Biotechnology
• Molecular Biology
• Hepatology

Background:

• Hepatitis B virus (HBV) infection is a major global health concern.
• Hepatitis B surface antigen (HBsAg) is a key serological marker for HBV.
• Aptamers offer potential as alternatives to antibodies for diagnostic and therapeutic applications.

Purpose of the Study:

• To isolate DNA aptamers specific to HBsAg using a modified Cell-SELEX method.
• To evaluate the efficiency and applicability of the modified Cell-SELEX technique.
• To explore the potential of selected aptamers in theranostic applications for HBV.

Main Methods:

• A modified Cell-SELEX (Systematic Evolution of Ligands by Exponential Enrichment) approach was employed.
• HEK293T cells overexpressing HBsAg were used as target cells, with unmodified HEK293T cells as controls.
• Deoxyribonuclease I digestion was utilized to separate single-stranded DNA aptamers against HBsAg.

Main Results:

• Fifteen distinct single-stranded DNA (ssDNA) aptamer clones specific to HBsAg were successfully isolated after six rounds of selection.
• The selected aptamers were clustered into four groups based on shared structural motifs.
• Flow cytometry analysis confirmed the increasing affinity of aptamers with successive selection cycles.

Conclusions:

• The modified Cell-SELEX method is an efficient technique for isolating high-affinity HBsAg-specific aptamers.
• This method potentially reduces selection time and increases success rates while retaining benefits of cell-based SELEX.
• The isolated aptamers hold promise for applications in purification, diagnostics, and drug delivery systems for HBV-related diseases.