Occludin-binding single-chain variable fragment and antigen-binding fragment antibodies prevent hepatitis C virus...

Area of Science:

• Virology
• Immunology
• Molecular Biology

Background:

• Occludin (OCLN) is a key component of epithelial tight junctions.
• OCLN serves as a cellular receptor for hepatitis C virus (HCV) entry.
• Monoclonal antibodies (mAbs) targeting OCLN extracellular loops can inhibit HCV infection.

Purpose of the Study:

• To develop smaller, functional antibody-based probes targeting OCLN.
• To assess the efficacy of OCLN-binding Fab fragments and scFv antibodies in inhibiting HCV infection.
• To evaluate the potential of these novel probes as therapeutic agents and research tools.

Main Methods:

• Conversion of anti-OCLN mAbs into monovalent Fab fragments and single-chain variable fragment (scFv) antibodies.
• Assessment of binding specificity and affinity of Fab and scFv fragments to OCLN.
• In vitro assays to evaluate the inhibitory effect of Fab and scFv fragments on HCV infection.

Main Results:

• Fab fragments and scFv antibodies retained binding specificity and affinity comparable to parental mAbs.
• Both Fab fragments and scFv antibodies demonstrated significant inhibition of in vitro HCV infection.
• The developed monovalent OCLN-binding probes are small and functional.

Conclusions:

• Monovalent Fab fragments and scFv antibodies targeting OCLN are effective inhibitors of HCV infection.
• These novel OCLN-binding probes represent promising candidates for antiviral drug development.
• The study provides valuable tools for biological and pharmaceutical research involving OCLN.