Humanized synthetic nanobody library for antivenom development.

Area of Science:

• Biotechnology
• Immunology
• Protein Engineering

Background:

• Humanized synthetic nanobodies offer advantages like high specificity, small size, and reduced immunogenicity for therapeutic development.
• Developing novel nanobody libraries is crucial for advancing biomedical research and creating targeted therapies.

Purpose of the Study:

• To construct and validate a novel humanized synthetic nanobody library.
• To identify high-affinity nanobodies capable of inhibiting snake venom Asp49 phospholipase A2 (PLA2) activity.

Main Methods:

• A humanized synthetic nanobody library was constructed by combining eight sub-libraries with human framework regions and camelid-derived complementarity-determining regions (CDRs).
• Phage display bio-panning was performed against a synthetic peptide mimic of Asp49 PLA2, followed by ELISA screening of selected clones.
• The inhibitory potential of the highest-affinity nanobodies against Asp49 PLA2 enzymatic activity was assessed.

Main Results:

• The constructed nanobody library achieved a titer of 1.8 × 10^8 CFU/mL with high insert integrity.
• Screening identified 16 high-affinity nanobody clones, with four demonstrating significant binding to the target antigen.
• All four selected nanobodies effectively inhibited the enzymatic activity of Asp49 PLA2.

Conclusions:

• The developed humanized synthetic nanobody library is functional and effective for identifying high-affinity binders.
• The identified nanobodies show promise for applications in biomedical research and the development of novel antivenoms against snake venom.
• This platform technology has broad potential for therapeutic antibody development against various targets.