Using structural analysis to generate parasite-selective monoclonal antibodies.

Area of Science:

• Parasitology
• Structural Biology
• Immunology

Background:

• Antibody-based diagnostics for parasitic infections face challenges differentiating host and pathogen proteins.
• Filariasis diagnosis is complicated by the nocturnal periodicity of Brugia malayi parasites, hindering microscopic detection.

Purpose of the Study:

• To develop highly specific monoclonal antibodies for diagnosing Brugia malayi filariasis using a structure-guided approach.
• To identify and synthesize peptide regions of B. malayi asparaginyl-tRNA synthetase (AsnRS) suitable for antibody generation.

Main Methods:

• Comparative sequence alignment of B. malayi and human AsnRS to identify unconserved regions.
• Crystallographic structure analysis to pinpoint surface-accessible, B. malayi-specific peptide epitopes.
• Computational analysis (Sequery, SSA) and NMR to predict and confirm peptide conformational stability.
• Synthesis of a 22-residue peptide and subsequent immunization of mice to generate monoclonal antibodies (mAbs).

Main Results:

• Four IgG(1) mAbs were generated that specifically recognized the synthetic peptide and native B. malayi AsnRS.
• These mAbs demonstrated high specificity, binding to parasite AsnRS but not human AsnRS, confirmed by various assays.
• The study successfully validated the use of structural modeling for selecting effective peptide targets for antibody production.

Conclusions:

• Structure-guided selection of peptides is a successful strategy for developing highly specific monoclonal antibodies against parasitic targets.
• The developed mAbs offer a promising tool for improved serodiagnosis of Brugia malayi filariasis.
• This approach enhances the reliability of antibody-based diagnostics for parasitic diseases.