Phage display technology for fabricating a recombinant monoclonal ScFv antibody against tetanus toxin

Tetanus is a specific infectious disease, often associated with lower immunization in developing countries and catastrophic events (such as earthquakes). Millions of people, especially children, die every year from tetanus disease. Therefore, it is necessary to devise a rapid and sensitive detection method for tetanus toxin to ensure an early diagnosis and clinical treatment of tetanus. The current study looks at developing a novel, high specific, low-cost, and sensitive ScFv antibody. It is capable of tetanus detection immunoassays in clinical diagnosis, suspicious foods, and water monitoring. For this regard, a high-quality phage display antibody library (8.7 × 10⁷ PFU/ml) was constructed. Tetanus-specific antibodies with high affinity retrieved from libraries. After phage rescue and four rounds of biopanning, clone screening was performed by phage ELISA. Recombinant antibodies expressed from the AC8 clone showed the highest affinity for tetanus. SDS-PAGE and western blotting confirmed the presence of a high-quality, pure ScFv band at 32 kDa. ELISA was used to determine the affinity value, estimated to be around 10^-8 M. The results suggest that the proposed detection method by ScFv antibodies is an alternative diagnostic tool enabling rapid and specific detection of the tetanus toxin.