Epitope-directed monoclonal antibody production against Staphylococcus aureus enterotoxin B enabled by in silico...

Developing highly specific antibodies against Staphylococcus aureus enterotoxin B (SEB) - a potent toxin previously employed as a biological weapon - is critical for accurate detection and effective therapeutic interventions. However, generating such highly specific antibodies remains a significant challenge. This study designed novel SEB immunogens, 4PF and 4P-F-4P, using an in silico methods for linear B-cell epitope prediction. Compared with the traditional full-length SEB immunogen, epitope-directed engineered immunogens induced antisera in mice with enhanced specificity and affinity against SEB. Monoclonal antibodies (mAbs) derived from these novel immunogens exhibited minimal cross-reactivity (CRs) with other staphylococcal enterotoxins ranging from 0.1 % to 3.6 %. In contrast, the mAbs derived from the full-length SEB immunogen showed broader CRs ranging from 0.1 % to 1037 %. Molecular simulations revealed that the enhanced specificity of the mAbs was mediated by hydrogen bonding interactions with the high-specific amino acid residues on SEB. This study provided a practical strategy for the generation of antibodies with high specificity and affinity, offering valuable insights for future immunogen design.