Therapeutic epitopes of Leptospira LipL32 protein and their characteristics.

Two LipL32-specific mouse monoclonal antibodies (mAbLPF1 and mAbLPF2) which neutralized Leptospira-mediated hemolysis in vitro and rescued hamsters from lethal Leptospira infection were produced. In this communication, locations and characteristics of the protective epitopes of the mAbs were studied by using a truncated LipL32 recombinant protein based-immunoassay and phage consensus mimotope identification and multiple alignments. The mAbLPF1 epitope consisted of P243, L244, I245, H246, L252 and Q253 on the LipL32 protein; it is mapped on the surface-exposed region of non-continuous β13-turn and C-terminal amphipathic α6 helix with hydrophobic patch, contributing to phospholipid/host cell adhesion and membrane insertion on one side, and hydrophilic, acidic and basic amino acid residues on another side.