Synthetic peptide antigens derived from long-chain alpha-neurotoxins: Immunogenicity effect against elapid venoms

- Peptides derived from the conserved motifs of long-chain a-neurotoxins are able to elicit positive humoral response in rabbits.
- Synthetic peptides generate neutralizing antibodies.
- Venoms of Naja haje, Dendroaspispolylepis and Ophiophagus hannah are partially neutralized by the antisera in a dose-depended manner.
- Depletion of the curare-mimetic activity of the long-chain a-neurotoxins shows the relevance of its toxicity on the overall lethality of the venoms.

Three-finger toxins (3FTXs), especially α-neurotoxins, are the most poorly neutralized elapid snake toxins by current antivenoms. In this work, the conserved structural similarity and motif arrangements of long-chain α-neurotoxins led us to design peptides with consensus sequences. Eight long-chain α-neurotoxins (also known as Type II) were used to generate a consensus sequence from which two peptides were chemically synthesized, LCP1 and LCP2. Rabbit sera raised against them were able to generate partially-neutralizing antibodies, which delayed mice mortality in neutralization assays against Naja haje, Dendrospis polylepis and Ophiophagus hannah venoms.