Application of phage display for the development of a novel inhibitor of PLA2 activity in Western cottonmouth venom

Snakebite envenomation is an important global health concern. The current standard treatment approach for snakebite envenomation relies on antibody-based antisera, which are expensive, not universally available, and can lead to adverse physiological effects. Phage display techniques offer a powerful tool for the selection of phage-expressed peptides, which can bind with high specificity and affinity towards venom components. In this research, the amino acid sequences of Phospholipase A2 (PLA2) from multiple cottonmouth species were analyzed, and a consensus peptide synthesized. Three phage display libraries were panned against this consensus peptide, crosslinked to capillary tubes, followed by a modified surface panning procedure. This high throughput selection method identified four phage clones with anti-PLA2 activity against Western cottonmouth venom, and the amino acid sequences of the displayed peptides were identified. This is the first report identifying short peptide sequences capable of inhibiting PLA2 activity of Western cottonmouth venom in vitro, using a phage display technique. Additionally, this report utilizes synthetic panning targets, designed using venom proteomic data, to mimic epitope regions. M13 phages displaying circular 7-mer or linear 12-mer peptides with antivenom activity may offer a novel alternative to traditional antibody-based therapy.