Two consensus scorpion toxins derived from the venoms of the genera Centruroides (NATx, North America), and Tityus (SATx, South America) was rationally designed and recombinantly expressed in Escherichia coli Origami. Both recombinant proteins were produced as inclusion bodies and then purified and refolded in vitro to obtain biologically active isoforms. The expression yield was approximately 1 mg/L for rNATx and 0.5 mg/L for rSATx. Structural characterization by circular dichroism spectroscopy revealed that rNATx and rSATx displayed folding patterns typical of scorpion β-toxins. The purified recombinant toxins were used as immunogens to raise polyclonal antibodies in New Zealand rabbits. The resulting antisera were evaluated for their ability to neutralize isolated toxins and whole scorpion venom. rNATx elicited a stronger immune response and showed superior immunogenicity compared to rSATx. In particular, 1-1.5 mg of anti-rNATx antibodies were sufficient to neutralize up to 3LD50 of venom from the most medically relevant Centruroides species in México. On the other hand, approximately 20 mg of anti-rSATx antibodies were required to neutralize only 2LD50 of Tityus poisons. In addition, T-cell subsets quantified by flow cytometry showed that rNATx is more immunogenic and likely provides improved antivenom efficacy, highlighting its potential application in the development of broad-spectrum antivenoms against scorpion envenomation.
Cardoso-Arenas S, Mejia-Sanchez MA, Miranda-Blancas R, Clement H, Corrales-García L, Arenas I, et al. (2026) Immunogenicity of two representative American consensus scorpion neurotoxins from the genera Tityus and Centruroides. PLoS Nail Trop Dis 20(2): e0013982. https://doi.org/10.1371/journal.pntd.0013982
