Heterologous expression of four recombinant toxins from Panamanian scorpions of the genus Tityus and Centruroides for production of antivenom.

ABSTRACT

BACKGROUND: The development of more effective antivenoms remains a necessity for countries where scorpionism is a public health problem. Also, the regionalization of antivenoms may be important for some countries with special scorpionism characteristics. OBJECTIVE: Production of antibodies capable of neutralizing the lethal effect of the venom of three scorpion species from Panama. METHODS: The primary structures of two neurotoxins from T. pachyurus, one from T. cerroazul and another from C. bicolor were elucidated using N-terminal amino acid degradation and Sanger gene cloned sequencing. The obtained mRNA transcripts were cloned and expressed using E. coli vectors. Different bacterial expression conditions were tested and the best culture conditions for each expressed protein is reported. The expressed scorpion toxins were purified by chromatographic methods and used as immunogens in rabbits. RESULTS: The antibodies produced under the reported immunization scheme show better neutralization (ED50) than other reported commercial antivenoms used to neutralize similar species scorpion venoms under similar LD50 conditions. CONCLUSION: The information reported here shows the proof of concept for selecting recombinant immunogens with the ability to produce antibodies for neutralizing the lethal effects of the most important medical species of scorpions in Panama.