Heterologous Expression and Immunogenic Potential of the Most Abundant Phospholipase A 2 from Coral Snake Micrurus dumerilii to Develop Antivenoms.

Micrurus dumerilii is a coral snake of clinic interest in Colombia. Its venom is mainly composed of phospholipases A 2 being MdumPLA 2 the most abundant protein. Nevertheless, Micrurus species produce a low quantity of venom, which makes it difficult to produce anticoral antivenoms. Therefore, in this work, we present the recombinant expression of MdumPLA 2 to evaluate its biological activities and its immunogenic potential to produce antivenoms. For this, a genetic construct rMdumPLA 2 was cloned into the pET28a vector and expressed heterologously in bacteria. His-rMdumPLA 2 was extracted from inclusion bodies, refolded in vitro, and isolated using affinity and RP-HPLC chromatography. His-rMdumPLA 2 was shown to have phospholipase A 2 activity, a weak anticoagulant effect, and induced myonecrosis and edema. The anti-His-rMdumPLA 2 antibodies produced in rabbits recognized native PLA 2 , the complete venom of M. dumerilii , and a phospholipase from another species of the Micrurus genus. Antibodies neutralized 100% of the in vitro phospholipase activity of the recombinant toxin and a moderate percentage of the myotoxic activity of M. dumerilii venom in mice. These results indicate that His-rMdumPLA 2 could be used as an immunogen to improve anticoral antivenoms development. This work is the first report of an M. dumerilii functional recombinant PLA 2 .