Snake venomics, experimental toxic activities and clinical characteristics of human envenomation by Bothrocophias myersi (Serpentes: Viperidae) from Colombia.

Venoms of the viperid genus Bothrocophias, restricted to Colombia and Ecuador, are poorly known. Only a proteomic analysis of B. campbelli venom has been described. In this work we present a proteomic study of B. myersi venom, its biological activities, and describe the clinical characteristics of a patient bitten by this species. B. myersi venom mainly consists of phospholipases A2 (54.0%) and metalloproteinases (21.5%), among proteins of twelve different families. This venom exhibited proteolytic, phospholipase A2, myotoxic, edema-forming, and lethal activities. Enzymatic activities did not show statistically significant differences in comparison to Bothrops asper venom, but B. myersi venom displayed weaker hemorrhagic and coagulant activities. Polyvalent Viperidae antivenoms produced in Costa Rica and Colombia cross-recognized B. myersi venom by ELISA, however only the latter neutralized its lethal activity in mice when tested at a ratio of 3 mg venom/mL antivenom, suggesting it should be useful to treat envenomings inflicted by this species. A patient bitten by B. myersi developed edema and myotoxicity, evidenced by an increased creatine kinase activity in plasma. A good correlation was found between experimental biological activities of Bothrocophias myersi venom and the clinical features of an envenoming provoked by this species. SIGNIFICANCE: The proteomic characterization, toxicity, immunorecognition and neutralization of Bothrocophias myersi venom have been determined for the first time. The distribution of this pit viper is restricted to Colombia and Ecuador, and its venom contains a high proportion of phospholipases A2 and metalloproteinases. The polyvalent antivenom produced in Colombia neutralized the lethal activity of this venom in vivo, and therefore should be effective in the treatment of envenomings by this snake.