ANTIGENIC CROSS-REACTIVITY AMONG THE VENOMS FROM SEVERAL SPECIES OF BRAZILIAN SCORPIONS

The venoms of seven species of scorpions living in different regions o f Brazil were analysed with regard to their lethality, antigenic cross -reactivity and ability to induce antibody production. In mice, the te sted scorpion venoms can be grouped as: (a) highly toxic: Tityus stigm urus Thorell (LD(50) = 0.773 mg/kg), Tityus bahiensis (Perty) (LD(50) = 1.062 mg/kg), Tityus serrulatus Lutz and Mello (LD(50) = 1.160 mg/kg ), and Tityus costatus (Karsch) (LD(50) = 1.590 mg/kg), (b) moderately toxic: Tityus cambridgei Pocock (LD(50) = 12.136mg/kg); and (c) pract ically nontoxic: Rhopalurus agamemnon (Koch) (LD(50) = 36.363 mg/kg), and Brotheas amazonicus Lourenco (LD(50) = 90.909 mg/kg). On electroph oresis the venoms showed many protein bands displayed along the chroma togram, most of them cross-reacting in immunoelectrophoresis and immun oblotting using horse anti-T. serrulatus, anti-T. bahiensis or anti-T. serrulatus + T. bahiensis sera as probes. The antibodies present in t hese antivenoms combine with venom components as measured in vitro by the ELISA assay, and neutralize their lethal effects in vivo. These re sults indicate that horse antivenoms against a mixture of T. serrulatu s and T. bahiensis venoms or only against T. serrulatus venom yield an antibody population able to neutralize the toxic effects found in all venoms studied.