Specific heterologous F(ab')2 antibodies revert blood incoagulability resulting from envenoming by Lonomia obliqua caterpillars.

Contact with Lonomia obliqua caterpillars results in a bleeding syndrome characterized by hemorrhage and blood coagulation disturbances. Conventional therapy using antifibrinolytics or cryoprecipitates has been unable to treat pathophysiologic alterations. As antivenoms are effective therapy for treatment of victims of venomous animals, a process of manufacturing a specific antilonomic serum by immunizing horses with Lonomia caterpillar bristle extracts (LBE) was developed. Lonomia caterpillar bristle extracts exhibited several protein bands on SDS-PAGE, induced blood coagulation abnormalities and lethality in mice, and stimulated specific antibody production in horses. Sera obtained from immunized horses were rich in anti-LBE specific antibodies distributed among the horse IgG isotypes. These antibodies had the ability to recognize various LBE antigens as well as to neutralize their coagulopathy-inducing activity. The antivenom manufactured by the developed process was composed of purified and sterilized F(ab')2 with ED50 = 38.61 microl, potency = 0.29 mg/ml, and 95% confidence limit of potency 0.20-1.36.

Cross reactivity of different specific Micrurus antivenom sera with homologous and heterologous snake venoms.

Coral snakes are the only Elapids in America. They are represented by three genera: Leptomicrurus, Micruroides and Micrurus, of which the latter are the most abundant and diversified group. Little is known about the biochemistry of Micrurus venoms due to low availability. Here, we present a study on the cross reactivity of different specific Micrurus antivenom with homologous and heterologous snake venoms in order to contribute to the generation of more efficient antiserum for therapeutic purposes. The three specific antisera tested, anti-Micrurus corallinus, anti-Micrurus frontalis, and anti-Micrurus spixii, as well as the bivalent anti-elapid venom sera, raised against a mixture (50% each) of Micrurus frontalis and Micrurus corallinus venoms, were assayed by Western Blot against Micrurus and non-Micrurus elapid venoms. An antisera raised against a recombinant alpha-neurotoxin-like protein from Micrurus corallinus venom, only reacted in Western blot with its homologous venom, indicating that this protein is specific for Micrurus corallinus coral snake.

Cross reactivity of different specific Micrurus antivenom sera with homologous and heterologous snake venoms

Coral snakes are the only Elapids in America. They are represented by three genera: Leptomicrurus, Micruroides and Micrurus, of which the latter are the most abundant and diversified group. Little is known about the biochemistry of Micrurus venoms due to low availability. Here, we present a study on the cross reactivity of different specific Micrurus antivenom with homologous and heterologous snake venoms in order to contribute to the generation of more efficient antiserum for therapeutic purposes. The three specific antisera tested, anti-Micrurus corallinus, anti-Micrurus frontalis, and anti-Micrurus spixii, as well as the bivalent anti-elapid venom sera, raised against a mixture (50% each) of Micrurus frontalis and Micrurus corallinus venoms, were assayed by Western Blot against Micrurus and non-Micrurus elapid venoms. An antisera raised against a recombinant á-neurotoxin-like protein from Micrurus corallinus venom, only reacted in Western blot with its homologous venom, indicating that this protein is specific for Micrurus corallinus coral snake.

Development of an antivenom against toxins of Lonomia obliqua caterpillars.

Skin contact with caterpillars of Lonomia moths causes haemostatic disorders that may evolve into a haemorrhagic syndrome. Replacement therapy has been shown to exacerbate the clinical symptoms of this envenoming. In this study it is shown that horses immunized with a bristle extract of L. obliqua caterpillars produced IgG antibodies that completely neutralized, in vitro, the toxin(s) responsible for the blood incoagulability observed in rats. This antivenom offers the possibility of specific treatment for envenoming caused by contact with caterpillars of Lonomia moths.

Antigenic cross-reactivity among components of Brazilian Elapidae snake venoms.

Snake venoms from M. corallinus (LD50 = 7.1 +/- 0.83 micrograms), M. frontalis (LD50 = 19.3 +/- 3.13 micrograms), M. ibiboboca (LD50 = 19.8 +/- 2.07 micrograms) and M. spiixi (LD50 = 6.7 +/- 1.25 micrograms) (family Elapidae, genus Micrurus) injected into horses alone or in combination (M. corallinus with M. frontalis) elicit antibody production, as indicated in vivo by neutralization of venom lethality and in vitro by enzyme-linked immunosorbent assay (ELISA), immunoelectrophoresis (IE) and Western blotting (WB). Venom lethality was efficiently neutralized by the antisera, with the monovalent antivenoms being more efficient than the bivalent antivenom. Antibodies against venom components were detected by all antisera at different titers by ELISA. Upon IE, antisera against M. spiixi and M. frontalis venoms cross-reacted with the four types of venoms studied and recognized several molecular components, the precipitin lines obtained had distinct intensities and electrophoretic motilities, whereas the antivenom against M. corallinus only recognized components of its venom but not of the others. All antivenoms cross-reacted with all the elapid venoms in WB revealing several bands with distinct MWs in M. corallinus and M. spiixi venoms, two very sharp and separate bands in M. corallinus venom and a very sharp band of high MW together with several other smaller and faint bands in M. frontalis venom. The data indicate that snake venoms of the genus Micrurus are good immunogens that contain many cross-reactive molecules, and that their toxic components are neutralized more effectively by monovalent rather than by bivalent antivenom.

Antigenic cross-reactivity among components of Brazilian Elapidae snake venoms

Snake venoms from M. corallinus (LD5=7.1 + or - 0.83 µg), M.frontalis (LD50=19.3 + or - 3.13 µg), M. ibiboboca (LD50=19.8 + or - 2.07 µg) and M. spiixi (LD50=6.7 + or - 1.25 µg) (family Elapidae, genus Micrurus) injected into horses alone or in combination (M. corallinus with M. frontalis) elicit antibody production, as indicated in vivo by neutralization of venom lethality and in vitro by enzyme-linked immunosorbent assay (ELISA), immunoelectrophoresis (IE) and Western blotting (WB). Venom lethality was efficiently neutralized by the antisera, with the monovalent antivenoms being more efficient than the bivalent antivenom. Antibodies against venom components were detected by all artisera at different titers by ELISA. Upon IE, antisera against M. spiixi and M. frontalis venoms cross-reacted with the four types of venoms studied and recognized several molecular components, the precipitin lines obtained had distinct intensities and electrophoretic motilities, whereas the antivenom against M. corallinus only recognized components of its venom but not of the others. All antivenoms cross-reacted with all the elapid venoms in WB revealing several blands with distinct MWs in M. corallinus and M. spiixi venoms, two very sharp and separate bands in M. corallinus venom and a very sharp band of high MW together with several other smaller and faint bands in M. frontalis venom. The data indicate that snake venoms of the genus Micrurus are good immunogens that contain many cross-reactive molecules, and that their toxic components are neutralized more effectively by monovalent rather than by bivalent antivenom