Toxicity of two North AmericanLoxosceles(brown recluse spiders) venoms and their neutralization by antivenoms

Abstract

The toxic, biochemical, and immunological characteristics of L. boneti and L. reclusa venoms and its neutralization by anti-L. boneti and anti-L. reclusa antivenoms were studied. The electrophoretic profile showed very similar patterns and the toxic activities were very close. Immunological studies showed cross-reactivity among L. boneti and L. reclusa venoms, with L. boneti and L. reclusa experimental antivenoms, and anti-L. gaucho and anti-L. laeta antivenoms. The venom of L. laeta showed low immunological reactivity with the North American Loxosceles antivenoms. Experimental anti-North American Loxosceles antivenoms protected mice of the systemic toxicity and were able to prevent necrosis in rabbit skin after the injection of the venom. Both antivenoms displayed cross neutralization. The results showed that both Loxosceles venoms have very close toxic, biochemical, and immunological characteristics, and that either monospecific antivenoms or an antivenom raised with L. boneti and L. reclusa venoms as immunogens could be useful for treating bites by North American Loxosceles spiders.

General biochemical and immunological characterization of the venom from the scorpion Tityus trivittatus of Argentina

“…Among the most prominent observations were a generalized congestion and lesions in lungs, heart and liver damage with pancreatic lesions in some cases, similar to the results obtained previously when using a mixture of venoms from scorpions of different regions of the country (de Roodt et al, 2001) and with the lesions described for other Tityus venoms (Freire- Maia, 1990;D'Suze et al, 1999;2004;Cupo et al, 2003;de Roodt et al, 2009). The pulmonary lesions observed in this study are consistent with those described in mice injected experimentally with venom of Tityus confluens and other Tityus (de Roodt et al, 2009) and with the venom of other Buthidae non American scorpions like Buthus occitanus tunetanus, Androctonus australis Hector, Leiurus quinquestriatus haebraus, Parabuthus transvaalicus and Parabuthus granulatus (de Roodt et al, 2006). In addition, the congestive pulmonary lesions are similar to those recently described in rats injected with venom of Buthus occitanus tunetanus (Ben Nasr et al, 2009).…”

Low Health System Performance, Indigenous Status and Antivenom Underdosage Correlate with Spider Envenoming Severity in the Remote Brazilian Amazon

“…Interestingly, spider antivenom severity correlates with antivenom underdosage in remote areas with lower health system performances. Although data on Loxosceles antivenom efficacy are conflicting and no placebo-controlled trials in human beings have been undertaken [ 61 , 62 ], studies indicate attenuation in dermonecrotic arachnidism in rabbits [ 63 , 64 ] and in the systemic envenoming in mice [ 64 ] and rabbits [ 65 ]. For Phoneutria antivenoms, antivenom therapy efficacy evidence in humans is still scarcer [ 10 ].…”

Brown Recluse Spider Bite Mediated Hemolysis: Clinical Features, a Possible Role for Complement Inhibitor Therapy, and Reduced RBC Surface Glycophorin A as a Potential Biomarker of Venom Exposure

“…However, eculizumab does not carry an FDA approval for the treatment of BRSB mediated hemolysis and the clinical utility of eculizumab therapy in this population has not been established in vivo . It may also be useful to compare the efficacy of eculizumab against loxosceles anti-venoms, which are not currently FDA approved or available in the United States [28]. …”