Study of the neutralization potential of the anti-recombinant Sphingomyelinases D serum, on the toxic effects of Loxosceles spider venoms.

Author(s)

Daniel Manzoni de Almeida

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2007-11-29

Examining board members

Denise Vilarinho Tambourgi; Sandra Helena Poliselli Farsky; Maria de Fátima Domingues Furtado

• Advisor: Denise Vilarinho Tambourgi

Abstract

Envenomation by spiders of species L. laeta, L. intermedia and L. gaucho causes local dermonecrosis and systemic effects. The main toxic component is endowed with sphingomyelinase D (SMase D) activity. The aim of this study was to compare the neutralization potentials of the anti-SMases D and the anti-arachnidic sera, against the toxic effects of venoms of these three species. The analysis by western blot has revealed that the anti-arachnidic serum was able to recognize the majority of the components present on the venoms of the three species, but anti-SMases D has recognized only components of 30-35 kDa, which corresponds to natives SMases D. By ELISA, it has been determined that the anti-SMases D serum contains higher titres of IgGT, IgGa, b and c than the anti-arachnidic serum. Serum neutralization tests have showed that the anti-SMases D serum has better inhibitory shingomyelinasic, dermonecrotic and haemolytic activities of the venoms from L. intermedia and L. laeta. For L. gaucho venom, the results have been similar or better than the anti-arachnidic serum. Although the anti-SMases D serum shows a significant neutralization potential, it is necessary the inclusion of a SMase D from L. gaucho venom, to obtain a efficient antiserum against this venom. (AU)