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Updated: Aug 25, 2026

Microdissection of Black Widow Spider Silk-producing Glands
Published on: January 11, 2011
Sex-linked variation of Loxosceles intermedia spider venoms
K Cristina de Oliveira1, R M Gonçalves de Andrade, A L Giusti
1Laboratory of Immunochemistry, Butantan Institute, Saõ Paulo, SP, Brazil.
Abstract:
In order to investigate intraspecific differences in Loxosceles intermedia spider venom we compared some biological properties of male and female venoms. Females produced higher amounts of venom than males. Furthermore, female venom presented more potent dermonecrotic and complement-dependent activities than male venom. Interestingly, the F35 toxin, a dermonecrotic and complement-dependent haemolytic factor, was also present in greater amounts in female venom, as demonstrated by ELISA. Therefore, the higher production and increased toxicity of venom in female specimens as compared to males may contribute to the variability observed in the severity of envenoming caused by L. intermedia spiders.
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