Pathophysiological Effects of the North Africa's Dangerous Scorpions and Antivenom Neutralization Efficacity: Unveiling the Spleen's Response.

The scorpion envenomations represent a serious public health issue, especially in North Africa. Their venom is known as a poison causing fatal complications. However, antivenom is the effective therapeutic approach available, showing a wide distribution in tissue compartments. Despite large-scale studies on the pathogenesis of scorpion envenomations, the spleen remains an organ not fully highlighted, even its major implication on the organism's immune response. In order to have a full view on this point, the focus will be directed for the first time towards the neutralization effects of a rabbit-made antivenom on the spleen level against the North Africa's dangerous scorpions: Androctonus australis hector (Aah), Androctonus mauretanicus (Am), and Buthus occitanus (Bo) by the direct or cross-reactivity reaction. Firstly, the acute toxicity was assessed by determining the Median Lethal Dose (LD₅₀) and Sublethal Dose (sLD), then the electrophoretic profile was generated. The Median Effective Dose 50% (ED₅₀) was conducted against each venom before proceeding to the histological examination in mouse splenic tissue, with and without administration of scorpion antivenom. Our results revealed that the spleen histo-structure was highly damaged by the toxic effect of Am, followed by Aah and Bo. Insightfully, the antivenom administered even 2 h later was able to essentially neutralize congestion and the presence of giant cells, as well as a significant reduction in red pulp hyperplasia and hemorrhagic foci. Based on these findings, the antivenom showed important effects against another vital organ highly targeted by the scorpion venoms, in view of adopting immunotherapy, especially in Morocco.