VENENO DE Tityus Serrulatus: uma ferramenta biotecnológica na modulação do sistema imunológico

Abstract

The scorpions of the genus Tityus are really important to public health in Brazil due to accidents and venom s potentiality to cause serious clinical cases, and sometimes fatal, especially in children. The poison of these arachnids induces an inflammatory response, has antimicrobial activity and furthermore maintains the survival of animals with induced by cecal ligation and puncture (CLP) sepsis. The purpose of this study were: evaluate the kinetics of activation and cell migration by making a comparison between venoms (T.serrulatus and T.bahiensis) in naive animals (Article 01); investigate the recruitment of cells to the lymphoid organs, the activation of these cells and cytokine production after stimulation with the venom of T. serrulatus in naive animals (Article 02); and investigate the effect of T. serrulatus scorpion venom on the immune system of animals which was induced polymicrobial infection cecal ligation and puncture - CLP (Article 03). The animals received the poisons of T. serrulatus or T. bahiensis, intraperitoneally and after 30, 120 and 360 minutes were sacrificed for quantification of cellularity in lymphoid organs (Article 01). In Article 02, the mice received only the venom of T. serrulatus and after 30, 120 and 360 minutes were sacrificed for quantification of cellularity in lymphoid, investigation of cell activation and cytokine production organs. In Article 03, the mice received venom of T. serrulatus 6h before induction of lethal sepsis by CLP. After 12 hours of induction of CLP, a part of animals was separated for monitoring survival and another part were sacrificed, blood was collected for platelet count and obtain serum for determination of serum nitrite and quantification of cytokines. Quantification of cellularity of lymphoid organs and bronchoalveolar lavage was performed by microscopy. The lung was removed to perform the histological sections to analyze the edema and the influx of cells into the lung cavity. The activation was also assessed by the release of hydrogen peroxide by peritoneal cells. The treatment was always done in non-lethal dose of 200 μg/kg, intraperitoneal or subcutaneous injection. The results showed that the poisons interfere with recruitment of cells to the lymphoid organs. The venom of T. serrulatus led to an increased number of blood neutrophils and increased IL -6, TNF- α, IL-10 reduced the number of cells in the spleen and peritoneum associated with an increase in the number of cells in the lymph node. In the experiment in which CLP was induced in the animals, poison prevented death of mice with polymicrobial infection, reduced pulmonary edema, did not reduce inflammatory cytokines. There was an increase in IL-6 and MCP-1 in BAL. Increased IL-10 has been identified in the serum of treated animals in which the poison was induced by CLP. The poison is an important biotechnological tool in maintaining the survival of infectious conditions capable of inducing death, because it stimulates the immune system, inducing cell activation with release of cytokines and microbicidal products such as, for example, hydrogen peroxide. The scorpion venom is considered an important source of substances that constitute raw materials or templates for the synthesis of new drugs or prophylactic bioproducts low cost for the control of infections, acting as antimicrobial and at the same time maintaining the immune response avoiding lethality