Análise histopatológica e expressão dos receptores tipo Toll 2 e 4 na placenta de camundongos experimentalmente infectadas com Toxoplasma gondii em diferentes terços gestacionais

Abstract

Failures in conception such as abortion, fetal death and congenital defects may be associated with infectious agents and, in this context, Toxoplasma gondii plays a major role. Given the importance of the placenta in pregnancy and T. gondii infection during gestation, we standardized a murine model pregnant orally infected with 20 tissue cysts of the T. gondii strain ME-49, to analyze histopathologically and to evaluate the expression of TLR 2 and 4 in the placenta, in three different moments of gestation. 19 mating cycles were performed, totalizing 26 pregnant females divided into 4 experimental groups; (G1) control group with pregnant and uninfected females; (G2) pregnant females inoculated in the first gestational third; (G3) pregnant females inoculated in the third gestational third, and (G4) pregnant females inoculated in the third third of gestation. In histopathological analyzes of the placenta and the brains of the females it was possible to observe inflammatory infiltrate and areas of necrosis, especially in infected animals in the second third of gestation. It was possible to detect T. gondii DNA by conventional PCR in the brain of only one infected female in the first gestational third, as well as the expression of TLR 2 and 4 in the placenta was more evidenced in infected animals at the beginning of gestation. In this way, we demonstrated that the murine model is efficient for studies related to congenital toxoplasmosis and that the changes observed histopathologically are dependent on the time of infection.