The imbalance of TNF and IL-6 levels and FOXP3 expression at the maternal-fetal interface is involved in adverse pregnancy outcomes in a susceptible murine model of congenital toxoplasmosis.

Vertical transmission of Toxoplasma gondii leads to adverse pregnancy outcomes depending on the time at which the infection occurs and the immunological state of the mother. C57BL/6 and BALB/c mice have been described as susceptible and resistant mouse lineages to congenital T. gondii infection, respectively. This study aimed to elucidate the systemic and local cytokine profile of pregnant mice infected with T. gondii and whether the expression of the transcription factor FOXP3, related to T regulatory cells, is associated with the resistance/susceptibility of these lineages of mice in the context of experimental congenital toxoplasmosis. For this purpose, C57BL/6 and BALB/c females were orally infected with the T. gondii ME-49 strain on the day of vaginal plug detection or day 14 of gestation, examined 7 or 5 days later, respectively, as models of early and late pregnancy. Cytokine levels were measured systemically and in the uterus/placenta. Additionally, the uterus/placenta were evaluated macroscopically for resorption rates and histologically for parasite and FOXP3 immunostaining. The FOXP3 protein expression was also evaluated by western blotting assay. It was found that, during early pregnancy, the infection leads to high IFN-γ, TNF and IL-6 levels systemically, with the TNF levels being higher in C57BL/6 mice. At the maternal-fetal interface, the infection induced high levels of IFN-γ in both mouse lineages; however, higher levels were observed in BALB/c, while high TNF and IL-6 levels were found in C57BL/6, but not in BALB/c mice. In contrast, in late gestation, T. gondii interfered less strongly with the cytokine profile. In early pregnancy, a reduction of FOXP3 expression at the maternal-fetal interface of infected mice was also observed, and the reduction was larger in C57BL/6 compared with BALB/c mice. Additionally, the parasite was seldom found in the uterus/placenta. Thus, the worse pregnancy outcomes observed in C57BL/6 mice were associated with higher TNF systemically, and TNF and IL-6 at the maternal-fetal interface, with lower FOXP3 expression.

The ethanolic extract of the fungus Trichoderma stromaticum decreases the Toxoplasma gondii replication in vitro and ameliorates the experimental toxoplasmosis in vivo.

Trichoderma are fungi that are well-known to inhibit the growth of a variety of plant pathogens. Currently, there is an increasing search for new drugs to treat toxoplasmosis. The aims of this study were to investigate the effect of ExtTs in the control of Toxoplasma gondii proliferation in vitro and the course of toxoplasmosis in a mouse model. Firstly, the cytotoxicity of the ExtTs was evaluated by cultivating macrophages with different concentrations of the extract and cell viability was assessed by the MTT assay. Next, the infectivity of the T. gondii treated with extract was analyzed by infecting J774 macrophages. To evaluate the effect of the ExtTs in vivo, C57BL/6 mice were infected orally with T. gondii, ME-49, treated daily with ExtTs, and clinical, biochemical and histological changes were monitored. It was demonstrated that the extract did not affect the host cellular viability and, the treatment of parasites with ExtTs altered their morphology and decreased their ability to proliferate inside macrophages. Additionally, the treatment of mice with ExtTs decreased the parasitism and inflammation in the small intestine and liver of infected mice in parallel with increased IL-10/TNF ratio systemically and prevented alterations to serum VLDL and triglyceride levels. Thus, ExtTs could be considered an alternative/complementary therapy to control toxoplasmosis.