Studies On Function Of Placenta Cell-mediated Immune In Toxoplasma Gondii-infected Pregnancy Mice

Objective To explore the cell-mediated immune function of pregnancy mice's placenta on prevention of Toxoplasma gondii being transmitted to fetus. Methods 1. In present study, we explored the changes on T-cell subsets CD4+ and CD8+ in periphal blood and decidual tissues of Toxoplasma gondii-infected mice by flow cytometry. 2. The immune protecting effect of IFN-r on placenta of Toxoplasma gondii-infected pregnancy mice were observed by transmission electron microscopy. Results 1. The changes on T-cell subsets CD4+ and CD8+ in peripheral blood and decidual tissues of Toxoplasma gondii-infected mice detected by flow cytometry showed as flowers: In peripheral blood, the change of T-cell subsets showed that CD4+ T-cells significantly increased (P <0.01) and CD8+T-cells change little. The ration of CD4+/ CD8+ cells significantly increased (P <0.01). Whereas in decidual tissues, the change of T-cell subsets showed that CD8+ T-cells increased (P <0.05) and CD4+T-cells decreased (P <0.05). The ration of CD4+/ CD8+ cells significantly decreased (P<0.01). 2. Through transmission electron microscopy, we could find that there were a few Toxoplasma gondii but more active macrophages in IFN-y used group comparing with control. Still, the Toxoplasma-killing activity of active macrophages were significantly increased. The majority organs of Toxoplasma gondii within cells were disintegrated.Conclusions 1 , The results suggest that cell-mediated immune of pregnancy mice's placenta has important function on prevention of Toxoplasma gondii being transmitted to fetus. As a special immune apparatus, placental T-cell subsets has a different immunological response comparing with that of peripheral blood in earlier period of acute Toxoplasma godii infected-mice. The increasing of CD8+ T-cell subsets in decidual tissues indicated that there has a reinforcement of Toxoplasma-killing activity of local placenta, which may play an important role in prevention of Toxoplasma gondii being transmitted to fetus. Whereas the decreasing of CD4+ T-cell subsets in decidual tissues may keep the immune microenvironment balance of placenta and thus decrease the abortion rate of pregnancy mice. 2, Reinforcement of placenta cell-mediated immune has some functions on prevention of Toxoplasma gondii being transmitted to fetus. As a main immunoloregulation factor in Toxoplasma gondii infection, IFN-r can apparently increases Toxoplasma-killing activity of immunologically competent cell and thus manifests its immune therapeutic function of prevention of toxoplasma gondii being transmitted to fetus.