IL-4 has functions similar to those of IL-10, which promotes the proliferation and differentiation of activated B cells. IL-10 can act as a co-stimulator of the proliferation of mast cells and peripheral lymphocytes and plays a role in the development of mastocytosis after parasitic infections by potentiating CCI-779 clinical trial the effects of IL-3 and IL-4 [26]. IL-4 and IL-10 are considered to favour T. gondii proliferation in macrophages [27]. It has been demonstrated that IL-10-knockout mice fail to survive in the early phase of a T. gondii infection [28], and significantly increased

mortality occurs during acute T. gondii infection in IL-4-knockout mice compared with wild-type mice [29]. These results imply an essential role of

IL-4 and IL-10 in T. gondii infection. However, pVAX1–TgCyP did not lead to a Th2-type immune response in this study, as the production of IL-4 and IL-10 were maintained at the same levels among all the groups. IFN-γ has been associated with a proliferation of T. gondii in macrophages [27]. IFN-γ production in response to intracellular microbial exposure is critical to the development of host protective immunity [30]. Our results showed that high IFN-γ production was induced by TgCyP in the experimental mice, which confirmed the hypothesis that CyP-induced IL-12 is important for the IFN-γ production [18, 27]. Therefore, MI-503 research buy we can conclude that TgCyP can act as an IFN-γ inducing factor

and contribute to the control of toxoplasmosis. Overall, Progesterone we can infer that a prominent Th1-type immune response was developed in response to the TgCyP DNA vaccine. Furthermore, TgCyP also induced the nitro oxide production, which can inhibit parasite replication and trigger a conversion from the highly dividing tachyzoite to the slowly replicating bradyzoite form [31]. However, further study is required to confirm this hypothesis. To investigate the protective efficacy of DNA vaccines against T. gondii challenge, a suitable animal model and suitable T. gondii strains must be selected. Several murine models have been widely used for the study of toxoplasmosis, such as BALB/c, C57BL/6 and C3H mice. BALB/c mice were selected as target animals in this study. Until now, there has been no effective vaccine that produced complete protection against intra peritoneal challenge with the T. gondii RH strain [32-34]. In this study, pVAX1-TgCyP extended the survival time in BALB/c female mice challenged with 500 tachyzoites of T. gondii virulent RH strain when compared with controls. The survival time of pVAX1-TgCyP-immunized mice was similar to survival times of mice immunized by several other single-gene DNA vaccines (such as TgMIC3 and TgADF) in BALB/c mice [11, 12, 33]. In addition, the survival rate of the pVAX1-TgCyP group reached to 37·5%, which indicates significant protection induced by TgCyP.