Host Cell Vimentin Restrains Toxoplasma gondii Invasion and Phosphorylation of Vimentin is Partially Regulated by Interaction with TgROP18

He, Cheng; Kong, Ling; Zhou, Lijuan; Xia, Jing; Wei, Haixia; Liu, Min; Peng, Hongjuan

In our study, we observed variable levels of vimentin protein expression in different mouse tissues, with much lower levels in brain and spleen compared with the other tissues investigated (lung, kidney, liver, and heart; Figure 5 ). T. gondii exhibits a definite neurotropism and much higher number of cysts located in the brain than other organs [47] . Low vimentin expression levels favor T. gondii invasion into host cells, which is consistent with the fact of more cysts in the brain than in other organs. Strong and persistent cell-mediated immunity, mainly Th1 responses, is activated by T. gondii infection, and can protect the host from rapid tachyzoite proliferation and consequent pathology [48, 49] . CD4 + and CD8 + T cell populations are increased in the spleens of mice immunized with T. gondii [50] ; therefore, although low expression levels of vimentin were also observed in this organ, it develops no more cysts than other tissues.