Figure 6. Mortality rates of nude, MHC II^-/- and MHC I^-/- STAg-pretreated and infected mice.

The mortality rate for 8 mice from each group, nude (A), MHC II^-/- (B) and MHC I^-/- (C) was determined. Nude mice STAg- or PBS-pretreated survived significantly longer than euthymic control T. gondii-infected mice (χ²=10.03; p = 0.0015; df = 2). MHC II^-/- -STAg-pretreated mice were more resistant to infection than PBS-pretreated-MHC II^-/- or -C57BL/6 mice (χ²=4.493; p = 0.034; and χ²=4.120; p = 0.424; df = 2, respectively). MHC I^-/- pretreated with PBS or STAg were more resistant to infection than PBS-pretreated-C57BL/6 mice (χ²=9.069; p = 0.0026; χ²=3.974; p = 0.0462; df = 2, respectively).