Figure 1.

A single CPS or RAS immunization protects mice against experimental cerebral malaria. (A) ECM-free survival following a challenge with 10³ Pb ANKA SPZ i.v. in previously CQ-CPS immunized (n = 8) versus CQ-treated (n = 8) or untreated (non-immunized; n = 4) control animals. (Non-immunized vs. CQ-CPS: P < 0.01; CQ treated vs. CQ-CPS: P < 0.001; Non-immunized vs. CQ treated: P = 0.7, logrank-test). (B) ECM-free survival in i.v. RAS immunized (n = 8) versus untreated (non-immunized; n = 8) control animals following a challenge with 10³ Pb ANKA SPZ i.v. (P < 0.001, logrank-test). (C) ECM-free survival in s.c. DP-CPS immunized (n = 8) versus DP treated (n = 8) or untreated (non-immunized; n = 8) animals (Non-immunized vs. DP-CPS: P < 0.01; DP treated vs. DP-CPS: P < 0.001; Non-immunized vs. DP treated: P = 0.26, logrank-test). (D) Evans Blue staining of the brains of animals with (right) and without (left) clinical signs of ECM (shown are representative pictures). Following i.v. injection of Evans Blue, significantly higher amounts of Evans Blue were detected in the brains of ECM (n = 10) versus non-ECM (n = 13) animals, (P < 0.001, Wilcoxon rank-sum test). (E) Representative MR brain images (MRI assessment) show a high number of microhemorrhages in non-immunized mice with a predominance in the olfactory bulb, while in CQ-CPS and RAS immunized mice only a low number of microhemorrhages is visible (red arrows point to exemplary microhemorrhages).