Fig. 4

Inducible nitric oxide synthase (iNOS) may be involved in adverse pregnancy outcomes during malaria. A Pregnancy outcomes in uninfected pregnant wild-type (WT) mice and immunized pregnant WT and iNOS-knockout (KO) mice infected with P. berghei NK65. Number, survival rate, and weight of fetuses were measured at delivery. Experiments using three mice were performed in triplicate with similar results. Asterisks indicate a significant difference compared with the pregnancy period of uninfected pregnant WT mice (P < 0.05, Tukey–Kramer and Dunnett test). Dagger indicates a significant difference compared with the pregnancy period of immunized pregnant WT mice infected with P. berghei NK65. B–G Representative haematoxylin and eosin-stained placental sections are shown. Placentas were obtained from uninfected pregnant WT mice and immunized pregnant WT and iNOS-KO mice infected with P. berghei NK65 on day 17 post-mating. B–D Low magnification images of placentas. Scale bars indicate 200 μm. E–G Higher magnification of the labyrinth region. Scale bars indicate 100 μm. B, E Uninfected pregnant WT mice. C, F Immunized pregnant WT mice infected with P. berghei NK65. D, G Immunized pregnant iNOS-KO mice infected with P. berghei NK65. Data are representative of six independent experiments