Figure 1.
Administration of α-GalCer to mice inhibits the development of P. yoelii liver stages. (A) BALB/c and C57BL/6 mice were injected i.p. with different doses (10 ng, 100 ng, or 1 μg) of α-GalCer in 0.025% polysorbate-20, control vehicle (0.025% polysorbate-20 in PBS), or PBS. Two days later the mice were challenged i.v. with 1 × 105 P. yoelii sporozoites, and after 42 h their livers were removed and their rRNA was measured by semiquantitative competitive RT-PCR (30). (B) A single dose of 1 μg of α-GalCer was administered to five mice between 5 days before (−5) and 1 day after (+1) sporozoite challenge. The parasite burden in the liver was measured, as in A. The results represent one of two similar experiments expressed as the mean ± SD of five mice.