FIG. 2.
Effect of in vivo neutralization of IL-12 or IFN-γ on
resistance to acute infection with different strains of T.
cruzi. Swiss mice were infected with 5,000 trypomastigotes of
T. cruzi CL, Y, or Colombiana. Animals were treated with
either an unrelated MAb (■, black bars), an anti-IFN-γ MAb (○,
white bars), or an anti-IL-12 MAb
(
, gray
bars) 1 day prior to infection and once a week afterward. The levels of
parasitemia (left panels) and the rates of mortality (right panels)
were monitored daily until the end of the experiment. For each datum
point presented in the parasitemia curve the average and positive
standard deviation are shown for three to six animals per group.
Similar numbers of animals were used for the mortality study. This
experiment was repeated once and yielded identical results. Note that
the scale indicating the level of parasitemia (left panels) is
different for each T. cruzi strain.