Fig. 1.
The 49E10 mutant displays wild type growth in tissue culture but not in vivo.
A. E10 parasites were compared to 49E10 parasites in an acute mouse model by i.p. injection of either 5×105 or 1.5×106 tachyzoites into 4 mice each. Morbidity and mortality were monitored during the course of infection. Shown is a representative experiment of at least three independent experiments at similar doses.
B. Coverslips of confluent HFFs were maintained in 10% serum (left) or changed to no serum media (right) for 16 hours before infection with either E10 or the 49E10 mutant. Parasites were allowed to grow for 24 hours before cells were fixed and stained to visualize parasites. The numbers in the legend indict the number of parasites per vacuole. One hundred vacuoles per coverslip were counted. The experiment was performed in triplicate and the averages are graphed +/− SD.
C. Competitive fitness assay show that the 49E10 mutant grows equally well as the parental E10 strain in standard tissue culture conditions (black diamonds), but not in vivo (gray circles). Each of the shapes represents an independent tissue culture flask or mouse that was serially passaged. R-squared value for the in vivo experiment is 0.7663.