In vivo bioluminescence assays.

We infected 4- to 8-week-old female mice (BALB/c, C57BL/6, and various knockout lines, as indicated; Jackson Laboratories) via i.p. injection of 10⁶ Luc-expressing parasites in 200 μl sterile PBS. Acute infections were monitored using bioluminescence imaging by injecting mice with 3 mg d-luciferin in 200 μl sterile PBS. Images were taken using the Ivis Lumina II imaging system (Xenogen Corporation) for 4 min using maximum binning. Images were analyzed using Living Image software to calculate total flux (photons per second) across the entire body of the mouse.