Extended Data Figure 5. Parasite intestinal load measured by qPCR correlates with faecal shedding and tissue luminescence.
a, Mice (n = 4) were infected with 50,000 UGA2 FLuc oocysts and imaged after 1 week. Mice were killed and the small intestine was resected and imaged (representative image shown). Infection of the intestine ranged in intensity from heavy in the ileum to more moderate in the jejunum and caecum (see radiance scale bar for comparison). Intestines were cut into 12 segments and the luminescence of each segment was recorded. b, qPCR analysis of intestinal segments was performed in triplicate and plotted against the respective luminescence measurements. Regression analysis found robust correlation of tissue luminescence and PCR for parasite DNA, with r2 = 0.8. c, Mice were infected with 10,000 UGA2 FLuc oocysts, and 7 days after infection animals were treated daily for a week with vehicle or 10 mg per kg (body weight) KDU731. Whole-animal imaging during the treatment period is shown in Fig. 2g. Faecal oocyst load was determined by measuring parasite DNA by qPCR in faeces pooled from a cage of five mice. Error bars, s.d.