Limit of detection <i>in vivo</i>.

<p>(<b>A</b>) Six sets of three BALB/c mice were inoculated i.p. with either 20, 100, 500, 5000, or 50000 bloodstream form <i>T.b. brucei</i> GVR35 clone VSL2. An additional set of three mice was inoculated with 30000 non-transformed parasites (WT). All of the IVIS Lumina images were acquired using large binning, 5 minute exposures, 15 minutes after infection and 10 minutes after administration of luciferin (150 mg kg⁻¹). It was possible to visualise as few as 100 parasites in the intra-peritoneal space. (<b>B</b>) A dose response curve generated from the <i>in vivo</i> limit of detection data. Mean abdominal bioluminescence was recorded from each group. Linear regression analysis shows a very strong positive correlation between bioluminescence and parasite inoculum (R²>0.99). Dotted line indicates mean bioluminescence plus two standard deviations, from mice infected with wild type parasites.