Xenolight d luciferin potassium salt bioluminescent substrate

All bioluminescence measurements were performed using an IVIS Lumina system (Xenogen, Xenogen, Alameda, CA, USA) (field of view D (12.5 cm); F/stop 1; medium binning) and analyzed using Living Image software (Xenogen, Alameda, CA, USA) (Living Image^® 4.5.2.18424). XenoLight D-Luciferin Potassium Salt Bioluminescent Substrate (PerkinElmer, Waltham, MA, USA, #1227991) was dissolved at 30 mg/mL in PBS and 30 microliters were added directly onto the CAM (not on the tumor tissue). Assuming an average egg weight of 50–55 g, this equaled a D-Luciferin dose of 16–18 mg/kg. Bioluminescence was measured after 20 min (exposure time: 15 s; maximum 4 eggs in one measurement), as pilot experiments (see Figure S8) had shown that, at this time, saturating substrate delivery to CAM tumors was reached, yielding stable luminescence signals. When measurements were performed on multiple days, fresh D-Luciferin substrate was administered each time.

P. berghei parasitemia was determined in blood collected from the mouse tail using the Firefly Luciferase Assay Kit 2.0 (Biotium, Fremont, CA, USA), according to the manufacturer’s instructions. In vivo liver infection was quantified by imaging using XenoLight D-Luciferin - Potassium Salt Bioluminescent Substrate (PerkinElmer, Waltham, MA, USA) and the IVIS Lumina Imaging System (Caliper LifeSciences, Waltham, MA, USA).