In vivo and ex vivo BLI was performed on IVIS50 (PerkinElmer, Waltham, MA) as previously described (20 (link)). Total photon flux (photons/sec) was measured from fixed regions of interest (ROIs) over entire mouse or manually around ex vivo organs using Living Image 2.6, as indicated. Mice with outstanding chest BLI intensity indicative of a failed intracardiac injection or with ineffective D-luciferin administration were excluded from all analyses. Investigators were blinded to treatment groups during all BLI analyses.