Fig. 4
Biodistribution assay after ECFCs administration to CLTI mice. A In vivo scan on day 1 (top) and day 3 (bottom) after intramuscular (IM + , n:4) or intravenous (IV + , n:4) administration of 106 DiR pre-labeled ECFCs to CLTI mice. A set of mice injected via tail vein (IV-, n:1) or intramuscular (IM-, n:1) with 0.2 µM DiR solution as residual DiR negative controls were included, together with a Negative Control (with 1·106 unlabeled ECFCs) to consider background signals during the in vivo and ex vivo scans. B Fluorescence intensity (FI) per area (k counts/mm2) on days 1 and 3 after IM (top) or IV (bottom) injection of 1·106 DiR pre-labeled ECFCs. C Cell number estimation per area (cells/cm2) of in vivo scans on days 1 and 3 of IM (left) and IV administration (right) ECFCs. D Ex vivo scans from spleen, kidneys, lungs, liver and hind limbs at day 3 after ECFCs IM or IV transplantation. E Fluorescence intensity (FI) per area (k counts/mm2) of organs after performing an ex vivo scan. F Cell number estimation per area (cells/cm2) of ex vivo scans. G Number of cells per tissue mg calculated after human-specific Alu gene amplification by qPCR in liver, spleen, lungs, kidneys and back muscle tissue at day 3