Fig. 1

Schematic illustration of experimental design. a Labeling of genetically modified MSCs with TAT-CPNPs. Aiming to screen genes that promote the targeting migratory ability of MSCs, Cxcr3, whose ligand was up-regulated in the CHS animal model, was selected as a candidate gene and transduced into MSCs with lentivirus. To visualize gene modified MSCs via NIR-II PA imaging, TAT-CPNPs with high absorbance at 1064 nm were fabricated to label modified MSCs. b Longitudinal PA imaging of non-inflamed or inflamed ears in the CHS mouse model for assessing the targeting migratory ability of TAT-CPNPs labelled MSCs. TAT-CPNPs labeled MSCs were intravenously delivered to CHS mice, PA imaging at 1064 nm of non-inflamed or inflamed ears were performed at different time points after injection. The accumulation within targeted tissues and extravasation of MSC^eGFP and MSC^Cxcr3 were analyzed