Effect of pre-conditioning on homing of MSCs in ischemic renal tissue. Homing of pre-conditioned MSCs in ischemic kidney tissue was assessed by tracking the CM-Dil positive cells under fluorescence microscope. The tissues were stained with actin (green), CM-Dil in red and nuclei were stained with DAPI (blue). Extensive homing of the CM-Dil positive MSCs was observed in SNAP pre-conditioned group (A) while a limited number of CM-Dil positive cells were observed in non pre-conditioned MSCs group (B). Whereas fewer MSCs were observed in SNAP/methylne blue and methylene blue only treated groups relative to the SNAP pre-conditioned group (C &D), magnification = 200x. E is graphical presentation of cell homing.