Enhanced in vivo Optical Imaging of the Inflammatory Response to Acute Liver Injury in C57BL/6 Mice Using a Highly Bright Near-Infrared BODIPY Dye

Abstract

Delving deeper is possible in whole-body in vivo imaging using a super-bright membrane-targeting BODIPY dye (BD). The dye was used to monitor homing of ex vivo fluorescently labelled neutrophils to an injured liver of dark-pigmented C57BL/6 mice. In vivo imaging system (IVIS) data conclusively showed an enhanced signal intensity and a higher signal-to-noise ratio in mice receiving neutrophils labelled with the BD dye relative to those labelled with a gold standard dye at 2 h post in vivo administration of fluorescently labelled cells. Fluorescence-activated cell sorting (FACS) confirmed that BD is nontoxic, and an exceptional cell labelling dye that opens up precision deep-organ in vivo imaging of inflammation in mice routinely used for biomedical research. The origin of enhanced performance is identified with the molecular structure and the distinct localisation of the dye within cells that enable remarkable changes in its optical parameters.

Keywords: BODIPY; cell sorting; fluorescence; in vivo imaging; liver.