A Self-Immobilizing NIR Probe for Non-invasive Imaging of Senescence

Abstract

Cellular senescence, a process that arrests the cell cycle, is a cellular stress response to various stimuli and is implicated in aging and age-related diseases. However, the understanding of senescence in living organisms is insufficient, largely due to the scarcity of sensitive tools for the detection of cellular senescence in vivo. Herein, we describe the development of a self-immobilizing near-infrared (NIR) probe that can be activated by senescence-associated {beta}- Galactosidase (SA-{beta}-Gal), a widely accepted senescence marker. The NIR fluorophore is turned on in the presence of SA-{beta}-Gal, and the self-immobilizing group, based on quinone methide chemistry, retains the fluorescence signal to the site of activation. This strategy significantly improves the sensitivity of the probe from the one we developed before. We demonstrate the non-invasive imaging of drug-induced senescence in mice models.