Developing a far-red fluorogenic beta-galactosidase probe for senescent cell imaging and photoablation

A methylene blue (MB)-based beta-galactosidase (beta-gal) activatable molecule, Gal-MB, was developed for senescence imaging and light-triggered senolysis. When in contact with LacZ beta-gal or senescence-associated beta-gal (SA-beta-gal), the photoinsensitive Gal-MB becomes fluorescent. Gal-MB also offered selective phototoxicity toward LacZ beta-gal expressing cells and drug-induced senescent cells, which express SA-beta-gal, after light illumination at 665 nm.