AN OSTEOADSORPTIVE FLUOROGENIC SUBSTRATE OF CATHEPSIN K FOR IMAGING OSTEOCLAST ACTIVITY AND MIGRATION

摘要

In certain embodiments osteoadsorptive fluorogenic substrates of cathepsin K (or other proteases) are provided. Utilizing a bisphosphonate targeting moiety, the fluorogenic substrates provide effective bone-targeted protease sensor(s). In certain embodiments the “probes” comprise cleavable fluorophore-quencher pair linked by a cathepsin K (or other protease) peptide substrate and tethered to a bisphosphonate. Unlike existing probes that are cleared within a few days in vivo, the probes described herein (e.g., OFS-1) allow for monitoring resorption over the course of longer time periods with a single dose.