Use of fluorescent imaging to investigate pathological protease activity.

Proteases play pivotal roles in the normal function of cells. In addition, the expression and activity of proteases are significantly upregulated in several pathologies, including cancer, arthritis and atherosclerosis, and hence they can be considered to be biological markers for these pathologies. The hydrolyzing activity of proteases has been used to generate a variety of fluorescent imaging reagents, the design and utility of which are reviewed here. The use of imaging reagents to visualize protease activity allows for improved detection of various pathologies as well as the ability to monitor the efficacy of therapies in vivo and provide molecular information regarding the nature of the pathology.