Green Cathepsin B Assay by Immunochemistry Technologies LLC

Cathepsins are a group of protease enzymes typically found in the lysosome. Cathepsin B plays important roles in many cellular functions (like intracellular protein degradation, antigen processing, etc.). Elevated cathepsin activity is associated with many disease states such as cancer, Alzheimer’s disease, and so on.

The Green Cathepsin B Assay contains Rhodamine 110 Cathepsin B Substrate, which is a non-cytotoxic and cell membrane permeant substrate that fluoresces green upon cleavage by active cathepsins. To use Rhodamine 110-(RR)2, add the substrate directly to the cell culture medium, incubate, and analyze. Because the substrate is cell permeant, it easily penetrates the cell membrane and the membranes of the internal cellular organelles – no lysis or permeabilization steps are required. If active cathepsin enzymes are present, the quenched Rhodamine 110-(RR)2 substrate is cleaved, resulting in an increase in green fluorescence signal. Samples can be analyzed by flow cytometry or fluorescence microscopy. Hoechst 33342 is included in the kit to label nuclei.