Application of activity-based probes to interrogate the contribution of cathepsin X to dendritic cells

Abstract

Cathepsin X/Z/P (Cat X) is a lysosomal cysteine protease that exhibits mono-carboxypeptidase activity. Increased cathepsin X expression is associated with cancer and inflammation; however, its roles in normal physiology are poorly understood. Cathepsin X is highly expressed by antigen-presenting cells such as dendritic cells (DCs). DCs undergo functional changes upon agonism of pattern recognition receptors (e.g., Toll-like receptors) by pathogen-associated molecular patterns (e.g., bacterial DNA – CpG). Mature DCs can secrete cytokines and present antigens to activate adaptive immunity. We hypothesised that cathepsin X contributes to DC function. Using activity-based probes, immunoblottin..