Human Cathepsin C/DPPI Alexa Fluor® 488-conjugated Antibody

Cathepsin C, also known as dipeptidyl-peptidase I (DPPI), is a cysteine protease of the papain family (1). Cathepsin C sequentially removes dipeptides from the free N-termini of proteins and peptides. It has broad specificity except that it does not cleave a basic amino acid (Arg or Lys) in the N-terminal position or Pro on either side of the scissle bond. It requires halide ions for activity. The pro form contains a pro peptide and a catalytic region, which can be further processed into heavy/ alpha and light/ beta chains that are linked by a disulfide bond. It is broadly distributed. Cathepsin C plays a role in the lysosomal degradation. It also functions as a key enzyme in the activation of granule serine proteases in cytotoxic T lymphocytes and natural killer cells (granzymes A and B), mast cells (tryptase and chymase), and neutrophils (Cathepsin G and elastase) by removing their N-terminal activation dipeptides (2). Loss of function mutations in the Cathepsin C gene result in periodontal disease and palmoplantar keratosis (3).