The mouse monoclonal antibody recognizes human Trypsin, a 24 kDa enzyme and a member of the serine proteinase family. It is produced in the pancreas as an inactive precursor trypsinogen. The active enzyme is located in the gastrointestinal tract where it degrades proteins to large peptides. Trypsin predominantly cleaves proteins at the carboxyl side of the amino acids lysine and arginine. A common trypsin substrate is chymotrypsinogen which is cleaved to produce active chymotrypsin. High levels of immunoreactive trypsin in the bloodstream can indicate pancreatic malfunction and this indicator is used to screen for and diagnose Cystic Fibrosis.