Anti-CST5 antibodies are used in the immunodetection of the protein cystatin D. In humans, the canonical protein has a reported length of 142 amino acid residues and a mass of 16.1 kDa. It has been described to be a secreted protein. It is reported to be expressed in submandibular and sublingual saliva but not in parotid saliva. It is a member of the Cystatin protein family. Synonyms for this target antigen include cystatin 5 and cysteine-proteinase inhibitor. CST5 gene orthologs have been reported in the mouse, rat and chimpanzee species. ELISA, Western Blot, and Immunofluorescence are common applications for CST5 antibodies.