The function of CPB2 (carboxypeptidase B2, Ensembl gene identifier ENSG00000080618) is as follows. Cleaves C-terminal arginine or lysine residues from biologically active peptides such as kinins or anaphylatoxins in the circulation thereby regulating their activities. Down-regulates fibrinolysis by removing C-terminal lysine residues from fibrin that has already been partially degraded by plasmin. .