Inhibition of human leukocyte elastase and cathepsin G by extended peptides and subunits derived from human C-reactive protein

Abstract

Extended peptides that derive from the primary sequence of the acute phase reactant C-reactive protein (CRP) are shown to inhibit in vitro the enzymatic activities of human leukocyte elastase (hLE) and human leukocyte cathepsin G (hCG), which are associated with the tissue damage that occurs during the course of several chronic inflammatory conditions. Major inhibitory activity was observed in the peptides CRP70–98 and CRP50–98 towards hLE (Ki=4.0μ M) and hCG (Ki=1.4 μM), respectively. In contrast to the inability of intact CRP pentamers to inhibit both enzymes, CRP subunits (monomers) inhibited hLE (3.0 μM) and hCG (3.6 μM) activity.