Characterization of recombinant human HBP/CAP37/azurocidin, a pleiotropic mediator of inflammation-enhancing LPS-induced cytokine release from monocytes

Neutrophil-derived heparin-binding protein (HBP) is a strong chemoattractant for monocytes, We report here for the first time the expression of recombinant HBP. A baculovirus containing the human HBP cDNA mediated in insect cells the secretion of a 7-residue N-terminally extended HBP form (pro-HBP). Deletion of the pro-peptide-encoding cDNA sequence resulted in correctly processed HBP at the N-terminus. Electrospray mass spectrum analysis of recombinant HBP yielded a molecular weight of 27.237 +/- 3 amu. Consistent with this mass is a HBP form of 225 amino acids (mature part +3 amino acid C-terminal extension), The biological activity of recombinant HBP was confirmed by its chemotactic action towards monocytes, Furthermore, we have shown that recombinant HBP stimulates in a dose-dependent manner the lipopolysaccharide (LPS)-induced cytokine release from human monocytes.