[Antimicrobial peptides/proteins--application to the therapy of sepsis].

Many antimicrobial peptides and proteins were discovered recently in various animals. Cecropins are insect-derived antimicrobial peptides which contain 35-39 amino acid residues. Magainins are amphibian-derived antimicrobial peptides with 21-27 amino acid residues. In mammals, defensins, 29-35 amino acid peptides, were identified in the granules of neutrophils and various epithelial cells. In addition, the granules of neutrophils in the mammal have been shown to have several antimicrobial proteins. Among them, bactericidal/permeability increasing protein (BPI) and cationic antimicrobial peptide-18 (CAP 18) have been found to have potent bactericidal activity against gram-negative bacteria and strong lipopolysaccharide-neutralizing function. The recombinant BPIs (recombinant BPI, 23-kDa N-terminal fragment of BPI, and lipopolysaccharide-binding protein-BPI fusion protein) and synthetic peptides derived from C-terminal of CAP 18 are now under investigation for the application to the therapy of sepsis or septic shock.