Lipopolysaccharides (LPS), the main components of the surface of Gram(-) bacteria, are recognized by the immune system as a marker of bacterial invasion. LPS stimulates the production of several inflammatory mediators thus activating the immune response. Drugs able to block the action of LPS could attenuate inflammation limiting damage to host tissues. An example of such molecules are Cationic Antimicrobial Peptides (CAMPs), essential components of the natural immune response. The aim of the project was the identification and characterization of new CAMPs able to neutralize the pro-inflammatory activity of the LPS of P. aeruginosa CF clinical strains. It was expected to identify two types of human peptides: (a) peptides able to bind with very high affinity LPS, which could be used as LPS-scavengers (neutralizing effect) and (b) cytokine-like peptides which could be used as anti-inflammatory and immunostimulating drugs.