Cationic antimicrobial peptides and their multifunctional role in the immune system.
Many species of life contain cationic antimicrobial peptides as components of their immune systems. The antimicrobial activity of these peptides has been studied extensively, and many peptides have a broad spectrum of activity not only against gram-negative and gram-positive bacteria but also against antibiotic-resistant bacteria, fungi, viruses, and parasites. Such cationic antimicrobial peptides can also act in synergy with host molecules, such as other cationic peptides and proteins, lysozyme, and also conventional antibiotics, to kill microbes. It has been found that certain peptides are produced in large quantities at sites of infection/inflammation, and their expression can be induced by bacterial products such as endotoxic lipopolysaccharide (LPS) and proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha). These peptides often have a high affinity for bacterial products, such as LPS, allowing them to modulate the host response and reduce the inflammatory response in sepsis. More recently, they have been found to interact directly with host cells to modulate the inflammatory process and innate defenses.
Scott
M G
MG
Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada.
Hancock
R E
RE
D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000935:Antifungal Agents / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology* / Q000627:therapeutic use; D000998:Antiviral Agents / Q000494:pharmacology; D004357:Drug Synergism; D006801:Humans; D008969:Molecular Sequence Data; D018805:Sepsis / Q000276:immunology / Q000473:pathology / Q000517:prevention & control
D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D023181:Antimicrobial Cationic Peptides; D000998:Antiviral Agents