Porcine antimicrobial peptides: New prospects for ancient molecules of host defense

Antimicrobial peptides (AMPs) are small, endogenous, polycationic molecules that constitute a ubiquitous and significant component of innate immunity. These natural antibiotics have broad microbicidal activity against various bacteria, fungi, and enveloped viruses. Because most AMPs kill bacteria by physical disruption of cell membranes, which may prevent microorganisms from developing resistance against these agents, they are being explored as possible alternatives to conventional antibiotics. Pigs, like many other mammals, produce an impressive array of AMPs, which are synthesized predominantly by host leukocytic phagocytes or mucosal epithelial cells. Currently, more than a dozen distinct porcine AMPs have been identified and a majority belongs to the cathelicidin family. This review briefly summarizes recent advances in porcine AMP research with an emphasis on the diverse biological functions of each peptide. Mechanisms of action of these AMPs and their role in the resistance to infections are considered. Finally, the current status of pharmaceutical and agricultural uses of AMPs as well as future prospects for their application in the food animal industry is discussed. pig / antimicrobial peptide / cathelicidin / defensin / innate immunity Rsum -Peptides antimicrobiens porcins : nouvelles perspectives pour d'anciennes molcules de dfense de l'hte. Les peptides antimicrobiens sont de petites molcules endognes, polycationiques, qui reprsentent un lment important et ubiquitaire des dfenses immunes naturelles. Ces antibiotiques naturels ont un effet antimicrobien large spectre, la fois contre des bactries, des moisissures et des virus envelopps. Comme la plupart de ces peptides antimicrobiens tuent les bactries par altration physique de leur membrane, ce qui peut viter le dveloppement de souches microbiennes rsistantes ces agents, ils reprsentent des alternatives possibles l'emploi des antibiotiques classiques. Le porc, comme de nombreux autres mammifres, produit une gamme importante de peptides antimicrobiens, synthtiss pour l'essentiel par les leucocytes activit phagocytaire, ou par les cellules pithliales des muqueuses. Il y a actuellement plus d'une douzaine de peptides antimicrobiens identifis chez le porc, dont la majorit fait partie de la famille des cathlicidines. Cet article