Neutrophil extracellular traps: casting the NET over pathogenesis.

Department of Bacteriology, Swedish Institute for Infectious Disease Control Nobelsväg 18, SE-171 82 Solna, Solna, Sweden.
Current Opinion in Microbiology (Impact Factor: 7.22). 03/2007; 10(1):52-6. DOI: 10.1016/j.mib.2006.12.005
Source: PubMed

ABSTRACT Neutrophil extracellular traps (NETs) are considered to be part of the human innate immunity because they trap and kill pathogens. NETs are formed by activated neutrophils and consist of a DNA backbone with embedded antimicrobial peptides and enzymes. They are involved in host defense during pneumococcal pneumonia, streptococcal necrotizing fasciitis, appendicitis and insemination. Recently, bacterial virulence factors that counteract NETs have been identified. These include the degradation of the NET-backbone by DNases enabling the liberation of bacteria from NETs, as well as capsule formation, which reduces bacterial trapping. Furthermore, pathogens can resist NET-mediated killing by adding positive charge to their cell surface.

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