Novel Anti-bacterial Activities of β-defensin 1 in Human Platelets: Suppression of Pathogen Growth and Signaling of Neutrophil Extracellular Trap Formation

• DOI: 10.1371/journal.ppat.1002355
• Publication Date: 2011-11-10T21:45:05Z
• Authors: Bjoern F. Kraemer; Robert A. Campbell; Hansjörg Schwertz; Mark J. Cody; Zechariah Franks; Neal D. Tolley; Walter H. A. Kahr; Stephan Lindemann; Peter Seizer; Christian C. Yost; Guy A. Zimmerman; Andrew S. Weyrich
• Keywords: Neutrophil Extracellular Traps

Human β-defensins (hBD) are antimicrobial peptides that curb microbial activity. Although hBD's primarily expressed by epithelial cells, we show human platelets express hBD-1 has both predicted and novel antibacterial activities. We observed activated surround Staphylococcus aureus (S. aureus), forcing the pathogens into clusters have a reduced growth rate compared to S. alone. Given microbicidal activity of β-defensins, determined whether hBD family members were present in found mRNA protein for hBD-1. also established resided extragranular cytoplasmic compartments platelets. Consistent with this localization pattern, agonists elicit granular secretion did not readily induce release. Nevertheless, released when they stimulated α-toxin, product permeabilizes target cells. Platelet-derived significantly impaired clinical strains aureus. induced robust neutrophil extracellular trap (NET) formation polymorphonuclear leukocytes (PMNs), which is function was previously identified. Taken together, these data demonstrate previously-unrecognized component displays classic and, addition, signals PMNs extrude DNA lattices capture kill bacteria.