The human antimicrobial and chemotactic peptides LL-37 and α-defensins are expressed by specific lymphocyte and monocyte populations

We identified antibacterial components in human T and natural killer (NK) cells by using freshly isolated lymphocytes enriched for T and NK cells as starting material. After growing these lymphocytes for 5 days in the presence of interleukin (IL)–2, we isolated and characterized several antibacterial peptides/proteins from the supernatant—α-defensins (HNP 1-3), LL-37, lysozyme, and a fragment of histone H2B—although other active components were...