Pyroptosis triggers pore-induced intracellular traps (PITs) that capture bacteria and lead to their clearance by efferocytosis

• DOI: 10.1084/jem.20151613
• Publication Date: 2016-08-29T14:07:24Z
• Authors: Ine Jorgensen; Yue Zhang; Bryan A. Krantz; Edward A. Miao
• Keywords: efferocytosis; Pyroptosis; Lead (geology)

Inflammasomes activate caspase-1 in response to cytosolic contamination or perturbation. This inflammatory caspase triggers the opening of GSDMD pore plasma membrane, resulting lytic cell death called pyroptosis. We had previously assumed that pyroptosis releases intracellular bacteria extracellular space. Here, we find viable instead remain trapped within cellular debris pyroptotic macrophages. trapping appears be an inevitable consequence how osmotic lysis ruptures and may also apply necroptosis some forms nonprogrammed necrosis. Although membrane tears release soluble contents, they are small enough retain organelles bacteria. call this structure pore-induced trap (PIT), which is conceptually parallel neutrophil (NET). The PIT coordinates innate immune responses via complement scavenger receptors drive recruitment efferocytosis by neutrophils. Ultimately, secondary phagocyte kills Hence, caspase-1-driven a multifaceted defense against facilitated pathogen debris. Bona fide bacterial pathogens, such as Salmonella, must prevent delay avoid being subsequently killed