{
  "id": 8828619,
  "title": "Inflammasome Activation and IL-1β Release in Alveolar Macrophages Infected with Pseudomonas aeruginosa is Reduced in Hypoxia",
  "url": "https://urgent.news/2026/09/20/inflammasome-activation-and-il-1-release-in-alveolar-macrophages",
  "topic": "science",
  "section": "Science",
  "published": "2026-09-20T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.09.14.750667v1?rss=1"
  },
  "original_language": "en",
  "account": "Pseudomonas aeruginosa, a crucial factor in acute or chronic airway infections, exhibits genetic and environmental adaptations to influence its virulence during airway infections. This bacterium can fine-tune its type III secretion system (T3SS) and other virulence factors in response to selective pressures during infection. Many patient groups, such as those with cystic fibrosis (CF), are predisposed to P. aeruginosa infections due to the presence of hypoxic areas and thick mucus in their airways. Resident alveolar macrophages (AMs) play a crucial role in coordinating immune responses against P. aeruginosa by producing proinflammatory cytokines like IL-1β. Upon infection with lab strains of P. aeruginosa, AMs detect the T3SS and activate the NLRC4 inflammasome, leading to IL-1β release. However, the response of AMs to clinical CF isolate DH1137 of P. aeruginosa has not been previously explored. In this study, the characteristics of DH1137 were identified, revealing a downregulated but functional T3SS, adaptation to hypoxic conditions, and significant production of inflammasome cytokines IL-1β and IL-1 during lung infection in a CF mouse model. AMs were primed for inflammasome gene expression through LPS stimulation, and upon infection with DH1137, these cells released IL-1β. Remarkably, hypoxia during DH1137 infection led to significantly reduced inflammasome activation compared to normoxia. These findings illuminate a novel mechanism by which P. aeruginosa might evade immune detection in tissue-resident lung macrophages within the context of CF.",
  "summary": "Pseudomonas aeruginosa is an important agent of acute or chronic airway infections. A complex set of genetic and environmental factors determine the outcome of a P. aeruginosa airway infection. P. aeruginosa can undergo genetic adaptation to fine tune the expression of a type III secretion system (T3SS) and other virulence factors in response to selective pressures encountered during infection.…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}