KOR

e-Article

Neutrophil Caspase-11 Is Required for Cleavage of Caspase-1 and Secretion of IL-1β in Aspergillus fumigatus Infection.
Document Type
Article
Source
Journal of Immunology. 11/1/2018, Vol. 201 Issue 9, p2767-2775. 9p.
Subject
*NEUTROPHILS
*CASPASES
*ASPERGILLUS fumigatus
*MACROPHAGES
*BACTERIAL diseases
*INTERLEUKIN-1
Language
ISSN
0022-1767
Abstract
Neutrophils are an important source of IL-1β secretion in bacterial infections, where they infiltrate affected tissues in log-fold higher numbers than macrophages. Neutrophils also have functional NLRP3 and NLRC4 inflammasomes that can process pro- IL-1β to the bioactive 17-kDa form. In the current study, we examined the role of IL-1β in response to corneal infection with the filamentous fungus Aspergillus fumigatus and found that neutrophils were the predominant source of bioactive IL-1β in the cornea. We also observed that caspase-11-/- mice exhibit the same susceptibility phenotype as IL-1β-/-, ASC-/-, NLRP3-/-, and caspase-1-/- mice, with impaired neutrophil recruitment to infected corneas and increased hyphal growth. We further demonstrate that caspase-11 is required for caspase-1 activation and IL-1β processing during infection. In vitro, we show that caspase-11 is regulated by the common type I IFN receptor (IFNAR) through JAK-STAT signaling and that caspase-11 is required for speck formation and caspase-1 activity. Aspergillus spores (conidia) stimulate IL-1β processing and secretion in neutrophils activation of Dectin-1 and signaling through the Raf1 kinase/MEKK rather than the spleen tyrosine kinase pathway. Collectively, these findings reveal unexpected regulation of IL-1β production by neutrophils in response to pathogenic fungi. [ABSTRACT FROM AUTHOR]