title: Immunolocalization of NLRP3 Inflammasome in Normal Murine Airway Epithelium and Changes following Induction of Ovalbumin-Induced Airway Inflammation.
abstract: Little is known about innate immunity and components of inflammasomes in airway epithelium. This study evaluated immunohistological evidence for NLRP3 inflammasomes in normal and inflamed murine (Balb/c) airway epithelium in a model of ovalbumin (OVA) induced allergic airway inflammation. The airway epithelium of control mice exhibited strong cytoplasmic staining for total caspase-1, ASC, and NLRP3, whereas the OVA mice exhibited strong staining for active caspase-1, with redistribution of caspase-1, IL-1β and IL-18, indicating possible activation of the NLRP3 inflammasome. Active caspase-1, NLRP3, and other inflammasome components were also detected in tissue eosinophils from OVA mice, and may potentially contribute to IL-1β and IL-18 production. In whole lung, inRNA expression of NAIP and procaspase-1 was increased in OVA mice, whereas NLRP3, IL-1β and IL-18 decreased. Some OVA-treated mice also had significantly elevated and tightly correlated serum levels of IL-1β and TNFα. In cultured normal human bronchial epithelial cells, LPS priming resulted in a significant increase in NLRP3 and II-lp protein expression. This study is the first to demonstrate NLRP3 inflammasome components in normal airway epithelium and changes with inflammation. We propose activation and/or luminal release of the inflammasome is a feature of allergic airway inflammation which may contribute to disease pathogenesis.
authors.affiliation: Centre for Inflammatory Disease Research (CIDR), The Basil Hetzel Institute for Translational Health Research, Woodville South, SA 5011, Australia.
authors.forename: Hai B
authors.initials: HB
authors.lastname: Tran
authors.forename: Martin D
authors.initials: MD
authors.lastname: Lewis
authors.forename: Lor Wai
authors.initials: LW
authors.lastname: Tan
authors.forename: Susan E
authors.initials: SE
authors.lastname: Lester
authors.forename: Leonie M
authors.initials: LM
authors.lastname: Baker
authors.forename: Jia
authors.initials: J
authors.lastname: Ng
authors.forename: Monica A
authors.initials: MA
authors.lastname: Hamilton-Bruce
authors.forename: Catherine L
authors.initials: CL
authors.lastname: Hill
authors.forename: Simon A
authors.initials: SA
authors.lastname: Koblar
authors.forename: Maureen
authors.initials: M
authors.lastname: Rischmueller
authors.forename: Richard E
authors.initials: RE
authors.lastname: Ruffin
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Wormald
authors.forename: Peter D
authors.initials: PD
authors.lastname: Zalewski
authors.forename: Carol J
authors.initials: CJ
authors.lastname: Lang