Format

Send to

Choose Destination
EMBO J. 2019 Aug 29:e101365. doi: 10.15252/embj.2018101365. [Epub ahead of print]

Antibody and DNA sensing pathways converge to activate the inflammasome during primary human macrophage infection.

Author information

1
Protein and Nucleic Acid Chemistry Division, Medical Research Council, Laboratory of Molecular Biology, Cambridge, UK.
2
Centre for Immune Regulation (CIR), Department of Biosciences, University of Oslo, Oslo, Norway.
3
CIR and Department of Immunology, Oslo University Hospital Rikshospitalet, Oslo, Norway.
4
Department of Pharmacology, Institute of Clinical Medicine, Oslo University Hospital, University of Oslo, Oslo, Norway.

Abstract

Inflammasomes are potent innate immune signalling complexes that couple cytokine release with pro-inflammatory cell death. However, pathogens have evolved strategies to evade this cell autonomous system. Here, we show how antibodies combine with innate sensors in primary human macrophages to detect viral infection and activate the inflammasome. Our data demonstrate that antibody opsonisation of virions can activate macrophages in multiple ways. In the first, antibody binding of adenovirus causes lysosomal damage, activating NLRP3 to drive inflammasome formation and IL-1β release. Importantly, this mechanism enhances virion capture but not infection and is accompanied by cell death, denying the opportunity for viral replication. Unexpectedly, we also find that antibody-coated viruses, which successfully escape into the cytosol, trigger a second system of inflammasome activation. These viruses are intercepted by the cytosolic antibody receptor TRIM21 and the DNA sensor cGAS. Together, these sensors stimulate both NLRP3 inflammasome formation and NFκB activation, driving dose-dependent IL-1β and TNF secretion, without inducing cell death. Our data highlight the importance of cooperativity between multiple sensing networks to expose viruses to the inflammasome pathway, which is particularly important for how our innate immune system responds to infection in the presence of pre-existing immunity.

KEYWORDS:

TRIM21; adenovirus; antibody; inflammasome; macrophage

PMID:
31468569
DOI:
10.15252/embj.2018101365
Free full text

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center