ATG16L1 deficiency in macrophages drives clearance of uropathogenic E. coli in an IL-1β-dependent manner

Mucosal Immunol. 2015 Nov;8(6):1388-99. doi: 10.1038/mi.2015.7. Epub 2015 Feb 11.

Abstract

Urinary tract infections (UTIs) are frequent, commonly recurrent, and costly. Deficiency in a key autophagy protein, ATG16L1, protects mice from infection with the predominant bacterial cause of UTIs, Uropathogenic E. coli (UPEC). Here, we report that loss of ATG16L1 in macrophages accounts for this protective phenotype. Compared with wild-type macrophages, macrophages deficient in ATG16L1 exhibit increased uptake of UPEC and enhanced secretion of interleukin-1β (IL-1β). The increased IL-1β production is dependent upon activation of the NLRP3 inflammasome and caspase-1. IL-1β secretion was also enhanced during UPEC infection of ATG16L1-deficient mice in vivo, and inhibition of IL-1β signaling abrogates the ATG16L1-dependent protection from UTIs. Our results argue that ATG16L1 normally suppresses a host-protective IL-1β response to UPEC by macrophages.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Autophagy-Related Proteins
  • Blotting, Western
  • Carrier Proteins / genetics
  • Carrier Proteins / immunology*
  • Disease Models, Animal
  • Enzyme-Linked Immunosorbent Assay
  • Escherichia coli Infections / immunology*
  • Female
  • Flow Cytometry
  • Interleukin-1beta / immunology*
  • Macrophages / immunology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Polymerase Chain Reaction
  • Urinary Tract Infections / immunology*
  • Uropathogenic Escherichia coli / immunology

Substances

  • Atg16l1 protein, mouse
  • Autophagy-Related Proteins
  • Carrier Proteins
  • IL1B protein, mouse
  • Interleukin-1beta