[PDF][PDF] Noncanonical autophagy is required for type I interferon secretion in response to DNA-immune complexes

J Henault, J Martinez, JM Riggs, J Tian, P Mehta… - Immunity, 2012 - cell.com
J Henault, J Martinez, JM Riggs, J Tian, P Mehta, L Clarke, M Sasai, E Latz, MM Brinkmann
Immunity, 2012cell.com
Summary Toll-like receptor-9 (TLR9) is largely responsible for discriminating self from
pathogenic DNA. However, association of host DNA with autoantibodies activates TLR9,
inducing the pathogenic secretion of type I interferons (IFNs) from plasmacytoid dendritic
cells (pDCs). Here, we found that in response to DNA-containing immune complexes (DNA-
IC), but not to soluble ligands, IFN-α production depended upon the convergence of the
phagocytic and autophagic pathways, a process called microtubule-associated protein …
Summary
Toll-like receptor-9 (TLR9) is largely responsible for discriminating self from pathogenic DNA. However, association of host DNA with autoantibodies activates TLR9, inducing the pathogenic secretion of type I interferons (IFNs) from plasmacytoid dendritic cells (pDCs). Here, we found that in response to DNA-containing immune complexes (DNA-IC), but not to soluble ligands, IFN-α production depended upon the convergence of the phagocytic and autophagic pathways, a process called microtubule-associated protein 1A/1B-light chain 3 (LC3)-associated phagocytosis (LAP). LAP was required for TLR9 trafficking into a specialized interferon signaling compartment by a mechanism that involved autophagy-related proteins, but not the conventional autophagic preinitiation complex, or adaptor protein-3 (AP-3). Our findings unveil a new role for nonconventional autophagy in inflammation and provide one mechanism by which anti-DNA autoantibodies, such as those found in several autoimmune disorders, bypass the controls that normally restrict the apportionment of pathogenic DNA and TLR9 to the interferon signaling compartment.
cell.com