Autophagosome-independent essential function for the autophagy protein Atg5 in cellular immunity to intracellular pathogens.
The physiologic importance of autophagy proteins for control of mammalian bacterial and parasitic infection in vivo is unknown. Using mice with granulocyte- and macrophage-specific deletion of the essential autophagy protein Atg5, we show that Atg5 is required for in vivo resistance to the intracellular pathogens Listeria monocytogenes and Toxoplasma gondii. In primary macrophages, Atg5 was required for interferongamma (IFN-gamma)/LPS-induced damage to the T. gondii parasitophorous vacuole membrane and parasite clearance. While we did not detect classical hallmarks of autophagy, such as autophagosomes enveloping T. gondii, Atg5 was required for recruitment of IFN-gamma-inducible p47 GTPase IIGP1 (Irga6) to the vacuole membrane, an event that mediates IFN-gamma-mediated clearance of T. gondii. This work shows that Atg5 expression in phagocytic cells is essential for cellular immunity to intracellular pathogens in vivo, and that an autophagy protein can participate in immunity and intracellular killing of pathogens via autophagosome-independent processes such as GTPase trafficking.
Zhao
Zijiang
Z
Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA.
Fux
Blima
B
Goodwin
Megan
M
Dunay
Ildiko R
IR
Strong
David
D
Miller
Brian C
BC
Cadwell
Ken
K
Delgado
Monica A
MA
Ponpuak
Marisa
M
Green
Karen G
KG
Schmidt
Robert E
RE
Mizushima
Noboru
N
Deretic
Vojo
V
Sibley
L David
LD
Virgin
Herbert W
HW
D000818:Animals; D001343:Autophagy; D000071187:Autophagy-Related Protein 5; D002478:Cells, Cultured; D054884:Host-Pathogen Interactions; D006801:Humans; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000276:immunology; D008089:Listeria monocytogenes / Q000502:physiology*; D008088:Listeriosis / Q000276:immunology* / Q000382:microbiology; D008247:Lysosomes / Q000276:immunology / Q000469:parasitology; D008264:Macrophages / Q000276:immunology* / Q000469:parasitology; D051379:Mice; D008808:Mice, Inbred CBA; D018345:Mice, Knockout; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000276:immunology*; D015398:Signal Transduction; D014122:Toxoplasma / Q000502:physiology*; D014123:Toxoplasmosis / Q000276:immunology* / Q000469:parasitology
C495773:Atg5 protein, mouse; D000071187:Autophagy-Related Protein 5; D008869:Microtubule-Associated Proteins; D007371:Interferon-gamma