Intracellular Survival of Leishmania major Depends on Uptake and Degradation of Extracellular Matrix Glycosaminoglycans by Macrophages.
Leishmania parasites replicate within the phagolysosome compartment of mammalian macrophages. Although Leishmania depend on sugars as a major carbon source during infections, the nutrient composition of the phagolysosome remains poorly described. To determine the origin of the sugar carbon source in macrophage phagolysosomes, we have generated a N-acetylglucosamine acetyltransferase (GNAT) deficient Leishmania major mutant (∆gnat) that is auxotrophic for the amino sugar, N-acetylglucosamine (GlcNAc). This mutant was unable to grow or survive in ex vivo infected macrophages even when macrophages were cultivated in presence of exogenous GlcNAc. In contrast, the L. major ∆gnat mutant induced normal skin lesions in mice, suggesting that these parasites have access to GlcNAc in tissue macrophages. Intracellular growth of the mutant in ex vivo infected macrophages was restored by supplementation of the macrophage medium with hyaluronan, a GlcNAc-rich extracellular matrix glycosaminoglycan. Hyaluronan is present and constitutively turned-over in Leishmania-induced skin lesions and is efficiently internalized into Leishmania containing phagolysosomes. These findings suggest that the constitutive internalization and degradation of host glycosaminoglycans by macrophages provides Leishmania with essential carbon sources, creating a uniquely favorable niche for these parasites.
The Department of Biochemistry and Molecular Biology and the Bio21 Institute of Molecular Science and Biotechnology, University of Melbourne, Parkville, Victoria, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia.
Thomas
T
Naderer
The Department of Biochemistry and Molecular Biology and the Bio21 Institute of Molecular Science and Biotechnology, University of Melbourne, Parkville, Victoria, Australia.
Joanne
J
Heng
The Department of Biochemistry and Molecular Biology and the Bio21 Institute of Molecular Science and Biotechnology, University of Melbourne, Parkville, Victoria, Australia.
Eleanor C
EC
Saunders
The Department of Biochemistry and Molecular Biology and the Bio21 Institute of Molecular Science and Biotechnology, University of Melbourne, Parkville, Victoria, Australia.
Joachim
J
Kloehn
Metabolomics Australia, Bio21 Institute of Molecular Science and Biotechnology, University of Melbourne, Parkville, Victoria, Australia.
Thusitha W
TW
Rupasinghe
Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia.
Tracey J
TJ
Brown
The Department of Biochemistry and Molecular Biology and the Bio21 Institute of Molecular Science and Biotechnology, University of Melbourne, Parkville, Victoria, Australia.
Malcolm J
MJ
McConville
D000117:Acetylglucosamine / Q000378:metabolism; D000123:Acetyltransferases / Q000235:genetics / Q000378:metabolism; D000818:Animals; D002470:Cell Survival; D002478:Cells, Cultured; D005109:Extracellular Matrix / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D017353:Gene Deletion; D006025:Glycosaminoglycans / Q000378:metabolism*; D006790:Host-Parasite Interactions; D006868:Hydrolysis; D007700:Kinetics; D018320:Leishmania major / Q000235:genetics / Q000254:growth & development / Q000276:immunology / Q000502:physiology*; D007894:Leishmania mexicana / Q000235:genetics / Q000254:growth & development / Q000276:immunology / Q000502:physiology; D016773:Leishmaniasis, Cutaneous / Q000276:immunology / Q000378:metabolism / Q000469:parasitology / Q000473:pathology; D008247:Lysosomes / Q000276:immunology / Q000378:metabolism / Q000469:parasitology* / Q000473:pathology; D008264:Macrophages / Q000276:immunology / Q000378:metabolism / Q000469:parasitology* / Q000473:pathology; D008297:Male; D008807:Mice, Inbred BALB C; D010587:Phagocytosis; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism; D013045:Species Specificity; D013047:Specific Pathogen-Free Organisms
D006025:Glycosaminoglycans; D015800:Protozoan Proteins; D000123:Acetyltransferases; C020580:glucosamine acetyltransferase; D000117:Acetylglucosamine