Vanin-1 controls granuloma formation and macrophage polarization in Coxiella burnetii infection.
Q fever is caused by Coxiella burnetii, a bacterium that survives in MPhi. Vanin-1 is a membrane-anchored pantetheinase that controls tissue inflammation. Consequently, Vanin-1-deficient mice represent a unique mouse model in which stress-induced inflammation is limited by the reaction of resident tissue cells. To investigate the contribution of host tissues in the control of a bacterial infection, we infected Vanin-1-deficient mice with C. burnetii. Mortality and morbidity of mice were not affected. The lack of Vanin-1 had no effect on C. burnetii clearance but decreased the formation of granulomas in spleen and liver. Granuloma formation depends upon MPhi recruitment and activation in these tissues. Whereas the former was slightly impaired in mutant mice, the lack of Vanin-1 significantly affected the activation pattern of BM-derived MPhi stimulated by C. burnetii. While their microbicidal activity against C. burnetii was moderately impaired, they exhibited decreased inducible nitric oxide synthase (iNOS) and MCP-1 gene expression, and increased IL-10 and arginase expression. In liver from mutant mice, increased arginase expression and decreased expression of MCP-1 and iNOS were reminiscent of MPhi data. These results suggest a role of Vanin-1 in granuloma formation in response to C. burnetii by skewing MPhi activation toward an M2 program.
Meghari
Soraya
S
Unité des Rickettsies, CNRS UMR 020, Institut Fédératif de Recherche 48, Université de la Méditerranée, Marseille, France.
Berruyer
Carole
C
Lepidi
Hubert
H
Galland
Franck
F
Naquet
Philippe
P
Mege
Jean-Louis
JL
D000581:Amidohydrolases; D000818:Animals; D015815:Cell Adhesion Molecules / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D016764:Cell Polarity / Q000276:immunology*; D016997:Coxiella burnetii / Q000276:immunology*; D005260:Female; D058851:GPI-Linked Proteins; D006099:Granuloma / Q000235:genetics / Q000276:immunology* / Q000378:metabolism* / Q000382:microbiology; D017737:Macrophages, Peritoneal / Q000276:immunology / Q000378:metabolism* / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D011778:Q Fever / Q000235:genetics / Q000276:immunology* / Q000378:metabolism* / Q000382:microbiology
D015815:Cell Adhesion Molecules; D058851:GPI-Linked Proteins; D000581:Amidohydrolases; C022314:pantetheinase