Type I interferon induction is detrimental during infection with the Whipple's disease bacterium, Tropheryma whipplei

Archive ouverte

Al Moussawi, Khatoun | Ghigo, Eric | Kalinke, Ulrich | Alexopoulou, Lena | Mege, Jean-Louis | Desnues, Benoit

Edité par CCSD ; Public Library of Science -

International audience. Macrophages are the first line of defense against pathogens. Upon infection macrophages usually produce high levels of proinflammatory mediators. However, macrophages can undergo an alternate polarization leading to a permissive state. In assessing global macrophage responses to the bacterial agent of Whipple's disease, Tropheryma whipplei, we found that T. whipplei induced M2 macrophage polarization which was compatible with bacterial replication. Surprisingly, this M2 polarization of infected macrophages was associated with apoptosis induction and a functional type I interferon (IFN) response, through IRF3 activation and STAT1 phosphorylation. Using macrophages from mice deficient for the type I IFN receptor, we found that this type I IFN response was required for T. whipplei-induced macrophage apoptosis in a JNK-dependent manner and was associated with the intracellular replication of T. whipplei independently of JNK. This study underscores the role of macrophage polarization in host responses and highlights the detrimental role of type I IFN during T. whipplei infection.

Suggestions

Du même auteur

Defining causality in emerging agents of acute bacterial diarrheas: a step beyond the Koch’s postulates

Archive ouverte | Desnues, Benoit | CCSD

International audience. Diarrheal illnesses account for significant morbidity and mortality worldwide. Most cases of diarrhea are caused by bacteria, viruses or parasites. Advances in molecular biology and epidemiol...

New insights into Whipple’s disease and Tropheryma whipplei infections

Archive ouverte | Desnues, Benoit | CCSD

International audience

An Experimental Mouse Model to Establish Tropheryma whipplei as a Diarrheal Agent

Archive ouverte | Al Moussawi, Khatoun | CCSD

International audience

Chargement des enrichissements...