Investigation of the fungal communities in animal models of Inflammatory Bowel Diseases (IBD) showed a controversial role of and spp In health and disease. These conflicting observations could be ascribed to immunogenic differences among co-specific strains. To assess the relevance of intra-strains differences on yeast immunogenicity and impact on the microbiota, we screened and spp.
View Article and Find Full Text PDFDysregulated inflammasome activation contributes to respiratory infections and pathologic airway inflammation. Through basic and translational approaches involving murine models and human genetic epidemiology, we show here the importance of the different inflammasomes in regulating inflammatory responses in mice and humans with cystic fibrosis (CF), a life-threatening disorder of the lungs and digestive system. While both contributing to pathogen clearance, NLRP3 more than NLRC4 contributes to deleterious inflammatory responses in CF and correlates with defective NLRC4-dependent IL-1Ra production.
View Article and Find Full Text PDFJ Antimicrob Chemother
April 2014
Objectives: Micafungin inhibits 1,3-β-D-glucan synthase and interferes with fungal cell wall synthesis. Clinically, micafungin has been shown to be efficacious for the treatment of invasive fungal infections. However, little is known about the immunomodulatory activity of micafungin in these infections.
View Article and Find Full Text PDFRationale: Hypoxia regulates the inflammatory-antiinflammatory balance by the receptor for advanced glycation end products (RAGE), a versatile sensor of damage-associated molecular patterns. The multiligand nature of RAGE places this receptor in the midst of chronic inflammatory diseases.
Objectives: To characterize the impact of the hypoxia-RAGE pathway on pathogenic airway inflammation preventing effective pathogen clearance in cystic fibrosis (CF) and elucidate the potential role of this danger signal in pathogenesis and therapy of lung inflammation.
Endogenous tryptophan (Trp) metabolites have an important role in mammalian gut immune homeostasis, yet the potential contribution of Trp metabolites from resident microbiota has never been addressed experimentally. Here, we describe a metabolic pathway whereby Trp metabolites from the microbiota balance mucosal reactivity in mice. Switching from sugar to Trp as an energy source (e.
View Article and Find Full Text PDFThe ability to tolerate Candida albicans, a human commensal of the gastrointestinal tract and vagina, implicates that host defense mechanisms of resistance and tolerance cooperate to limit fungal burden and inflammation at the different body sites. We evaluated resistance and tolerance to the fungus in experimental and human vulvovaginal candidiasis (VVC) as well as in recurrent VVC (RVVC). Resistance and tolerance mechanisms were both activated in murine VVC, involving IL-22 and IL-10-producing regulatory T cells, respectively, with a major contribution by the enzyme indoleamine 2,3-dioxygenase 1 (IDO1).
View Article and Find Full Text PDFRationale: Mutations in the cystic fibrosis (CF) transmembrane conductance regulator affect the innate epithelial immune function of the lung, resulting in exaggerated and ineffective airway inflammation that fails to eradicate pathogenic fungi. The appreciation of whether such fungi are primarily responsible for or a consequence of ineffective airway inflammation is important for future therapeutics development.
Objectives: To characterize the impact of the tryptophan/kynurenine pathway on pathogenic airway inflammation preventing effective fungal clearance in CF.
Resistance and tolerance are two complementary host defense mechanisms that increase fitness in response to low-virulence fungi. Resistance is meant to reduce pathogen burden during infection through innate and adaptive immune mechanisms, whereas tolerance mitigates the substantial cost of resistance to host fitness through a multitude of anti-inflammatory mechanisms, including immunological tolerance. In experimental fungal infections, both defense mechanisms are activated through the delicate equilibrium between Th1/Th17 cells, which provide antifungal resistance, and regulatory T cells limiting the consequences of the ensuing inflammatory pathology.
View Article and Find Full Text PDFAspergillus fumigatus is a model fungal pathogen and a common cause of infection in individuals with the primary immunodeficiency chronic granulomatous disease (CGD). Although primarily considered a deficiency of innate immunity, CGD is also linked to dysfunctional T cell reactivity. Both CD4(+) and CD8(+) T cells mediate vaccine-induced protection from experimental aspergillosis, but the molecular mechanisms leading to the generation of protective immunity and whether these mechanisms are dysregulated in individuals with CGD have not been determined.
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