Pulmonary paracoccidioidomycosis in AhR deficient hosts is severe and associated with defective Treg and Th22 responses

• Published in: Scientific reports 2020-07, Vol.10 (1), p.11312-11312, Article 11312
• Main Authors: de Araújo, Eliseu Frank, Preite, Nycolas Willian, Veldhoen, Marc, Loures, Flávio Vieira, Calich, Vera Lúcia Garcia
• Format: Article
• Language: English
• Subjects: 631/250; 631/250/255; 631/250/255/1672; Adaptive immunity; Animals; Basic Helix-Loop-Helix Transcription Factors - genetics; Basic Helix-Loop-Helix Transcription Factors - physiology; Dioxygenase; Foxp3 protein; Helper cells; Humanities and Social Sciences; Immune response; Indoleamine-Pyrrole 2,3,-Dioxygenase - metabolism; Infections; Interleukin 22; Lung - immunology; Lung - pathology; Lung diseases; Lymphocytes T; Lymphoid cells; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; multidisciplinary; Myeloid cells; Paracoccidioidomycosis - immunology; Phenotypes; Receptors, Aryl Hydrocarbon - genetics; Receptors, Aryl Hydrocarbon - physiology; Science; Science (multidisciplinary); South American blastomycosis; Th17 Cells - immunology; Th17 Cells - pathology
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-68322-6

AhR is a ligand-activated transcription factor that plays an important role in the innate and adaptive immune responses. In infection models, it has been associated with host responses that promote or inhibit disease progression. In pulmonary paracoccidioidomycosis, a primary fungal infection endemic in Latin America, immune protection is mediated by Th1/Th17 cells and disease severity with predominant Th2/Th9/Treg responses. Because of its important role at epithelial barriers, we evaluate the role of AhR in the outcome of a pulmonary model of paracoccidioidomycosis . AhR −/− mice show increased fungal burdens, enhanced tissue pathology and mortality. During the infection, AhR −/− mice have more pulmonary myeloid cells with activated phenotype and reduced numbers expressing indoleamine 2,3 dioxygenase 1. AhR-deficient lungs have altered production of cytokines and reduced numbers of innate lymphoid cells (NK, ILC3 and NCR IL-22). The lungs of AhR −/− mice showed increased presence Th17 cells concomitant with reduced numbers of Th1, Th22 and Foxp3 + Treg cells. Furthermore, treatment of infected WT mice with an AhR-specific antagonist (CH223191) reproduced the main findings obtained in AhR −/− mice. Collectively our data demonstrate that in pulmonary paracoccidioidomycosis AhR controls fungal burden and excessive tissue inflammation and is a possible target for antifungal therapy.