Batf3-dependent regulation of the antifungal inflammatory response after pulmonary Aspergillus fumigatus challenge

Abstract

Abstract Aspergillus fumigatus is a ubiquitous fungus that causes invasive aspergillosis in immunocompromised individuals. The innate immune system is critical in the maintenance of host resistance against A. fumigatus. While it is well established that monocyte-derived dendritic cells (moDC) are critical in maintaining host resistance against A. fumigatus, the role of other dendritic cells populations has not been thoroughly explored. Here we demonstrate that Batf3-dependent cells, likely classical type 1 dendritic cells (cDC1s), are critical in preventing invasive aspergillosis. Surprisingly, Batf3(−/−) mice display an elevated inflammatory response against A. fumigatus, particularly IL-17A/F. We show that elevated concentrations of IL-17A/F in the lungs of Batf3(−/−) mice following A. fumigatus infection perpetuates the secretion of various inflammatory lung cytokines in vivo. Neutralization of both IL-17A and IL-17F in Batf3(−/−) mice prevent excessive cytokine secretion and mortality due to A. fumigatus challenge of Batf3(−/−) mice. Following A. fumigatus challenge regulatory T cells are known to limit inflammation. Our preliminary antibody-mediated depletion studies demonstrate that CD4+ CD25+ T cells may be involved in preventing excessive IL-17A/F release in immunocompetent mice. In this study we have identified a critical role for Batf3-dependent cells in limiting A. fumigatus induced inflammatory and mortality due to IL-17 driven lung pathology. Supported by NIH: [R01 AI139133-01A1]