The effect of pulmonary infection with Aspergillus fumigatus on lung and gut microbiota in Dark Agouti and Albino Oxford rats

Abstract

Objective: The little data of the effect of pulmonary fungal infection on lung and gut microbiota exist, thus aim of our study was to examine the effect of Aspergillus fumigatus infection on bacterial homestasis in these organs in Dark Agouti (DA) and Albino Oxford (AO) rats known to develop different immune responce to the fungus. Methods: 16S rRNA amplicon sequencing of the V3-V4 hypervariable region. Enzyme-linked immunosorbent assay for cytokine content (IL-10, IL-6, TNF, IL-1beta, IL-17 i IFN-gamma) in lung and gut homogenats, and plasma (IL- 6, IL-17, TNF). Myeloperoxidase, catalase, glutathione S-transferase and content of reduced glutathione in lung homogenates. Results: No initial differences in lung bacterial microbiota between healthy DA and AO rats exists, but A. fumigatus infection resulted in increase in alpha diversity (without effect on bacterial composition) in both strains. Changes in relative abundance at genus and species level were expressed differently (increased in DA, decreased in AO). Dysbiosis in lung coincided with increase of IFN-gamma, IL-17 and MPO in both strains, and increase oxidative stress solely in DA. Gut inflammation was noted in both strains, while bacterial dysbiosis only in DA. Conclusions: Pulmonary fungal infection resulted in bacterial dysbiosis in lung (in both rat strains), and gut (solely in DA). Noted lung and gut inflammation in these two rat strains, coexisted with different effects on bacterial homeostasis, which could be due to different genetic background or bacterial composition prior infection.