Faecalibacterium duncaniae as a novel next generation probiotic against influenza

Abstract

The gut-lung axis is critical during viral respiratory infections such as influenza. Gut dysbiosis during infection translates into a massive drop of microbially produced short-chain fatty acids (SCFAs). Among them, butyrate is important during influenza suggesting that microbiome-based therapeutics targeting butyrate might hold promises. The butyrate-producing bacterium <i>Faecalibacterium duncaniae</i> (formerly referred to as <i>F. prausnitzii</i>) is an emerging probiotic with several health-promoting characteristics. To investigate the potential effects of <i>F. duncaniae</i> on influenza outcomes, mice were gavaged with live <i>F. duncaniae</i> (A2-165 or I-4574 strains) five days before infection. Supplementation of <i>F. duncaniae</i> was associated with less severe disease, a lower pulmonary viral load, and lower levels of lung inflammation. <i>F. duncaniae</i> supplementation impacted on gut dysbiosis induced by infection, as assessed by 16S rRNA sequencing. Interestingly, <i>F. duncaniae</i> administration was associated with a recovery in levels of SCFAs (including butyrate) in infected animals. The live form of <i>F. duncaniae was</i> more potent that the pasteurized form in improving influenza outcomes. Lastly, <i>F. duncaniae</i> partially protected against secondary (systemic) bacterial infection. We conclude that <i>F. duncaniae</i> might serve as a novel next generation probiotic against acute viral respiratory diseases.