The revolution in microbiota research over the past decade has provided invaluable knowledge about the function of the microbial species that inhabit the human body. It has become widely accepted that these microorganisms, collectively called ‘the microbiota’, engage in networks of interactions with each other and with the host that aim to benefit both the microbial members and the mammalian members of this unique ecosystem. The lungs, previously thought to be sterile, are now known to harbor a unique microbiota and, additionally, to be influenced by microbial signals from distal body sites, such as the intestine. Here we review the role of the lung and gut microbiotas in respiratory health and disease and highlight the main pathways of communication that underlie the gut–lung axis.
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T.P.W. is supported by a Postdoc Mobility Fellowship from the Swiss National Science Foundation. B.J.M. is an NHMRC Senior Research Fellow and a VESKI Innovation Fellow.
The authors declare no competing interests.
Peer review information: Jamie D.K. Wilson was the primary editor on this article and managed its editorial process and peer review in collaboration with the rest of the editorial team.
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