Lung microbiota and the gut-lung axis

Abstract

Introduction: In the light of the most recent knowledge, it is important to emphasize the potential role played by the gut microbiota, through the gut-lung axis, with the lung microbiota.

Objective: Update the criteria about the lung microbiota in healthy subjects and its relationship with the gut-lung axis.

Methods: Publications in Spanish and English were reviewed in PubMed, Google Scholar, ScIELO, from January 2010 to May 2020; the following terms were used: lung microbiota, lower respiratory tract microbiota, gut-lung axis, lung microbiota and immunity and next- generation probiotics.

Analysis and integration of information: Arguments related to the presence of commensal microbiota resident in the lung formed by bacteria, fungi and viruses as members of the microbial community are presented. Role of the gut-lung axis and its participation in immune modulation. Features of the lung microbiota, its biomass, diversity, and component phylums are described. Researches in animals are summarized. The value of the new 16S gene sequencing technology of rRNA for study and identification is highlighted.

Final considerations: The lung was considered a sterile organ. Here the presence of resident commensal microbiota of great diversity in the lung is documented; the mechanisms of the gut-lung axis and its role in the modulation of lung immunity and diagnostic value in diseases of the lower respiratory tract are stated. The future use of next-generation probiotics as modulators of the lung microbiota is emphasized.