The gut microbiota is involved in the lung’s defense against viral respiratory infections

The microbiota plays a key role in the development, education and function of the immune system, both locally and systemically. While the airway microbiota locally regulates immune function, the gut microbiota can also influence respiratory immunity, via the gut-lung axis.¹ Alteration of the lung and gut microbiota has been observed in many respiratory diseases, however whether the dysbiosis at these sites is a cause or a consequence of disease remains to be determined.² Alteration of gut microbiota composition, through either diet, antibiotic use, aging, or disease, is associated with altered immune responses and homeostasis in the airways,³ highlighting that the gut microbiota can influence disease development throughout the body, including the risk of respiratory infections (Fig 6).⁴

About this article

Created 23 November 2021

Updated 15 July 2024

In comparison to the gut microbiota, studies on the lung microbiota are still in their infancy.⁵ The lung was originally thought to be sterile but recently, researchers have discovered that the lung harbours its own microbiota, with a composition distinct from the gut microbiota.⁶

Any factors inducing microbiota dysbiosis can alter the beneficial gut-lung cross-talk, increasing susceptibility to respiratory infections.¹⁰

Studies have shown that gut microbiota may be involved in providing protection against viral respiratory infections (such as influenza and respiratory syncytial virus),² via numerous mechanisms. For example, gut microbial metabolites such as SCFAs (obtained from dietary fiber fermentation by commensal bacteria) and desaminotyrosine (a degradation product of plant flavonoids produced by human gut bacteria)⁷ influence the lung production of Type I interferon (IFNs) which elicit anti-viral protection. ^8,9Along with microbial metabolites, microbial components (such as LPS) help arm the lungs against viral respiratory infections (Fig 6). The gut microbiota also plays a role in viral (influenza) clearance by stimulating CD8+ T-cell effector function.¹⁰

FIGURE 6: The role of the gut microbiota in viral respiratory infections.

Adapted from Sencio V et al, 2020¹⁰

Any factors inducing gut microbiota dysbiosis (aging, antibiotics, diseases such as obesity, diabetes…) can also alter the normally beneficial gut-lung cross-talk, increasing susceptibility to respiratory infections.¹⁰

Sources

^{1 Taylor SL, Wesselingh S, Rogers GB. Host-microbiome interactions in acute and chronic respiratory infections. Cell Microbiol. 2016 May;18(5):652-62.}

^{2 Dumas A, Bernard L, Poquet Y, et al. The role of the lung microbiota and the gut-lung axis in respiratory infectious diseases. Cell Microbiol. 2018 Dec;20(12):e12966.}

^{3 Dang AT, Marsland BJ. Microbes, metabolites, and the gut-lung axis. Mucosal Immunol. 2019 Jul;12(4):843-850.}

^{4 Thibeault C, Suttorp N, Opitz B. The microbiota in pneumonia: From protection to predisposition. Sci Transl Med. 2021 Jan 13;13(576):eaba0501.}

^{5 Huffnagle GB, Dickson RP, Lukacs NW. The respiratory tract microbiome and lung inflammation: a two-way street. Mucosal Immunol. 2017 Mar;10(2):299-306.}

^{6 Man WH, de Steenhuijsen Piters WA, Bogaert D. The microbiota of the respiratory tract: gatekeeper to respiratory health. Nat Rev Microbiol. 2017 May;15(5):259-270.}

^{7 Schoefer L, Mohan R, Schwiertz A, et al. Anaerobic degradation of flavonoids by Clostridium orbiscindens. Appl Environ Microbiol. 2003 Oct;69(10):5849-54.}

^{8 Antunes KH, Fachi JL, de Paula R, et al. Microbiota-derived acetate protects against respiratory syncytial virus infection through a GPR43-type 1 interferon response. Nat Commun. 2019 Jul 22;10(1):3273.}

^{9 Steed AL, Christophi GP, Kaiko GE, et al. The microbial metabolite desaminotyrosine protects from influenza through type I interferon. Science. 2017 Aug 4;357(6350):498-502.}

^{10 Sencio V, Machado MG, Trottein F. The lung-gut axis during viral respiratory infections: the impact of gut dysbiosis on secondary disease outcomes. Mucosal Immunol. 2021 Mar;14(2):296-304.}

Tags

Gut microbiota Dysbiosis Immunity Virus Viral Lungs Immune response Microbiome Flora

Dampening gastrointestinal inflammation through nutrition

Gut-lung axis in viral respiratory infections

Focus

Microbiota, a diplomatic immunity?

Introduction

Understanding the complex interplay between the microbiota and immunity is only just beginning

Intestinal Immunity

The infant's gut at the heart of immunity Factors influencing microbiota development and maturation of the immune system early in life The impact of western diet on the mucus layer Dampening gastrointestinal inflammation through nutrition

Gut microbiota influences respiratory immunity

The gut microbiota is involved in the lung’s defense against viral respiratory infections Gut-lung axis in viral respiratory infections The hygiene hypothesis and the COVID-19 pandemic Targeting the gut microbiota to optimize vaccine efficacy?

Role of the microbiota in skin immunity and atopic dermatitis

Expert interview: Pr. Brigitte Dréno

Conclusion

What to take away? Intestinal Immunity What to take away? Respiratory immunity What to take away? Skin immunity