Role of the gut microbiota in defining human health

Abstract

The human superorganism is a conglomerate of mammalian and microbial cells, with the latter estimated to outnumber the former by ten to one and the microbial genetic repertoire (microbiome) to be approximately 100-times greater than that of the human host. Given the ability of the immune response to rapidly counter infectious agents, it is striking that such a large density of microbes can exist in a state of synergy within the human host. This is particularly true of the distal gastrointestinal (GI) tract, which houses up to 1000 distinct bacterial species and an estimated excess of 1 × 10¹⁴ microorganisms. An ever-increasing body of evidence implicates the GI microbiota in defining states of health and disease. Here, we review the literature in adult and pediatric GI microbiome studies, the emerging links between microbial community structure, function, infection and disease, and the approaches to manipulate this crucial ecosystem to improve host health.

Keywords::

• gastrointestinal tract
• inflammation
• microneme
• probiotics

Financial & competing interests disclosure

Susan V Lynch is supported by NIH awards AI075410, HL098964, T004732 and DK083990, and by the Rainin Foundation. Michael D Cabana is supported by NIH awards A112997, AT004732 and HL080074. NA Slusher is supported by a MBRS RISE award 5R25GM-059298. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.