Impact of a 3-Months Vegetarian Diet on the Gut Microbiota and Immune Repertoire

Front Immunol. 2018 Apr 27;9:908. doi: 10.3389/fimmu.2018.00908. eCollection 2018.

Abstract

The dietary pattern can influence the immune system directly, but may also modulate it indirectly by regulating the gut microbiota. Here, we investigated the effect of a 3-months lacto-ovo-vegetarian diet on the diversity of gut microbiota and the immune system in healthy omnivorous volunteers, using high-throughput sequencing technologies. The short-term vegetarian diet did not have any major effect on the diversity of the immune system and the overall composition of the metagenome. The prevalence of bacterial genera/species with known beneficial effects on the intestine, including butyrate-producers and probiotic species and the balance of autoimmune-related variable genes/families were, however, altered in the short-term vegetarians. A number of bacterial species that are associated with the expression level of IgA, a key immunoglobulin class that protects the gastrointestinal mucosal system, were also identified. Furthermore, a lower diversity of T-cell repertoire and expression level of IgE, as well as a reduced abundance of inflammation-related genes in the gut microbiota were potentially associated with a control group with long-term vegetarians. Thus, the composition and duration of the diet may have an impact on the balance of pro-/anti-inflammatory factors in the gut microbiota and immune system.

Keywords: B-cell; T-cell; gut microbiota; immune repertoire; immunoglobulin; vegetarian.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Bacteria / classification
  • Bacteria / metabolism*
  • Butyrates / metabolism
  • Diet, Vegetarian*
  • Female
  • Gastrointestinal Microbiome / genetics*
  • Gastrointestinal Microbiome / immunology*
  • High-Throughput Nucleotide Sequencing
  • Humans
  • Immunity, Mucosal
  • Immunoglobulin A
  • Inflammation
  • Male
  • Metagenome*
  • Middle Aged
  • Probiotics
  • Time Factors
  • Vegetarians

Substances

  • Butyrates
  • Immunoglobulin A