{
  "id": 7877803,
  "title": "Gut archaea drive human MAIT cell responses",
  "url": "https://urgent.news/2026/09/16/gut-archaea-drive-human-mait-cell-responses",
  "topic": "science",
  "section": "Science",
  "published": "2026-09-16T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.09.11.750638v1?rss=1"
  },
  "original_language": "en",
  "account": "Archaea, a previously understudied third domain of life, are found within the human gut microbiome. However, their impact on the immune system remains unclear. Mucosal-associated invariant T (MAIT) cells play a crucial role in combating germs and maintaining the integrity of the body's protective barriers. These cells identify microbial metabolites through their T cell receptor, contributing significantly to the body's defence mechanisms. The primary source of MAIT cell antigen 5-OP-RU within the human gut is yet to be identified. Researchers analysed microbiomes from individuals in the UK, Zambia, Kenya, and Uganda. They discovered a strong connection between the presence of archaeal riboflavin biosynthesis and the frequency and activation of MAIT cells in the bloodstream. Additionally, the levels of 5-OP-RU in stool samples were found to correlate with the abundance of archaea. Cultures of methanogenic archaea, including the human commensal Methanobrevibacter smithii, generated 5-OP-RU, which strongly activated MAIT cells without causing any inflammation. The study reveals that archaea play a pivotal role in shaping human immunity, with important implications for understanding how the microbiome regulates health.",
  "summary": "Archaea, the third domain of life, are a gut microbiome constituent, but their role in shaping immunity is poorly understood. Mucosal-associated invariant T (MAIT) cells sense microbial metabolites through their T cell receptor and contribute to antimicrobial defence and barrier homeostasis. Key sources of the major MAIT cell antigen 5-OP-RU within the human gut microbiome are unknown. Analysing…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}