The human archaeome: methodological pitfalls and knowledge gaps

Area of Science:

• Microbiology
• Human Microbiome Research
• Archaea Biology

Background:

• Archaea, a distinct domain of life, are known inhabitants of the human gut and mouth.
• Knowledge of the human archaeome is limited due to methodological issues, creating significant knowledge gaps.
• Previous studies suggest site-specific archaeal distribution in the human body.

Purpose of the Study:

• To investigate the diversity, quantity, and distribution of archaea in various human body sites.
• To compare archaeal signatures using archaea-specific protocols versus universal microbiome approaches.
• To explore the potential roles of human-associated archaea in health and disease.

Main Methods:

• Utilized archaea-specific protocols to analyze archaeal communities in different human tissues.
• Compared findings with results from universal microbiome approaches.
• Investigated archaeal biogeography across various body sites, including skin, gastrointestinal tract, nose, and lungs.

Main Results:

• Archaea exhibit site-specific biogeography: thaumarchaeal skin landscape, (methano)euryarchaeal GIT landscape, mixed skin/GIT in the nose, and a lung landscape with unknown clades.
• Archaea-specific protocols reveal high archaeal diversity and quantity, with bacteria-to-archaea ratios up to 1:1 in appendix and nose samples.
• Human-associated archaea interact with the bacteriome and host cells, but their health implications are sparsely described.

Conclusions:

• Archaea are significant components of the human microbiome with distinct site-specific distributions.
• Archaea-specific methods are crucial for accurately assessing the human archaeome.
• The role of archaea in human health and disease, including the existence of archaeal pathogens, requires further investigation.