Title: Archaea and Their Potential Role in Human Disease | Infection and Immunity
Headings: Archaea and Their Potential Role in Human Disease
Archaea and Their Potential Role in Human Disease
POTENTIAL PATHOGENICITY OF ARCHAEA
POTENTIAL ASSOCIATIONS OF ARCHAEA WITH HUMAN DISEASE
CONCLUSION AND FUTURE STUDIES
ACKNOWLEDGMENTS
REFERENCES
KEYWORDS

Content: In general, pathogens are distinguished from commensals by their reliance on a strategy for survival and replication in or transmission from a host that regularly leads to cellular, tissue, or organismal damage. Strategies can vary enormously, but they often define a signature for a family of pathogens. These strategies involve gaining access to the host in sufficient numbers, adhering to and colonizing a niche, evading host defenses, and multiplying in the host ( 50 ). If some archaea behave as pathogens they probably follow this basic scheme, but they may use fundamentally different mechanisms at some or all of these steps. (i) Access and colonization. The ubiquity of archaea in nature provides them ample opportunity for access to and colonization of susceptible hosts. In fact, we know of multiple niches for archaea in the human host. Methanogens, for example, have been identified among the human colonic ( 36 ), subgingival ( 1, 6, 29 ), and vaginal flora ( 2 ). Given their requirement for strictly anaerobic microenvironments, methanogens are likely to exist in human anatomic sites where well-characterized anaerobic bacteria flourish, possibly as coinhabitants. Specific surface interactions between host cells and archaea have not been characterized, nor have specific mechanisms involved in cell or tissue tropism.