Although immune responses are generated by a complex, hierarchical arrangement of immune system organs, tissues, and components, the unit of the cell has a particularly large effect on disease progression and host survival. These cell-level defense mechanisms, known as cell-autonomous immunity, are among the most important determinants of human survival, and are millions to billions of years old, inherited from our prokaryotic and single-celled ancestors. The authors of a new paper published in the September 2020 issue of The Quarterly Review of Biology argue that understanding how cell-autonomous immunity has evolved in primates is crucial to understanding human evolution, not only because infectious agents thought to have affected human genomic evolution are excellent manipulators of cell-autonomous immunity, but because these defenses are found in every cell in every body system. In "Cell-Autonomous Immunity and the Pathogen-Mediated Evolution of Humans: Or How Our Prokaryotic and Single-Celled Origins Affect the Human Evolutionary Story," Jessica F. Brinkworth, PhD, and Alexander S. Alvarado, PhD, both from the Department of Anthropology and Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, discuss how the ubiquity of cell-autonomous immunity highlights a biological reality not commonly addressed in human evolutionary studies--pathogens can mediate the evolution of all body cells, and therefore, all human body systems.Login Or Register To Read Full Story