Immunology of Sepsis.

Sepsis-related immune dysregulation occurs in three overlapping phases, including pathogen recognition, inflammation, and immune paralysis. There are many immune cells that underlie these three phases, with the most well-studied being epithelial cells, neutrophils, monocytes, macrophages, and T cells. These cells regulate multiple downstream mediators, such as cytokines and chemokines, that can be measured and used as immunologic biomarkers. Past failures in sepsis immune-modulating treatment trials have likely resulted from the inclusion of patients meeting sepsis clinical criteria but who do not sufficiently express the immunologic target under investigation. More precise approaches to trial designs may uncover effective immune-modulating therapies.