The role of HIF in immunity.

Oxygen is an essential nutrient for eukaryotic life and in complex organisms a finely tuned system, based on Hypoxia Inducible Factor (HIF), has evolved to control the cellular, local and organism-wide responses to its availability. Cells of the immune system must function in a variety of local environments and it is now clear that oxygen availability is an important signal for the cells involved in immune defence. This review summarises the mechanisms by which activation of the HIF pathway influences, and is influenced by, both immune activation state and oxygen tension. It is likely that understanding how oxygen tension modulates immune function will provide insights into disease pathogenesis, and may offer new opportunities for treatment.