Milieu-adjusted (physiological) oxygen concentration and immune reactivity

from: Kanada et al. 2013, Nature Immunology

Ambient air comprises about 20% oxygen, but oxygen levels in the different compartments of the human body are expected to be far below this. There is growing evidence that tissue oxygen levels are between 1-13%, depending on localization, vascularization and inflammatory state. It is known that various cellular mechanisms can be influenced by reduction or oxidation, and especially for immune cells, function can be modulated greatly. Therefore it is crucial to investigate immune cells under the expected physiological oxygen tension

The gut is the largest human surface which is in direct contact to a vast amount of various microorganisms, while the underlying mechanisms that define homeostasis, health and disease are still poorly understood. In the colonic mucosa oxygen is thought to be as low as 1%, and some studies underline this. It is reasonable to expect that this local environment influences the reactivity of the colon epithelial cells and immune cells present in this compartment, like for example T cells. So, we are investigating the reactivity of the human colon epithelial cell line CaCo-2 and human T- cells isolated from whole blood of healthy volunteers under 1% oxygen.