FIGURE 3.

Illustrating the range of variables that could explain differences between published data on Treg cell metabolism and function. Different teams work on Treg cells from different species, different tissue systems and disease settings. This has implications for the type of microenvironment that the Treg cells will have been adapted for. Moreover, any subsequent in vitro or ex vivo experiments are often carried out in different culture conditions involving different types of media, concomitant pharmacological agents as well as atmospheric oxygen concentrations. Furthermore, the competition for metabolites is different depending on the presence of competing effector cells as well as the constitutive Treg cell metabolic program.