Foxp3 positive and negative cell comparison

ABSTRACT: Regulatory T cells have been shown to adopt a catabolic metabolic programme with increased capacity for fatty acid oxidation fuelled oxidative phosphorylation (OXPHOS). The role of Foxp3 in this metabolic shift is poorly understood. Here we show that Foxp3 was sufficient to induce a significant increase in the spare respiratory capacity of the cell, the extra OXPHOS capacity available to a cell to increased demands on energy in response to work. Foxp3-expressing cells were enhanced in their ability to utilise palmitate for respiration and in addition the activity of electron transport complexes I, II and IV were enhanced following Foxp3 expression. ATP was secreted by both T effector and regulatory T cells and was reduced by mitochondrial respiration inhibitors. Thus Foxp3 imparts a selective advantage in ATP generation capacity to the cell and may exploit this as a source of adenosine for functional immunomodulation. In order to explore possible mechanisms for these differences in metabolism we conducted a comparative quantitative proteomics study to compare the contribution of TGFβ and the transcription factor Foxp3 to the Treg proteome. We used quantitative mass spectrometry to examine differences between proteomes of nuclear and cytoplasmic Foxp3-containing T cells and Foxp3 positive iTreg and Foxp3 negative activated CD4 T cells in addition to human peripheral blood natural Treg. Gene set enrichment analysis of our proteomic datasets demonstrated that Foxp3 drives a significant up regulation of several members of the mitochondrial electron transport chain.

INSTRUMENT(S): LTQ Orbitrap

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): T Cell

SUBMITTER: Duncan Howie  

LAB HEAD: Dr Duncan Howie

PROVIDER: PXD001789 | Pride | 2017-02-15

REPOSITORIES: Pride