In-depth proteomic analysis of regulatory T cells (Tregs)
Regulatory T cells (Treg) represent a minor sub-population of T lymphocytes which is crucial for the maintenance of immune homeostasis. In collaboration with A. Saoudi (CPTP, Toulouse), we used large-scale quantitative mass spectrometry to define a specific proteomic “signature” of Treg.
Treg and conventional T lymphocyte (Tconv) sub-populations were sorted by flow cytometry and subjected to global proteomic analysis by single-run nanoLC-MS/MS on a fast-sequencing Q-Exactive mass spectrometer. Besides “historical” proteins that characterize Treg, our study identified numerous new proteins that are up- or down-regulated in Treg versus Tconv.
We focused on Themis1, a protein particularly under-represented in Treg, and recently described as being involved in the pathogenesis of immune diseases. Using a transgenic mouse model over-expressing Themis1, we provided in vivo and in vitro evidence of its importance for Treg suppressive functions, in an animal model of inflammatory bowel disease and in co-culture assays.
Duguet F, Locard-Paulet M et al (2017) Proteomic analysis of regulatory T cells reveals the importance of Themis1 in the control of their suppressive function. Mol Cell Proteomics. 2017