title: Expression of Helios in peripherally induced Foxp3+ regulatory T cells.
abstract: The transcription factor Helios has been reported to be a marker of regulatory T cells (Treg) of thymic origin, distinguishing them from Treg induced in the periphery (iTreg). In this study, we demonstrate Helios expression in Foxp3(+) iTreg, both in vitro and in vivo. Following i.v. peptide injection, in vivo Helios expression in adoptively transferred TCR transgenic T cells was more rapid than Foxp3 induction but less stable at later time points without a second injection of peptide. Our in vitro data suggest that APC influence Helios expression in a manner distinct from stimuli required for Foxp3 induction. Thus, Helios expression in iTreg may reflect the context of stimulation during Foxp3 induction. In summary, the robust Helios expression we observe in iTreg precludes its use as a marker of thymic Treg.
authors.affiliation: Department of Immunology, Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.
authors.forename: Rachel A
authors.initials: RA
authors.lastname: Gottschalk
authors.forename: Emily
authors.initials: E
authors.lastname: Corse
authors.forename: James P
authors.initials: JP
authors.lastname: Allison
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells; D051858:Forkhead Transcription Factors; D051740:Ikaros Transcription Factor / Q000096:biosynthesis*; D051379:Mice; D008822:Mice, Transgenic; D010455:Peptides / Q000008:administration & dosage; D050378:T-Lymphocytes, Regulatory / Q000378:metabolism; D014018:Tissue Distribution
chemical_list: D051858:Forkhead Transcription Factors; C498833:Foxp3 protein, mouse; C111431:IKZF2 protein, human; D010455:Peptides; D051740:Ikaros Transcription Factor