%0 Journal Article
%T Helios Expression Is a Marker of T Cell Activation and Proliferation
%A Tatiana Akimova
%A Ulf H. Beier
%A Liqing Wang
%A Matthew H. Levine
%A Wayne W. Hancock
%J PLOS ONE
%D 2011
%I Public Library of Science (PLoS)
%R 10.1371/journal.pone.0024226
%X Foxp3+ T-regulatory cells (Tregs) normally serve to attenuate immune responses and are key to maintenance of immune homeostasis. Over the past decade, Treg cells have become a major focus of research for many groups, and various functional subsets have been characterized. Recently, the Ikaros family member, Helios, was reported as a marker to discriminate naturally occurring, thymic-derived Tregs from those peripherally induced from na£żve CD4+ T cells. We investigated Helios expression in murine and human T cells under resting or activating conditions, using well-characterized molecules of na£żve/effector/memory phenotypes, as well as a set of Treg-associated markers. We found that Helios-negative T cells are enriched for na£żve T cell phenotypes and vice versa. Moreover, Helios can be induced during T cell activation and proliferation, but regresses in the same cells under resting conditions. We demonstrated comparable findings using human and murine CD4+Foxp3+ Tregs, as well as in CD4+ and CD8+ T cells. Since Helios expression is associated with T cell activation and cellular division, regardless of the cell subset involved, it does not appear suitable as a marker to distinguish natural and induced Treg cells.
%U http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0024226