Expression of GARP selectively identifies activated human FOXP3+ regulatory T cells

  title={Expression of GARP selectively identifies activated human FOXP3+ regulatory T cells},
  author={Rui Wang and Lina Kozhaya and Frances Mercer and Alka Khaitan and Hodaka Fujii and Derya Unutmaz},
  journal={Proceedings of the National Academy of Sciences},
  pages={13439 - 13444}
The molecules that define human regulatory T cells (Tregs) phenotypically and functionally remain to be fully characterized. We recently showed that activated human Tregs express mRNA for a transmembrane protein called glycoprotein A repetitions predominant (GARP, or LRRC32). Here, using a GARP-specific mAb, we demonstrate that expression of GARP on activated Tregs correlates with their suppressive capacity. However, GARP was not induced on T cells activated in the presence of TGFβ, which… 

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