Subcellular localization of FOXP3 in human regulatory and nonregulatory T cells.

The transcriptional regulator FOXP3 is an important determinant of regulatory T (Treg) cell development and function and is frequently used to quantitate Treg cells. However, FOXP3 is also expressed in recently activated conventional human T cells. Here, we investigated the FOXP3 expression patterns in Treg and activated T cells at a cellular level.