Fig. 1.

The ΔE mutation in the leucine-zipper domain of Foxp3 prevents generation of functional regulatory T cells. (A) Each Foxp3 and Foxp3 ΔE cDNA was cloned into MSCV 2.2 retroviral vectors containing the marker GFP. (B) CD4+CD25− T cells from C57BL/6 mice were transduced with retroviruses, and GFP-positive cells were then sorted. (C) GFP-positive cells were analyzed by real-time PCR for Foxp3 expression. (D) The effect of transduced CD4+ T cells on the progression of IBD was monitored by mean body weight. Closed circles, null vector; closed squares, wild-type Foxp3; closed triangles, Foxp3ΔE.