Expanded CD25+Foxp3+Treg after DR3 activation prevent acute GVHD after allogeneic transplantation. CD4+CD25+ Treg (1 × 105-5 × 105/animal) from WT B6 mice with or without αDR3 treatment were transplanted together with T cells from B6-gfp/luc mice (1 × 106/animal) and TCD-BM from WT B6 mice into lethally irradiated Balb/c mice. (A) Donor T-cell proliferation in vivo was measured by BLI. Representative BLI image of GVHD control (left), Iso-Treg group (middle), and DR3-Treg group (right) on day 7 are shown. The summary of BLI on day 7 (ii) and day 10 (iii) are shown (n = 5; *P < .05; **P < .01; ***P < .001; ****P < .0001). (B) Representative immunohistochemistry images of liver (i) and ileum (ii) samples from transplanted mice on day 7 are shown (n = 3, green, donor T cells (GFP); blue, DAPI; scale bar, 200 μm). The frequencies of infiltrating donor GFP+ T cells into the tissue were calculated (iii-iv; n = 3; **P < .01; ***P < .001; ****P < .0001). (C) Serum inflammatory cytokine/chemokine levels (interferon γ, TNFα, CCL2, CXCL1, CXCL9, CXCL10) from transplanted mice are shown (n = 4 in each group; *P < .05; **P < .01). D-E. GVHD score and survival were assessed (n = 10 in each group; *P < .05).
