MSCs promote de novo generation and negative selection of T cells. Approximately 2.5×106 TCD-BM from EGFP-transgenic C57BL/6J donor alone (non-GVHD) or these plus 1 × 106 splenocytes from WT C57BL/6J donor were transplanted into BALB/c mice. Recipients treated with WT MSCs (MSC-GVHD) or normal saline (non–MSC-GVHD) on day 7 after HCT. (A) Schematic diagram depicting generation of the EGFP-BM GVHD murine model. (B) Representative fluorescence-activated cell sorting (FACS) plots (left) and quantification (right) of GFP+ T cells in CD3+ T cells of the blood, spleen, and lymph node of recipients on day 20 and day 40 after transplantation (n = 6 mice for each group). (C) Representative FACS plots (left) and quantification (right) of GFP+Vβ5+ T cells in CD3+ T cells of the blood, spleen, and lymph node of recipients on day 20 and day 40 after transplantation (n = 6 mice for each group). ∗P ＜ .05; ∗∗P ＜ .01; ∗∗∗P ＜ .001.
