FTY720 reduces the number of circulating allo-T-bodies in the recipient mice and increases T-body number in the spleen. (A) Comparative in vivo BLI of Renca-Her2/neu-bearing mice (n = 6) irradiated with 400 rads, and treated with either 30 × 10⁶ syngeneic (Balb-N29) or allogeneic (Black-N29) T-bodies. BLI was performed as in Figure 4A. (B) Whole body BLI signal intensities from sequential imaging depicted above, and measured every 3-4 days after T cell transfer from the same groups shown in panel A. Each line represents 1 animal. (C) A region of interest was defined around the spleens of mice from panel A. Shown are absolute photon counts from mice treated with allogeneic T-bodies either with or without FTY720. Means and SEM are shown. (D) Mononuclear cells were isolated 4 days after adoptive transfer from the blood of tumor-bearing mice treated with allogeneic T-bodies either with or without FTY720, and the number of T cells in the blood was quantified by staining for CD3. Means and SEM are shown. (E-F) Splenocytes of tumor-bearing mice treated with allogeneic T-bodies either with or without FTY720, were stained with anti-H2K^b 4 (E) or 7 (F) days after adoptive transfer to identify the allogeneic T-bodies. Means and SEM are shown. Each line represents 1 animal.