Tregs accumulate in mLNs in α-GalCer-lipo–treated mice. Recipient mice received Foxp3^GFP+Luc+ cells with Ctrl-lipo (blue; n = 7) or α-GalCer-lipo (red; n = 7) and were euthanized 5 minutes after luciferase injection on day 10 after BMT. Organs were removed and images were acquired within 15 minutes after luciferase injection. (A) Representative images of ex vivo BLI. Far right box indicates region of interest (ROI) for each organ. BM cell (BMC; gray; n = 6) control without Tcon/Foxp3^GFP+Luc+ Treg transfer. (B) Mean ± standard deviation of total flux (photons per second [p/s]) obtained from each ROI. Data pooled from 2 independent experiments. (C) Images of immunofluorescent staining of mLN for CD4 (Alexa Fluor 594; red), Foxp3GFP (Alexa Fluor 488; green), and 4′,6-diamidino-2-phenylindole (DAPI; blue). Left shows low magnification (10×; white bar indicates 100 μm); right shows high magnification of inset region (40×; white bar indicates 20 μm). *P < .05, **P < .01, ***P < .001 between indicated 2 groups calculated by ordinary 1-way analysis of variance with Holm-Sidak correction.