Tim-3/gal-9 expression is up-regulated during acute GVHD. (A) B6 mice were lethally irradiated (11.0 Gy) and infused with 10⁷ MHC-mismatched BALB/c NTCD BM and 3 × 10⁶ BALB/c purified T cells. Recipient mice were killed on day 7, along with 3 naive BALB/c mice for control, and the spleens were examined by flow cytometry for Tim-3 expression. Cells were gated on CD4 or CD8 positive, H-2K^d positive events. (B) CFSE-labeled BALB/c purified T cells (10⁷) were transferred into lethally irradiated B6 recipients. Spleens were harvested and analyzed by flow cytometry for CFSE dilution and Tim-3 expression on days 3, 4, and 5. Data shown are representative of 4 mice per group per day. Cells were gated on CD4 or CD8 positive, H2K^d positive events. Numbers indicate percentage of Tim-3⁺ cells. (C) B6 mice were lethally irradiated and infused with 10⁷ BALB/c NTCD BM and 3 × 10⁶ BALB/c purified T cells and killed on day 7. Cryosections from the spleen of BM only recipients (top) and T-cell recipients (bottom) were stained for CD45 in FITC (shown in green) and gal-9 (shown in red). Original magnification ×20. Pictures are representative of 2 experiments, with 3 to 4 mice/group.