Administration of anti–IL-7Rα antibody results in decreased proliferation of donor-derived T cells. A total of 1 × 10⁶ TCD BM and 4 × 10⁶ CFSE-labeled LN cells from allogeneic BALB/c donors were transplanted into lethally irradiated B6 recipients. At day 10, the frequency of proliferating CFSE-labeled allogeneic donor-derived (H2k^d-positive) CD4 and CD8 T cells in LN (to the left of the indicated bar) of the anti–IL-7Rα antibody-treated allogeneic BMT and LN recipients was less than that of the PBS-treated recipients.