Fig. 3.

Bortezomib administration reduces donor-derived T cell expansion after BMT. B6 (H-2^b) recipients of 15 million BALB/c (H-2^d) T cell-depleted bone marrow and 15 million CFSE-labeled purified T cells were treated with bortezomib or vehicle control (PBS) daily on day 0 and day +2 post-BMT. Each treatment group consists of three mice per group. Representative data from one of two independent experiments are presented. (A) Significant reductions (Student's t test; P < 0.05) in donor-derived CD4⁺ and CD8⁺ splenocytes were observed on days +3 and +4 post-BMT of bortezomib-treated mice. (B) Significant increases in annexin V binding on proliferating (CFSE^lo) but not on nonalloreactive (CFSE^hi) CD4⁺ and CD8⁺ T cells in spleens from bortezomib-treated mice on day +3 post-BMT. (C) B6 (H-2^b) recipients of 15 million BALB/c (H-2^d) bone marrow and 20 million spleen cells were treated with bortezomib or vehicle control (PBS) daily from day 0 through day +2 post-BMT. Mice were bled on days +7 and +30 after BMT. Serum was analyzed for TNF-α as described in Materials and Methods. Significant reductions (Student's t test; P < 0.05) in serum TNF-α were observed at both time points in bortezomib-treated mice. Representative data from one of two independent experiments are presented.