Maintenance of GVL on anti-OPN treatment. Lethally irradiated B6/SJL recipient mice were injected with C3H.SW CD8⁺ T cells plus C3H.SW TCD BM. These recipients were treated with anti-OPN Ab or control IgG at days 0, 3, 6, 10, and 14 after transplantation. (A) Splenic donor-derived CD8⁺ T cells were recovered from anti-OPN Ab or control IgG treated recipients at day 14 after transplantation, and the levels of inflammatory cytokine production were assessed by intracellular staining and flow cytometry. Gray shadow and solid line indicate the immunofluorescence intensity of cells as a control and the test of Abs, respectively. (B) Abilities of the recovered CD8⁺ T cells to lyse EL-4 cells were examined. Data of the percentages of specific lysis are mean plus or minus SEM of 6 mice per group. (C) The recipient mice were in vivo challenged with EL-4 cells at day 7 after transplantation. Survival and causes of death were monitored (n = 12 per group). Symbols are as follows: (▴), TCD BM alone; (▿), TCD BM plus EL-4 cells; (■), TCD BM plus CD8⁺ T cells plus EL-4 cells plus control IgG treatment; and (○), TCD BM plus CD8⁺ T cells plus EL-4 cells plus anti-OPN Ab treatment. These results were representative of 3 independent experiments. *P < .05.