Figure 6.

Bcl-x_L does not interfere with the effects of anti-CD28 treatment. (A) Thy1.2⁺ cells from B6 WT or Bcl-x_L transgenic donors were transplanted into irradiated BALB/c recipients. Groups of three mice each were treated with control or anti-CD28 mAb. At 84 hours after the transplant, pooled splenocytes were stained for expression of CD4, CD8, and H-2K^d. The absolute numbers of CD4⁺ and CD8⁺ donor T cells in the recipient spleen were calculated from the total number of splenocytes multiplied by the percentage of CD4⁺/H-2K^d– and CD8⁺/H-2K^d– cells in the total spleen population. (B) Purified CD4⁺ T cells from WT or Bcl-x_L transgenic B6 donors were injected into irradiated (700 cGy) bm12 mice. Recipients were given a single injection of hamster IgG or anti-CD28 mAb at 100 ∝g/mouse on the day of transplantation. Irradiated bm12 mice that received no cells were used as controls without GVHD. Five mice were used in each group.