Figure 6.

Survival curve and leukemic-tumor-burden in dose-reduction experiments with CD8-depleted splenocytes. Experiments were the same as in Fig. 5 but the donor splenocyte was CD8-depleted. Like the bulk splenocyte experiment (Fig. 5), the starting dose was 5 × 10⁷ WT-SP or KO-SP (H-2^b). Then, the dose of CD8-depleted splenocytes was reduced to 5 × 10⁶, and 5 × 10⁵, gradually. Open squares, filled squares, and filled triangles indicate transplantations without splenocytes, with WT-SP, and with KO-SP, respectively. Right panels indicate the average of signal intensity of luminescence in survivors at indicated days after transplantation, which correlates with leukemic-tumor-burden. Empirically determined positive-negative threshold indicated in broken line was 10⁶ relative signal intensity per mouse.