GVL activity is partially preserved in CD18−/− T cells. Lethally irradiated BALB/c mice underwent BMT with 5 × 106 TCD BM cells alone or plus 2 × 106 naive T cells from WT or CD18−/− B6 donors. Recipients were given 2 × 103 A20 tumor cells with luciferase transgene as a separate intravenous injection at the same time of transplantation. Recipient survival (A) and body weight changes (B) are shown. Numbers of recipients given transplants of BM alone or plus WT or CD18−/− T cells were 7, 11, and 12, respectively, and data are pooled from 2 replicate experiments. (C) Recipients were tracked for in vivo luminescence 10 minutes after intraperitoneal injection of firefly luciferin; data represent 1 of 2 replicate experiments. (D) BMT was set as in panels A and B, and BALB/c recipients of WT or CD18−/− T cells were killed 2 weeks after transplantation. Splenocytes of each recipient were assayed directly for cytotoxicity without in vitro restimulation. The activity of cytolytic effectors was measured in a 4- to 5-hours cytotoxic assay against A20 or Yac-1 at an E/T ratio of 100:1. The data represent the means (± 1 SD) of percentage of specific killing from 3 to 4 replicate mice each group, and the percentage of killing is normalized based on the number of total T cells in the spleen. The assay was run in triplicate with less than 5% SE, and data represent 1 of 2 replicate experiments. (E) Splenocytes from WT or CD18−/− B6 donors were stimulated with IL-2 for 3 days and used as effector cells to kill Yac-1 (NK-sensitive targets) or A20 cells an E/T ratio of 100:1. The data represent the means (± 1 SD) of percentage of specific killing from 2 replicate mice each group, and triplicate wells were set in vitro with less than 5% SE.