Therapeutic potency of anti–4-1BBL and anti-CD27 mAb against lymphoma. Mice (5 per group) received injections of (A) 2 × 10⁷ BCL₁ cells or (B) 2 × 10⁷A31cells intravenously on day 0 and then on days 4, 5, 6, and 7 treated with control IgG, anti-CD40, or anti-CD27 mAb (250 μg/d; intravenously day 4, intraperitoneally days 5, 6, and 7). Mice were monitored for tumor development. Survival to the humane end point was plotted using the Kaplan-Meier method (right) and analyzed for significance using the log-rank test. Control versus anti-CD40– and anti-CD27–treated groups for both tumors, P < .005. The results represent 1 of 2 similar experiments.