Balance between host preconditioning and transferred cell dose determines the antitumor benefit provided by allogeneic T-bodies. Kaplan-Meyer survival plots of Renca-Her2/Neu-bearing mice. Mice (n = 12/group) were irradiated and then either left untreated as a control (blue diamonds), or systemically administered with syngeneic T-bodies (Balb-N29, purple squares) or allogeneic T-bodies (Black-N29, orange triangles). The results shown are pooled from 2 independent experiments. P values were computed for each experiment separately using the log-rank test, and combined using the Fisher method. (A) Protocol consisting of 200 rad irradiation and 30 × 10⁶ T-bodies (200R/30). Balb-N29 or Black-N29 vs control P = .000004. (B) Protocol consisting of 200 rad irradiation and 100 × 10⁶ T-bodies (200R/100). Balb-N29 or Black-N29 vs control P = .000004. (C) Protocol consisting of 400 rad irradiation and 30 × 10⁶ T-bodies (400R/30). Balb-N29 or Black-N29 vs control P = .000004. (D) Protocol consisting of 400 rad irradiation and 100 × 10⁶ T-bodies (400R/100). Balb-N29 vs control P = .000004. In this protocol, mice receiving the Black-N29 died from GVHD manifested by severe cachexia (supplemental Figure 1).