Therapeutic effect of rituximab after EL4-huCD20-Luc lymphoma cell inoculation. Mice were inoculated with 8 × 103 EL4-huCD20-Luc intravenously and then administered 6 mg/kg rituximab (■) or PBS (△) the day after (D1) or administered different doses (6, 12, 20, or 40 mg/kg) of rituximab on preestablished lymphoma tumor on day 13 (D13). Tumor growth and mice survival were evaluated by BLI on D9, D13, and then twice a week until the death of the mice. (A) Compared with control group, in vivo lymphoma growth was completely abrogated by administration of 6 mg/kg rituximab on D1 (significantly different P < .001). (B) Mice administered rituximab on D1 showed a significantly increased survival compared with the control group (P < .05). (C) PCR analysis on liver, lymph nodes, and bone marrow showed a disappearance of EL4-huCD20-Luc as early as 4 weeks after the infusion of rituximab on D1. (D) Mouse survival was significantly increased after infusion of 12, 20, or 40 mg/kg of rituximab on D13. *Significant difference, P < .05; 6 mg/kg rituximab did not modify mouse survival; P > .05.
