Suppression of growth of preexisting tumors and survival of mice with preexisting tumors by intratumoral administration of AdmCD40L-modified DCs.
(A) Tumor growth, CT26 tumors, Balb/c mice. Tumor cells (2 × 105) were implanted subcutaneously in the midflank. On day 8, tumor-bearing mice were treated by intratumoral injection of 2 × 106 bone marrow DCs modified by in vitro infection with AdmCD40L (▪), AdNull (□), or PBS alone (Δ) (vector moi 40, 24 hours). (B) Survival, CT26 tumors, Balb/c mice. Shown is the survival of animals in panel A. (C) Tumor growth, B16 tumors, C57Bl/6 mice. The study was similar to that in panel A, but 5 × 105 tumor cells were used. (D) Survival, B16 tumors, C57Bl/6 mice. Similar to B, using mice in panel C. For panels A and C, the size of each tumor was assessed 3 times per week, and is reported as the average tumor area (mm2) ± standard error of n = 5 per group. Asterisks in panels A and C indicate significant differences at 95% confidence limits between AdmCD40L and all other surviving groups; on days 22 and 25 in panel A, AdmCD40L-infected DCs had no significant effect compared with mock-infected DCs. For panels B and D, survival was recorded as the percentage of animals in each group (Kaplan-Meier analysis, for all panels, P < .05 AdmCD40L compared with all other groups). In all panels, controls included tumor-bearing mice without any treatment (‘).
