(A) Mice harboring two A20 tumors were treated intratumorally in one of the tumors with either OX40L plus CD80 and CD86 mRNA-CARTs, OX40L plus IL-12 mRNA-CARTs, or OX40L plus IFNγ mRNA-CARTs. Tumor growth of both tumors and overall survival was monitored for 40 and 80 days, respectively. (B) Mice harboring two CT26 colon carcinoma tumors were treated intratumorally in one of the tumors with either OX40L plus CD80 and CD86 mRNA-CARTs, or control mRNA-CARTs. Tumor growth of both tumors and overall survival was monitored for 40 and 50 days, respectively. (C) Mice harboring one A20 tumor and one CT26 tumor were treated intratumorally in the A20 tumor with OX40L plus CD80 and CD86 mRNA-CARTs. Tumor growth was measured over the course of 20 days. (A-C) Mice with tumors >15mm in largest diameter were euthanized. Survival of OX40L plus CD80 and CD86, and OX40L and IL-12 mRNA-CART treated mice were compared to OX40L and IFNγ mRNA-CART treated mice. Survival significance was calculated using Log Rank (Mantel-Cox) test. Ns, not significant; *, P < 0.05; **, P < 0.01; ***, P < 0.001 ****, P < 0.0001. Data representative of 2 independent experiments.