Figure 7.

Improved therapeutic efficacy of intratumoral injections with gp75-recognizing CAR T cells following scIL-12/DRIL18 mRNA electroporation

(A) Intracellular IL-12 protein expression following electroporation of the indicated mRNAs into anti-gp75 mouse CAR T cells. MFIs are provided in the bar graph.

(B) IFN-γ concentrations over time in the indicated CAR T cell cultures, including the mixes of DRIL18 and scIL-12 CAR T cells.

(C and D) Ex vivo cytotoxicity performed over time with the indicated mRNA-electroporated CAR T cells at a 1:4 ratio against gp75-transfected B16-OVA (C) and non-transfected B16-OVA (D).

(E) Scheme of the experiments of mice bearing bilaterally B16-OVA tumors and treated intratumorally with the different mRNA-electroporated CAR T cells or the scIL-12/DRIL18 mixture.

(F) Tumor size follow-up of CAR T-injected and contralateral non-injected tumors with the indicated mRNA-electroporated or mock CAR T cells. Survival of the treatment groups of mice is provided.

Experiments were repeated twice, and statistical comparisons were made with one-way ANOVA tests (A and B), two-way ANOVA tests, and log rank tests to compare tumor growth and survival, respectively. Biological duplicates were performed in experiments (B)–(D). For antitumor efficacy experiments (E and F), we randomly assigned six mice per group. Data are represented as mean ± SD. See also Figure S9.

The significance is represented with asterisks (^∗) according to the following values: p<0.05 (^∗), p<0.01(^∗∗), p<0.001(^∗∗∗) and p<0.0001(^∗∗∗∗).