Journal: Frontiers in Immunology
Article Title: IL-12-armed oncolytic HSV-2 enhances CAR T cell efficacy against pancreatic cancer in xenografted models
doi: 10.3389/fimmu.2025.1664289
Figure Lengend Snippet: Mesothelin chimeric antigen receptor (CAR)-T cells SS1-ICOSBBZ-CAR-T showed specific and modest anti-tumor capacity in vitro and in vivo . (A) Schematic diagram of the CAR structure. We constructed a third-generation MSLN-targeted CAR-T. This CAR incorporates the single-chain variable fragment (scFv) derived from the SS1 antibody for MSLN recognition, an ICOS-derived transmembrane domain, the intracellular domains contained two co-stimulatory molecules ICOS and 4-1BB, and the T cell receptor ζ (TCR-ζ) signaling domain. (B) Percentage of CAR positive T cells at day 12 (left) and CD4+ and CD8+ subsets (right) composition of the final CAR-T cell product. The CAR was stained by human mesothelin protein conjugated to PE. (C) Specific cytolytic activity of SS1-ICOSBBZ-CAR-T cells in vitro using luciferase assay. CAR-T cells were incubated with tumor cell lines for 30 hours at different E:T ratio. Panc-1-luc (mesothelin negative, left), Capan-2-luc (mesothelin positive, middle), Panc-1-luc-MSLN (mesothelin positive, right). (D) Schematic timeline of the antitumor efficacy experiment design. 2 × 10 6 Capan-2-luc cells were subcutaneously inoculated (s.c.) into the right flank of six-week-old B-NDG mice, tumors were established for 10 days prior to treatment initiation. Then, SS1-ICOSBBz-CAR-T cells or PBS (200 μL control) were administered via tail vein injection, (n = 5). (E) Bioluminescence imaging of mice at indicated days after treatment. (F) Quantification of tumor burden dynamics following CAR-T therapy. Tumor volume was monitored weekly during 35 days, and tumor volume changes were calculated relative to baseline (Day 0 set as 0% change). The tumor size at day 7 served as the reference for weekly measurements. Statistical significance of volume changes was assessed using t-test (n = 5 per group). (G) Body weight of mice treated with SS1-ICOSBBZ-CAR-T cells were measured. All data are presented as means ± standard deviation. *P < 0.05, **P < 0.01.
Article Snippet: After 24 h recovery, SS1-ICOSBBZ-CAR-T cells were co-cultured with Capan-2 target cells at E:T = 2:1 for 48 h. CD4 + and CD8 + subsets were separated using the human CD8 MicroBeads (Miltenyi), stained with AF647-conjugated antibodies (IsoPlexis,STAIN-1002–1 and STAIN-1003-1), loaded onto IsoLight chips (IsoPlexis), and analyzed using IsoSpeak v3.0.1.
Techniques: In Vitro, In Vivo, Construct, Derivative Assay, Staining, Activity Assay, Luciferase, Incubation, Control, Injection, Imaging, Standard Deviation