Fig. 4

TIGIT-28 enhances the function of high affinity TCR F5. a Primary human T-cells engineered to express the MART-1-specific high-affinity TCR F5. These cells were co-transduced with TIGIT-28 or a control gene (tr. CD34) were analyzed for TCR expression using a MART-1/HLA-A02 tetramer by flow cytometry. The dotted line represents the basal endogenous expression in the control population. The percentage of positive cells and the MFI (in brackets) are shown. b These cells were co-cultured with the indicated targets and analyzed for OX40 expression 24 h after the beginning of the co-culture. The percentage of OX40 positive cells (gated on the CD4+ population) and the MFI (in brackets) are shown in the left panels. These results are representative of four independent experiments (indicated in the right panel plots) with at least three donors and the difference between TIGIT-28 and control vector was found to be statistically significant (p < 0.05, calculated using a Student’s paired t-test). c-d These engineered T cells were separated into either CD4⁺ or CD8⁺ populations using magnetic beads. Separated cells were co-cultured with the indicated targets. The concentrations of TNFα (c) and IFNγ (d) secreted in the co-culture supernatant were detected by ELISA. Cytokine concentrations were normalized for each target cell line (with or w/o CD155) to the secretion observed in the positive control F5-TCR only group (for CD4⁺ cells - left panels: normalized to an average TNFα secretion of 19,863 pg/ml for 888A2 and 1802 pg/ml for 624.38. and to an average IFNγ secretion of 13,997 pg/ml for and 3876 pg/ml for 624.38; for CD8⁺ cells - right panels: normalized to an average TNFα secretion of 25,478 pg/ml for 888A2 and 3867 pg/ml for 624.38. and to an average IFNγ secretion of 21,249 pg/ml for 888A2 and 5696 pg/ml for 624.38). These results are averages of at least 5 independent experiments, performed with at least 3 different donors (*:p < 0.05, calculated using a Student’s paired t-test)