Fig. 3
From: Avidity characterization of genetically engineered T-cells with novel and established approaches
Real time analysis of TCR T-cell binding to peptide-presenting target cells. LigandTracer® (a) was used to assess the binding of pp65-TCR and TARP-TCR-engineered human T-cells to HLA-A2 positive target cells (mel526) presenting the cognate peptide (b). Target cells were adhered over-night to one side of a Petri dish and then pulsed with either TARP4–13 (10 μM] or pp65495–503 (10 nM). Sorted and expanded pp65-TCR and TARP-TCR-engineered T-cells were labeled with CFSE and washed before being added to the dish with peptide-pulsed target cells. Binding of TCR-engineered T-cells to peptide-pulsed target cells was measured in real time for 90 min using 1.5 × 105 T-cells and an additional 90 min using 4.5 × 105. Binding kinetics in terms of fluorescence signal from target cells is shown for pp65-TCR T-cells (c), with proportional increase of signal when three times more T-cells were added (d), and representation of the binding slope (e). Binding kinetics in terms of fluorescence signal from target cells is shown for TARP-TCR T-cells (f), with proportional increase of signal when three times more T-cells were added (g), and representation of the binding slope (h)