Kinetics And Potency Of T Cell-Mediated Cytolysis Of Glioblastoma

Abstract Glioblastoma is an aggressive brain cancer with no effective treatments and a prognosis of 12–15 months. Immune system effector T cells are a promising therapy due to their high specificity and innate cytotoxicity. Assessing the efficacy and potency of T cell therapies in vitro and with high throughput is vital for development of this promising therapy. Cellular impedance-based assays offer sensitive, label-free, and continuous monitoring of cell proliferation and immune cell-mediated cytotoxicity, revealing both the potency and kinetics of T cell killing. Here, we investigated the targeting potency of activated human T cells on human U87MG glioma and patient-derived glioma cells. U87MG and patient-derived glioma cells were plated at densities ranging from 10k to 50k cells per well on a PDL-coated CytoView-Z 96-well plate (n=12 wells per density). After 24 hours, activated patient-derived T Cells (ImmunoCult CD3/CD28 activation media) were added in a 10:1 effector:target ratio. Impedance and cytolysis were continuously monitored for over 120 hours. As expected, higher densities of glioma cells proliferated faster and reached a higher impedance level at 24 hours. Addition of activated human T cells resulted in a decrease in impedance consistent with T cell-mediated lysis of the glioma cells. The highest density of T cells (500k) exhibited the fastest rate of U87 cytolysis, with a Kill Time 50 of 35 hours. All densities reached 100% cytolysis by 100 hours. Overall, activated human T cells were highly effective for cytolysis of U87MG and patient-derived glioma cells. The cellular impedance assay revealed high potency, with kinetics that varied across cell densities despite the same effector:target ratios.