DEVELOPING A HIGH THROUGHPUT ASSAY TO INVESTIGATE CHEMICAL AGENTS WHICH SENSITIZE TUMOUR CELLS TO KILLING BY CAR ENGINEERED T CELLS

Abstract

Cancer immunotherapy is emerging as a powerful tool in the treatment of cancer. Multiple clinical trials have established that infusion of tumour-specific T cells can cause regression of advanced tumours and prevent tumour relapse. While tumour-specific T cells are typically rare, engineering methods have been developed to introduce tumour-specific receptors into T cells and engender peripheral blood T cells with the ability to kill tumour cells. These engineering successes notwithstanding, tumour cells demonstrate variable sensitivity to T cell attack. Therefore, to maximize the impact of the engineered T cells, it is necessary to develop therapeutic strategies that render tumour cells sensitive to immune attack. For my thesis research, I sought to develop a high throughput screening assay that would allow me to screen chemical libraries for agents that sensitize tumour cells to T cell attack. My ultimate goal is to define chemical agents that effectively sensitize tumour cells to T cell attack but display a better toxicity profile than existing chemotherapies. To this end, I developed a screen where resistant tumour cells were exposed to T cells engineered with chimeric antigen receptors and positive hits were defined as agents that could enhance killing of the tumour cells. My work explored both murine and human systems and I ultimately decided to use human cells for my screen. Multiple methods for measuring tumour cell killing were evaluated, many tumour lines were screened and I optimized the conditions for generating large numbers of engineered T cells for the screen. The net result of my thesis work is a miniaturized assay that is ready for high throughput screening.