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bioRxiv · 10.1101/2024.11.19.624390

Cellular behavior analysis from live-cell imaging of TCR T cell-cancer cell interactions

Abstract

T cell therapies, such as chimeric antigen receptor (CAR) T cells and T cell receptor (TCR) T cells, are a growing class of anti-cancer treatments. However, expansion to novel indications and beyond last-line treatment requires engineering cells dynamic population behaviors. Here we develop the tools for cellular behavior analysis of T cells from live-cell imaging, a common and inexpensive experimental setup used to evaluate engineered T cells. We first develop a state-of-the-art segmentation and tracking pipeline, Caliban, based on human-in-the-loop deep learning. We then build the Occident pipeline to collect a catalog of phenotypes that characterize cell populations, morphology, movement, and interactions in co-cultures of modified T cells and antigen-presenting tumor cells. We use Caliban and Occident to interrogate how interactions between T cells and cancer cells differ when beneficial knock-outs of RASA2 and CUL5 are introduced into TCR T cells. We apply spatiotemporal models to quantify T cell recruitment and proliferation after interactions with cancer cells. We discover that, compared to a safe harbor knockout control, RASA2 knockout T cells have longer interaction times with cancer cells leading to greater T cell activation and killing efficacy, while CUL5 knockout T cells have increased proliferation rates leading to greater numbers of T cells for hunting. Together, segmentation and tracking from Caliban and phenotype quantification from Occident enable cellular behavior analysis to better engineer T cell therapies for improved cancer treatment.

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BibTeXRIS

Verma, A., Yu, C., Bachl, S., Lopez, I., Schwartz, M. S., Moen, E., Kale, N., Ching, C., Miller, G., Dougherty, T., Pao, E., Graf, W., Ward, C., Jena, S. G., Marson, A., Carnevale, J., Van Valen, D. A., Engelhardt, B. E.. 2024-11-21. Cellular behavior analysis from live-cell imaging of TCR T cell-cancer cell interactions. https://doi.org/10.1101/2024.11.19.624390

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