Abstract 4028: Analysis and recovery of functionally defined single immune cell clones through opto-electro-positioning technology

Cancer patients mount protective innate and adaptive immune responses against tumor cells. Such responses are able to control or even eliminate tumor burden if harnessed properly. Identifying clonal adaptive immune cells targeting tumor cells with designated function is extremely valuable as these cells are able to either fight the tumor directly or provide tumor targeting immune receptors to engineer other effector cells like autologous CD8 T cells or NK cells. The process of isolating cancer specific immune cells and their receptors, however, remains technically challenging and labor intensive. Opto-Electro-Positioning (OEP) technology employs a light actuated dielectrophoretic force to maneuver live cells in their culture environment. We have combined OEP with a nanofluidic cell culture system to produce an integrated microfluidic platform that enables multi-dimensional investigation of lymphocyte specificity and function. The system is able to 1) deterministically capture designated lymphocytes, 2) actively maintain and observe colony growth, and 3) conduct cytokine release assays, all in a single enclosed microfluidic chip. The new platform is suitable for high throughput screening to identify and harvest antigen specific and/or functionally defined T cells. We have successfully applied it to isolate primary human T cells targeting either EBV/Tetanus toxin antigens or tumor associated antigens such as MART-1 through tetramer staining or a proliferation assay. The system is also exceptionally efficient for investigating immune cells from clinical specimens typically of low cellularity. From tumor biopsies, we are able to capture tumor infiltrating T cells, stimulate proliferation, investigate their TNF-α secretion on chip, and obtain full transcriptomic analysis after export. Overall, our data suggest the OEP nano-fluidic environment provides a powerful high throughput screening tool to identify rare lymphocytes against tumor associate antigens or neo-antigens and to investigate precious clinical samples for biomarker discovery. Citation Format: Xiaohua Wang, Yelena Bronevetsky, Kristin Beaumont, Guido Stadler, Xiaoyan R. Bao, Duane Smith, Peter Beemiller, Kevin Chapman. Analysis and recovery of functionally defined single immune cell clones through opto-electro-positioning technology [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4028. doi:10.1158/1538-7445.AM2017-4028