Abstract 1514: A novel workflow to assess the T-cell and patient-derived organoid interaction

Abstract Immunotherapy is increasingly popular as a type of cancer treatment. These therapies include the use of Chimeric Antigen Receptor-engineered T-cells (CAR T-cells), tumor-infiltrating lymphocytes (TIL), and other genetically modified T-cells to specifically target the cancer cells. Although much success has been achieved with immunotherapy for treatment of blood cancers, its efficacy remains limited in solid tumors. One of the reasons for the low success rate is attributed to the solid tumor microenvironment (TME) where suppressive cytokines limit the tumor killing ability of T-cells. Thus, understanding the role the TME plays in T-cell responses is essential for the development of effective cancer therapies. The benefits of using 3-dimensional (3D) PDOs lie in the physical and chemical cues present within the TME that cannot be mimicked in traditional 2D monolayer cultures. Studies show that PDOs show similar responses to drugs as original tumors, suggesting the value of using PDOs to improve therapeutic outcomes. Thus, PDOs can provide more relevant physiological and pathological cancer models that recapitulate the basic features of primary tumors and is more suited for assessing the effectiveness of T-cell killing than 2D cell models. Despite the benefits associated with the use of PDOs, there are significant barriers to widespread adoption of PDOs in drug discovery. Organoid production is a costly and highly labor-intensive process. Moreover, organoid culture is a skilled manual process, and thus there can be significant variability between operators. To address the challenges associated with the use of PDOs in large scale applications, a semi-automated bioprocess has been developed for the large-scale expansion of assay ready organoids. Here, we developed a method to assess the effectiveness of T-cell invasion in solid tumors using patient derive organoids (PDOs). Using bioreactor expanded patient-derived colorectal cancer organoids (CRCs), activated PBMCs (human peripheral blood mononuclear cells) stained with CellTracker were added to CRCs (stained with MitoTracker) in a 96well microtiter plate and monitored on every 4 hours for 3 days using high content imager. To quantify T-cell invasion, we developed an image analysis method to measure the distance of each T-cell to the nearest organoid (interaction distance). We find that stimulated T-cell resulted in smaller interaction distance than non-stimulated T-cells. The results demonstrate the utility of the bioreactor-expanded organoids in large scale T-cell based screens. Citation Format: Zhisong Tong, Angeline Lim, Oksana Sirenko. A novel workflow to assess the T-cell and patient-derived organoid interaction abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 1514.