Abstract 4216: Indication agnostic evaluation of CAR T cell function using patient-derived immunocompetent tumoroid modelling platform

Abstract Introduction: Engineered T cells redirected towards tumor-specific cytotoxicity is a promising immunotherapeutic modality that has been well characterized for efficacy against B cell malignancies and evaluated in multiple tumor types. However, the development and optimization of CAR T cell therapies requires a rigorous preclinical model for the evaluation of CAR T cell function, tumor killing, cytokine production, and memory responses. Experimental Procedure: We are evaluating our model platform Custom Organoid Modelling Platform for Accurate and Speedy SolutionS (COMPASS 2) as a comprehensive platform for testing developmental and functional stages of CAR T cells including activation, memory, and exhaustion. We are performing qualitative and quantitative analyses of surface markers to recapitulate the complexity of human cancer. Additionally, since CAR T cells mediate crosstalk with other immune components in the TME, we also evaluate and monitor the presence of B cells, NK cells, macrophages, and endogenous T cells. Triple Negative Breast Cancer (TNBC) ; Immunophenotyping (IP) ; Immunofluorescence (IF) ; Fluorescence Activated Cell Sorting (FACS) ; T regulatory (Treg). Summary of Results: Our evaluation of COMPASS 2 for functional testing of CAR T cells demonstrates the feasibility of the platform in preclinical CAR T cell evaluation. We showed T cell infiltration and analyzed cytokine production that may alter tumor cells and TME. Crosstalk with other immune cells will be evaluated. We are currently evaluating the tumor volume changes using an EGFRvIII-targeted CART cell therapy on TNBC model systems, followed by apoptosis and EGFR analysis using FACS. Conclusion: Our COMPASS 2 model platform enables studies that require recapitulating hurdles to CAR therapy, including antigen escape, T cell dysfunction and trafficking; to reveal an essential role of the endogenous immune response mediating the antitumor effect following CAR therapy. Citation Format: Damieanus O. Ochola, Huckie Dell Mundo, Preethi Samuel, Natalia Korkorina, Bhuvanesh Dave. Indication agnostic evaluation of CAR T cell function using patient-derived immunocompetent tumoroid modelling platform 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 4216.