Abstract 4014: Humanized mouse model to assess PBMC donor derived autologous CD19 CAR Ts for efficacy against Raji tumors and related cytokine release

Abstract Immuno-oncology cell therapies engage the immune system to treat cancer. In recent years, adoptive T-cell therapy with CD19-specific chimeric antigen receptors (CARs) has shown promise for treatment of various malignancies, including acute lymphoblastic leukemia. However, CAR-T-cell therapies have been hampered by various adverse events, including cytokine release syndrome (CRS). To predict and minimize CRS effects from CAR-T therapies, a human immune preclinical murine model that combines efficacy and toxicity readouts is essential. Here, we describe the development of PBMC humanized mouse model based on the NSG-MHC I/II-DKO strain to study autologous CD19 CAR-T treatment related tumor growth inhibition and CRS in vivo. Three different PBMC donors were used to generate CAR-T (CD28-Cd3z) directed against a CD19 epitome. Our preliminary data demonstrate that CD19 CAR-T treatment stimulated dynamic and PBMC donor dependent cytokine release with IFN-g, IL-10, IL-4, IL-2, IL-6 and TNF. Our model showed elevation of shared proinflammatory cytokines (IFN-g, IL-10, IL-2 and TNF) observed in humans after CD19 CAR-T treatment. Currently, we are evaluating our PBMC based cytokine release model in CD19 CAR-T cells tumor control study. Our results to date indicate that PBMC-engrafted NSG-MHC I/II-DKO mouse models are vital platforms to screen adoptive T-cell therapy for potential CRS. Citation Format: Senthil Ramalingam, Danying Cai, Lindsay Shopland, James G. Keck. Humanized mouse model to assess PBMC donor derived autologous CD19 CAR Ts for efficacy against Raji tumors and related cytokine release 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 4014.