Abstract A020: The highly predictive 3D Cell Co-Culture Model for Immunotherapy studies

Abstract In the ever-evolving landscape of biomedical research, 3D Cell Culture (3DCC) systems have become essential for replicating in vivo environments and promoting more physiologically cellular interactions and microenvironment. 3DCC models can be beneficial in preclinical studies by reducing drug testing costs and minimizing the excessive use of animal models. This is especially significant in immuno-oncology research, where selecting an appropriate in vivo model poses challenges due to differences in protein structures across species and decisions regarding the use of humanized mouse models. 3DCC has the potential to represent fully human research models hence avoiding the complications of GvHD (graft versus host disease). In our study, we presented a potency of 3D co-culture of cancer RL95-2 endometrium cells and PBMCs and we indicated their use in further stages of immune-therapeutics testing. We also confirmed the phenomena that the 3D structures grow on top of the hydrogel making them accessible to both small molecules as well as large molecules like: antibodies, Antibody-Drug-Conjugates (ADCs), cytokines, CAR-T therapy, oncolytic viruses, that consists key technical advantage of our technics. We used protein-based hydrogel LifeGel® for creating 3D cell co-culture of cancer and immune cells. We demonstrated the new in vitro model on which the potency of immune checkpoint inhibitors, was verified. In our assay we verified the potential of therapeutic antibodies used in the clinic: atezolizumab (anti PD-L1) and onvatilimab (anti-VISTA), and also newly-developed bi-speccifics antibodies. After the co-culture with PBMCs in the presence of tested immunotherapeutics, the viability of cancer cells was evaluated using colorimetric assay. The morphological parameters of tumor spheroids after co-culture with immune cells were assessed using AnaSP software. It should be underlined that our 3DCC study showed more clinically predictive testing results when comparing to other pre-clinical models. Furthermore, we confirmed that not only immortalized cancer cells but also 3D structures of patient-derived tumoroids or patient-derived xenograft models may be used in co-culture with immune cells for drug screening and immuno-testing purposes. We also confirmed the phenomena that the 3D structures grow on top of the hydrogel making them accessible to both small molecules as well as large molecules like: antibodies, Antibody-Drug-Conjugates (ADCs), cytokines, CAR-T therapy, oncolytic viruses, etc. In the realm of cancer research, 3D cell cultures showcase a predictive power in assessing the mechanistic effects and anticancer effects of drugs that rivals traditional in vivo research models. LifeGels® biophysical parameters can be modified: hardness, density and elasticity, creating an environment adapted to every characteristic of cancer cells, making them accessible to immune cells evasion. The unique property of our approach is to use 3DCC in immune-oncology research as high-throughput screening (HTS), high-content analysis and fully-automated processing. Citation Format: Justyna Kocik-Krol, David Earnshaw, Marcin Krzykawski. The highly predictive 3D Cell Co-Culture Model for Immunotherapy studies [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor Immunology and Immunotherapy; 2024 Oct 18-21; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2024;12(10 Suppl):Abstract nr A020.