Abstract A067: A patient-derived 3D MicroOrganoSpheres® (MOS®) platform to evaluate functional potency of autologous TILs in Non-Small Cell Lung Cancer (NSCLC)

Abstract Background and Aim: Evaluating the efficacy of adoptive cell therapies in solid tumors is fundamentally challenging due to tumor heterogeneity, scarcity of autologous patient material, and the failure of traditional in vitro models to recapitulate the tumor microenvironment. The MicroOrganoSpheres® (MOS®) technology overcomes these limitations by generating automated, high-throughput, droplet-based 3D patient-derived organoid models from small patient samples enabling functional testing within a clinically relevant timeframe. The aim of this study was to demonstrate the feasibility of using the MOS system to functionally assess autologous Tumor-Infiltrating Lymphocyte (TIL) potency in Non-Small Cell Lung Cancer (NSCLC). Methods: MOS droplets were generated from resected NSCLC tumor samples with the MOSgen™ instrument, a proprietary automated droplet microfluidics device, and NSCLC MOS models were established. Autologous TILs were simultaneously established from the same tumor samples. NSCLC MOS were co-cultured with the autologous TIL product across a range of Effector:Target (E:T) ratios. TIL potency was quantified using two orthogonal readouts: (1) longitudinal high throughput confocal imaging to monitor and quantify tumor cell dynamics (epithelial proliferation/death) and (2) spectral flow cytometry to measure epithelial cell killing and characterize the tumor-reactive TIL phenotype post-culture. Results: MOS models containing well-established and viable organoids were successfully generated from NSCLC patient samples. Autologous TILs were expanded and phenotypically profiled. Co-culture of NSCLC MOS models with autologous TILs resulted in a significant, dose-dependent increase in TIL-mediated tumor killing, evidenced by a marked decrease in epithelial cell proliferation and an increase in epithelial death, which was detectable as early as 24hr, and confirmed by both imaging and flow cytometry. Post-co-culture analysis by flow cytometry facilitated detailed phenotypic profiling of the TIL product, allowing for the assessment of general activation/exhaustion status and the identification and characterization of tumor-reactive TIL subsets. Conclusion: The MicroOrganoSpheres® platform offers a powerful and highly translatable ex vivo tool to evaluate the potency of adoptive cellular therapies, such as TILs, against NSCLC and other solid tumors. Citation Format: Laura Contreras-Ruiz, David Graham, Jacob Layton, Madison Rivera, Aaron K. McCormick, Kendra Hightower. A patient-derived 3D MicroOrganoSpheres® (MOS®) platform to evaluate functional potency of autologous TILs in Non-Small Cell Lung Cancer (NSCLC) [abstract]. In: Proceedings of the AACR Immuno-Oncology Conference (AACR IO): Discovery and Innovation in Cancer Immunology: Revolutionizing Treatment through Immunotherapy; 2026 Feb 18-21; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Immunol Res 2026;14(2 Suppl):Abstract nr A067.