Abstract Description Tumor-Infiltrating Lymphocytes (TILs) Immunotherapy uses multiple strategies to expand tumor-specific T cells ex-vivo. Effective expansion is crucial to enhance therapeutic efficacy. Traditional manufacturing processes are time-consuming and require high doses of IL-2, which can compromise quality and functionality of TILs. We aimed to improve TIL expansion across various solid tumors, including prostate cancer, where previous methods fail from poor immunogenicity. TILs were isolated from human prostate, melanoma, ovarian and lung tumor biopsies, and were programmed in a preformulated cytokine mixture for 6 days prior to rapid expansion using a G-REX system. The expansion process was monitored by flow cytometry. Additionally, TILs were re-stimulated or co-cultured with tumor cell lines and functionality was assessed by cytokine release. Our 30-day protocol expanded 0.4-1.5 million TILs from human tumor tissue to around 8-10 billion functional TILs, achieving greater than 2000-fold expansion. Expanded TILs retained over 95% viability and robust production of IFNγ upon re-stimulation, indicating the preservation of functional potency. Our 30-day expansion protocol successfully generates large quantities of highly functional TILs from multiple different tumors including characteristically ‘cold’ solid tumors. This approach holds significant promise for enhancing the efficacy of TIL-based immunotherapies and offers a scalable solution for clinical applications. Funding Sources NIH 5TL1 TR001451, NIH 2R42CA239952. MUSC Translational Science Lab, MUSC Flow Cytometry Core Topic Categories Tumor Immunology: Checkpoints, Prevention, and Treatment (TIPT)
Mills et al. (Sat,) studied this question.