Engineering antigen-specific tumor-infiltrating lymphocytes for adoptive cell therapy of HNSCC

Project Summary/Abstract: Adoptive cell transfer (ACT) with tumor-infiltrating lymphocytes (TIL) has demonstrated a 28-55% response rate in metastatic melanoma patients, leading to recent FDA approval. Head and neck squamous cell carcinoma (HNSCC) is responsive to immunotherapeutic strategies yet the antigen-specific T cell repertoire and its therapeutic potential remain underexplored. The overall objective of this proposal is to systematically investigate the role of antigen-reactive TIL (Ag-TIL) in mediating immune responses to HNSCC and to design TIL products able to overcome mechanisms of immunotherapeutic resistance. We hypothesize that Ag-TIL are a distinct subset of the T cell infiltrate instrumental to the effectiveness of ACT and that engineering dysfunctional TIL is an effective means to restore anti-tumor immunity. We will 1) define the mechanisms of antigen-specific TIL-mediated anti-tumor immunity in HNSCC and 2) engineer dysfunctional HNSCC TIL to overcome immune resistance mechanisms. In Aim 1, this study will functionally evaluate tumor-reactive HNSCC TIL and investigate the antigenic determinants, cellular interactions, and molecular signature of these T cells via next-generation sequencing, immunopeptidomics, spatial transcriptomics, and advanced immunologic assays. Aim 2 will develop T cell engineering strategies, including CRISPR/Cas9 and T cell receptor transgenic (TCR-) TIL, to overcome TCR-MHC-mediated mechanisms of resistance to immunotherapy. Findings will be validated in murine models of HNSCC to ensure translational potential. The results of this study will provide a deep understanding of TIL biology in the therapeutic setting and will generate novel cellular therapy products. Dr. Hall will undergo an intensive scientific training in HNSCC biology and T cell engineering that will prepare him for a successful career as an independent investigator, while maintaining strong collaborations in immunopeptidomics, spatial transcriptomics, computational biology, and translational immunology. During the K99 phase, this training will be fully supported by his mentor, Dr. Shari Pilon-Thomas, and co-mentor, Dr. Christine Chung, as well his Advisory Committee, collaborators, and the institution, Moffitt Cancer Center. Dr. Hall’s training program is designed to foster his career development towards becoming an independent investigator with a focus on 1) a comprehensive cell therapies foundation, 2) mentorship and leadership skills, 3) intellectual property development, and 4) written and verbal communication skills. Drs. Pilon-Thomas and Chung will meet with Dr. Hall bi-weekly to provide guidance on experimental design, data analysis and career development. Dr. Hall will also meet with his Advisory Committee twice yearly for insight into the progress of his project and professional goals during the K99 phase. Dr. Hall’s mentorship team will assist with finding, interviewing, and negotiating a junior faculty position. Dr. Hall has the full support of his mentor and co-mentor and the ability to take all of the proposed work with him to establish his own scientific program as an independent investigator in the R00 phase of this award.