Generation of neoantigen-specific T cells for adoptive cell transfer for treating head and neck squamous cell carcinoma

Abstract

Adoptive cell therapy using TCR-engineered T cells (TCR-T cells) represents a promising strategy for treating relapsed and metastatic cancers. We previously established methods to identify neoantigenspecific TCRs based on patients' PBMCs. However, in clinical practice isolation of PBMCs from advanced-stage cancer patients proves to be difficult. In this study, we substituted blood-derived T cells for tumor-infiltrating lymphocytes (TILs) and used an HLA-matched cell line of antigenpresenting cells (APCs) to replace autologous dendritic cells. Somatic mutations were determined in head and neck squamous cell carcinoma resected from two patients. HLA-A*02:01-restricted neoantigen libraries were constructed and transferred into HLA-matched APCs for stimulation of patient TILs. TCRs were isolated from reactive TIL cultures and functionality was tested using TCR-T cells in vitro and in vivo. To exemplify the screening approach, we identified the targeted neoantigen leading to recognition of the minigene construct that stimulated the strongest TIL response. Neoantigen peptides were used to load MHC-tetramers for T cell isolation and a TCR was identified targeting the KIAA1429 D1358E mutation. TCR-T cells were activated, exhibited cytotoxicity, and secreted cytokines in a dose-dependent manner, and only when stimulated with the mutant peptide. Furthermore, comparable to a neoantigen-specific TCR that was isolated from the patient's PBMCs, KIAA1429 D1358E -specific TCR T cells destroyed human tumors in mice. The established protocol provides the required flexibility to methods striving to identify neoantigen-specific TCRs. By using an MHC-matched APC cell line and neoantigen-encoding minigene libraries, autologous TILs can be stimulated and screened when patient PBMCs and/or tumor material are not available anymore.Abbreviations: Head and neck squamous cell carcinoma (HNSCC); adoptive T cell therapy (ACT); T cell receptor (TCR); tumor-infiltrating lymphocytes (TIL); cytotoxic T lymphocyte (CTL); peripheral blood mononuclear cell (PBMC); dendritic cell (DC); antigen-presenting cells (APC)

TCR engineered T cells for solid tumor immunotherapy

“…Recently, Wei et al constructed an HLA-A*02:01-restricted neoantigen library, which was transferred into HLA-matched APCs to stimulate T cells from the peripheral blood of patients. This group then screened and constructed a neoantigen-specific TCR targeting the KIAA1429D1258E mutation, and these TCR-T cells showed efficiency in killing human head and neck squamous cell carcinoma in mice [ 50 ]. This result provided a new strategy for screening mutant neoantigen-specific TCRs under conditions where it is difficult to obtain tumor tissue.…”

Current status and perspective of tumor immunotherapy for head and neck squamous cell carcinoma

“…Another study analyzed 43 patients with HNSCC who received chemotherapy after radical tumor surgery, 21 of whom were included in the experimental group treated with ACT achieved a higher survival benefit (Jiang et al, 2015). Wei et al (2021) isolated and cultured TILs from fresh tumor tissue of eight HNSCC patients and demonstrated the feasibility of isolating neoantigen-specific T cells from TILs. Moreover, researchers Although TILs are usually safe, there are potential clinical risks such as on-target off-tumor toxicity, off-target reactivity, and cytokine-release syndrome (Casucci et al, 2015;Rapoport et al, 2015).…”

dbPepNeo2.0: A Database for Human Tumor Neoantigen Peptides From Mass Spectrometry and TCR Recognition

“…Eight patients with head and neck squamous cell carcinoma (HNSCC) were predicted to produce 113 candidate neoantigens; these 113 candidate neoantigens have been proved using TCR T cells, and two neoantigens have been proved to activate T cells to some extent ( 47 ). We obtained the data directly from the published literature without reperforming original data reanalysis.…”