High-throughput Screening of Human Tumor Antigen-specific CD4 T Cells, Including Neoantigen-reactive T Cells

• Published in: Clinical cancer research 2019-07, Vol.25 (14), p.4320-4331
• Main Authors: Costa-Nunes, Carla, Cachot, Amélie, Bobisse, Sara, Arnaud, Marion, Genolet, Raphael, Baumgaertner, Petra, Speiser, Daniel E, Sousa Alves, Pedro M, Sandoval, Federico, Adotévi, Olivier, Reith, Walter, Protti, Maria Pia, Coukos, George, Harari, Alexandre, Romero, Pedro, Jandus, Camilla
• Format: Article
• Language: English
• Subjects: Antigens, Neoplasm - blood; Antigens, Neoplasm - immunology; Cancer Vaccines - immunology; Case-Control Studies; CD4-Positive T-Lymphocytes - immunology; CD8-Positive T-Lymphocytes - immunology; High-Throughput Screening Assays; Humans; Immunotherapy; Melanoma - blood; Melanoma - immunology; Melanoma, Cutaneous Malignant; Peptide Fragments - immunology; Skin Neoplasms - blood; Skin Neoplasms - immunology
• ISSN: 1078-0432; 1557-3265
• DOI: 10.1158/1078-0432.CCR-18-1356

Characterization of tumor antigen-specific CD4 T-cell responses in healthy donors and malignant melanoma patients using an amplified T-cell library screening procedure. A high-throughput, human leukocyte antigen (HLA)-independent approach was used to estimate at unprecedented high sensitivity level precursor frequencies of tumor antigen- and neoantigen-specific CD4 T cells in healthy donors and patients with cancer. Frequency estimation was combined with isolation and functional characterization of identified tumor-reactive CD4 T-cell clones. In healthy donors, we report frequencies of naïve tumor-associated antigen (TAA)-specific CD4 T cells comparable with those of CD4 T cells specific for infectious agents ( ). Interestingly, we also identified low, but consistent numbers of memory CD4 T cells specific for several TAAs. In patients with melanoma, low frequencies of circulating TAA-specific CD4 T cells were detected that increased after peptide-based immunotherapy. Such antitumor TAA-specific CD4 T-cell responses were also detectable within the tumor-infiltrated tissues. TAA-specific CD4 T cells in patients displayed a highly polyfunctional state, with partial skewing to Type-2 polarization. Finally, we report the applicability of this approach to the detection and amplification of neoantigen-specific CD4 T cells. This simple, noninvasive, high-throughput screening of tumor- and neoantigen-specific CD4 T cells requires little biologic material, is HLA class II independent and allows the concomitant screening for a large number of tumor antigens of interest, including neoantigens. This approach will facilitate the immunomonitoring of preexisting and therapy-induced CD4 T-cell responses, and accelerate the development of CD4 T-cell-based therapies.