(1) Chatani PD (2) Lowery FJ (3) Parikh NB (4) Hitscherich KJ (5) Yossef R (6) Hill V (7) Gartner JJ (8) Paria B (9) Florentin M (10) Ray S (11) Bera A (12) Parkhust M (13) Robbins P (14) Krishna S (15) Rosenberg SA

Journal for immunotherapy of cancer

By using flow cytometry to sort T cells co-expressing PD-1, CD39, and TIGIT (TILTP) from tumor digests of metastatic epithelial cancers, Chatani et al. were able to detect and enrich neoantigen-reactive CD8+ T cells. Their results were comparable to those achieved with a single-cell transcriptomic approach, but used more readily available and affordable technology. While the sorted TILTP cells were highly enriched for tumor reactivity, they lacked proliferative capacity, and were unable to maintain reactivity through in vitro expansion processes, making them unsuitable as products for ACT. Instead, rapid TCR identification could be utilized in a TCR engineering approach.

Contributed by Lauren Hitchings

BACKGROUND: Cellular immunotherapies using autologous tumor-infiltrating lymphocytes (TIL) can induce durable regression of epithelial cancers in selected patients with treatment-refractory metastatic disease. As the genetic engineering of T cells with tumor-reactive T-cell receptors (TCRs) comes to the forefront of clinical investigation, the rapid, scalable, and cost-effective detection of patient-specific neoantigen-reactive TIL remains a top priority. METHODS: We analyzed the single-cell transcriptomic states of 31 neoantigen-specific T-cell clonotypes to identify cell surface dysfunction markers that best identified the metastatic transcriptional states enriched with antitumor TIL. We developed an efficient method to capture neoantigen-reactive TCRs directly from resected human tumors based on cell surface co-expression of CD39, programmed cell death protein-1, and TIGIT dysfunction markers (CD8(+) TIL(TP)). RESULTS: TIL(TP) TCR isolation achieved a high degree of correlation with single-cell transcriptomic signatures that identify neoantigen-reactive TCRs, making it a cost-effective strategy using widely available resources. Reconstruction of additional TIL(TP) TCRs from tumors identified known and novel antitumor TCRs, showing that at least 39.5% of TIL(TP) TCRs are neoantigen-reactive or tumor-reactive. Despite their substantial enrichment for neoantigen-reactive TCR clonotypes, clonal dynamics of 24 unique antitumor TIL(TP) clonotypes from four patients indicated that most in vitro expanded TIL(TP) populations failed to demonstrate neoantigen reactivity, either by loss of neoantigen-reactive clones during TIL expansion, or through functional impairment during cognate neoantigen recognition. CONCLUSIONS: While direct usage of in vitro-expanded CD8(+) TIL(TP) as a source for cellular therapy might be precluded by profound TIL dysfunction, isolating TIL(TP) represents a streamlined effective approach to rapidly identify neoantigen-reactive TCRs to design engineered cellular immunotherapies against cancer.

Author Info: (1) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. (2) Surgery Branch, Center for Cancer Research, N

Author Info: (1) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. (2) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA sri.krishna@nih.gov frank.lowery@nih.gov sar@mail.nih.gov. (3) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. (4) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. (5) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. (6) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. (7) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. (8) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. (9) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. (10) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. (11) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. (12) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. (13) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. (14) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA sri.krishna@nih.gov frank.lowery@nih.gov sar@mail.nih.gov. (15) Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA sri.krishna@nih.gov frank.lowery@nih.gov sar@mail.nih.gov.

Citation: J Immunother Cancer 2023 May 11: Epub

Link to PUBMED: http://www.ncbi.nlm.nih.gov/pubmed/37258038

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