Antigen discovery technologies have largely focused on major histocompatibility complex (MHC) class I-restricted human T cell receptors (TCRs), leaving methods for MHC class II-restricted and mouse TCR reactivities relatively undeveloped. Here we present TCR mapping of antigenic peptides (TCR-MAP), an antigen discovery method that uses a synthetic TCR-stimulated circuit in immortalized T cells to activate sortase-mediated tagging of engineered antigen-presenting cells (APCs) expressing processed peptides on MHCs. Live, tagged APCs can be directly purified for deconvolution by sequencing, enabling TCRs with unknown specificity to be queried against barcoded peptide libraries in a pooled screening context. TCR-MAP accurately captures self-reactivities or viral reactivities with high throughput and sensitivity for both MHC class I-restricted and class II-restricted TCRs. We elucidate problematic cross-reactivities of clinical TCRs targeting the cancer/testis melanoma-associated antigen A3 and discover targets of myocarditis-inciting autoreactive T cells in mice. TCR-MAP has the potential to accelerate T cell antigen discovery efforts in the context of cancer, infectious disease and autoimmunity.

抗原发现技术主要集中在主要组织相容性复合物 (MHC) I 类限制性人类 T 细胞受体 (TCR) 上，而 MHC II 类限制性和小鼠 TCR 反应性的方法相对尚未开发。在此，我们介绍抗原肽的 TCR 作图 (TCR-MAP)，这是一种抗原发现方法，该方法使用永生化 T 细胞中的合成 TCR 刺激电路来激活在 MHC 上表达加工肽的工程抗原呈递细胞 (APC) 的分选酶介导的标记。活的、标记的 APC 可以通过测序直接纯化以进行反卷积，从而能够在汇集的筛选环境中针对条形码肽库查询具有未知特异性的 TCR。 TCR-MAP 可准确捕获 MHC I 类限制性和 II 类限制性 TCR 的自身反应性或病毒反应性，具有高通量和灵敏度。我们阐明了针对癌症/睾丸黑色素瘤相关抗原 A3 的临床 TCR 的有问题的交叉反应性，并发现了小鼠中引发心肌炎的自身反应性 T 细胞的靶标。 TCR-MAP 有潜力加速癌症、传染病和自身免疫领域 T 细胞抗原的发现工作。