Recently, immunotherapeutic modalities with engineered cells and monoclonal antibodies have been effective in treating several malignancies. However, growing evidence suggests that immune-related adverse events (irAE) lead to severe and long-term side effects. Most iRAEs involve prolonged circulation of antibodies. To address this problem, nucleic acid aptamers can serve as alternative molecules to design immunotherapeutics with high functional diversity and predictable circulation times. Here, we report the first synthetic prototype consisting of DNA aptamers, which can activate T-cell receptor cluster of differentiation 3 (TCR-CD3) complex in cultured T-cells. We show that activation potential is similar to that of a monoclonal antibody (mAb) against TCR-CD3, suggesting the potential of aptamers in developing efficacious synthetic immunomodulators. The synthetic prototype of anti-TCR-CD3ε, as described herein, was designed using aptamer ZUCH-1 against TCR-CD3ε, generated by Ligand Guided Selection (LIGS). Aptamer ZUCH-1 was truncated and modified with nuclease-resistant RNA analogs to enhance stability. Several dimeric analogs with truncated and modified variants were designed with variable linker lengths to investigate the activation potential of each construct. Among them, dimeric aptamer with approximate dimensions similar to those of an antibody showed the highest T-cell-activation, suggesting the importance of optimizing linker lengths in engineering functional aptamers. The observed activation potential of dimeric aptamers shows the vast potential of aptamers in designing synthetically versatile immunomodulators with tunable pharmacokinetic properties, expanding immunotherapeutic designs with the use of nucleic acid-based ligands such as aptamers.

中文翻译：

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由配体引导的选择产生的同型二聚体适体变体激活分化三复合物的T细胞受体簇

近来，用工程细胞和单克隆抗体的免疫治疗方法已经有效地治疗了几种恶性肿瘤。但是，越来越多的证据表明，免疫相关的不良事件（irAE）会导致严重和长期的副作用。大多数iRAE涉及抗体的延长循环。为了解决这个问题，核酸适体可以用作替代分子以设计具有高功能多样性和可预测的循环时间的免疫疗法。在这里，我们报告的第一个合成原型由DNA适体组成，可以在培养的T细胞中激活分化3（TCR-CD3）复合物的T细胞受体簇。我们表明激活潜力类似于针对TCR-CD3的单克隆抗体（mAb）的激活潜力，提示适体在开发有效的合成免疫调节剂中的潜力。如本文所述，使用由配体指导选择（LIGS）产生的针对TCR-CD3ε的适体ZUCH-1设计抗TCR-CD3ε的合成原型。将适体ZUCH-1截短并用耐核酸酶的RNA类似物修饰以增强稳定性。设计具有可变的接头长度的几种具有截短的和修饰的变体的二聚体类似物，以研究每种构建体的活化潜力。其中，具有与抗体相似的近似尺寸的二聚体适体显示出最高的T细胞活化，表明在工程功能适体中优化接头长度的重要性。