van der Wulp Willemijn, Remst Dennis F G, Koster Carli S, Wouters Anne K, Ressing Maaike E, Schuurman Janine, van Kasteren Sander I, Bleijlevens Boris, Hoeben Rob C, Guelen Lars, Heemskerk Mirjam H M
Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands.
Department of Hematology, Leiden University Medical Center, Leiden, The Netherlands.
Oncoimmunology. 2025 Dec;14(1):2508050. doi: 10.1080/2162402X.2025.2508050. Epub 2025 May 27.
Antibody-epitope conjugates (AECs) proved to be a promising new therapeutic strategy to redirect virus-specific CD8 T cells toward cancer cells by delivering T-cell epitopes. To be able to redirect a larger fraction of the virus-specific T-cell population, it is beneficial to deliver a broader selection of T-cell epitopes. We investigated two different methods to generate AECs with two distinct virus-specific T-cell epitopes fused to one antibody. Epitopes were either placed in a tandem-like fashion at the C-terminus of the AEC (t-AEC) or bispecific-AECs (bs-AECs) were generated via controlled Fab-arm exchange to generate bs-AECs with two identical antigen binding domains, but two distinct epitopes on each Fab-arm. Our study revealed that maintaining a free epitope terminus was required for efficient delivery of the virus-specific T-cell epitopes. Consequently, viral-epitope delivery using t-AECs was suboptimal as the concatenated epitopes were less effectively delivered to the target cells. However, well-defined bs-AECs containing both CMV and EBV epitopes were successfully generated and both and efficacy was evaluated. Our results demonstrate that bispecific-AECs can efficiently deliver EBV and CMV epitopes simultaneously to multiple cancer cell lines from different origins, thereby redirecting and activating two distinct populations of virus-specific T cells. Furthermore, our findings indicate that when both virus-specific T-cell populations are present and tumor cells express the proteases required for efficient epitope delivery, bs-AECs exhibit similar efficacy in reducing tumor burden compared to AECs. To conclude, our study demonstrates the feasibility of redirecting two groups of virus-specific T cells using a single antibody and highlights the potential of bs-AECs both and .
抗体 - 表位偶联物（AECs）被证明是一种很有前景的新治疗策略，可通过递送T细胞表位将病毒特异性CD8 T细胞重定向至癌细胞。为了能够重定向更大比例的病毒特异性T细胞群体，递送更广泛的T细胞表位选择是有益的。我们研究了两种不同的方法来生成AECs，即将两种不同的病毒特异性T细胞表位与一种抗体融合。表位要么以串联样方式置于AEC的C末端（t - AEC），要么通过可控的Fab臂交换生成双特异性AECs（bs - AECs），以产生具有两个相同抗原结合域但每个Fab臂上有两个不同表位的bs - AECs。我们的研究表明，有效递送病毒特异性T细胞表位需要保持表位末端游离。因此，使用t - AECs进行病毒表位递送效果欠佳，因为串联的表位向靶细胞的递送效率较低。然而，成功生成了同时包含巨细胞病毒（CMV）和EB病毒（EBV）表位的明确bs - AECs，并对其疗效进行了评估。我们的结果表明，双特异性AECs可以同时有效地将EBV和CMV表位递送至来自不同来源的多种癌细胞系，从而重定向并激活两个不同的病毒特异性T细胞群体。此外，我们的研究结果表明，当两种病毒特异性T细胞群体均存在且肿瘤细胞表达有效表位递送所需的蛋白酶时，与AECs相比，bs - AECs在减轻肿瘤负担方面表现出相似的疗效。总之，我们的研究证明了使用单一抗体重定向两组病毒特异性T细胞的可行性，并突出了bs - AECs在[此处原文缺失相关内容]和[此处原文缺失相关内容]方面的潜力。
