Izadi Shiva, Abrantes Rafaela, Gumpelmair Simon, Kunnummel Vinny, Duarte Henrique O, Steinberger Peter, Reis Celso A, Castilho Alexandra
Department of Biotechnology and Food Science Institute of Plant Biotechnology and Cell Biology, BOKU University, Muthgasse 18, 1190, Vienna, Austria.
i3S Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.
Plant Cell Rep. 2025 Mar 22;44(4):80. doi: 10.1007/s00299-025-03475-0.
Plant-made PD1-Fc fusions engineered for optimized glycosylation and Fc-receptor engagement are highly efficient in blocking PD1/PDL1 interactions and can be cost-effective alternatives to antibody-based immune checkpoint inhibitors. Immune checkpoint inhibitors (ICIs) are antibodies to receptors that have pivotal roles during T-cell activation processes. The programmed cell death 1 (PD1) can be regarded as the primary immune checkpoint and antibodies targeting PD1 or its ligand PDL1 have revolutionized immunotherapy of cancer. However, the majority of patients fail to respond, and treatment resistance as well as immune-related adverse events are commonly associated with this therapy. Alternatives to antibody-based ICIs targeting the PD1 pathway may bear the potential to overcome some of these shortcomings. Here, we have used a plant expression platform based on the tobacco relative Nicotiana benthamiana to generate immunoglobulin fusion proteins harboring the wild type or an affinity-enhanced PD1 ectodomain. We have exploited the versatility of our system to generate variants that differed regarding their glycosylation profile as well as their capability to engage Fc-receptors. Unlike its wild-type counterpart, the affinity-enhanced versions showed strongly augmented capabilities to engage PDL1 in both protein- and cell-based assays. Moreover, in contrast with clinical antibodies, their binding is not affected by the glycosylation status of PDL1. Importantly, we could demonstrate that the plant-made PD1 fusion proteins are highly efficient in blocking inhibitory PD1 signaling in a T cell reporter assay. Taken together, our study highlights the utility of our plant-based protein expression platform to generate biologics with therapeutic potential. Targeting PDL1 with plant derived affinity-enhanced PD1 immunoglobulin fusion proteins may reduce overstimulation associated with antibody-based therapies while retaining favorable features of ICIs such as long serum half-life.
经过工程改造以实现优化糖基化和Fc受体结合的植物源PD1-Fc融合蛋白在阻断PD1/PDL1相互作用方面非常高效，并且可能成为基于抗体的免疫检查点抑制剂的经济有效替代方案。免疫检查点抑制剂（ICIs）是针对在T细胞激活过程中起关键作用的受体的抗体。程序性细胞死亡1（PD1）可被视为主要的免疫检查点，靶向PD1或其配体PDL1的抗体彻底改变了癌症免疫疗法。然而，大多数患者没有反应，治疗耐药性以及免疫相关不良事件通常与这种疗法相关。靶向PD1途径的基于抗体的ICIs的替代方案可能具有克服其中一些缺点的潜力。在这里，我们使用了基于烟草近缘种本氏烟草的植物表达平台来生成携带野生型或亲和力增强型PD1胞外域的免疫球蛋白融合蛋白。我们利用系统的多功能性来生成在糖基化谱以及与Fc受体结合能力方面有所不同的变体。与其野生型对应物不同，亲和力增强型变体在基于蛋白质和细胞的试验中显示出与PDL1结合的能力大幅增强。此外，与临床抗体不同，它们的结合不受PDL1糖基化状态的影响。重要的是，我们可以证明植物源PD1融合蛋白在T细胞报告基因试验中能够高效阻断抑制性PD1信号传导。综上所述，我们的研究突出了我们基于植物的蛋白质表达平台在生成具有治疗潜力的生物制剂方面的实用性。用植物源亲和力增强型PD1免疫球蛋白融合蛋白靶向PDL1可能会减少与基于抗体的疗法相关的过度刺激，同时保留ICIs的有利特征，如长血清半衰期。
