Institute for Organic Chemistry and Biochemistry, Technical University of Darmstadt, Darmstadt, Germany.
Ferring Darmstadt Laboratory, Biologics Technology and Development, Darmstadt, Germany.
Front Immunol. 2022 Apr 11;13:888838. doi: 10.3389/fimmu.2022.888838. eCollection 2022.
Various formats of bispecific antibodies exist, among them Two-in-One antibodies in which each Fab arm can bind to two different antigens. Their IgG-like architecture accounts for low immunogenicity and also circumvents laborious engineering and purification steps to facilitate correct chain pairing. Here we report for the first time the identification of a Two-in-One antibody by yeast surface display (YSD) screening of chicken-derived immune libraries. The resulting antibody simultaneously targets the epidermal growth factor receptor (EGFR) and programmed death-ligand 1 (PD-L1) at the same Fv fragment with two non-overlapping paratopes. The dual action Fab is capable of inhibiting EGFR signaling by binding to dimerization domain II as well as blocking the PD-1/PD-L1 interaction. Furthermore, the Two-in-One antibody demonstrates specific cellular binding properties on EGFR/PD-L1 double positive tumor cells. The presented strategy relies solely on screening of combinational immune-libraries and obviates the need for any additional CDR engineering as described in previous reports. Therefore, this study paves the way for further development of therapeutic antibodies derived from avian immunization with novel and tailor-made binding properties.
存在各种形式的双特异性抗体，其中包括二合一抗体，每个 Fab 臂可以结合两个不同的抗原。其 IgG 样结构导致其免疫原性低，同时也避免了繁琐的工程和纯化步骤，从而有利于正确的链配对。在这里，我们首次通过酵母表面展示（YSD）筛选鸡源性免疫文库，鉴定了一种二合一抗体。该抗体的同一个 Fv 片段同时靶向表皮生长因子受体（EGFR）和程序性死亡配体 1（PD-L1），具有两个非重叠的互补位。双功能 Fab 能够通过结合二聚化结构域 II 抑制 EGFR 信号传导，同时阻断 PD-1/PD-L1 相互作用。此外，该二合一抗体在 EGFR/PD-L1 双阳性肿瘤细胞上表现出特异性的细胞结合特性。所提出的策略仅依赖于组合免疫文库的筛选，避免了像之前报道中所描述的那样，需要任何额外的 CDR 工程。因此，这项研究为进一步开发源自禽类免疫的具有新型和定制结合特性的治疗性抗体铺平了道路。
