由蛋白水解加工条件激活工程亲和力蛋白是广泛应用的有趣方法。我们使用内部开发的葡萄球菌展示方法生成了一种与EGFR靶向afibbody分子结合表面具有特异性的抗白痴蒙面域。通过链连接一个蛋白酶剪切位点，蒙面域可以特异性地废除癌细胞上的EGFR结合。通过蛋白酶剪切链接区域而释放蒙面域，可以恢复EGFR结合。饱和突变研究提供了关于EGFR靶向afibbody分子和蒙面域之间相互作用的详细信息。引入一种抗白痴蒙面afibbody结构域是封锁EGFR结合的可行方法，同时也可以通过蛋白水解加工得以有条件激活。结果需要进一步研究在体内外的治疗和诊断应用。版权所有©2022作者。由Elsevier BV出版。保留所有权利。

Conditional activation of engineered affinity proteins by proteolytic processing is an interesting approach for a wide range of applications. We have generated an anti-idiotypic masking domain with specificity for the binding surface of an EGFR-targeting affibody molecule using an in-house developed staphylococcal display method. The masking domain could specifically abrogate EGFR-binding on cancer cells when fused to the EGFR-targeting affibody molecule via a linker comprising a protease cleavage site. EGFR-binding was restored by proteolytic cleavage of the linker region resulting in release of the masking domain. A saturation mutagenesis study provided detailed information on the interaction between the EGFR-targeting affibody molecule and the masking domain. Introducing an anti-idiotypic masking affibody domain is a viable approach for blocking EGFR-binding and allows for conditional activation by proteolytic processing. The results warrant further studies evaluating the therapeutic and diagnostic applicability both in vitro and in vivo.Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.