Neoleukin Therapeutics Inc., Seattle, WA, USA.
School of Public Health, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong Special Administrative Region, China.
Science. 2020 Dec 4;370(6521):1208-1214. doi: 10.1126/science.abe0075. Epub 2020 Nov 5.
We developed a de novo protein design strategy to swiftly engineer decoys for neutralizing pathogens that exploit extracellular host proteins to infect the cell. Our pipeline allowed the design, validation, and optimization of de novo human angiotensin-converting enzyme 2 (hACE2) decoys to neutralize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The best monovalent decoy, CTC-445.2, bound with low nanomolar affinity and high specificity to the receptor-binding domain (RBD) of the spike protein. Cryo-electron microscopy (cryo-EM) showed that the design is accurate and can simultaneously bind to all three RBDs of a single spike protein. Because the decoy replicates the spike protein target interface in hACE2, it is intrinsically resilient to viral mutational escape. A bivalent decoy, CTC-445.2d, showed ~10-fold improvement in binding. CTC-445.2d potently neutralized SARS-CoV-2 infection of cells in vitro, and a single intranasal prophylactic dose of decoy protected Syrian hamsters from a subsequent lethal SARS-CoV-2 challenge.
我们开发了一种从头设计蛋白质的策略，以快速设计针对利用细胞外宿主蛋白感染细胞的病原体的诱饵。我们的流水线允许设计、验证和优化从头设计的人类血管紧张素转换酶 2（hACE2）诱饵来中和严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）。最好的单价诱饵 CTC-445.2 以低纳摩尔亲和力和高特异性结合到 Spike 蛋白的受体结合域（RBD）。冷冻电镜（cryo-EM）显示该设计准确无误，可以同时结合单个 Spike 蛋白的所有三个 RBD。由于诱饵在 hACE2 中复制 Spike 蛋白靶标界面，因此它天生不易受到病毒突变逃逸的影响。二价诱饵 CTC-445.2d 的结合能力提高了约 10 倍。CTC-445.2d 能够有效地中和 SARS-CoV-2 在体外对细胞的感染，并且单次鼻腔预防性给予诱饵可以保护叙利亚仓鼠免受随后的致命 SARS-CoV-2 挑战。
