Engineered ACE2 receptor traps potently neutralize SARS-CoV-2.
Engineered ACE2 receptor traps potently neutralize SARS-CoV-2.
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DOI：
10.1073/pnas.2016093117
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发表时间：
2020-11-10
影响因子：
11.1
通讯作者：
Wells JA
中科院分区：
文献类型：
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作者：
Glasgow A;Glasgow J;Limonta D;Solomon P;Lui I;Zhang Y;Nix MA;Rettko NJ;Zha S;Yamin R;Kao K;Rosenberg OS;Ravetch JV;Wiita AP;Leung KK;Lim SA;Zhou XX;Hobman TC;Kortemme T;Wells JA
在持续的COVID-19大流行期间，蛋白质工程为构建治疗严重急性呼吸综合征冠状病毒2（SARS-CoV-2）感染的疗法提供了快速而强大的方法。我们使用计算机设计，亲和力成熟，融合二聚化结构域工程师的“受体陷阱”的基础上野生型血管紧张素转换酶II（ACE 2），病毒刺突介导的SARS冠状病毒2进入细胞的目标。优化的ACE 2受体陷阱可以有效地中和真正的SARS-CoV-2感染，就像从康复期患者中分离的高亲和力抗体一样，并且还可以结合已知引起呼吸道疾病的其他冠状病毒的病毒刺突蛋白。ACE 2受体陷阱具有大的结合界面，并阻断整个受体结合界面，限制了病毒逃逸突变的潜在影响。严重急性呼吸综合征冠状病毒1型（SARS-CoV-1）和严重急性呼吸综合征冠状病毒2型（SARS-CoV-2）感染的基本机制始于病毒刺突蛋白与人受体蛋白血管紧张素转换酶II（ACE 2）的结合。在这里，我们描述了一种逐步工程方法，以产生一组亲和力优化，酶失活的ACE 2变体，有效地阻止SARS-CoV-2感染的细胞。这些优化的受体陷阱紧密结合病毒刺突蛋白的受体结合结构域（RBD）并防止进入宿主细胞。我们首先使用两阶段灵活的蛋白质骨架设计过程计算设计ACE 2-RBD界面，该过程将RBD的亲和力提高了12倍。通过随机诱变和使用酵母表面展示的选择，使这些设计的受体变体亲和力成熟另外14倍。最高亲和力的变体包含7个氨基酸的变化，与RBD的结合比野生型ACE 2紧密170倍。通过添加天然ACE 2 collectrin结构域并与人免疫球蛋白可结晶片段（Fc）结构域融合以增加稳定性和亲合力，最佳ACE 2受体陷阱可中和SARS-CoV-2假型慢病毒和真实SARS-CoV-2病毒，半数最大抑制浓度（IC 50）在10- 100 ng/mL范围内。工程ACE 2受体陷阱提供了一种有希望的途径来对抗SARS-CoV-2和其他使用ACE 2的冠状病毒的感染，其关键优势是病毒抗性也可能削弱病毒进入。此外，这种陷阱可以预先设计用于具有已知进入受体的病毒，以获得更快的治疗反应，而不需要从康复期患者中分离的中和抗体。
During the ongoing COVID-19 pandemic, protein engineering offers a rapid and powerful approach for building therapeutics to treat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. We use computational design, affinity maturation, and fusion to dimerization domains to engineer “receptor traps” based on wild-type angiotensin-converting enzyme II (ACE2), the target for viral spike-mediated SARS-CoV-2 entry into cells. The optimized ACE2 receptor traps neutralize authentic SARS-CoV-2 infections as effectively as high-affinity antibodies isolated from convalescent patients and also bind viral spike proteins from other coronaviruses known to cause respiratory diseases. ACE2 receptor traps have large binding interfaces and block the entire receptor binding interface, limiting the potential impact of viral escape mutations. An essential mechanism for severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection begins with the viral spike protein binding to the human receptor protein angiotensin-converting enzyme II (ACE2). Here, we describe a stepwise engineering approach to generate a set of affinity optimized, enzymatically inactivated ACE2 variants that potently block SARS-CoV-2 infection of cells. These optimized receptor traps tightly bind the receptor binding domain (RBD) of the viral spike protein and prevent entry into host cells. We first computationally designed the ACE2–RBD interface using a two-stage flexible protein backbone design process that improved affinity for the RBD by up to 12-fold. These designed receptor variants were affinity matured an additional 14-fold by random mutagenesis and selection using yeast surface display. The highest-affinity variant contained seven amino acid changes and bound to the RBD 170-fold more tightly than wild-type ACE2. With the addition of the natural ACE2 collectrin domain and fusion to a human immunoglobulin crystallizable fragment (Fc) domain for increased stabilization and avidity, the most optimal ACE2 receptor traps neutralized SARS-CoV-2–pseudotyped lentivirus and authentic SARS-CoV-2 virus with half-maximal inhibitory concentrations (IC50s) in the 10- to 100-ng/mL range. Engineered ACE2 receptor traps offer a promising route to fighting infections by SARS-CoV-2 and other ACE2-using coronaviruses, with the key advantage that viral resistance would also likely impair viral entry. Moreover, such traps can be predesigned for viruses with known entry receptors for faster therapeutic response without the need for neutralizing antibodies isolated from convalescent patients.